US20010033972A1 - Lithium ion secondary battery - Google Patents

Lithium ion secondary battery Download PDF

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Publication number
US20010033972A1
US20010033972A1 US09/299,097 US29909799A US2001033972A1 US 20010033972 A1 US20010033972 A1 US 20010033972A1 US 29909799 A US29909799 A US 29909799A US 2001033972 A1 US2001033972 A1 US 2001033972A1
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US
United States
Prior art keywords
lithium ion
active material
secondary battery
ion secondary
power density
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US09/299,097
Inventor
Mikio Kawai
Toyoaki Nakagawa
Hideaki Horie
Yuji Tanjo
Takaaki Abe
Ken Iwai
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Nissan Motor Co Ltd
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Nissan Motor Co Ltd
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Filing date
Publication date
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Assigned to NISSAN MOTOR CO., LTD reassignment NISSAN MOTOR CO., LTD ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: ABE, TAKAAKI, HORIE, HIDEAKI, IWAI, KEN, KAWAI, MIKIO, NAKAGAWA, TOYOAKI, TANJO, YUJI
Publication of US20010033972A1 publication Critical patent/US20010033972A1/en
Abandoned legal-status Critical Current

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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07H—SUGARS; DERIVATIVES THEREOF; NUCLEOSIDES; NUCLEOTIDES; NUCLEIC ACIDS
    • C07H19/00—Compounds containing a hetero ring sharing one ring hetero atom with a saccharide radical; Nucleosides; Mononucleotides; Anhydro-derivatives thereof
    • C07H19/02—Compounds containing a hetero ring sharing one ring hetero atom with a saccharide radical; Nucleosides; Mononucleotides; Anhydro-derivatives thereof sharing nitrogen
    • C07H19/04—Heterocyclic radicals containing only nitrogen atoms as ring hetero atom
    • C07H19/16—Purine radicals
    • C07H19/20—Purine radicals with the saccharide radical esterified by phosphoric or polyphosphoric acids
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07H—SUGARS; DERIVATIVES THEREOF; NUCLEOSIDES; NUCLEOTIDES; NUCLEIC ACIDS
    • C07H19/00—Compounds containing a hetero ring sharing one ring hetero atom with a saccharide radical; Nucleosides; Mononucleotides; Anhydro-derivatives thereof
    • C07H19/02—Compounds containing a hetero ring sharing one ring hetero atom with a saccharide radical; Nucleosides; Mononucleotides; Anhydro-derivatives thereof sharing nitrogen
    • C07H19/04—Heterocyclic radicals containing only nitrogen atoms as ring hetero atom
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K1/00—General methods for the preparation of peptides, i.e. processes for the organic chemical preparation of peptides or proteins of any length
    • C07K1/13—Labelling of peptides

Definitions

  • the present invention relates to a lithium ion secondary battery used in a hybrid vehicle.
  • a lithium ion secondary battery disclosed by Tokkai Hei 5-29022 published in 1993 by the Japanese Patent Office comprises positive/negative electrodes, an active material which performs a reversible electrochemical reaction with lithium ions, and a non-aqueous electrolytic solution which allows lithium ion transport.
  • the lithium ion secondary battery can be repeatedly charged and discharged, and since it is lightweight, it is also used as a battery of a hybrid vehicle.
  • a hybrid vehicle is a vehicle provided with an engine and an electric motor as sources of drive force, and it can run on either or both of these sources.
  • the hybrid vehicle runs on the motor which has a higher performance than the engine in this region, and in the high speed, high load region, it runs on the engine which has a higher performance than the motor in this region.
  • the motor is mainly used during vehicle start, acceleration and deceleration. Therefore, the battery which supplies power to the motor must have a high power density so as to supply a large amount of power in a short time.
  • this invention provides a lithium ion secondary battery comprising a non-aqueous electrolytic solution, and a current collector which is coated with an active material and immersed in the electrolytic solution.
  • the coating thickness of the active material is set to 5-80 ⁇ m.
  • FIG. 1 is a cross sectional view of a lithium ion secondary battery according to this invention.
  • FIG. 2 is an enlarged view of a part A of FIG. 1.
  • FIG. 3 is a diagram showing the relation of the coating thickness of an active material and power density of the lithium ion secondary battery.
  • FIG. 4 is a diagram showing the relation of the particle size of the active material and power density of the lithium ion secondary battery.
  • a lithium ion secondary battery comprises film-like positive electrodes 1 , separators 2 and negative electrode materials 3 which are laminated on each other and immersed in a non-aqueous electrolytic solution 4 .
  • the positive electrode 1 is formed by coating a positive electrode active material 6 on the surface of an aluminum current collector 5
  • a negative electrode 3 is formed by coating a negative electrode active material 8 on the surface of a copper current collector 7 .
  • Carbons such as graphite, mesophase carbon, hard carbon or low temperature burned carbon, metal oxides such as SnB x P y O z , Nb 2 O 5 , LiTi x O y , LiFe x N y and LiMn x N y , or nitrides, are used for the negative electrode active material 8 .
  • FIG. 3 shows the relation of the coating thickness to power density when an active material of 1 ⁇ m particle size is used.
  • the ordinate is relative power density when the power density for a coating thickness of 100 ⁇ m is one.
  • the coating thickness is 100 ⁇ m, the energy density increases but the internal resistance also increases and the interior of the active material no longer contributes to input/output of short-term large currents, therefore, the power density falls.
  • the power density can be enhanced to more than twice its value for a coating thickness of 100 ⁇ m, and if the coating thickness of the active material is 8-60 um, the power density can be further enhanced to about three or more times its value for a coating thickness of 100 ⁇ m.
  • FIG. 4 shows the relation of particle size of the active material to power density.
  • the ordinate is relative power density when the power density for a particle size of 10 ⁇ m is one. It is required that the maximum particle size of the active material does not exceed the coating thickness.
  • the particle size of the active material is 5 ⁇ m, the power density is enhanced to about twice its value for a particle size of 10 ⁇ m. If the particle size is large, diffusion in the active material becomes slower and the power density declines, so to enhance the power density, the particle size should not exceed 5 ⁇ m.
  • the coating thickness of the active materials 6 and 8 is 5-80 ⁇ m and preferably 8-60 ⁇ m, and the particle size of the active materials 6 and 8 is smaller than 5 ⁇ m. As a result, a lithium ion secondary battery of high power density is obtained.

Abstract

A lithium ion secondary battery comprises a non-aqueous electrolytic solution, and a current collector which is coated with an active material and immersed in the electrolytic solution. By setting the coating thickness of said active material 5-80 μm, the power density of the lithium ion secondary battery is improved.

Description

    FIELD OF THE INVENTION
  • The present invention relates to a lithium ion secondary battery used in a hybrid vehicle. [0001]
    • BACKGROUND OF THE INVENTION
  • A lithium ion secondary battery disclosed by Tokkai Hei 5-29022 published in 1993 by the Japanese Patent Office, comprises positive/negative electrodes, an active material which performs a reversible electrochemical reaction with lithium ions, and a non-aqueous electrolytic solution which allows lithium ion transport. [0002]
  • The lithium ion secondary battery can be repeatedly charged and discharged, and since it is lightweight, it is also used as a battery of a hybrid vehicle. A hybrid vehicle is a vehicle provided with an engine and an electric motor as sources of drive force, and it can run on either or both of these sources. [0003]
    • SUMMARY OF THE INVENTION
  • In the low speed, low load region, the hybrid vehicle runs on the motor which has a higher performance than the engine in this region, and in the high speed, high load region, it runs on the engine which has a higher performance than the motor in this region. [0004]
  • The motor is mainly used during vehicle start, acceleration and deceleration. Therefore, the battery which supplies power to the motor must have a high power density so as to supply a large amount of power in a short time. [0005]
  • It is therefore an object of this invention to provide a lithium ion secondary battery of high power density. [0006]
  • In order to achieve the above object, this invention provides a lithium ion secondary battery comprising a non-aqueous electrolytic solution, and a current collector which is coated with an active material and immersed in the electrolytic solution. The coating thickness of the active material is set to 5-80 μm. [0007]
  • The details as well as other features and advantages of this invention are set forth in the remainder of the specification and are shown in the accompanying drawings.[0008]
    • BRIEF DESCRIPTION OF THE DRAWINGS
  • FIG. 1 is a cross sectional view of a lithium ion secondary battery according to this invention. [0009]
  • FIG. 2 is an enlarged view of a part A of FIG. 1. [0010]
  • FIG. 3 is a diagram showing the relation of the coating thickness of an active material and power density of the lithium ion secondary battery. [0011]
  • FIG. 4 is a diagram showing the relation of the particle size of the active material and power density of the lithium ion secondary battery.[0012]
    • DESCRIPTION OF THE PREFERRED EMBODIMENTS
  • Referring to FIG. 1 and FIG. 2 of the drawings, a lithium ion secondary battery comprises film-like positive electrodes [0013] 1, separators 2 and negative electrode materials 3 which are laminated on each other and immersed in a non-aqueous electrolytic solution 4.
  • The positive electrode [0014] 1 is formed by coating a positive electrode active material 6 on the surface of an aluminum current collector 5, and a negative electrode 3 is formed by coating a negative electrode active material 8 on the surface of a copper current collector 7.
  • Here, metal oxides such as LiCoO[0015] 2, LiNiO2, LiMn2O4, LixFeOy and LixVyOz, compound oxides wherein part of these elements are replaced by other elements, e.g., LixCoyMzO2 (M=Mn, Ni, V, etc.) or LixMnyMzO4 (M=Li, NI, Cr, Fe, Co, etc) where the metal element is replaced, or LixMn2O4-aFb and LixCoyNIzOwFa where oxygen is replaced by fluorine, are used for the positive electrode active material 6. Carbons such as graphite, mesophase carbon, hard carbon or low temperature burned carbon, metal oxides such as SnBxPyOz, Nb2O5, LiTixOy, LiFexNy and LiMnxNy, or nitrides, are used for the negative electrode active material 8.
  • FIG. 3 shows the relation of the coating thickness to power density when an active material of 1μm particle size is used. The ordinate is relative power density when the power density for a coating thickness of 100 μm is one. [0016]
  • When the coating thickness is 100 μm, the energy density increases but the internal resistance also increases and the interior of the active material no longer contributes to input/output of short-term large currents, therefore, the power density falls. [0017]
  • On the other hand, if the coating thickness of the active material is 5-80 μm as shown in FIG. 3, the power density can be enhanced to more than twice its value for a coating thickness of 100 μm, and if the coating thickness of the active material is 8-60 um, the power density can be further enhanced to about three or more times its value for a coating thickness of 100 μm. [0018]
  • FIG. 4 shows the relation of particle size of the active material to power density. The ordinate is relative power density when the power density for a particle size of 10μm is one. It is required that the maximum particle size of the active material does not exceed the coating thickness. [0019]
  • As seen from this figure, if the particle size of the active material is 5 μm, the power density is enhanced to about twice its value for a particle size of 10 μm. If the particle size is large, diffusion in the active material becomes slower and the power density declines, so to enhance the power density, the particle size should not exceed 5 μm. [0020]
  • Therefore, in this embodiment, the coating thickness of the [0021] active materials 6 and 8 is 5-80 μm and preferably 8-60 μm, and the particle size of the active materials 6 and 8 is smaller than 5 μm. As a result, a lithium ion secondary battery of high power density is obtained.
  • The entire contents of Japanese Patent Applications P10-133070 (filed May 15, 1998) are incorporated herein by reference. [0022]
  • Although the invention has been described above by reference to certain embodiments of the invention, the invention is not limited to the embodiments described above. The construction and materials of the battery are not limited to the construction and materials of the above-mentioned embodiment. Modifications and variations of the embodiments described above will occur to those skilled in the art, in light of the above teachings. [0023]
  • The scope of the invention is defined with reference to the following claims. [0024]

Claims (3)

What is claimed:
1. A lithium ion secondary battery comprising:
a non-aqueous electrolytic solution, and
a current collector which is coated with an active material and immersed in said electrolytic solution,
wherein the coating thickness of said active material is 5-80 μm.
2. A lithium ion secondary battery as defined in
claim 1
, wherein the coating thickness of said active material is 8-60 μm.
3. A lithium ion secondary battery as defined in
claim 1
, wherein the particle size of said active material is smaller than 5 μm.
US09/299,097 1998-05-15 1999-04-26 Lithium ion secondary battery Abandoned US20010033972A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP10-133170 1998-05-15
JP13317098A JP4240574B2 (en) 1998-05-15 1998-05-15 Protein labeling composition and protein labeling method

Publications (1)

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US09/190,276 Expired - Lifetime US6228994B1 (en) 1998-05-15 1998-11-13 Labeled protein and its producing method, labeling compound to be used in the method, and method for analyzing function of genes
US09/299,097 Abandoned US20010033972A1 (en) 1998-05-15 1999-04-26 Lithium ion secondary battery
US09/737,751 Abandoned US20010039011A1 (en) 1998-05-15 2000-12-18 Labeled protein and its producing method, labeling compound to be used in the method, and method for analyzing function of genes
US09/794,128 Expired - Lifetime US7041446B2 (en) 1998-05-15 2001-02-28 Labeled protein and its producing method, labeling compound to be used in the method, and method for analyzing function of genes

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US09/794,128 Expired - Lifetime US7041446B2 (en) 1998-05-15 2001-02-28 Labeled protein and its producing method, labeling compound to be used in the method, and method for analyzing function of genes

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US6920167B2 (en) 1999-05-27 2005-07-19 Sony Corporation Semiconductor laser device and method for fabricating thereof
US20050233219A1 (en) * 2004-02-06 2005-10-20 Gozdz Antoni S Lithium secondary cell with high charge and discharge rate capability
US20060240290A1 (en) * 2005-04-20 2006-10-26 Holman Richard K High rate pulsed battery
US20070166617A1 (en) * 2004-02-06 2007-07-19 A123 Systems, Inc. Lithium secondary cell with high charge and discharge rate capability and low impedance growth
US7713313B1 (en) * 2006-04-13 2010-05-11 Lithdyne Llc Process for preparing lithium manganate
US7879486B2 (en) 2002-01-15 2011-02-01 Quallion Llc Electric storage battery construction and method of manufacture
US8080329B1 (en) 2004-03-25 2011-12-20 Quallion Llc Uniformly wound battery
US20160380314A1 (en) * 2015-06-25 2016-12-29 Samsung Electronics Co., Ltd. Negative electrode for lithium metal battery and lithium metal battery including the same

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US7433035B2 (en) * 1998-06-29 2008-10-07 San Diego State University Research Foundation Detection of carbon halogen bonds
JP4493125B2 (en) * 1999-05-07 2010-06-30 独立行政法人理化学研究所 Method for detecting interacting proteins
NZ515292A (en) * 1999-07-12 2003-08-29 Phylos Inc Protein with a puromycin tag covalently bonded to the protein's C-terminal
JP3750020B2 (en) * 2000-12-07 2006-03-01 学校法人慶應義塾 C-terminal modified protein and production method thereof, modifying agent and translation template used for production of C-terminal modified protein, and protein interaction detection method using C-terminal modified protein
JP2002257832A (en) * 2001-02-27 2002-09-11 Gencom Co Protein labeling reagent
JP2002253240A (en) * 2001-02-27 2002-09-10 Gencom Co Analysis of intermolecular interaction
WO2003014734A1 (en) * 2001-08-07 2003-02-20 Keio University Method of detecting interaction between substance and protein, method of screening protein interacting with substance, and method of forming complex of substance and protein interacting with the substance
JP4030019B2 (en) * 2001-12-07 2008-01-09 学校法人慶應義塾 Complex of mapping molecule and C-terminal labeled protein, complex of mapping molecule, and protein-protein interaction analysis method using the complex
EP1497303A2 (en) * 2002-04-22 2005-01-19 Joseph F. Lawler Jr. Reagents for monitoring nuclei acid amplification and methods of using same
AU2003231743A1 (en) * 2002-04-23 2003-11-10 California Institute Of Technology Methods for evaluation of in vitro aminoacyl trnaproduction using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry
JP4478772B2 (en) * 2002-12-11 2010-06-09 学校法人慶應義塾 Protein that forms a complex with c-Fos protein, nucleic acid encoding the same, and methods for using them
JPWO2004070371A1 (en) * 2003-02-10 2006-05-25 三菱化学株式会社 Protein NMR measurement method
JPWO2004113530A1 (en) * 2003-06-18 2006-08-03 三菱化学株式会社 Polynucleotide for labeling protein synthesis
JP2006211902A (en) * 2003-07-29 2006-08-17 Mitsubishi Chemicals Corp Method for synthesizing protein having selectively labeled amino acid
JP5587528B2 (en) * 2003-11-19 2014-09-10 国立大学法人 東京大学 Protein that forms a complex with c-Jun protein, nucleic acid encoding the same, and method of using the same
US20060057069A1 (en) * 2004-06-07 2006-03-16 California Institute Of Technology Detection of protein expression in vivo using fluorescent puromycin conjugates
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US7749957B2 (en) 2006-04-06 2010-07-06 E.I. Du Pont De Nemours And Company Clay-binding peptides and methods of use
US7951559B2 (en) * 2007-07-25 2011-05-31 E.I. Du Pont De Nemours And Company Recombinant peptide production using a cross-linkable solubility tag

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Cited By (16)

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Publication number Priority date Publication date Assignee Title
US6920167B2 (en) 1999-05-27 2005-07-19 Sony Corporation Semiconductor laser device and method for fabricating thereof
US7879486B2 (en) 2002-01-15 2011-02-01 Quallion Llc Electric storage battery construction and method of manufacture
US8080338B2 (en) 2004-02-06 2011-12-20 A123 Systems, Inc. Lithium secondary cell with high charge and discharge rate capability
US7799461B2 (en) 2004-02-06 2010-09-21 A123 Systems, Inc. Lithium secondary cell with high charge and discharge rate capability
US20070166617A1 (en) * 2004-02-06 2007-07-19 A123 Systems, Inc. Lithium secondary cell with high charge and discharge rate capability and low impedance growth
US7261979B2 (en) 2004-02-06 2007-08-28 A123 Systems, Inc. Lithium secondary cell with high charge and discharge rate capability
US7348101B2 (en) 2004-02-06 2008-03-25 A123 Systems, Inc. Lithium secondary cell with high charge and discharge rate capability
US20080169790A1 (en) * 2004-02-06 2008-07-17 A123 Systems, Inc. Lithium secondary cell with high charge and discharge rate capability
US9608292B2 (en) 2004-02-06 2017-03-28 A123 Systems Llc Lithium secondary cell with high charge and discharge rate capability and low impedance growth
US8617745B2 (en) 2004-02-06 2013-12-31 A123 Systems Llc Lithium secondary cell with high charge and discharge rate capability and low impedance growth
US20050233220A1 (en) * 2004-02-06 2005-10-20 Gozdz Antoni S Lithium secondary cell with high charge and discharge rate capability
US20050233219A1 (en) * 2004-02-06 2005-10-20 Gozdz Antoni S Lithium secondary cell with high charge and discharge rate capability
US8080329B1 (en) 2004-03-25 2011-12-20 Quallion Llc Uniformly wound battery
US20060240290A1 (en) * 2005-04-20 2006-10-26 Holman Richard K High rate pulsed battery
US7713313B1 (en) * 2006-04-13 2010-05-11 Lithdyne Llc Process for preparing lithium manganate
US20160380314A1 (en) * 2015-06-25 2016-12-29 Samsung Electronics Co., Ltd. Negative electrode for lithium metal battery and lithium metal battery including the same

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US20010039011A1 (en) 2001-11-08
JPH11322781A (en) 1999-11-24
US20010007751A1 (en) 2001-07-12
US6228994B1 (en) 2001-05-08
JP4240574B2 (en) 2009-03-18
US7041446B2 (en) 2006-05-09

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