WO2014095279A1

WO2014095279A1 - Method for determining a temperature of a cell in a battery, determination device and battery

Info

Publication number: WO2014095279A1
Application number: PCT/EP2013/074880
Authority: WO
Inventors: Jürgen Wolf; Dietmar Vogt
Original assignee: Continental Automotive Gmbh
Priority date: 2012-12-21
Filing date: 2013-11-27
Publication date: 2014-06-26
Also published as: DE102012224312A1

Abstract

The invention relates to a method for determining a temperature (ϑ) of at least one cell (10) in a battery (20). The method provides the following steps: applying an excitation signal (sa) to the cell (10); detecting a reaction signal (sr) generated in the cell (10) by the application of the excitation signal; and determining a deviation between the excitation signal (sa) and the reaction signal (sr). A temperature value that reflects the temperature (ϑ) is provided by using a predetermined dependency (100-120), typical of the cell, between deviations and temperature values to the deviation. The excitation signal (sa) has a plurality of discretely or continuously distributed different frequency components. The reaction signal (sr) reflects the signal response of the at least one cell (10) to the reaction signal (sr). A corresponding determination device (30) and a battery (20) that are suitable for performing the method are additionally provided.

Description

description

A method of determining a temperature of a cell of a battery, detecting device and battery

The invention relates to the field of temperature monitoring for electrical cells. It is well known that galvanic cells, especially rechargeable cells, can take temporary or permanent damage if they overheat. From DE 23 54 178 C2 it is known to use a temperature sensor to detect in particular when charging with high currents overheating of cells of a battery. However, the temperature sensors represent an additional cost factor.

It is known from US 2012/0155507 A1 that the internal temperature of a rechargeable lithium ion cell can be measured by applying a sine current to a cell and detecting the phase offset of the resulting sine voltage. The temperature results from a known relationship between an anode or cathode temperature, the frequency of the sinusoidal current and the phase set between the sinusoidal current signal and the sinusoidal voltage signal. However, both a sine current source and a device for detecting the phase offset require a high circuit complexity and high-precision compo ^¬ elements. It is therefore an object of the invention to provide a way by which the temperature of a cell of a battery can be detected in a simple manner.

This object is achieved by the method, by the determination device and by the battery according to the independent claims. Preferred embodiments emerge with the features of the subclaims. The invention provides to determine a temperature of a cell by exciting an excitation signal with different frequency components around the cell. The resulting reaction signal is compared with the excitation signal, and there is a deviation of the reaction signal from the

Excitation signal determined. The deviation and, in particular, the intensity of the deviation can be mapped directly to the temperature, since the dependence between deviation and temperature is previously known and can be determined, for example, from experiments. It has been recognized that there is sufficient accuracy in the temperature detection, if distributed frequency components are provided in the excitation signal, so that the excitation signal much easier than a monofrequent signal (= a sinusoidal signal) can generate. In particular, interference factors such as harmonic distortion, time resolution or lack of linearity in the output stage, which generates the excitation signal, play no part in generating the excitation signal. Furthermore, no phase locked loops are necessary for detecting the phase offset, as is the case with sinusoidal signals.

Instead, the invention enables a particularly simple generation and evaluation of the associated reaction signal or the deviation. Furthermore, no analog or quasi-analog signal processing is required. Rather, it can be done with very simple, discrete-value and / or time-discrete ones

Components are the temperature determined according to the method described here. Due to the low complexity that requires the method described here, integration into existing components of a battery is possible, with a realization with simple already existing

Circuits or processors is possible, which are in principle not suitable for the generation and evaluation of monofrequenter signals due to their low temporal resolution or lack of amplitude precision. It is possible to use signal forms which are very simple to produce, so that the circuit does not have to be adapted to the signal processing, but the method performed can be adapted to available hardware. Further advantages result from the combinability with a charge balancing device, wherein the excitation signal can be generated by a device which also serves for charge compensation. The reaction signal can be detected with acquisition and evaluation components that are also used for

Monitoring the charge balance or voltage detection. In addition, the same lines can be used as they are used for charge equalization or for detecting a voltage or a current, which is associated with the cell or. This can be realized by slightly modifying a charge compensation device and / or a voltage monitoring device, which can perform the method shown here. A method is therefore described for determining a temperature of at least one cell of a battery. The Tem ^¬ temperature of the cell is in this case the temperature of the cathode, the anode and / or the electrolyte. Depending on the frequency components, an approximate average temperature within the cell, the cathode temperature and / or the anode temperature can be detected.

It is intended to apply the excitation signal to the cell. In this case, the excitation signal is applied to the current collector of the cell, for example by connecting a voltage ^¬ source, for example in the form of an active power source, and / or by connecting a passive current source in the sense of a current sink, for example by (variable) connecting the current collector via a bleed resistor. In particular, the excitation signal can be generated by

Varying the current, voltage and / or resistance of the active or passive voltage or current source or current sink. Either the connection and / or the mentioned signal sources themselves generate the frequency components of the excitation signal used according to the invention. The excitation signal can thus be generated actively by connecting to a current or voltage source, or passively by connecting a (negative) current source or current sink, for example in "

Form of a resistance. To generate the frequency components, the current or voltage sources or current sinks are also separated again, either to terminate the application of the excitation signal or to generate the frequency components of the excitation signal.

The separation and connection is an example of the variation of the connection between current or voltage sources or current sinks on the one hand and the at least one cell on the other hand and can be provided as discrete-value, in particular binary change, or as a continuous or quasi-continuous change with at least partially continuous course , In addition, one of the cells may be a power source, sink, or voltage source for another of the cells. The connection can be changed for example with a switch element or by a variable resistor or an electronic output stage or by a pulse width modulated connection. In an exemplary embodiment, at least a proportion of 50%, 70% or 80% of the power spectrum of the relevant pulse width modulation is more than 300, 500 or 1000 heart. Further, the current source, sink or voltage source itself may be switchable or, more generally, variable, thereby generating the excitation signal, or a connection leading from the current source, current sink or voltage source may be variably provided.

Furthermore, the reaction signal is detected, which results from the application in the cell. The reaction signal can be determined as a voltage or current signal, or as a signal representing the complex, real or imaginary internal resistance of the cell in question. The Reakti ^¬ onssignal results from the frequency-dependent impedance of the battery and the excitation signal. The response signal occurs at the current conductors of the cell, and in the case of a current signal corresponds to the current component flowing towards or away from the cell due to the application of the excitation signal. Furthermore, a deviation of the reaction signal from the excitation signal is determined. This deviation is quantitative (for example in the form of a time, a time offset, a Integ ^¬ rationsfläche, a cross-correlation result, a pitch or a different size), or may be specified as the quantity, for example in a qualitative difference - as a change of the time course or the history form - that can be rendered as a value or a value tuple. The deviation relates in particular to the time profile of the respective signals. The deviation may be determined by normalizing at least one of the signals having a value which is a scalar or representing a physical value including a physical unit. Preferably, the deviation is determined by means of a

Reaction signal and possibly continue on the basis of a

Excitation signal.

This signal or these signals can be reproduced as a numeric value or as numerical values, for example as a binary word or binary words. In addition, the reac ^¬ tion signal can be amplified prior to submitting, or as part of identifying particular. The deviation can be detected by looking at the reaction signal alone (possibly also with respect to a given reference) and / or by comparing the reaction signal with the excitation signal, for example by forming a signal difference between the reaction signal and the excitation signal. The reaction signal and / or the excitation signal can be reproduced in the determination of the deviation as a value or value tuple (or as a consequence). The value or the value tuple reflects at least one signal property of the respective signal, in particular a property of the signal in the frequency domain and / or in the time domain. The deviation or the result of the comparison or the signal ^¬ difference can also be provided as a value or value tuple (or as a consequence).

Furthermore, a temperature value is provided which represents the temperature of the cell by establishing a relationship between sigma naldifferenzen and temperature values on the deviation is averted. The relationship between deviations and Tem ^¬ peraturwerten is predetermined and in particular for the cell typical. The dependency is characteristic in particular for cell chemistry or for the cell type. Cells having the same chemical composition of cathode and anode have the same cell type. Alternatively, it can be defined that all cells of the same cell type are the same

Having major reducing agent or major oxidizing agent. For example, all lithium-based cells may be associated with the same cell type. As cells, for example, Li-based cells, lead-acid cells, NiMH cells or other cells can be used. The battery comprising the cells is preferably designed as a traction battery of a motor vehicle (electric or hybrid vehicle, electric bicycle, electric scooter, etc.) or as a starter battery of a motor vehicle.

The excitation signal has several different frequency components. These can be distributed discretely or continuously. There is thus more than one frequency component which is at least 2 10%, 20% or 50% of the total power of the

Spectrum of the excitation signal corresponds. The reaction signal represents the signal response of the at least one cell to the response signal. The signal response also represents the impedance of the cell for the excitation signal, which impedance may depend on the frequency of said frequency components. The signal response may thus reflect the impedance or reactance of the cell. Alternatively, the signal response represents a unitless quantity representing a relationship between the response signal and the excitation signal. Finally, it can be provided that the excitation signal is a current, voltage or impedance signal. Likewise, the response signal is a current, voltage or impedance signal. In specific embodiments, the excitation signal is on Current signal, and the response signal is a voltage signal or an impedance signal. In further embodiments, the excitation signal is a voltage signal and the response signal is a current signal or an impedance signal. In both cases, the reaction signal can also reflect the time course of an impedance or a reactance of the cell. The changing of a resistor (switch) applied to the cell to excite it according to the method is referred to as an impedance signal and can also be understood as a current signal, since a variable current flow is generated as an excitation signal by changing the impedance. The reaction signal can be measured as an impedance, in particular as an impedance curve.

The resistance or its connection to the cell can be changed in binary or in two stages, in several stages, quasi-continuously or continuously. The switchable or variable resistor can in particular be reproduced by a transistor whose volume resistance corresponds to the (variable) resistance and whose control terminal is used to set the change or to switch.

According to one embodiment of the method, the Anre ^¬ acceleration signal at least on a jump. The response signal corresponds to the signal response to this at least one jump. The jump corresponds approximately to a change of a first

Amplitude value to a second, different amplitude value. The first amplitude value may be greater or less than the second amplitude value. The first or the second amplitude value may correspond to a value of zero. Furthermore, the first and / or the second amplitude value may be positive or negative. In particular, both amplitudes can be positive or negative. Particularly preferred is a jump from a first Amplitu ^¬ value greater than zero to an amplitude of zero or a jump from an amplitude of zero to a positive amplitude value.

An exemplary embodiment provides that the amendments ^¬ approach speed of the amplitude during the change, and in particular during the jump preferably greater than 50, 70 or 90 percent of the difference between the amplitude values based on a time period of not more than 100 ys, before ^¬ preferably not more than 50 ys particularly preferably not more than 1 is ys. Depending on the type of cell, the rate of change and thus the time period to which the change relates can vary widely. For example, the time span may not be more than 1 s, 100 ms, or 10 ms or may not be more than 100 ns, 10 ns, or 1 ns. In particular, the rate of change increases with ion mobility for different cell types. The ion mobility may be defined by the ion current to an electrode or away from an electrode relative to an applied potential difference of the electrodes or based on an electric field strength at one or both electrodes or between the electrodes.

Such a change or jump, in particular a change in the form of a jump function, automatically leads to the plurality of frequency components. Furthermore, a jump is particularly easy to generate, for example by switching. This switching is preferably electronic and can be provided in particular by a semiconductor component. The change may be monotonically increasing or linear, may mimic a jump function or a direct impact, may be aperiodic, or may mimic a negative-exponential function.

According to a further embodiment, the signal difference relates to a single edge of the excitation signal. This edge preferably corresponds to said jump. The response signal represents a relaxation response of the at least one cell, the relaxation response in particular representing the internal electrochemical and / or electrostatic response of the cell to the jump or flank and generally to the excitation signal.

Alternatively, the signal difference refers to an excitation signal provided as a binary signal. The excitation signal is a binary signal with several edges or with several Jumps, as mentioned above. The step of applying the excitation signal, the step of detecting the response signal and / or the step of determining the signal difference may comprise a filtering step.

This filtering step corresponds to a low-pass or band-pass filters of the respective signal, that is the excitation signal, the response signal and / or the Signaldiffe ^¬ rence. The filtered signal includes a plurality of discrete or continuously distributed kon ^¬ different frequency components, as described herein. If a binary signal with several jumps or edges is used for excitation, there is a greater signal energy and in particular several jumps are available for evaluation at once, so that the deviation can have a better signal to noise ratio than when using individual edges for evaluation. The binary signal preferably has a periodicity which encompasses several individual edges of the binary signal, in particular more than 2, 4, 16, 64, 256 or more. If the deviation is determined as a correlation of the excitation signal and the reaction signal, the higher periodicity results in the aforementioned higher signal-to-noise ratio.

A further embodiment provides that the excitation signal is provided as a binary signal and the signal difference refers to this binary signal, and not only to individual edges of the binary signal. The binary signal may be a noise signal, in particular a pseudo noise signal. In particular, the pseudo noise signal can be generated with a feedback shift register, which ensures, for example, the said periodicity. Further, it is provided that at least 50%, 70%, 80% or 90% of all time intervals between two aufei ^¬ nanderfolgenden flanks of the binary signal is not smaller than a first predetermined period of time. This time duration may be at least 1 ys, 10 ys, 100 ys, 0.5 ms, 1 ms, 2 ms, 5 ms or more in an exemplary embodiment. Furthermore, the said time intervals are preferably not greater than a predetermined additional period of time. The predetermined additional period of time may be 100 ys, 500 ys, 1 ms, 2 ms, 5 ms, 10 ms, 20 ms or 25 ms. The predetermined additional period of time is preferably greater than the first predetermined period of time. In a particular embodiment this is true for substantially 100% of all time intervals, or for at least 20%, 40%, 60%, 80%, 90% or 95% of all time intervals. This condition can be generated with a feedback shift register and a possibly downstream puncturing / padding device, wherein the puncturing / padding device clears edges which appear at an output of the shift register in less than 0.5 ms after the preceding edge. Furthermore, this device can insert an edge if more than 20 or 25 ms have elapsed instead of the preceding edge which outputs the shift register. The values 0.5 ms and 25 ms are only examples. Instead of 0.5 ms, values of 0.1, 0.2 or 1 ms can also be used. Instead of the value of 25 ms, values of 15, 20, 25, 30 or 35 ms can also be used. Puncturing is the deliberate deletion or omission of individual pulses or groups of impulses. Padding is the deliberate insertion of individual impulses or groups of impulses into a signal or into a pulse sequence. The terms puncturing and padding are used in accordance with the term content that these terms have in the field of computer science and discrete signal processing or communications engineering.

The noise signal may also be generated by retrieving a look-up table which represents the amplitudes or times of occurrence of the flanks, wherein the list for generating the binary ^¬ signal can be repeatedly retrieved. The use of a shift register is merely exemplary; instead, solutions may also be provided in which a corresponding program code and an associated processor on which it runs provide this function. Due to the conditions mentioned for the time intervals between successive edges of the binary signal is achieved that the resulting signal difference is particularly meaningful for the temperature.

In a further embodiment, the signal difference is determined by cross-correlation of the excitation signal and the associated reaction signal or vice versa. Furthermore, the Reaction signal are correlated with a reference signal, which at least one signal property of the excitation signal as ^¬ returns. The correlation result of the cross-correlation is used as the signal difference in the step of determining the temperature value. In this case, the dependency indicates a relationship between the correlation result values and the temperature value. The correlation result is particularly repre ^¬ advantage by a time offset of a maximum of Korrelati ^¬ onsergebnisses to a zero point of the time axis, which forms the basis of the cross-correlation. Alternatively, the amplitude of the maximum of the correlation result is used as a deviation, so that the value of the correlation maximum is offset by the dependence of a specific temperature. Furthermore, the area of the correlation result and thus the power can be used as a signal difference, preferably the area of the correlation result up to a predetermined, maximum time offset of the correlation. In an exemplary embodiment, the maximum time offset is 10, 15, 20, 25 or 30 ms, preferably 35, 50 or 70 ms. Other exemplary embodiments provide a maximum time offset of 1 ys, 10 ys, 50 ys, 100 ys or 1 ms. In addition, exemplary embodiments may provide a maximum time offset of 100 ms, 1s, 2s, or more. The maximum time shift can be determined by the ion mobility of the respective cell type and is preferably designed such that, within the maximum time offset, the relaxation in the cell and into ^¬ particular at the electrodes 50, 80 or 90% is finished. For cell types with high ion mobility under normal conditions (such as at a temperature of 20 ° C), the time lag is smaller than for cell types with lesser ion mobility compared to cell types. Here is relevant inter alia, that the first-mentioned ion mobility is greater than the second-mentioned Io ^¬ nenmobilität. Furthermore, it can be provided that the deviation is determined by detecting a time offset between the excitation signal (or a time that characterizes it) on the one hand and the associated reaction signal on the other hand. The time offset is at the step of determining the temperature value used as a deviation. The time offset can in particular be represented by a time constant, which is formed by the intersection of a tangent of the reaction signal with the time axis. The tangent is preferably applied at a time of the response signal immediately following an edge of the response signal. The time constant represents the time constant of the relaxation response. The time offset may also be reproduced by the time at which the response signal at least exceeds a predetermined threshold value or un ^¬ terschreitet as set forth below. The time offset can also be detected by means of a matched filter, which is designed in accordance with the excitation signal or a reference reaction signal. The time difference with respect to the excitation signal or the reference reaction signal, which can reflect a certain temperature, is used as a deviation to the temperature determination. The deviation from the reference reaction signal corresponds to the difference between the cell temperature to be detected and the particular temperature represented by the reference reaction signal.

Furthermore, it can be provided that the deviation is determined by comparing the reaction result with 1, 2 or more threshold values. The threshold values each correspond to an amplitude or control value. The at least one time ^¬ offset between the jump of the excitation signal and the

Crossing the at least one threshold value by the added ^¬ impaired response signal is used as the signal difference. The thresholds reflect how far the relaxation process of the cell has progressed. The associated time offset reflects how long the relaxation process of the cell takes to reach a certain degree of completeness (represented by the thresholds). In a particularly simple embodiment, only one

Threshold used, the use of two different ^¬ thresholds or more thresholds possibly allow a more precise result. If several thresholds used, then there are several time offsets. The time offsets (one time offset per threshold) are compared to a temperature value, so that the dependency assigns a threshold value to several time offsets. Alternatively, each time offset can be individually compared to a temperature, so that there are several dependencies. For each

Threshold results in a dependency. The temperature values thus determined by a plurality of threshold values can be combined, for example by averaging or median formation or by sorting or else by means of a best-fit adaptation method which assigns the most probable temperature value to the plurality of time offsets. Furthermore, when using a plurality of threshold values, the threshold values may be assigned to different occurrence locations of the respective temperature, since, for example, the anode temperature has a different dependence on the time offset than the cathode temperature. There may be several dependencies thereby, with each dependency being significant for a particular (other) point within the cell, for example, for the anode and for the cathode.

Furthermore, it can be provided that the deviation is determined by integration of the area of the reaction signal from the moment of the jump of the excitation signal. The area is used as a deviation in the step of providing the temperature value. The integration is a temporal integration. This can in particular be realized by adding up several amplitude values from the moment of the jump. The integration can be ended when the reaction signal falls below a predetermined threshold. The latter possibility can be used to suppress noise signals at low amplitudes.

The aforementioned possibilities show different possibilities of realization, which can be chosen depending on the field of application. Furthermore, it can be weighed between a particularly simple realization and high precision of the method. The above possibilities provide that for detecting the deviation of the response signal and optionally also the excitation signal in the time domain be ^¬ seek is or are. Thus, the time profile of the reaction signal is compared with the time profile of the excitation signal (or a reference derived therefrom). Characteristics which are used to compare the two signals, ie which are used to determine the deviation, are here times of the response signal, or slopes of the reaction signal at different times, amplitude values of the reaction signal which are determined, for example, with at least one threshold in which the response signal has certain characteristics, such as a certain slope or a certain amplitude, or similarities in the course, which are determined by cross-correlation of excitation signal and reaction signal. Instead of the excitation signal, it is also possible to use a reference which reproduces at least one signal property of the excitation signal. The Sig ^¬ naleigenschaft is particularly a property of Anre ^¬ supply signal in the time domain or in frequency domain.

Another possibility is the detection of the deviation on the basis of the spectrum of the reaction signal. Here, the Reakti ^¬ onssignal is considered in the frequency domain. In particular, the reaction signal is compared with the excitation signal in the frequency domain.

A further embodiment therefore provides that the deviation is determined by comparing a level of at least one frequency component of the reaction signal with a level of at least one frequency component of the excitation signal of the same frequency. The deviation results from the result of the comparison of the levels of the frequency components. In this case, a part of the spectrum of the two signals (excitation signal and reaction signal) is picked out and the respective levels are compared with each other. In this case, only a single frequency of the response signal and the excitation signal will either be ^¬ seeks or there will be a frequency range of the response signal with a corresponding frequency range of the excitation signal compared. In particular, powers of the excitation ^signal and of the reaction signal are compared which have these for a specific frequency or for a certain frequency range (or for a plurality of frequency ranges). It is also possible to compare individual frequency components for a plurality of individual frequencies of the excitation signal and of the reaction signal. In particular, level means the power of the signal for the frequency or for the frequency range, by means of which the two signals are compared with one another. The mentioned embodiment compares a frequency component (or an amount of frequency components) of the response signal with a frequency component or an amount of frequency components of the response signal. Instead of comparing the frequency ^¬ components of the excitation signal can also be compared with reference values, reflecting the characteristics of the spectrum of the excitation signal.

Another possibility is to relate two frequency components of the reaction signal to one another in order to determine the deviation therefrom. (Since the reaction signal is UNMIT ^¬ nent consequence of the excitation signal and the excitation signal so that the deviation of the two signals is considered, even when only the spectrum of the response signal is considered is considered in this comparison indirectly.) The deviation of the by detecting Level or power difference determined by frequency components of the reaction signal. This be ^¬ particular meets two or more different fre ^¬ frequencies or frequency ranges of the reaction signal. The Fre ^¬ quenzkomponenten whose level differences are detected, have different frequencies. It is the Pegelun ^¬ terschied for certain frequency components of the reaction ^¬ signal with a corresponding level difference of the Fre ^¬ quenzkomponenten of these frequencies in the excitation signal is compared (or with values, the characteristics of these frequency components of the excitation signal or corresponding Re ^¬ preferences reflect). Since the levels and the level differences of the frequency components in the excitation signal are known, this can Comparisons may also be made by looking at the level difference of the response signal alone.

Furthermore, the spectral course of the reaction signal can also be evaluated in other ways, for example by ^comparison with spectrum profiles which are assigned to specific temperatures. With the greatest similarity of the spectrum of the reaction signal with one of the spectra, which are associated with temperatures, the spectrum with the greatest similarity to the spectrum of the reaction signal is determined and the associated, associated temperature is provided as a temperature value. As a measure of the similarity, at least one correlation result can be used, a difference or a combination of several differences, or even results of algorithms for the best possible adaptation or a method of least squares can be used.

According to a further embodiment, the excitation signal is applied via at least one line. At least one equalizing current flows through the line for charge equalization between the cells. The cable thus has a dual function, which significantly reduces the wiring, for example, compared to batteries in which each cell or some cells have a temperature sensor whose measurement signals are to be transmitted separately. The equalizing current can flow away from or be supplied to a cell, for example, starting from a central current sink or current source. Alternatively or in combination with this, the compensation current can flow between different cells via the line via which the excitation signal is also applied. Another possibility is to transmit the reaction signal via a line through which the compensation current flows. In particular, the line via which the reaction signal is transmitted can also be used to apply the excitation signal. This line corresponds preference ^¬, the line through which also flows from at least one ^¬ DC. A further embodiment provides that the excitation signal is generated by means of an output stage device, which also generates the compensation current for charge equalization between the cells. The output stage device generates a changing current or voltage signal, the change corresponding to the here described ^¬ stimulation signal. The output stage ^device may comprise electronic switches or (electronically) variable resistors, in particular transistors, in order to generate the compensation current as well as the excitation signal. Thus, such a power amplifier device has a dual function, as well as the previously explained line. The power amplifier means may be driven by a signal source which generates a signal which is converted to the excitation signal in the end ^¬ stage means. Furthermore, the signal source can generate a control signal that is converted by the output stage device into the compensation current. The output stage device can be integrated in the signal generator. The signal generator may in particular be provided by a microprocessor on which runs a corresponding program which realizes the functions described here, in particular the generation of the compensation current and the generation of the excitation signal.

As an excitation signal, a change in a load operated by the battery can be further considered. In ^¬ a switching play as (or changing the requested stream) of a load can make a jump, especially a

Generate current jump. As a load component of the electrical system or in general an electrical load of the vehicle can be ^¬ be distinguished here (motor vehicle in particular a as disclosed herein), which is supplied from cells of the battery. The resulting voltage step then corresponds to the Reakti ^¬ onssignal. In this way ^¬ nalgenerator possible to dispense with an additional Sig, as the current or voltage jumps are monitored by loads and are used as excitation signal to compare these with the resulting reaction signal. In other words, a variable load can be used as a current generator to generate the stimulus. be considered transmission signal. The excitation signal can be determined by means of a current sensor for detecting the cell or battery current. The response signal may be detected as a change (s) in the potential of one or more cells (each). The excitation signal may also be provided as a voltage change resulting from a change in a load being operated by the battery or cells. The response signal corresponds to the resulting change in the current flowing through the at least one cell.

It can thus be provided that the excitation signal is conditioned by changes in the load conditions in the electrical system which is connected to the cells, the changes occurring through controls or regulations outside the method proposed here, as described above. The excitation signal is therefore (passively) monitored and used for the temperature detection described here.

However, it can also be provided that changes in the load conditions in the electrical system are specifically caused by the method described here. The application of the excitation signal can therefore be provided by specifically directing at least one load or a consumer in the electrical system directly or indirectly to a change. In this case, a control signal is output, which reproduces the excitation signal or at least a time at which the excitation signal occurs or has at least one jump or pulse. The control signal may be output from the signal generator described herein. The control signal is implemented by a controller which controls at least one load or load supplied by the cells whose temperature is to be detected. This control or regulation can be implemented, for example, by a central control unit. As an example, an electric heater can be switched on and / or off, this switching generating the excitation signal which acts on the cells. If a setpoint is provided, with which the load or the consumer is to be controlled, wherein the setpoint represents, for example, the power or the current or another operating parameter, it can be provided that this setpoint is modified according to an excitation signal as described here , and the load or the consumer is driven with the modified setpoint. Preferably, the modified setpoint does not deviate more than 50%, 20%, 10 or preferably

2% or 1% of the specified value. This deviation relates in particular to nominal values which are averaged over a time window. Thus, for example, a short pulse or a group of pulses may be provided, with which a predetermined setpoint is modulated, wherein the load or the load is operated with the modulated setpoint. In the case of electrical heating, pulse modulation would only insignificantly change the operation of the heater, as long as the pulse modulation drives the heater at a power that substantially (i.e., with a deviation as mentioned above) corresponds to the predetermined power.

Also, between successive steps of application of the excitation signal, a minimum period of time may be provided, which is in particular a multiple of the duration of the application, for example a multiple of at least 10, 20, 50, 100 or 1000. As a result, even with deviations of not more than 50 % or 20% during the application of the excitation signal, the operation of the load are not changed we ^¬ sentlich. Also, a change of the predetermined target value of 50% or more would not appreciably change the operation of the load if this change lasts only for a period of time which is a fraction of the time period in which the change is repeated and the excitation signal is reapplied.

As a load or consumer whose predetermined setpoint is changed to apply the excitation signal, loads and consumers whose operation by the change in accordance with the

Excitation signal is not significantly affected. Loads and consumers are numerous electrical consumers, such as an electric heater, electromechanical Actuators, electric lighting or other components. Preferably, components are used as the load, which can not directly cause damage in case of malfunction. Further, components are preferably used as a load whose operation is not permanently or temporarily disturbed by a pulse in the control. In the case of vehicles are suitable as a load, an electric heater, actuators for operating comfort units such as electrically adjustable seats and ins ^¬ particular sluggish actuators, which in a control in the range of 100, 50, 10, 5 or 1 ms no significant mechanical

Change effect, the interior lighting, an electric traction drive, or other loads, in particular with a sluggish reaction behavior, the operation of which remains essentially unchanged for changes in the millisecond range. The inertia can result in actuators by masses, which are moved by these result in electrical Temperierungselementen (such as an electric heater) by heat capacities, which are coupled with these. The loads preferably have an inertia in the response which has a larger time constant than the duration of the application of the excitation signal or as the duration of pulses in the excitation signal.

The determining device may have an output for a signal that reflects the change of the setpoint (and thus characteristics of the excitation signal) or at least the time of the change. The output is designed to be connected to a module that implements the control or regulation of the load. The output may be configured to be connected to a data bus, such as a CAN bus. The above-described output can be integrated in at least one further output of the determination device. The outputs may be provided as a common physical element, such as a socket or other electromechanical contact unit.

It is possible to apply a common excitation signal to several or to all cells, while several reaction signals are detected individually at one or more cells. The cell specific response signals is in each case the common excitation signal (or corresponding references) ge ^¬ genübergestellt. It can thus be provided a signal generator which generates a common excitation signal for all or for a subset of the cells.

According to a further aspect, a determination device for determining a temperature of at least one cell of a battery is proposed. The temperature, as well as the cell and the battery correspond to the respective sizes or components of the method described here. The determination device comprises a signal generator, in particular the signal generator described here. The signal generator is set up to generate an excitation signal, in particular of the excitation signal described here with reference to the method. The excitation signal, for the generation of which the signal generator is set up, has several discrete or continuously distributed different frequency components. The Fre ^¬ quenzkomponenten correspond in particular to the frequency components described by the method.

A response signal detecting means of said determination device is adapted for detecting a reaction ^¬ signal generated by the cell. This reaction signal, for the detection of which the reaction signal detection device is set up, corresponds in particular to the reaction signal described here with reference to the method.

A deviation determination device of the determination device is set up to determine a deviation between the excitation signal and the reaction signal. The deviation, based on the actual deviation determining means is adapted in particular corresponds to the deviation from ^¬, as used with reference to the method described here.

The determination device comprises an imaging device, which is connected downstream of the deviation determination device. The imaging device provides the image as described herein with reference to the method. The imaging ^device is equipped with at least one predetermined dependency, typical for the cells, between signal differences and temperature values.

Finally, the determining device comprises an output interface, which is connected downstream of the imaging device. The output interface is set up to output a temperature value, in particular in the form of an electrical signal, for example in the form of a digital signal.

The signal generator may be configured to output a single jump signal, for example in the form of a

Toggle switch, or may be a binary, ternary, amplitude ^¬ discrete or amplitude continuous noise source, in particular a pseudo noise source, such as a feedback shift register or a corresponding

Equivalent in the form of a computer program which runs on a microprocessor.

The deviation detection means may comprise a correlator which is particularly adapted for Kreuzkorre ^¬ lation of the excitation signal to the associated reaction signal. Furthermore, the deviation determination device can have a time detection unit for detecting a time offset, as described here in the context of the method. In addition, the signal difference determination device can have a comparator or a plurality of comparators which have a threshold value input or which have a plurality of threshold value inputs. The thresholds of the comparator correspond to the thresholds described herein, and may be stored within the comparator or in a memory connected to the comparator. Furthermore, the deviation determination device may comprise an integrator, wherein in a simple case the comparator may be provided as a time-discrete adder element which adds new values to a sum in a memory added. The sum corresponds to the integral and in particular the area of the reaction signal when the response signal is supplied to the integrator. In addition, the deviation detecting device can operate in the frequency domain and have for example a Fourier transform ^¬ formation unit. In particular, the deviation determination device can compare individual frequency components of the reaction signal and / or of the excitation signal with one another, wherein the frequency components relate to at least one discrete frequency or to at least one frequency range. Furthermore, the deviation determination device may comprise a subtraction unit which is set up to detect the level difference described here.

The deviation determination device and the signal generator can be provided, in particular, as a microprocessor on which a program for realizing the functions runs. For the delivery of signals has a digital / analog converter unit. For recording signals, for example for recording the

Reaction signal or the excitation signal, the microprocessor may comprise an analog / digital converter.

Finally, the deviation detection device and / or the reaction signal detection device or also the signal generator may have a low-pass or a bandpass. In this case, the low pass or the bandpass is a part of the detection device or the signal generator and outputs the reaction signal, the excitation signal and / or the deviation.

In one embodiment of the method Determined ^¬ averaging device comprises a charge compensation device. The charge balancing device has an output stage device that is set up to generate a compensation current for the at least one cell. The equalizing current or the final stage device corresponds to the equalizing current or. the final stage, as described here by the method. The Sig ^¬ nalgenerator is driving with the output stage device connected. In a specific embodiment, the signal generator also serves to generate the compensation signal in which the signal generator is set up to deliver a control signal in order to drive the output stage device of the compensation current. The power amplifier device comprises an electronic switch, a transistor or the like, and may in particular be controlled to change the output current and turn into ^¬ particular between two levels. The power amplifier or the signal generator can also in one

DC / DC converter may be provided, which has an output which is connected directly or indirectly to the cells of the battery and which is in particular adapted to deliver current and / or the excitation signal to the cells. The output stage device may be an output stage of the DC / DC converter, which is connected to the output of the DC / DC converter.

An embodiment of the determining device provides that it further comprises at least one line or measuring interface. About this line or measuring interface is the at least one cell with the signal generator or with the

Power amplifier connected. Further, the at least one cell through said at least one line is connected to a charge ^¬ compensation device. The charge balancer is configured to generate a balancing current leading to or away from the at least one cell. The charge balancing device corresponds in particular to the charge balancing device described here.

The reaction signal detecting means can be realized in particular by means of a measuring unit of the Ladungsaus ^¬ same device, via which the charge compensation device detects a current, a voltage or potential of the cell. The reaction signal detection device and the measuring device of the charge balancing device can thus be formed as the same component, wherein the two functions described here (charge compensation and reaction signal detection) can be realized by different use of the signal. In a simple, exemplary case, a charge balancing device is provided with a measuring device, wherein the signals detected by the measuring device are not only used to control or regulate the charge balance, but also forwarded and further processed as described herein reaction signal as a response signal. This can be achieved by a mere tapping or by the fact that corresponding measured values are stored in the memory, which is not only retrieved from a charge equalization control, but is also retrieved by the determination device for determining the temperature described here.

In another aspect, a multi-cell battery is described which further includes a detection device as described herein.

Therefore, a multi-cell battery is described which includes a signal generator. The signal generator is arranged to generate an excitation signal comprising a plurality of discrete or continuously distributed different Fre ^¬ quenzkomponenten has. The signal generator may in particular correspond to the signal generator described here on the basis of the determination device. The signal generator is connected via lines to the cells. These lines lead in particular to the current conductors of the cells.

Current conductors of the cells are conductors that are electrically connected to the electrodes of the cells, preferably directly. The battery further comprises a reaction Sinai detection ^¬ device, in particular as described herein with reference to the Determined ^¬ averaging device. The response signal detecting means is arranged to detect a response signal generated by the cell. The reaction signal detection device is connected to the lines for detecting the reaction signal. The battery further comprises a deviation-determining ^¬ device, in particular as described here on the basis of Ermitt ^¬ treatment device. The deviation determination ^device is set up for determining a deviation of the reaction signal from the excitation signal and in particular a deviation between the excitation signal and the reaction signal, for all cells, for at least one subgroup of cells or for individual cells. In this case, the reaction signal can originate from several cells at the same time, so that the reaction signal reproduces the common relaxation response of the several cells.

The battery further comprises an imaging device, which in particular corresponds to the imaging device, as described here on the basis of the determination device. The imaging device is connected downstream of the dependence detection device. The imaging device is equipped with a dependency between deviations and temperature values, the dependencies being predetermined and being in particular typical for the type of cell. The type of cell is determined by the composition of the cathode and the anode and in particular by the main component, for example lithium. The battery further comprises an output interface, in particular ^¬ an output interface, as described here on the basis of the determination device. The output interface is connected downstream of the imaging device. The output interface is arranged to output a temperature value, in particular the temperature value that is output by the imaging device.

Alternatively (or in combination) with the output interface, the battery has an evaluation device. This is the imaging device downstream. The evaluation device comprises a comparator as well as a temperature limit value or at least one input at which a tempera ^¬ turgrenzwert can be received, in particular a memory, which can be present in the battery. The evaluation device is set up to output an error signal. The Auswer ^¬ processing device is preferably adapted to release the off ^¬ error signal to a current limiting device of the battery, such as a microcontroller and / or to a contactor within the power bus of the battery or to trigger devices which drives the contactor. The evaluation device is set up to output an error signal and preferably to output it only when a temperature value output by the imaging device (or by the output interface) exceeds the temperature limit value.

An embodiment of the battery provides that it further comprises a charge balancing device. The charge balancing device corresponds in particular to the charge balancing device described here on the basis of the determination device.

The charge balancing device is connected to the cells, preferably via the lines described here. The leads lead to taps between the cells with each other or between the cells and a power bus of the battery. The charge balancing device has an output stage device, in particular the output stage device described here on the basis of the determination device. The output stage device is arranged to generate a compensation current for charge equalization between the cells. The output stage device is further configured to generate the excitation signal which is applied to the cells. In this case, the output stage device is used for two functions, namely for charge compensation and for generating the excitation signal.

The lines are also used for two functions, namely the transmission of the compensation current for charge equalization and for the application of the excitation signal.

Furthermore, it can be provided that the reaction ^signal detection device is connected to the cells via these lines, that the function of transmitting the reaction signal is also realized by these lines.

The charge balancing device may further comprise a measuring device, which is preferably connected to the cells via said lines. In this case, the measuring device can also be used as a reaction signal detecting device, wherein the measuring device and the Reakti ^¬ onssignal detection device are provided as the same measuring device or detection device.

The method described here can be realized by a computer ^¬ program which is executed on a processor, wherein the processor has in particular the interfaces described herein. The processing of the reaction signal and / or the excitation signal described here can also be realized in front of the microprocessor in combination with the computer program. However, sub-steps or sub-functions may be realized by a non-hard-wired circuit, which may be digital or analog. In particular ^¬ sondere filtering may be provided by means of a firmly anchored circuit, the expansion joints and / or

Has inductors. Brief description of the drawings

Figure 1 shows an embodiment of a battery and a detection device as described herein;

Figures 2a-2d show embodiments of a deviation detecting device as described herein;

FIGS. 3a, 3b show further embodiments of the present invention

described deviation detecting means;

4a 4g show embodiments of the signal generator described herein, as well as exporting ^¬ approximately forms of reaction signals as be used according to the method described here;

Figure 5 shows embodiments of dependencies as described herein and

FIG. 6 shows reaction responses or reaction signals for a more detailed explanation of embodiments of the objects described here.

Detailed description of the drawings

1 shows the cells 10 of a battery 20 and a He ^¬ averaging means 30. In the illustrated embodiment, the detection device 30 is integrated in the battery 20, but these two components EMBODIMENTS also in other training may be provided separately from each other. In the latter case, an interface between the detection device and the cells 10 for connecting the battery and the detection device results. The determination device 30 includes a signal generator 40. The signal generator 40 is directed ^¬ for generating an excitation signal, as is described herein. The determination device 30 further comprises a reaction signal detection device 50. The reaction detection device 50 is followed by a deviation determination device 60. Furthermore, the determination device 30 comprises an imaging device 70, which is connected downstream of the deviation determination device 60. The determination device 30 finally comprises an output interface 80, which is connected downstream of the imaging device 70.

Further optional components of the determination device (and thus of the battery) shown in FIG. 1 are a charge balancing device 90, which is equipped with an output stage device 92, and an evaluation device 96, which is followed by an optional current limiting device 98. The cells 10 are connected in series. Each cell has two current conductors which are connected in series in a known manner for voltage addition. It is also possible for several cells connected in parallel to be connected in series with one another. For the serial connection of the cells 10 are their

Current conductor connected to the addition of cell voltages. The individual connections between the cells and also to a positive and negative current bus 12a, b for deriving the total current of the cells 10 each have a tap. To several of these taps or to all taps lines 14 are connected, which serve for cell monitoring. No additional taps are provided between the cells and the respective power bus, instead the power bus itself can be used as a tap for potential detection.

Via the lines 14, the cells 10 are connected to the detection device 30. For this purpose, an electrical interface can be provided, for example a plug contact interface via which the lines 14 connect the cells 10 to the determination device 30. For better representability, the lines 14 bundled as (signal) bus reproduced in Figure 1. The signal generator 40 is connected to at least one of these lines. Here, the signal generator 40 may be directly connected to all lines 40 or may be connected to the lines via a multiplexer or select switch to select one or more lines for connection to the signal generator 40.

The signal generator 40 is configured to generate an excitation signal, the transmission direction being represented by an arrow leading away from the signal generator 40. In this case, the signal generator 40 can itself generate the excitation signal that is applied to the cells 10, or can generate a signal that generates via excitation stages or drivers or output stages the excitation signal, which is then sent to the Cells 10 is created. Since the waveform and the purpose are the same, no further distinction is made between an excitation signal directly generated by the signal generator 40 and applied to the cells 10 and a signal generated by the signal generator 40 and amplified to the cells 10 is created. In a simple embodiment, the signal generator 40 is an electronic toggle switch that generates the excitation signal (s) for one or more cells. The signal generator 40 shown in FIG

Power source with variable current output can be considered. Alternatively, the signal generator 40 may be a voltage source that is variable in the output voltage.

The signal generator transmits via the power 14 (and optionally via a multiplexer and / or at least one output stage), the excitation signal to the cells 40. With multiple cells, a common excitation signal can be used, wherein at a different contact, as it is about Figure 1 also several different excitation signals can be generated by the signal generator 40, which are each applied to the cells individually.

With the lines 14, the reaction ^signal detection ^¬ device 50 is also connected directly or indirectly. The Sig- nalrichtung the response signal is provides with an arrow Darge ^¬ that leads to the response detection means 50 (in particular starting from the lines 14). The Reakti ^¬ onssignal may be a voltage signal or a current signal. In the case of a voltage signal, the response signal corresponds to the level (amplified, attenuated and / or filtered) applied to the

Lines 14 is applied or applied to the individual current conductors of the cells 10. In the case of a current signal, the signal detected by the reaction detector 50 corresponds to a current representing the current flowing between the cells 10 and the signal generator 40 (or its output stages). For picking up the reaction signal on the lines 14, a shunt resistor, a Hall sensor, an inductive tap on the lines 14 or another current sensor be used. The signal resulting from these current detection components is amplified, attenuated and / or filtered forwarded to the reaction signal detection means 50. In the reaction signal detecting means 50, the response signal can be processed, for example by Ver strengthen ^¬, vapors, filtering or by analog / digital conversion or by other signal processing processes. The

Reaction signal detecting means 50 outputs a signal corresponding to the response signal. Since the signal output from the response signal detection means 50 corresponds to the signal originally output from the cells 10, no distinction is made hereinafter between these signals. For example, in the case of a response signal, which is reproduced as a voltage, the reaction signal detection device 50 can also be a simple forwarding, if necessary with or without attenuation or else amplification. There would be a substantial identity between the signal output from the cells 10 via the lines 14 and the signal supplied to the signal difference detection means 60 as a response signal.

The determination device shown in FIG. 1 further comprises a signal difference determination device. This is designed to determine the deviation of the reaction signal from the excitation signal (or a corresponding predetermined reference) and in particular to determine a signal difference between the excitation signal and the reaction signal, which can be regarded as a deviation. The response signal is supplied from the response signal detecting means 50 to the deviation detecting means 60. Optionally, the excitation signal is also supplied to the signal difference detection means 60, preferably from the signal generator 40. Since waveform and / or timing (eg, exit time of at least one edge) or the spectrum of the excitation signal can be known, or a predefined reference containing at least one signal ^¬ feature of the excitation signal reproduces, may be given, it is possible that only the reaction signal to the signal difference determination means 60 is applied. In the latter case, the information about the course, the timing or the spectrum of the reaction signal or also the reference is already present in the deviation determination device 60 (without explicit detection of the current excitation signal). For this reason, the connection between the signal generator 40 and the deviation detection device 60 is optional and shown in dashed lines in FIG. The signal determination device is shown by way of example in FIGS. 2a-2d and 3a-3b.

The deviation determination device 60 is followed by the imaging device 70. The imaging device 70 receives the deviation from the deviation detection device, preferably in the form of a value or in the form of several values or else in the form of a signal that can be digital or analog. At least one dependency is provided in the imaging device 70, between deviations and temperatures, in particular between deviations or signal differences and temperature values.

The mapping may be provided as a parameter set, the parameters defining the dependency, for example in the form of an approximation function. Furthermore, the mapping can be provided by a look-up table, in which signal differences are compared with temperature ^values . Imager 70 may have multiple dependencies or a multi-dimensional dependency that not only compares signal differences and temperature values, but also represents the relationship between the temperature values and signal differences depending on the cell type or type of battery. Furthermore, several dependencies can be provided between the signal difference and the temperature, the dependencies being predetermined for different states of charge or aging states of the battery or of the cell (or also for different cell types or cell designs). The dependencies for multiple states of charge, aging states or cell types, or cell designs may be multidimensional It can be summarized that there is no distinction between multiple dependencies and a multi-dimensional dependency. Cell designs may be defined by a nominal capacitance, a rated peak output current, rated peak charging current, a rated continuous output current, a rated continuous charging current, a nominal internal resistance, a

Nominal temperature range, by a nominal temperature limit, by an application range and / or by a

Rated output voltage.

The determination device 30 shown in FIG. 1 also has an output interface 80. This may be as a separate electromechanical interface (such as a plug connection element ^¬) or logical interface provided, or as an internal interface of an overall system arrangement in which the detecting device is integrated 30th The

Interface may be provided as a space Ar ^¬ beitsspeichers in particular, in which a value is written. The output interface 80 is connected downstream of the imaging device 70 and is configured to output the temperature value of one or more cells. The information output by the output interface 80 is shown as a left arrow originating at the output interface. The data can thus be supplied to external devices. For this purpose, a data bus may be provided, such as a CAN bus, which transmits the information.

Alternatively or in combination with the output interface 80, the imaging device 70 can be set up to output a temperature value to an evaluation device 96. The evaluation device 96 comprises a comparator 97, which receives a temperature limit value 98, and a temperature value from the imaging device 70. The comparator compares the temperature value with the temperature limit value 98 and outputs an overtemperature signal when it is exceeded. This can be supplied to a display, can be supplied to a general control unit, or can be supplied to a current-limiting device 99. The current limiting device 99 is Preferably, provided in the battery 20, approximately within the power bus ^λ 12a of the cells 10 and the battery 20. The connection between the evaluation device 96 and current limiting device 99 is shown with a dashed line.

In a preferred embodiment, which can also be explained with reference to FIG. 1, the determination device 30 comprises a charge balancing device 90. This is connected via the lines 14 to the individual cells 10, in particular to the connections between the current conductors of the cells 10. The charge balancing device 90 comprises a power amplifier device 92. This is driven by a charge ^¬ balancing control unit 93 of the load balancer 90. the load balancing control unit 93 is arranged to switch the power amplifier means 92 and in particular is further adapted to current and / or to detect voltage values of the cells 10, in particular evaluated and in particular Also according to the evaluation to control a charge balance via the output stage device 92.

The signal generator 40 is also drivingly connected to the final stage device 92 for driving it to generate an excitation signal as described herein. Alternatively (not shown for clarity), the signal generator 40 and the charge balance control unit 93 may be provided by a common unit that performs both the charge equalization and the generation of the excitation signal. In particular, this unit can be a microprocessor, which can also have further functions, for example cell monitoring with regard to current, voltage, aging and / or charge state. If the output stage device 92 also assumes the generation or conversion of the excitation signal, no lines 14 between the cells and the signal generator are necessary, since the output stage device 92 implements the excitation signal. The signal generator 40 and / or the output stage device 92 or the charge balance control unit 93 can thus directly or indirectly beat a plurality of cells 10 via the lines 14 with all together or with individual excitation signals. In the case of several excitation signals, these can be applied to the cells 10 together via the lines, or a multiplexer can be provided which applies an excitation signal alternately to different cells 10 to the lines 14. In this sense, the connection of the lines 14 shown as a signal bus should also be understood, these individual lines may be via which individual excitation signals are excited (or reaction signals are detected) or it may be a multiplexer provided via a line Receives excitation signal and the cells 10 on. In the same way, a demultiplexer can be provided, which detects the reaction ^signals successively or simultaneously and this time buffered or unbuffered to the reaction ^¬ signal detection device 50 individually or subgroups passes.

In a further specific embodiment, the reaction signal detection device 50 is also integrated in the charge balancing device 90. The reaction ^signal detection device 50 may be provided in a uniform manner with a cell state detection device which monitors the signals transmitted via the lines 14 with regard to the charge state and / or health of the cells 10. These signals are transmitted by the cells 10 via the lines. FIG. 1 also shows the battery 20, in which the cells 10 and the components described above with reference to FIG. 1 are integrated, preferably in a common housing. In particular, the charge balance device 90 and the signal generator may be provided in the same housing. The charge balancing device 90 can furthermore be provided together with the reaction signal detection device 50 and / or with the deviation determination device 60 and possibly also with the imaging device 70 in a common housing be in which the cells are located. Such a housing has on the one hand a current interface for the power buses 12a, b, and optionally an interface 80. Instead of the output interface 80 may also Auswer ^¬ processing device may be provided 96, which is provided preferably also integrated in a common housing with the batteries 10 is. Likewise, the current limiting device 99 may be provided in a common housing with the cells 10. An interface of the evaluation device 96 can be provided, which can deliver the signal of the evaluation device 96 to external devices.

A further embodiment provides that no separate signal generator is provided for temperature detection, but the current emitted by the cells is detected as an excitation signal. A change of this current corresponds to the excitation signal. The change can be generated by a change in the load supplied by the cells. Such an embodiment can be illustrated with reference to FIG. 1, wherein the signal generator 40 and the connections leading away from it are omitted. Instead, an excitation signal detection device may be provided which monitors these changes in the indicated current of the cells and detects the current changes in the load as an excitation signal. Such ^¬ An excitation signal detecting apparatus would be connected to the deviation detecting means 60, such as via the dashed lines shown overall compound, which leads to the of the deviation ^¬ deviation detecting means 60th At the location of the signal generator 40, the excitation signal detection device would appear in a corresponding representation. For the sake of clarity, no excitation signal detecting device is shown explicitly in FIG. 1, wherein the rectangle with reference numeral 40 may represent an excitation signal detecting device for explaining the embodiment of this paragraph. A load change can occur as a load step, with the associated change due to the shape of the jump automatically leads to an excitation signal ^having different frequency ^¬ components, as described here. In Figures 2a - d show various exemplary deviate ^¬ chung-detecting means are illustrated. The deviation determination device 60a of FIG. 2a comprises a correlator 62 having a first input 64a for receiving the excitation signal and a second input 65a for detecting the reaction signal. The correlator 62 further comprises an output 66a, which outputs the correlation result of the reaction signal and the excitation signal, preferably to the nachge ^¬ switched imaging device 70. The correlation result at the output 66a forms the deviation. In the input 64a, 65a and / or in the output 66a filters may be provided, which are shown in Figure 2 as dashed rectangles. These filters are preferably low pass or band pass filters. In one exemplary embodiment, the low-pass filters have a cut-off frequency of 10, 20, 50 or even 100, 150, 200, 250 or 300 Hz. Furthermore, the cut-off frequency can be 500, 1000, 5000, 10000 or even 100 or 200 or even 500 kHz. The upper limit of the bandpass filter may correspond to the cutoff frequency of the lowpass filter and the lower cutoff frequency of the bandpass filter may or may not be 0.5 Hz, 1 Hz, 2 Hz, 5 Hz, 10 Hz, 20 Hz, 30 Hz or 40 Hz in an exemplary embodiment at 50 Hz, 100 Hz, 200 Hz, 500 Hz, 1 kHz, or even at 2 kHz, 5 kHz, 10 kHz, 50 kHz or 100 kHz. The cutoff frequencies are adapted to the ion mobility in the cell or at the electrodes and are preferably selected such that changes in the reaction signal that reflect a relaxation process under normal conditions (such as cell temperature 20 ° C.) have a frequency spectrum which is at least to 10%, 20%, 50% or 80% fall within the passband of the filter. The cutoff frequencies and the time periods and spectra specified here must be adapted to the ion mobilities that lie in a temperature measurement window for the respective cell type. Another embodiment of a deviation-Discovery ^¬ device 60b with a subtractor 62b which has two inputs 64b, 65b. The Reakti ^¬ onssignal and the excitation signal applied to the said inputs. The subtracter 62b forms the difference between these two signals and outputs the difference to an integrator 66b. The integrator 66b integrates the difference between the excitation signal and the Refe rence ^¬ signal and outputs the third signal as a deviation in the form of a signal or a value from. There may be provided filters and / or damping or reinforcing elements, which are shown in Figure 2b with dashed rectangles. For example, at least one of the inputs 64b, 65b may include an attenuation circuit or an amplification circuit to equalize the levels of the two signals before they are delivered to the subtractor 62b. Finally, a filter may be provided between the subtractor 62b and the integrator 66b and / or a damping element. If at least one of the dashed rectangles shown in FIG. 2b is provided as a filter, then this filter has properties such as the filters shown in FIG. 2a. Subtractor 62b subtracts the response signal from the excitation signal, or vice versa. 66b of the integrator is preferably reset when the deviation from ^¬ been fully determined or when the temperature was ^¬ turwert provided by applying the dependence.

Figure 2c shows another possible deviation-Discovery ^¬ device 60c 62c with a skew-sensing device. This has two inputs 64c, 65c, to which the excitation signal and the reaction signal are applied. Instead of the excitation signal, it is also possible to apply a trigger signal which reproduces at least one time of the occurrence of an edge or a change in the excitation signal. 62c may be provided in the Zeitver ^¬ rate detecting device, a counter and a clock generator which determines the time offset based on a count value. 62c purpose, the time offset-detection device ^¬ a unit with which the occurrence time of the response signal and in particular the time of occurrence of a certain amplitude or slope, or a Zeitsig- Nalverlaufs the reaction signal can be detected. In ^¬ example, a certain course can be compared with the reaction signal by means of a match filter or the like. The skew detection device 62c has an output 66c at which a value is output or a signal representing the time lag between the excitation signal and the response signal. Instead of the excitation signal, in the embodiments described here, a trigger signal may be provided which represents a time of occurrence of a change in the excitation signal, or which may be a time of a

Switching command or change command, this command driving a load supplied by the cells. Since the drive leads to the change in the load, which in turn results in a change in the output of the cells current, the command is a time information of the excitation signal again. Here, the excitation signal is generated by the varying load, so that the occurrence of the command directly Anre ^¬ supply signal. The timing of the command reflects the change that defines the excitation signal. Optionally, a previously known time offset between occurrence of the command and the resulting load change is taken into account in determining the deviation of the reaction signal from the excitation signal. 2b shows a further deviation detecting apparatus 60b, which can be considered as a specific embodiment of the deviation ^¬ chung-determining device 60c of Figure 2c. The excitation signal is input via a first input 64d. Instead of the excitation signal can also be

Trigger signal or a timing signal may be provided that reflects the time of the occurrence of the excitation signal. In principle, the signal difference determination device 60d can also be clocked, so that the input 64d, as shown in FIG. 2, can be dispensed with. The deviation-determining device 60d of FIG. 2d further comprises a comparator 62d with an amplitude limit value 63d. If the amplitude limit 63d is not a property of the comparator 62d or is stored in this, this can in one Memory cell to be stored, which is connected to the comparator. The latter possibility is shown in Figure 2d with ge ^¬ dot broken line. A time offset detection device 64d detects the time difference between the exit time of the excitation signal, cf. optional input 64d, at the time the comparator 62d detects that the threshold 63d has been exceeded or undershot by the response signal. The detected time difference is output as a signal difference at an output 66d.

In an alternative embodiment, the deviation determination device 60d illustrated in FIG. 2d comprises further comparators 62d 62d ^xx with associated threshold values 63d 63d ^xx . The threshold values 63d ^x and 63d ^xx differ from each other and from the threshold value 63d. Also the

Detect comparators 62d ^x and 62d ^xx when the reaction signal, which is present at the input 65d of the deviation determining device 60d, exceeds or falls below the respective threshold value 63d 63d ^xx .

The deviation detection means may comprise a comparator 62d, two comparators 62d and 62d ^x or a plurality of comparators. By means of the one or more comparators is detected when a certain amplitude value or range of the reaction signal is reached, so that these times reflect characteristics of the waveform of the reaction signal. Since the course of the excitation signal predetermined or known to the ex ^¬ deviation detection device must be supplied this does not necessarily. Rather, the response signal is already the deviation to ^¬ excitation signal, so that the reaction signal may reflect the difference or deviation of the response signal relative to the excitation signal again alone against the. The deviation with respect to the excitation signal contained in other words, already in the reaction signal since the response signal based on the Anre ^¬ acceleration signal and beyond (in accordance with the to be detected electrochemical cell properties such as the ion mobility at the electrodes), which reflect the temperature, has deviations.

The skew detection device 64d preferably outputs, for each comparator, a time value or a time signal which indicates when the comparator has detected the overshoot or undershoot of the associated threshold value. The per ^¬ stays awhile time offset is output from the output 66d or other outputs, as shown in Figure 2b by dashed lines. The further optional time outputs, which are shown in dashed lines, are merely illustrative of the basic approach and do not represent physical implementation. Preferably, gives the time offset-detection ^¬ device 64d all time offset values on the same line or on the same channel.

In the case of several comparators, a dependence of the signal difference (that is to say the time offset) for each comparator and / or comparator can be determined. for each threshold a temperature value can be assigned.

Here, the dependency can be multi-dimensional and provide for each comparator its own sub-dependence between time offset and temperature. Furthermore, the skew detection device 64b may output at least one skew between at least two comparators as a signal difference. As already mentioned, for each of the signal differences one can

Dependence be provided. The temperatures resulting for the various dependencies can be combined with one another, for example by selection or averaging, in particular by weighted averaging or also by median formation. Further, in the use of a plurality of deviations, a set of several variations may be associated with only one temperature value, so that the dependence has a more ^¬ dimensional input variable and having the individual temperature only a single output size.

FIGS. 2a-d show deviation detection devices which operate in the time domain. FIGS. 3 a and 3 b show deviation determination devices that are active in the frequency domain. BEITEN. This shows that the reaction signal in the time domain and equally in the frequency domain can be processed according to the invention. The illustrated in Figure 3a deviation detecting means comprises two inputs 60e and 64e 65e, one for the Reakti ^¬ onssignal and one for the excitation signal. The input for the excitation signal is optional and therefore shown in dashed lines. The signal difference detection means 60e includes a spectrum analyzer which converts the response signal at the input 65e or frequency components thereof into the frequency domain. A spectrum comparator 63e downstream of the spectrum analyzer 62e and determines spectral differences to the on ^¬ excitation signal. For this purpose, the excitation signal can be applied to the spectrum comparator 63e at an input 64e. Alternatively, the information about the spectrum of the excitation signal is already present in the signal difference detecting means 60e, and only spectral information of the response signal is evaluated against predetermined values (representing the excitation signal). To this end, the spectrum comparator 63e compares individual frequency components or a frequency range of the spectrum as provided by the spectrum analyzer 62e with known values. It can be the entire spectrum of the reaction signal in the

Spectrum comparator 63e are used for the evaluation. Alternatively, only individual frequencies or at least one frequency range of the reaction signal from the spectrum comparator 63e are used for the evaluation. It can be used a frequency range for the reaction signal and possibly also for the excitation signal. Further, two or more frequencies or frequency ranges may be used for evaluation (i.e., for detecting the deviation).

If the excitation signal 64e is supplied to the spectrum comparator 63e, then a filter may be provided in the input 64e, which is shown as a dashed rectangle in FIG. 3a. The filter may have the properties of the filters, as shown in Figures 2a - 2d. The filter can also Have attenuation or gain characteristics to match the level of the excitation signal to the level of the response signal. These properties can be combined with the properties of one of the filters described here. Furthermore, a corresponding filter may precede the spectral analyzer 62e. The spectral analyzer may be configured as a device configured to perform a Fourier transformation. In a simple case, the spectrum comparator 63e is a band-pass or has the behavior of a plurality of band-pass filters with different cut-off frequencies or frequency ranges passage, so as to use one frequency or frequency ^¬ components from the reaction signal for detection. The level of the response signal is used by the spectrum comparator 63e, which results for the individual frequency bands of the filter. If a filter is used as the spectrum analyzer 62e, it has a bandpass characteristic with a lower cut-off frequency, as mentioned above, and an upper cutoff frequency, as also mentioned for the filters of FIGS. 2a-d. The width of the bandpass (defined by a drop in performance by a power loss of 1 / V2 of the maximum gain of the filter) may also be narrowed, for example, with a width of 5, 10, 20 or 100 Hz between the upper and lower cutoff frequencies. In the

Using narrower bandpasses having a width of less than 50 or 20 Hz, multiple passbands may be provided. During at least one spectral component in the reaction signal is employed in the Figure 3a of the spectrum comparator with respect to a corresponding portion in the excitation signal, is shown in FIG 3b, one approach in which spectral components in ^¬ nerhalb be set the response signal in relation to each other to provide the deviation. While in FIG. 3a spectrum comparator 63e outputs a ratio or difference between frequency components of the excitation signal and the response signal as a deviation, in FIG. 3b approach used as deviation a ratio or a difference of different signal components (ie at different frequencies) of the reaction signal. The deviation determination device 60f illustrated in FIG. 3b comprises a spectral analyzer 62f, which may be configured like the spectral analyzer shown in FIG. 3a. The deviation determination device 60f illustrated in FIG. 3b comprises a spectral analyzer 60f which reproduces the power of the reaction signal in this frequency range or for these frequencies for at least two frequencies or frequency ranges f1, f2. The multiple outputs of the spectral analyzer 62f thus represent different levels, each representing the signal strength for certain frequencies fl, f2 or for certain frequency ranges. These levels can be labeled A and B.

In a spectrum comparator 63f, which is connected downstream of the spectrum analyzer 62f, the levels of different frequencies Fl, F2 or different frequency range are related to each other, for example by a ratio formation or by a difference. The resulting comparison value of the spectrum comparator 63f is output at an output of the signal difference detecting means 60f as a deviation. Previously, the comparison result of

Spectrum comparator 63f may also be compared to a predetermined value (i.e., to a reference) or to a corresponding comparison value that results for the excitation signal, see spectral analyzer and spectrum comparator of Figure 3b, shown in dashed line. A difference generator 64f detects the difference between the ratio of the frequency components of the response signal and the corresponding ratio for the excitation signal. For multiple frequencies or frequency ranges, several differences can be determined. The differences can be as

Deviation between the reaction ^signal and the excitation ^signal can be used. As already noted, the relevant values for the excitation signal can be predetermined, since this is generated according to specifications and is thus known. Compared to the spectral analyzer 62e of FIG. 3a, the spectrum analyzer 62f of FIG. 3b outputs values for a plurality of frequencies or frequency ranges

Deviations, and is designed for example as a bandpass with multiple passbands.

FIGS. 4a-4g show embodiments for signal generators and the associated excitation signals for the generation of which the relevant signal generators are designed. The signal generator 40a generates a single voltage or current jump. This may be directed downward or upward ge ^¬ directed. Further, it may extend from a zero level to a certain positive level or to a negative level. In specific embodiments, the signal generated by the signal generator 40a extends from a negative to a positive level, which may in particular be symmetrical to the zero line. In the simplest case, however, the signal generator 40a is set up to generate a first level of zero and a positive level or also a negative level.

The signal generator 40a can be active and therefore represent its own current or voltage source, or can be passive, for example in the form of a switchable resistor or in the form of a variable resistor, for example in the form of the passage resistance of a transistor. The signal generator 40a preferably comprises a driver circuit or an end stage device, wherein the output stage device can be identical to the unit which generates the signal form. The signal generator of FIG. 4a particularly preferably corresponds to a unit which can be used to generate a compensation current for at least one cell.

The signal generator of Figure 4b with the reference numeral 40b generates a sequence of voltage or current jumps as an excitation signal. These can in terms of their amplitude be turned off, such as the voltage or current jumps generated by the signal generator 40a. Preferably, all voltage jumps generated by the signal generator 40b have the same upper and lower level (or amplitude value). The signal generators 40a and 40b are arranged in simple embodiments only to bring about two different levels, wherein one of these levels can be zero. Also, the signal generator 40b may be configured active or passive, wherein in the case of passive embodiment, a switchable resistor may be provided as a signal generator. This is also true for other signal generators that produce only a variable or switchable current that leads away from the cell. FIG. 4c shows a signal generator 40c which generates an ascending edge as an excitation signal, in which case the amplitude does not jump as fast as possible from a lower value to an upper value, but instead generates a targeted progression. This can be caused for example by a low-pass filtering, for example with a

Cutoff frequency of 100, 150, 200 or 300 Hz. In particular, the signal generator 40c may be provided with a switching element and a filter. The signal generator 40c generates a single pulse per detection step, but may also be modified to generate a plurality of signal pulses per detection step, such as the signal generator 40b.

40c may The waveform of the signal generator of the pulse ^¬ response of a low-pass filter first, second or higher order, respectively. The signal generator 40d of Figure 4d is arranged to generate only a single pulse per detection step, like the signal generators 40a and 40c. The signal generator 40d is provided for generating a single triangular pulse, for example a symmetrical triangular pulse or also an asymmetric sawtooth pulse. Again, the signal may start from a zero level, or may be shifted in the amplitude direction with respect to the time axis. The slope or Slopes of the pulse generated by the signal generator 40d include Spectrum whose power is at least 30, 50, 80 or 90% within a given frequency range. The frequency range in an exemplary embodiment has a lower limit of 0.1, 0.5, 1, 2, 5, 10, 20, 30, 50, 100, 200 or 500 Hz or even 1 kHz, 2kHz, 5 kHz or 10 kHz and a upper limit of 10, 20, 30, 50, 100, 200, 500 Hz or even 1 kHz, 2kHz, 5 kHz, 10 kHz, 20 kHz, 50 kHz, 100 kHz, 200 kHz or 500 kHz. An exemplary embodiment provides a lower limit of 10, 20, 30, 40, 50 or 80 Hz and an upper limit of 120, 150, 180, 200, 250, 300, 350 or 400 Hz or even 600, 800 or 1200 Hz For example, depending on the cell type, the state of charge, a desired temperature span and / or the aging of the cell. The limits are preferably matched to the relaxation rate that results from the cell type. The relaxation may be dependent on the Ionenmo ^¬ bility. , Possibly. For example, the signal generator may include a bandpass or low pass filter (as shown in Figures 2a-d) to filter the generated signal before the output frequency. The signal generated by such a filter has a spectrum as mentioned above.

FIG. 4e shows a further signal generator 40e, which generates a value- and / or time-discrete signal. It is a feedback shift register (only schematically indicated in FIG. 4e), which generates several pulses per determination step, in particular a multiplicity of pulses. The signal generator may 40e generate a number of pulses corresponding to at least the periodicity of the feedback shift register per Determined ^¬ treatment step. The feedback shift register may be followed by a puncturing / padding device, which suppresses a pulse too close to a preceding pulse, or which adds a pulse if too much time has elapsed since the previous pulse or since the last past edge , This ensures that two consecutive edges are at least 0.5 ms apart and not more than 25 ms apart. This allows the spectrum of the excitation signal suitable for temperature detection of cells. Further, the spectrum may be adjusted by providing the signal generator 40e with a bandpass or low pass filter, as described herein. The Sig ^¬ nalgenerator 40e generates a binary signal, ie a signal with exactly two different levels, apart from short and therefore negligible transition phases. However, the signal generator can basically also generate a ternary signal instead of a binary signal. For the edges of the ternary signal, the same conditions arise as for the signal described here, which is generated by the signal generator 40e.

FIG. 4f shows a signal generator 40f configured to generate a signal sequence, in particular a series of direct pulses. The time interval between the individual

Pulses may be constant or may be at least 0.5 ms and not more than 25 ms. The signal sequence can be generated by retrieving a list of values representing the exit times of the respective pulses, this list being read cyclically. The pulse generator may be followed by a low pass or a bandpass having the characteristics of the filters, as shown in Figures 2a - 2d. Instead of a low-pass or band pass, a puncturing / padding device may be provided, as described here. This can be represented by the right, inner rectangle of Figure 40f, which is nachge ^¬ switched to the left inner rectangle of the figure. The left inner rectangle may be a pulse generator that generates pulses as described above. The pulse generator can generate pulses, some of which are not more than 0, 5 ms and / or more than 25 ms apart, the filter and in particular the puncturing / Paddingeinrichtung the

Spectrum of the generated signal changes again to output the Anre ^¬ supply signal. The signal generator 40g of FIG. 4g generates a signal having an upper limit frequency fg. The spectrum is distributed continuously. Within the spectrum, two frequency ranges 41a, b can be provided, which are also used for evaluating the reaction time. be used onssignals. Another alternative signal of the signal generator 40g comprises a spectrum 42 that up to the upper limit frequency fg ^λ extends from a former, the lower limit frequency fu. The spectrum 42 extends at least 10, 20 or 25 Hz up to a maximum of 150, 200 or 300 Hz. The spectra can be generated in particular by bandpass filtering or low-pass filtering. As an output signal a noise signal can be used, in particular a wertkontinu ^¬ ierliches noise signal that low pass or band-pass filtered in order to reach one of the spectra, as represented by Figure 4g. The respective low pass or bandpass has a transfer function which corresponds to one of the spectra shown in FIG. 40g. FIG. 5 shows several dependencies 100, 110, 120 between a deviation and the temperature. The dependencies 100, 110 are exemplary of several different cell types, but the dependencies 100 and 110 may be set for different charge states or aging states (or other properties) of the battery. The dependency 120 is discrete in value, in contrast to the continuous value dependencies 100, 110, and comprises several areas in which a constant temperature is provided for certain of the signal differences. The dependency 120 may be deposited by a number of values wl, w2, etc. which certain individual Tempera ^¬ turwerte are compared. In this case, the dependency 120 in the direction of the temperature axis can have equidistant temperature values, which are each compared with a value w of the signal difference. The temperature interval can be, for example, 0.1, 0.5, 1, 2 or 5 Kelvin.

The deviations applied individually on the abscissa are shown below one another at the end of the abscissa in FIG. In principle, the deviations can reproduce a difference value between a detected excitation signal and a detected reaction signal. Alternatively, however, the excitation signal is known and thus also the relevant reference for the reaction signal. Therefore, instead of the excitation signal a known value, such as a predefined reference, can be used to form the deviation. Furthermore, the excitation signal may already be present in the reaction signal, for example if the spectrum of the reaction signal is considered, which is based on the spectrum of the excitation signal and is changed by the cell (s). A value that reflects a property of only the reaction signal can be regarded as a deviation since the time profile and the spectrum of the reaction signal are fundamentally based on the excitation signal.

The deviation can be provided as a time shift τ, which results from correlation of the reaction signal with the excitation signal. In this case, the quantity τ is the time shift at which a specific feature occurs in the cross-correlation signal of the excitation and the reaction ^signal , for example a peak or a maximum. The deviation thus relates to a correlation result. Instead of being correlated with the on ^¬ excitation signal, the response signal can be correlated with a predefined reference. The reference may be constant for a given dependency, with different, preferably constant Refe ^¬ narrow be used at more than a function or a multidimensional dependence. The reference may change with the cell type, state of charge, aging condition of the battery or cell (or for different cell types or cell designs). Cell designs may be defined by a nominal capacitance, a rated peak output current, rated peak charging current, a rated continuous output current, a rated continuous charging current, a

Nominal internal resistance, a nominal temperature range, by a nominal temperature limit, by an application range and / or by a nominal output voltage. For the relationship of these quantities to the reference, an imaging function between at least one of these quantities and the reference can be specified.

The deviation may also be a time offset At between the excitation signal and the associated response signal. Such a time offset Δt can be detected by detection the time that elapses between the beginning or an edge of the excitation signal and the beginning or an edge of the Reakti ^¬ onssignals. For example, to detect the beginning of the response signal, a special filter may be used (for example, a matched filter arranged to detect the edge) or a comparator included in the

Exceeding or falling below a threshold assumes that at this time the reaction signal starts or has an edge.

Furthermore, the deviation can be represented by a time offset ΔΤ1, which represents a time offset between the current of the excitation signal and the crossing of the at least one threshold value by the reaction signal. In this case, a plurality of values may be provided as a time offset if a plurality of threshold values are predetermined, for example, a first time offset ΔΤ1, which until crossing a first time offset ΔΤ1

Threshold elapses, and a time offset ΔΤ2, which passes until crossing another, to different threshold. The values ΔΤ1 and ΔΤ2 etc. can be combined at a single time offset, for example by weighted averaging or median formation, to be applied to the dependence. Instead, however, it is also possible to provide a plurality of dependencies, preferably a dependency for each threshold value, such as a plurality of values corresponding to a respective one

Time offset of an individual threshold reflect, allocate an associated dependence and each achieve a Tempe ^¬ raturwert per dependency. The respective Tem ^¬ peraturwerte are to be regarded as intermediate values and can also be combined into a temperature value as the output size again. The combination can be provided by (possibly weighted) averaging or median formation.

The deviation may also be provided by integrating the area of the reaction signal, in particular the area from

Jump of the excitation signal or from the exceeding or falling below a threshold value until reaching a further threshold ^¬ value. Such an area gives the power ΔΡ under the Time course again and can be considered as a deviation, especially when the excitation signal has a jump, which also leads (integrable) course of the resulting reaction signal. This power can be considered ΔΡ. Furthermore, a power for a frequency range can be selected, whereby this power can be referred to as ΔΡ. Alternatively, the power ΔΡ is related to a power representing the power of the excitation signal so that ΔΡ can be a ratio value and therefore represented dimensionless.

Another possibility is the consideration of the reaction ^signal or the excitation signal in the frequency domain. Here, the signal difference may be the ratio between the magnitude of a frequency component in the excitation signal Sa for a frequency f1 relative to a signal strength Sr of the response signal for the same frequency f1. Instead of individual frequencies f1 and frequency ranges can be used. The resulting deviation can be represented by Sa (fl) / Sr (fl), wherein Sa is the signal strength or level of strength or power of the on ^¬ excitation signal for the frequency fl, and Sr, the corresponding signal strength or power of the response signal for the same Frequency f1. Based on the corresponding dependency, the reciprocal Sr / Sa can also be used. If the signal strengths are used for a frequency range, Sa and Sr refer to the same frequency range.

Finally, the deviation can be determined by detecting the level difference of frequency components of the reaction signal, wherein the frequency components relate to different fre ^¬ frequencies or frequency ranges. In the same way, the level difference of frequency components of the excitation signal can also be detected or predetermined. The deviation results from the comparison, ie by a ratio formation or a difference formation of the level difference, which results for the reaction signal, based on the level difference, which is for the excitation signal, wherein for the excitation signal, the same frequencies or frequency ranges be used. The ratio of the levels for different frequency components of the respective signals partially reflects their spectrum, so that changes in this spectrum can be directly deduced from the temperature. Finally, a slope can be used as a deviation, either a gradient course or a slope at at least one specific time, which results, for example, from a specific predetermined amplitude value of the reaction signal. The slope for a specific time tl of the reaction signal sr (t) (in the time ^{¬ range} ) is derived according to the time, so that sr (t) / dt results. It can be used as a signal difference of the time course of this derivative, the slope at certain times or only at a certain time tl. When using the time course of the slope, this can be compared with a predetermined course, the comparison result to the given course reflects the deviation. In this case, the deviation is determined on the basis of the time profile, but not on the basis of the course of the reaction signal itself, but on the basis of the profile of the slope of the reaction signal. If the slope is used at a certain time tl, then results in a particularly simple evaluation. This time may be a predetermined time, for example, a time of a predetermined period of time after the beginning or after

Occurrence of a jump in the excitation signal. Furthermore, this time t1 can also reflect a time at which the reaction signal passes a certain predetermined threshold. In particular, t1 may occur at the beginning of an edge of the response signal at which the relaxation response of the at least one cell begins, or the time t1 may be provided at a time when the relaxation response has already advanced to a certain degree, such as a component of the relaxation response to capture, which has a greater time constant than other components of the relaxation ^¬ onsantwort. FIG. 6 can be used to obtain an example of the relaxation response with respect to the deviation. Figure 6 shows the time course of a reaction signal sr (t), giving the basic principle of relaxing response ^¬ again. Curves 200-230 show different relaxation responses for different relaxation time constants. The time constants are plotted for the curves 200, 210 and 230 on the right side of the diagram. The curve 200 corresponds to the sum of the curves 200 and 210, normalized by the factor 0.5.

The slope line 212 of the curve 210 and the slope line 202 of the curve 200 at the time t 1 represent different speeds of relaxation. A larger slope means a higher temperature here. Either the slope of the straight lines 202 and / or 212 can be used as a deviation, or their intersection with the t-axis can be used, since this also reflects the time constant of the relaxation. The area 250 represents the integral of the curve 210 for a period of time 252. This surface 250 alone can be used as a deviation, in particular since a falling current of the excitation signal was used for the excitation, which is reflected in the reaction signals. Furthermore, an area 260 may be provided which integrates the curve 210 after the time t for a further time period 262. Also, this surface 260 can be used alone as a signal difference. In particular, however, the ratio of the surfaces 252-262 can also be used. It should be noted that in FIG. 6 the time intervals 262 and 252 do not overlap and in particular are temporally spaced apart. For example, in an imaginary comparison with ent ^¬ speaking surfaces of the curve 200 is immediately apparent that there are other values in both the single value consideration as well as the ratio of viewing, so it is clear that the temperature may result directly from these quantities. Further, reference is made to a comparison of curves 230 and 220, where curve 230 represents a single time constant, and curve 220 represents the sum of two relaxation responses having different time constants (0,1, 0,3). If the gradients are detected at different times, in this case t2 and t3, it is directly apparent that the gradients (shown by a dotted line) at the time t2 differ in a different way than at the time t3. While at the time t2 small time constants dominate dominate at the time t3, which is significantly after the time t2, larger time ^¬ constant. Since the different time constants of the same reaction signal can be attributed to different locations of the cell, for example the anode and the cathode, a deviation value can be detected in each case by observing the slope at different times. Each of these values may be assigned to an individual temperature value according to the method described herein. This results in so different temperature values for different ^¬ sector organizations throughout within the cell. From the comparison of the slopes shown here, it can be seen that the curve 230, which has only one time constant (0.14), drops in some other way than the curve 230 with a plurality of time constants, whereby the detection of different relaxation components within the same reaction signal from FIG. 6 can be seen ,

Embodiments are described herein that are not limited to the embodiments shown in the figures and which provide that the deviation is determined on the basis of the reaction signal or on the basis of the reaction signal and the excitation signal, in particular on the basis of a comparison of FIG

Reaction signal with an excitation signal, for example with the excitation signal that was used to generate the response signal. In addition, another, given Anre ^¬ acceleration signal can be used for comparison. In particular, a determination based on a signal comprises a determination on the basis of at least one property of the signal, in particular of a property which characterizes the course or the time of occurrence of the signal. It can all the properties that the Or only all properties which characterize the course, but only individual properties, or only one property such as a slope at a predetermined amplitude value or time or the time of occurrence of one or more amplitude values is determined Deviation used.

Instead of detecting a deviation of the response signal relative to the excitation signal, this has generated only the response signal can be analyzed, because the reaction ^¬ signal ((a response of the cell n) to the excitation signal) already has characteristics of the excitation signal, in addition to the egg ^¬ properties that result from the signal response of the cell (s).

Furthermore, the deviation of the reaction signal from a predetermined reference (such as a reference reaction signal) can be considered. The reference corresponds to a standard reaction signal that results in a cell under normal conditions, the deviation from this standard being used to provide or determine the temperature value of the cell (s). Since that

Naturally includes standard response signal in addition to the response of a cell at Nor ^¬ Grinding Conditions and properties of the associated excitation signal which is the reference based on (or with which this has been generated) corresponding to the comparison of the detected response signal relative to the reference a comparison of the response signal relative to a response signal. The excitation signal on which the reference is based exhibits intrinsic properties of the excitation signal which is applied to the cell (s) for determining the temperature value. The Normalbe ^¬ conditions include a predetermined temperature value (about 10 ° C 20 ° C, 40 ° C, 60 ° C) and / or other parameters of the cell in question, such as the cell type, the state of charge and / or the aging state of the cell and / or at least one size of the cell design described herein. The reference preferably refers to the same cell type, which also corresponds to the cell whose temperature is detected. Different references can be used for different cell types, aging states, states of charge or for other parameters of the cell (for example at least one size of the cell design described here). The reference or references can be obtained from empirical studies, electrochemical or electrical models or simulations, which preferably relate to the cell type (furthermore: aging state or state of charge or another size of the cell design described here), which the cell also has, its temperature value is detected. According to an embodiment, the cell whose temperature value is to be detected is excited with an excitation signal to obtain the reference. This can then be stored, for example in a memory of the determination device, and used for future determinations of the temperature, in particular for determining the deviation. The reference can furthermore be corrected before the deviation is determined, depending on deviations of the cell from at least one parameter of the standard conditions. A dependency may be provided that associates at least one correction value used for correction with one or more deviations in at least one parameter defining the normal condition. This dependence, which is used for the correction, can also be determined empirically or by means of models or simulations. Parameters defining the normal condition or the cell, for example, cell type, in particular the cell ^¬ chemistry, aging status, charging status, capacity or other variables which define the cell design as described herein. Reference sign list

10 at least one cell

12 a, b power bus

20 battery

30 investigative device

40, 40a-g signal generator

41a, b; Af frequency bands

fu, fg, fg ^x lower, upper limit frequency

S (f) spectrum of the reaction signal

42 Spectrum of the signal generator

50 reaction signal detecting means

60, 60a-f signal difference detecting means

62a correlator

62b subtractor

66b integrator

62c, 64d time offset detection device

62d, 62d \ 62d ^xx comparator

63d, 63d \ 63d ^xx Amplitude limit

62e, 62f spectral analyzer

63e, 63f spectrum comparator

64f subtractor

70 imaging device

80 output interface

90 charge balancing device

92 power amplifier device

93 charge equalization control unit

96 evaluation device

97 comparators

98 temperature limit

99 current limiting device

100, 110, 120 dependencies between temperature and

signal difference

200-230, sr (t) response signal over time t

250, 260 temporal integrals of the reaction signal 252, 262 time intervals for integration of the reaction signal

S cL ScL excitation signal

sr, Sr reaction signal

Claims

Patent claims

1. Method for determining a temperature (ü) of at least one cell (10) of a battery (20), with the steps: applying an excitation signal (sa) to the cell (10); detecting a response signal (sr) generated in the cell (10) by the application;

Determining a deviation between the excitation signal (sa) and the reaction signal (sr); and

Determining a temperature value that reflects the temperature (ü) by applying a predetermined dependency (100 - 120) typical for the cell between ^{corresponding} deviations and associated temperature values to the determined deviation, where

the excitation signal (sa) has several discretely or ^continuously distributed different frequency components and the response signal (sr) represents the signal response of the at least one cell (10) to the response signal (sr).

2. The method according to claim 1, wherein the excitation signal (sa) has at least one jump and the reaction signal (sr) represents the signal response to this at least one jump.

3. The method according to claim 1 or 2, wherein the deviation relates to a single edge of the excitation signal (sa) and the response signal (sr) represents a relaxation response of the at least one cell (10), or wherein the deviation relates to a binary signal Excitation signal (sa) refers and wherein the step of applying the excitation signal (sa), the step of detecting the ^reaction signal (sr) and / or the step of determining the signal difference is a step of low-pass ^or band-pass ^filtering of the signal in question the deviation includes.

Method according to one of the preceding claims, wherein the deviation relates to an excitation signal (sa) provided as a binary signal and the binary signal is a noise signal, in particular a pseudo-noise signal, and furthermore at least 50%, 70%, 80% or 90% of all time ^intervals between two consecutive edges of the binary signal is at least 0.1 ms, 0.2 ms, 0.5 ms or 1 ms and not more than 10 ms, 15 ms, 20 ms, 25 ms, 30 ms or 40 ms, the time distance between two edges preferably being from Cell type and/or a predetermined temperature measurement window depends.

Method according to one of the preceding claims, wherein

(a) the deviation is determined by cross-correlation (62a) of the excitation signal (sa) and the associated response signal (sr), and the correlation result of the cross-correlation is used as the deviation in the step of providing the temperature value; or where

(b) the deviation is determined by detecting a time ^offset (At) between the excitation signal (sa) and the associated response signal (sr), and the time offset (At) is used as a deviation in the step of providing the temperature value; or where

(c) the deviation is determined by comparing the reaction signal (sr) with one, two or more threshold values, the at least one time offset between the excitation signal and the crossing of the at least threshold value by the associated reaction ^signal being used as the deviation; or where

(d) the deviation is determined by integrating the area (252) of the reaction signal from the time of a jump in the excitation signal or from the time when the reaction signal crosses a predefined threshold value and the area is used as the deviation in the step of providing the temperature value.

Method according to one of claims 1 - 4, wherein the deviation is determined by comparing a level of at least one frequency component (Sr (fl)) of the reaction ^signal with a level of at least one frequency ^component (Sa (fl)) of the excitation signal of the same frequency (fl), and the deviation from the result of the ^comparison is reproduced; or

the deviation is determined by detecting the level ^difference of frequency components of the response ^signal whose frequencies (fl; f2) are different, and by comparing the level difference with a ^{corresponding} level difference of the frequency components of these frequencies (fl; f2) in the excitation signal.

Method according to one of the preceding claims, wherein the application comprises: applying the excitation signal via at ^least one line (14), via which at least one compensating current for charge equalization also flows from or to the at least one cell (10).

Method according to claim 7, wherein the excitation signal (sa) is generated by means of an output stage device (92), which also generates the compensating current for charge equalization of the at least one cell (10).

Determination device (30) for determining a temperature of at least one cell (10) of a battery (20), comprising:

a signal generator (40) set up to generate an excitation signal (sa; Sa) which has a plurality of discretely or continuously distributed different frequency components;

a response signal detection device (50) arranged to detect a response signal (sr; Sr) generated by the cell (10);

a deviation determination device (60) set up to determine a deviation of the reaction signal compared to the excitation signal; an imaging device (70), which is connected downstream of the signal ^difference determination device (60), and which is equipped with at least one predetermined dependency between ^{corresponding} dependencies and associated temperatures, which is typical for the at least one cell (10); and

an output interface (80), which is connected downstream of the imaging ^device (70) and is set up to output a ^temperature value.

10. Determination device (30) according to claim 9, further comprising:

a charge compensation device (90) with an output stage device (92) set up to generate a compensation current for the at least one cell (10), the signal generator (40) being connected to the output stage device (92) in a driving manner.

11. Determination device according to claim 9 or 10, which further comprises at least one line (14) or measuring interface via which the at least one cell (10) is connected to the signal generator (40) and to a charge equalization ^device (92).

12. Battery (20) with multiple cells (10), comprising:

a signal generator (40) set up to generate an excitation signal (sa; Sa) which has a plurality of discretely or continuously distributed different frequency components, the signal generator (40) being connected to the cells (10) via lines (14);

a reaction signal detection device (50) set up to detect a reaction signal (sr; Sr) which is generated by the cell (10), the reaction ^signal detection device (50) for detecting the

Response signal is connected to the lines (14); a deviation determination device (60) set up to determine a deviation between the excitation signal (sa, Sa) and the reaction signal (sr, Sr) for all Cells (14), for at least a subgroup of cells or for individual cells; and

an imaging device (70) which is connected downstream of the deviation determination device (60) and which is equipped with at least one predetermined dependency between deviations and temperature values that is typical for the cell; wherein the battery further comprises:

an output interface (80), which is connected downstream of the imaging ^device (70) and is set up to output a ^temperature value, or

an evaluation device (96), which is connected downstream of the imaging device (80) and has a comparator (97) and a temperature limit value (98), the evaluation device (96) being set up to output an error signal, preferably to a current ^limiting device ( 99) of the battery (20) when a temperature value emitted by the imaging device (70) exceeds the temperature limit value (98).

The battery (20) according to claim 12, further comprising: a charge equalizer (90) connected to the cells (10), preferably via the lines (14), the charge equalizer (90) comprising an output stage device (92) which is set up is to generate a compensating current for charge equalization between the cells (10) and the excitation signal (sa, Sa) which is applied to the cells (10).