WO2016084411A1 - Batterie - Google Patents

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Publication number
WO2016084411A1
WO2016084411A1 PCT/JP2015/065413 JP2015065413W WO2016084411A1 WO 2016084411 A1 WO2016084411 A1 WO 2016084411A1 JP 2015065413 W JP2015065413 W JP 2015065413W WO 2016084411 A1 WO2016084411 A1 WO 2016084411A1
Authority
WO
WIPO (PCT)
Prior art keywords
separator
separators
cathode electrode
temperature
electrode
Prior art date
Application number
PCT/JP2015/065413
Other languages
English (en)
Japanese (ja)
Inventor
暁宏 茂出木
Original Assignee
Necエナジーデバイス株式会社
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Necエナジーデバイス株式会社 filed Critical Necエナジーデバイス株式会社
Publication of WO2016084411A1 publication Critical patent/WO2016084411A1/fr

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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00Secondary cells; Manufacture thereof
    • H01M10/05Accumulators with non-aqueous electrolyte
    • H01M10/058Construction or manufacture
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/463Separators, membranes or diaphragms characterised by their shape
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M6/00Primary cells; Manufacture thereof
    • H01M6/02Details
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00Secondary cells; Manufacture thereof
    • H01M10/05Accumulators with non-aqueous electrolyte
    • H01M10/058Construction or manufacture
    • H01M10/0585Construction or manufacture of accumulators having only flat construction elements, i.e. flat positive electrodes, flat negative electrodes and flat separators
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10Energy storage using batteries
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50Manufacturing or production processes characterised by the final manufactured product

Definitions

  • the present invention relates to a battery.
  • a cathode electrode, a separator, and an anode electrode may be stacked.
  • Patent Literature 1 and Patent Literature 2 describe that a cathode electrode or an anode electrode is sandwiched between two separators.
  • a thermoplastic resin is provided between two separators. In this case, the thermoplastic resin is melted by heating the separator. And two separators are mutually affixed through this thermoplastic resin.
  • Patent Document 3 there is a method for suppressing the shrinkage of the first separator even when the temperature of the battery rises when the cathode electrode is positioned between the two first separators bonded to each other.
  • a second separator is provided between each first separator and the anode electrode.
  • the second separator has a lower melting point than the first separator.
  • Patent Document 3 describes that in this case, the first separator is prevented from shrinking even when the temperature of the battery rises.
  • a cathode electrode or an anode electrode may be positioned between two separators bonded to each other.
  • An object of the present invention is to provide a separator having a high melting point between a cathode electrode and an anode electrode with a novel structure in a battery having a cathode electrode or an anode electrode between two separators bonded to each other.
  • a first electrode having a first surface and having a second surface opposite the first surface; Two first separators, one covering the first surface, the other covering the second surface, the one and the other being bonded together, and the melting point being the first temperature; A second separator located on the opposite side of the first electrode through the one and having a second temperature higher than the first temperature.
  • a first adhesive layer formed by melting a part of the one, and bonding the one and the second separator together;
  • a battery is provided.
  • a high-melting separator in a battery having a cathode electrode or an anode electrode between two separators bonded to each other, a high-melting separator can be provided between the cathode electrode and the anode electrode with a novel structure.
  • FIG. 2 is a cross-sectional view taken along the line AA ′ of FIG.
  • FIG. 3 is an exploded perspective view illustrating a configuration of a unit cell illustrated in FIG. 2.
  • (A) is a plan view showing a configuration of a laminate including the cathode electrode shown in FIG. 3, and (b) is an AA ′ sectional view of (a). It is the figure which expanded the area
  • FIG. 1 is a plan view showing the configuration of the battery according to the first embodiment.
  • FIG. 2 is a cross-sectional view taken along the line AA ′ of FIG.
  • the battery includes a laminate 10, a cathode tab 20, an anode tab 30, a cover member 40, and an electrolytic solution 50.
  • the cover member 40 includes covers 42 and 44 that face each other.
  • the planar shape of the cover member 40 is a rectangle having a long side and a short side.
  • the covers 42 and 44 have a sealing region 46 positioned along each side of the cover member 40.
  • the covers 42 and 44 are bonded to each other in the sealing region 46. Thereby, the area
  • the covers 42 and 44 are formed using, for example, an aluminum film.
  • the laminate 10 and the electrolytic solution 50 are located in a space sealed by the cover member 40.
  • the stacked body 10 includes a plurality of unit cells 100 (details will be described later with reference to FIG. 3) stacked on each other.
  • the electrolytic solution 50 is a nonaqueous electrolytic solution. Specifically, the electrolytic solution 50 contains a lithium salt and an organic solvent.
  • Lithium salt described above for example, LiClO 4, LiBF 6, LiPF 6, LiCF 3 SO 3, LiCF 3 CO 2, LiAsF 6, LiSbF 6, LiB 10 Cl 10, LiAlCl 4, LiCl, LiBr, LiB (C 2 H 5 ) 4 , CF 3 SO 3 Li, CH 3 SO 3 Li, LiC 4 F 9 SO 3 , Li (CF 3 SO 2 ) 2 N, or lithium of a lower fatty acid carboxylate.
  • organic solvent examples include ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate (BC), dimethyl carbonate (DMC), diethyl carbonate (DEC), methyl ethyl carbonate (MEC), and vinylene carbonate (VC).
  • EC ethylene carbonate
  • PC propylene carbonate
  • BC butylene carbonate
  • DMC dimethyl carbonate
  • DEC diethyl carbonate
  • MEC methyl ethyl carbonate
  • VC vinylene carbonate
  • Carbonates such as ⁇ -butyrolactone and ⁇ -valerolactone; ethers such as trimethoxymethane, 1,2-dimethoxyethane, diethyl ether, tetrahydrofuran, and 2-methyltetrahydrofuran; sulfoxides such as dimethyl sulfoxide Oxolanes such as 1,3-dioxolane and 4-methyl-1,3-dioxolane; nitrogen-containing solvents such as acetonitrile, nitromethane, formamide, and dimethylformamide; Organic acid esters such as ethyl acetate, methyl acetate, ethyl acetate, butyl acetate, methyl propionate and ethyl propionate; esters such as phosphate triesters; diglymes; triglymes; sulfolanes such as sulfolane and methylsulfolane; Oxazolidinones such as 3-methyl-2-o
  • the cathode tab 20 and the anode tab 30 protrude outward from the same short side of the cover member 40 in plan view. Further, the cathode tab 20 and the anode tab 30 are located on opposite sides along this side. Thereby, the short circuit of the cathode tab 20 and the anode tab 30 can be prevented.
  • the cathode tab 20 and the anode tab 30 are electrically connected to the unit cell 100 via a cathode lead 200 and an anode lead 300 (described later with reference to FIG. 3), respectively.
  • FIG. 3 is an exploded perspective view showing the configuration of the unit cell 100 shown in FIG.
  • the unit cell 100 includes a cathode electrode 110, an anode electrode 120, a first separator 130, a second separator 140, a cathode lead 200, and an anode lead 300.
  • the cathode lead 200 is electrically connected to the cathode electrode 110.
  • the anode lead 300 is electrically connected to the anode electrode 120.
  • the anode electrode 120, the second separator 140, the first separator 130, the cathode electrode 110, the first separator 130, and the second separator 140 are laminated in this order.
  • the cathode electrode 110 is positioned between the two first separators 130 bonded to each other.
  • a second separator 140 is bonded to the first separator 130 that covers one surface of the cathode electrode 110.
  • a second separator 140 is bonded to the first separator 130 that covers the other surface of the cathode electrode 110.
  • the anode electrode 120, the second separator 140, the first separator 130, the cathode electrode 110, the first separator 130, and the second separator 140 are repeated in this order. Will be stacked.
  • the second separator 140, the first separator 130, the first separator 130, and the second separator 140 are repeatedly laminated in this order. In this case, uneven distribution of the first separator 130 and the second separator 140 can be prevented.
  • both the first separator 130 and the second separator 140 have the same planar shape.
  • the cathode electrode 110 is included inside the first separator 130 and the second separator 140 in plan view.
  • a part of the cathode lead 200 protrudes outside a region overlapping the first separator 130 and the second separator 140.
  • the anode electrode 120 is included inside the first separator 130 and the second separator 140 in plan view.
  • a part of the anode lead 300 protrudes outside a region overlapping with the first separator 130 and the second separator 140.
  • the cathode electrode 110 is included inside the anode electrode 120 in plan view. In this case, even if the arrangement of the cathode electrode 110 is slightly shifted, the area of the region where the cathode electrode 110 and the anode electrode 120 overlap each other is prevented from changing.
  • the cathode electrode 110 contains a cathode active material.
  • the cathode active material is a composite oxide of lithium and a transition metal such as lithium nickel composite oxide, lithium cobalt composite oxide, lithium manganese composite oxide, and lithium-manganese-nickel composite oxide. Transition metal sulfides such as TiS 2 , FeS, and MoS 2 ; transition metal oxides such as MnO, V 2 O 5 , V 6 O 13 , and TiO 2 , or olivine-type lithium phosphate.
  • the anode electrode 120 contains an anode active material.
  • the anode active material is, for example, carbon materials such as artificial graphite, natural graphite, amorphous carbon, diamond-like carbon, fullerene, carbon nanotube, and carbon nanohorn; lithium metal material; alloy such as silicon and tin A system material; an oxide system material such as Nb 2 O 5 and TiO 2 ; or a composite thereof.
  • the cathode lead 200 and the anode lead 300 are formed using a metal (for example, copper or aluminum).
  • FIG. 4A is a plan view showing a configuration of a laminate including the cathode electrode 110 shown in FIG.
  • FIG. 4B is a cross-sectional view taken along the line AA ′ of FIG.
  • FIG. 5 is an enlarged view of a region surrounded by a broken line ⁇ in FIG.
  • the first separator 130 and the second separator 140 that are adjacent to each other are bonded to each other via an adhesive layer 132. Further, the two first separators 130 sandwiching the cathode electrode 110 are also bonded to each other via the adhesive layer 132.
  • the adhesive layer 132 is an adhesive layer formed by melting the first separator 130. Specifically, the melting point of the first separator 130 is the first temperature. On the other hand, the 2nd separator 140 is 2nd temperature whose melting
  • the adhesive layer 132 heats the second separator 140 from the opposite side of the first separator 130 via the second separator 140 to a third temperature that is equal to or higher than the first temperature and lower than the second temperature. It is formed by pressing the second separator 140 against the first separator 130.
  • the cathode electrode 110 is covered with the second separator 140 on both the first surface and the second surface facing each other in the thickness direction. Thereby, the cathode electrode 110 comes to face the anode electrode 120 (FIG. 3) with the second separator 140 interposed therebetween. As described above, the second separator 140 has a high melting point. For this reason, the heat resistance between the cathode electrode 110 and the anode electrode 120 can be made high.
  • 1st temperature is the temperature of 120 to 250 degreeC, for example.
  • 2nd temperature is temperature of 270 degreeC or more and 400 degrees C or less, for example.
  • the 1st separator 130 is formed using the porous resin, for example, is formed using polypropylene or polyethylene.
  • the 2nd separator 140 is formed using porous resin, for example, is formed using polyamide or polyimide.
  • the planar shape of the first separator 130 and the second separator 140 is a rectangle having a long side and a short side.
  • the cathode lead 200 protrudes from one side of the short side of the first separator 130 and the second separator 140.
  • the adhesive layer 132 is disposed on three sides other than the side from which the cathode lead 200 protrudes.
  • a plurality of adhesive layers 132 are arranged in a line along each side in a plan view.
  • FIG. 6 is a diagram showing a first modification of FIG.
  • the contact bonding layer 132 may be arrange
  • the some contact bonding layer 132 is arrange
  • the adhesive layer 132 is not formed in a region overlapping the cathode lead 200 in plan view.
  • FIG. 7 is a diagram showing a second modification of FIG.
  • the contact bonding layer 132 may be arrange
  • the adhesive layer 132 is disposed on the short side facing the short side from which the cathode lead 200 protrudes, and is disposed on one of the remaining two sides. Has been.
  • a plurality of adhesive layers 132 are arranged in a line along each side.
  • FIG. 8 is a diagram showing a third modification of FIG.
  • the contact bonding layer 132 may be continuously formed along each edge
  • the adhesive layers 132 continuously formed along each side are connected to each other. Further, in the example shown in FIG. 5A, one end of the adhesive layer 132 formed along the long side reaches the short side from which the cathode lead 200 protrudes.
  • FIG. 9 is a diagram showing a fourth modification of FIG.
  • the first separator 130 is formed integrally with a first portion that covers one surface of the cathode electrode 110 and a second portion that covers the other surface of the cathode electrode 110.
  • the first separator 130 is folded back from the first part to the second part.
  • the second separator 140 is opposite to the cathode electrode 110 via the first part located on the opposite side of the cathode electrode 110 via the first part of the first separator 130 and the second part of the first separator 130.
  • the part located in the side is formed integrally.
  • the second separator 140 is folded from the first part to the second part.
  • FIG. 10 is a diagram showing an example of a method for manufacturing the laminate shown in FIG.
  • the 2nd separator 140, the 1st separator 130, the cathode electrode 110, the 1st separator 130, and the 2nd separator 140 are laminated
  • the press 600 is pressed against the second separator 140 located in the uppermost layer of the laminate.
  • the tip of the press 600 is heated to a third temperature that is not lower than the first temperature and lower than the second temperature.
  • the second separator 140 in contact with the press 600 does not melt.
  • the heat (third temperature) at the tip of the press 600 is transmitted to the back of the laminate.
  • an adhesive layer 132 (FIG. 4) is formed between the first separator 130 and the second separator 140 that are adjacent to each other and between the two first separators 130 that sandwich the cathode electrode 110.
  • the first temperature is T1 [° C.]
  • the third temperature is, for example, a temperature of (T1 + 5) ° C. or more and (T1 + 50) ° C. or less. More specifically, the third temperature is, for example, a temperature of 125 ° C. or higher and 300 ° C. or lower.
  • any adhesive layer 132 (for example, the adhesive layer 132 between the two first separators 130 sandwiching the cathode electrode 110 and the uppermost layer) positioned in a region overlapping the press 600 in plan view.
  • the adhesive layer 132) between the second separator 140 and the first separator 130 covering one surface of the cathode electrode 110 is also formed almost simultaneously. These adhesive layers 132 overlap each other in plan view.
  • fusing point are bonded together.
  • the first separator 130 and the second separator 140 can be bonded to each other through the adhesive layer 132 formed by melting the first separator 130.
  • One surface of the cathode electrode 110 is covered with the first separator 130 and the second separator 140.
  • the anode electrode 120 located on the opposite side of the cathode electrode 110 via the second separator 140 faces the cathode electrode 110 via the second separator 140. Thereby, the heat resistance between the cathode electrode 110 and the anode electrode 120 can be made high.

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Secondary Cells (AREA)
  • Cell Separators (AREA)
  • Primary Cells (AREA)

Abstract

Un des deux premiers séparateurs (130) recouvre une première surface d'une électrode (110) de cathode, et l'autre recouvre une seconde surface de l'électrode (110) de cathode. En outre, ces deux premiers séparateurs (130) sont liés l'un à l'autre. Les premiers séparateurs (130) ont un point de fusion d'une première température. Les seconds séparateurs (140) sont positionnés sur des côtés opposés de l'électrode (110) de cathode, les premiers séparateurs (130) étant respectivement interposés entre eux. Les seconds séparateurs (140) ont un point de fusion d'une seconde température qui est supérieure à la première température. Des couches de liaison (132) sont formées par la fusion des premiers séparateurs (130). Les premiers séparateurs (130) et les seconds séparateurs (140) sont liés les uns aux autres au moyen des couches de liaison (132).
PCT/JP2015/065413 2014-11-27 2015-05-28 Batterie WO2016084411A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2014240552A JP6511694B6 (ja) 2014-11-27 2014-11-27 電池
JP2014-240552 2014-11-27

Publications (1)

Publication Number Publication Date
WO2016084411A1 true WO2016084411A1 (fr) 2016-06-02

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PCT/JP2015/065413 WO2016084411A1 (fr) 2014-11-27 2015-05-28 Batterie

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WO (1) WO2016084411A1 (fr)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20220166109A1 (en) * 2019-05-22 2022-05-26 Lg Energy Solution, Ltd. Separator laminate for lithium secondary battery, electrode assembly including the same, and lithium secondary battery including the same
KR20200135181A (ko) * 2019-05-22 2020-12-02 주식회사 엘지화학 리튬 이차 전지용 분리막 적층체, 이를 포함하는 전극 조립체 및 리튬 이차 전지

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001035472A (ja) * 1999-07-16 2001-02-09 Shin Kobe Electric Mach Co Ltd 角形非水電解液二次電池
US20070224496A1 (en) * 2006-03-21 2007-09-27 Soonki Woo Separator, a lithium rechargeable battery using the same and a method of manufacture thereof
JP2011210524A (ja) * 2010-03-30 2011-10-20 Sanyo Electric Co Ltd 積層式電池
WO2012060231A1 (fr) * 2010-11-01 2012-05-10 帝人株式会社 Feuilles poreuses liées et procédé de production de celles-ci, séparateur pour batterie secondaire non aqueuse, et batterie secondaire non aqueuse et procédé de production de celle-ci
JP2012151036A (ja) * 2011-01-20 2012-08-09 Hitachi Maxell Energy Ltd ラミネート形電池
JP2014086265A (ja) * 2012-10-24 2014-05-12 Nissan Motor Co Ltd セパレータ接合方法およびセパレータ接合装置

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003059477A (ja) * 2001-08-20 2003-02-28 Sony Corp 電 池
JP2007149507A (ja) * 2005-11-28 2007-06-14 Sanyo Electric Co Ltd 非水電解質二次電池

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001035472A (ja) * 1999-07-16 2001-02-09 Shin Kobe Electric Mach Co Ltd 角形非水電解液二次電池
US20070224496A1 (en) * 2006-03-21 2007-09-27 Soonki Woo Separator, a lithium rechargeable battery using the same and a method of manufacture thereof
JP2011210524A (ja) * 2010-03-30 2011-10-20 Sanyo Electric Co Ltd 積層式電池
WO2012060231A1 (fr) * 2010-11-01 2012-05-10 帝人株式会社 Feuilles poreuses liées et procédé de production de celles-ci, séparateur pour batterie secondaire non aqueuse, et batterie secondaire non aqueuse et procédé de production de celle-ci
JP2012151036A (ja) * 2011-01-20 2012-08-09 Hitachi Maxell Energy Ltd ラミネート形電池
JP2014086265A (ja) * 2012-10-24 2014-05-12 Nissan Motor Co Ltd セパレータ接合方法およびセパレータ接合装置

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JP6511694B6 (ja) 2019-06-12
JP6511694B2 (ja) 2019-05-15
JP2016103377A (ja) 2016-06-02

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