[go: up one dir, main page]

WO2014017091A1 - Secondary battery - Google Patents

Secondary battery Download PDF

Info

Publication number
WO2014017091A1
WO2014017091A1 PCT/JP2013/004515 JP2013004515W WO2014017091A1 WO 2014017091 A1 WO2014017091 A1 WO 2014017091A1 JP 2013004515 W JP2013004515 W JP 2013004515W WO 2014017091 A1 WO2014017091 A1 WO 2014017091A1
Authority
WO
WIPO (PCT)
Prior art keywords
plate
battery case
secondary battery
gasket
sealing body
Prior art date
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.)
Ceased
Application number
PCT/JP2013/004515
Other languages
French (fr)
Japanese (ja)
Inventor
佑治 大竹
啓介 清水
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Panasonic Corp
Original Assignee
Panasonic Corp
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 Panasonic Corp filed Critical Panasonic Corp
Publication of WO2014017091A1 publication Critical patent/WO2014017091A1/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/04—Construction or manufacture in general
    • H01M10/0431—Cells with wound or folded electrodes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/10—Primary casings; Jackets or wrappings
    • H01M50/147—Lids or covers
    • H01M50/166—Lids or covers characterised by the methods of assembling casings with lids
    • H01M50/167—Lids or covers characterised by the methods of assembling casings with lids by crimping
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/10—Primary casings; Jackets or wrappings
    • H01M50/102—Primary casings; Jackets or wrappings characterised by their shape or physical structure
    • H01M50/107—Primary casings; Jackets or wrappings characterised by their shape or physical structure having curved cross-section, e.g. round or elliptic
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/10—Primary casings; Jackets or wrappings
    • H01M50/147—Lids or covers
    • H01M50/166—Lids or covers characterised by the methods of assembling casings with lids
    • H01M50/171—Lids or covers characterised by the methods of assembling casings with lids using adhesives or sealing agents
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/10—Primary casings; Jackets or wrappings
    • H01M50/183—Sealing members
    • H01M50/186—Sealing members characterised by the disposition of the sealing members
    • H01M50/188—Sealing members characterised by the disposition of the sealing members the sealing members being arranged between the lid and terminal
    • Y—GENERAL 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
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Definitions

  • the present invention relates to a secondary battery in which an opening of a battery case is sealed by a sealing body via a gasket.
  • a conventional secondary battery (hereinafter sometimes simply referred to as “battery”) has the following configuration.
  • a concave portion that is recessed toward the inside of the battery case is formed on a side surface portion of the battery case.
  • the sealing body is arrange
  • the open end of the battery case is caulked to the peripheral edge of the sealing body via a gasket.
  • the opening of the battery case is sealed by the sealing body via a gasket between the battery case and the sealing body.
  • the gasket and the battery case are electrically insulated by the gasket.
  • a sealing agent may be applied to the inner surface of the recess of the battery case.
  • an organic solvent is used as the electrolytic solution, if the electrolytic solution adheres to the sealing agent when the electrolytic solution is injected, the sealing property may be dissolved, resulting in a decrease in airtightness.
  • the gasket interposed between the sealing body and the battery case is composed of at least two layers of a base resin layer and a surface resin layer in contact with the battery case.
  • FIG. 9 is a cross-sectional view showing a configuration of a part of the battery, specifically, a cross-sectional view showing a configuration of the open end portion of the battery case caulked to the peripheral portion of the sealing body via a gasket.
  • the open end of the battery case 105 is caulked to the peripheral edge of the sealing body 110 via a gasket 117.
  • an object of the present invention is to provide a secondary battery in which an opening of a battery case is sealed by a sealing body via a gasket, and even if the gasket may melt, the sealing body and the battery case are short-circuited. It is to prevent that.
  • a secondary battery according to the present invention is a secondary battery having an electrode group in which a positive electrode plate and a negative electrode plate are wound through a separator therebetween, and a cylindrical battery case that houses the electrode group;
  • a sealing body that seals the opening of the battery case via a first gasket between the battery case, and the opening end of the battery case is located at the periphery of the sealing body via the first gasket.
  • a ring-shaped insulating plate is disposed between the peripheral edge portion of the sealing body and the caulked portion of the battery case.
  • FIG. 1 is a cross-sectional view showing a configuration of a secondary battery according to the first embodiment of the present invention.
  • FIG. 2 is a perspective view showing the configuration of the insulating plate.
  • FIG. 3 is a cross-sectional view showing the configuration of the secondary battery according to the first modification of the first embodiment of the present invention.
  • FIG. 4 is a perspective view showing the configuration of the insulating plate.
  • FIG. 5 is a cross-sectional view showing the configuration of the secondary battery according to the second modification of the first embodiment of the present invention.
  • FIG. 6 is a perspective view showing the configuration of the insulating plate.
  • FIG. 7 is a cross-sectional view showing a configuration of a secondary battery according to the second embodiment of the present invention.
  • FIG. 8 is a cross-sectional view showing a configuration of a secondary battery according to another example of the first embodiment of the present invention.
  • FIG. 9 is a cross-sectional view showing a configuration of a part of the battery.
  • the present inventors have found that the upper surface of the peripheral portion of the sealing body 110 and the crimped portion of the battery case 105 are most likely to come into contact with each other. I found it. In other words, the probability that the upper surface of the peripheral portion of the sealing body 110 and the caulking portion of the battery case 105 are in contact with each other due to melting of the gasket 117 is greater than the probability that the side surface of the sealing body 110 and the battery case 105 are in contact with each other due to melting of the gasket 117.
  • the present inventors have found that the cost is high.
  • the caulking portion of the battery case 105 is C-shaped as shown in FIG. 9, the distance between the end of the caulking portion of the battery case 105 and the upper surface of the peripheral portion of the sealing body 110 is the shortest. For this reason, the end of the caulking portion of the battery case 105 is most easily in contact with the upper surface of the peripheral portion of the sealing body 110.
  • Contact between the end of the caulking portion of the battery case 105 and the upper surface of the peripheral portion of the sealing body 110 is line contact.
  • the contact between the side surface of the sealing body 110 and the battery case 105 is a surface contact. Line contact is more likely to occur than surface contact. Therefore, the upper surface of the peripheral part of the sealing body 110 and the caulking part of the battery case 105 are most easily in contact with each other.
  • FIG. 1 is a cross-sectional view showing the configuration of the secondary battery according to the present embodiment.
  • FIG. 2 is a perspective view showing the configuration of the insulating plate.
  • a case where a lithium ion secondary battery is used as the secondary battery will be described as a specific example.
  • an electrode group 4 in which a positive electrode plate 1 and a negative electrode plate 2 are wound through a separator 3 between them is housed in a cylindrical battery case 5 together with an electrolytic solution.
  • the positive electrode plate 1 includes a positive electrode current collector and a positive electrode mixture layer that is formed on the positive electrode current collector and includes a positive electrode active material.
  • the negative electrode plate 2 has a negative electrode current collector and a negative electrode mixture layer formed on the negative electrode current collector and containing a negative electrode active material.
  • the positive electrode plate 1 is connected to a sealing body 10 (specifically, a metal plate 11 constituting the sealing body 10) via a positive electrode lead 6.
  • the negative electrode plate 2 is connected to the bottom of the battery case 5 via the negative electrode lead 7.
  • An insulating plate 8 is disposed on the upper end of the electrode group 4 (the end on the opening side of the battery case 5 in the electrode group 4).
  • an insulating plate 9 is disposed on the lower end of the electrode group 4 (the end of the electrode group 4 on the bottom side of the battery case 5).
  • a dent that is recessed toward the inside of the battery case 5 is formed on the side surface of the battery case 5.
  • the sealing body 10 is disposed on the recessed portion via a gasket (first gasket) 17.
  • the opening end of the battery case 5 is caulked to the peripheral edge of the sealing body 10 via the gasket 17.
  • the opening of the battery case 5 is sealed by the sealing body 10 via the gasket 17 between the battery case 5 and the sealing body 10.
  • a sealant may be applied to the inner surface of the recess.
  • the battery case 5 has a recessed portion and a caulking portion (that is, an opening end portion) that is caulked to the peripheral edge portion of the sealing body 10 via the gasket 17.
  • the cross-sectional shape of the caulking portion of the battery case 5 is C-shaped as shown in FIG.
  • the “caulking part of the battery case 5” refers to a bent part when the battery case 5 is caulked.
  • the battery case before forming the recess has a bottomed cylindrical shape.
  • the sealing body 10 includes a metal plate 11, a valve plate (first valve plate) 12 disposed on the metal plate 11, and a valve plate (second valve plate) disposed on the valve plate 12. ) 14, an annular PTC (Positive TemperatureefficientCoefficient) element 15 disposed on the valve plate 14, a cap 16 disposed on the PTC element 15 and also serving as a positive electrode terminal, and a peripheral portion of the valve plate 12 And a gasket (second gasket) 13 interposed between the peripheral portion of the valve plate 14.
  • the “PTC element” is an element having a positive temperature coefficient, and an internal resistance increases as the temperature rises.
  • the peripheral edge of the metal plate 11 is caulked to the peripheral edge of the cap 16 via the gasket 13.
  • the metal plate 11, the valve plate 12, the gasket 13, the valve plate 14, the PTC element 15, and the cap 16 are integrally formed.
  • the cap 14 has a portion that contacts the PTC element 15 and a protruding portion that protrudes upward.
  • “upper side” refers to a direction toward the opening side of the battery case 5 among directions in which the winding axis of the electrode group 4 extends.
  • the metal plate 11 has a peripheral portion (that is, a caulking portion that is caulked to the peripheral portion of the cap 16 via the gasket 13), a portion that contacts the valve plate 12, and a protruding portion that protrudes downward.
  • “lower side” refers to a direction toward the bottom side of the battery case 5 in a direction in which the winding axis of the electrode group 4 extends.
  • the cross-sectional shape of the caulking portion (that is, the peripheral portion) of the metal plate 11 is L-shaped as shown in FIG.
  • the “caulking portion of the metal plate 11” refers to a portion bent when the metal plate 11 is caulked.
  • the peripheral part of the metal plate before caulking is plate-shaped.
  • valve plate 12 and the central part of the valve plate 14 are in contact with each other.
  • the valve plates 12 and 14 have thin portions with a small thickness.
  • the cap 16 has an opening communicating with the outside of the battery. An opening is formed in the metal plate 11. An opening is formed in the insulating plate 8.
  • the gas generated in the battery is exhausted out of the battery as follows.
  • the pressure in the battery rises and exceeds a predetermined pressure
  • the thin portions of the valve plates 12 and 14 break.
  • the gas generated in the battery passes through the opening of the insulating plate 8, the opening of the metal plate 11, the rupture of the valve plate 12, the rupture of the valve plate 14 and the opening of the cap 16. Exhausted.
  • an insulating plate 18 is interposed between the peripheral portion of the sealing body 10 (specifically, the caulking portion of the metal plate 11 constituting the sealing body 10) and the caulking portion of the battery case 5. It is arranged. As shown in FIG. 2, the insulating plate 18 has a ring shape.
  • the insulating plate 18 is in contact with the upper surface of the caulking portion of the metal plate 11.
  • the opening end portion (that is, the caulking portion) of the battery case 5 is connected to the peripheral portion of the sealing body 10 (specifically, the metal constituting the sealing body 10) via the gasket 17 and the insulating plate 18 in order from the battery case 5 side. It is caulked to the caulking portion of the plate 11.
  • the inner end surface of the ring-shaped insulating plate 18 is located on the inner side (in other words, the winding axis side of the electrode group 4) than the end surface of the caulking portion of the battery case 5. preferable.
  • the insulating plate 18 is preferably made of a high melting point material having a higher melting point than the material of the gasket 17.
  • the gasket 17 is made of PP (polypropylene)
  • the insulating plate 18 is made of, for example, PFA (polytetrafluoroethylene-co-perfluoropropylvinylether), PTFE (polytetrafluoroethylene).
  • PFA polytetrafluoroethylene-co-perfluoropropylvinylether
  • PTFE polytetrafluoroethylene
  • PPS polyphenylene sulfide
  • PBT polybutylene terephthalate
  • Pl polyimide
  • the insulating plate 18 is more preferably made of a high melting point material having a mechanical strength (tensile strength) lower than that of the gasket 17.
  • the insulating plate 18 is more preferably made of, for example, PFA or PTFE.
  • the caulking portion of the metal plate 11 between the peripheral portion of the sealing body 10 (specifically, the caulking portion of the metal plate 11 constituting the sealing body 10) and the caulking portion of the battery case 5.
  • An insulating plate 18 that abuts on the upper surface is disposed, and the insulating plate 18 is made of a high melting point material having a higher melting point than the material of the gasket 17. For this reason, even if the gasket 17 is melted when the battery is exposed to a high temperature environment, the insulating plate 18 is not melted. Therefore, the upper surface of the caulking portion of the metal plate 11 and the caulking portion of the battery case 5 are not melted. Can be prevented from coming into contact with each other. Therefore, it is possible to prevent the sealing body 10 (specifically, the metal plate 11 constituting the sealing body 10) and the battery case 5 from being short-circuited.
  • the insulating plate 18 is made of a high melting point material having lower strength than the material of the gasket 17.
  • FIG. 3 is a cross-sectional view showing the configuration of the secondary battery according to this modification.
  • FIG. 4 is a perspective view showing the configuration of the insulating plate.
  • the same components as those in the first embodiment are denoted by the same reference numerals as those in FIG. Therefore, in this modification, the description similar to that of the first embodiment is omitted as appropriate.
  • the ring-shaped insulating plate 18 is in contact with the upper surface of the caulking portion of the metal plate 11.
  • the ring-shaped insulating plate 18 ⁇ / b> X is in contact with the upper surface and the side surface of the caulking portion of the metal plate 11.
  • the insulating plate 18X has a flat portion and a protruding portion that protrudes downward from the outer end portion of the flat portion.
  • the flat portion is in contact with the upper surface of the caulking portion of the metal plate 11.
  • the protruding portion is in contact with the side surface of the caulking portion of the metal plate 11.
  • the cross-sectional shape of the insulating plate 18X is L-shaped.
  • the probability that the upper surface of the peripheral portion of the sealing body and the caulking portion of the battery case are in contact with each other due to melting of the gasket is higher than the probability that the side surface of the sealing body and the battery case are in contact with each other due to melting of the gasket. Therefore, in the first embodiment, as shown in FIG. 1, the insulating plate 18 is disposed in a region where the contact probability is relatively high. Specifically, the metal plate 11 is caulked between the upper surface of the peripheral portion of the sealing body 10 (specifically, the caulking portion of the metal plate 11 constituting the sealing body 10) and the caulking portion of the battery case 5. An insulating plate 18 that contacts the upper surface of the part is disposed.
  • the insulating plate 18X is disposed not only in the region where the contact probability is relatively high but also in the region where the contact probability is relatively low. Specifically, not only between the upper surface of the caulking portion of the metal plate 11 and the caulking portion of the battery case 5, but also between the side surface of the caulking portion of the metal plate 11 and the caulking portion of the battery case 5. An insulating plate 18X that contacts the upper and side surfaces of the caulking portion of the plate 11 is disposed.
  • the same effect as that of the first embodiment can be obtained. Specifically, even if the gasket 17 is melted, the insulating plate 18X having a melting point higher than that of the gasket 17 is not melted. Therefore, the upper surface of the caulking portion of the metal plate 11 and the caulking portion of the battery case 5 are not melted. Can be prevented from coming into contact with each other. Therefore, it is possible to prevent the sealing body 10 (specifically, the metal plate 11 constituting the sealing body 10) and the battery case 5 from being short-circuited. Further, the insulating plate 18X is made of a high melting point material having lower strength than the material of the gasket 17, thereby preventing the gasket 17 from cracking and the gasket 17 from cracking when the battery case 5 is caulked. be able to.
  • the insulating plate 18X has a protruding portion that contacts the side surface of the caulking portion of the metal plate 11. Thereby, it can prevent that the side surface of the crimping part of the metal plate 11 and the crimping part of the battery case 5 contact. Therefore, it is possible to further prevent the sealing body 10 (specifically, the metal plate 11 constituting the sealing body 10) and the battery case 5 from being short-circuited.
  • FIG. 5 is a cross-sectional view showing the configuration of the secondary battery according to this modification.
  • FIG. 6 is a perspective view showing the configuration of the insulating plate.
  • the same components as those in the first embodiment are denoted by the same reference numerals as those in FIG. Therefore, in this modification, the description similar to that of the first embodiment is omitted as appropriate.
  • the ring-shaped insulating plate 18 is in contact with the upper surface of the caulking portion of the metal plate 11.
  • the ring-shaped insulating plate 18Y has a flat portion and a protruding portion protruding upward from the inner end portion of the flat portion.
  • the flat portion is in contact with the upper surface of the caulking portion of the metal plate 11.
  • the protruding portion is in contact with the side surface of the protruding portion of the cap 14.
  • the cross-sectional shape of the insulating plate 18Y is L-shaped.
  • the same effect as that of the first embodiment can be obtained. Specifically, even if the gasket 17 is melted, the insulating plate 18Y having a melting point higher than that of the gasket 17 is not melted. Therefore, the upper surface of the caulking portion of the metal plate 11 and the caulking portion of the battery case 5 are not melted. Can be prevented from coming into contact with each other. Therefore, it is possible to prevent the sealing body 10 (specifically, the metal plate 11 constituting the sealing body 10) and the battery case 5 from being short-circuited.
  • the insulating plate 18Y is made of a high melting point material having lower strength than the material of the gasket 17, it is possible to prevent the gasket 17 from cracking and the gasket 17 from cracking when the battery case 5 is caulked. be able to.
  • the insulating plate 18Y has a protruding portion that contacts the side surface of the protruding portion of the cap 16.
  • FIG. 7 is a cross-sectional view showing the configuration of the secondary battery according to the present embodiment.
  • the same components as those in the first embodiment are denoted by the same reference numerals as those in FIG. Therefore, in this embodiment, the same description as that of the first embodiment is omitted as appropriate.
  • the peripheral portion of the sealing body 10 (specifically, the caulking portion of the metal plate 11 constituting the sealing body 10) and the caulking portion of the battery case 5.
  • the disposed insulating plate 18 is in contact with the caulking portion of the metal plate 11.
  • the opening end portion (that is, the caulking portion) of the battery case 5 is caulked to the peripheral edge portion of the sealing body 10 via the gasket 17 and the insulating plate 18 in order from the battery case 5 side.
  • the insulating plate 18 ⁇ / b> Z disposed between the caulking portion of the metal plate 11 and the caulking portion of the battery case 5 is used as the caulking portion of the battery case 5. Abut. The opening end portion of the battery case 5 is caulked to the peripheral edge portion of the sealing body 10 via the insulating plate 18Z and the gasket 17 in order from the battery case 5 side.
  • the insulating plate 18 ⁇ / b> Z has a shape along the caulking portion of the battery case 5.
  • the inner end surface of the ring-shaped insulating plate 18 ⁇ / b> Z is located on the inner side (in other words, the winding axis side of the electrode group 4) than the end surface of the caulking portion of the battery case 5. preferable.
  • the same effect as that of the first embodiment can be obtained. Specifically, even if the gasket 17 is melted, the insulating plate 18Z having a melting point higher than that of the gasket 17 is not melted. Therefore, the upper surface of the caulking portion of the metal plate 11 and the caulking portion of the battery case 5 are not melted. Can be prevented from coming into contact with each other. Therefore, it is possible to prevent the sealing body 10 (specifically, the metal plate 11 constituting the sealing body 10) and the battery case 5 from being short-circuited. Furthermore, the insulating plate 18Z is made of a high melting point material having lower strength than the material of the gasket 17, thereby preventing the gasket 17 from cracking and the gasket 17 from cracking when the battery case 5 is caulked. be able to.
  • the sealing body 10 includes a metal plate 11, It has a valve plate 12, a gasket 13, a valve plate 14, a PTC element 15, and a cap 16, and the peripheral portion of the metal plate 11 is caulked to the peripheral portion of the cap 16 via the gasket 13.
  • the present invention is not limited thereto.
  • the sealing body 20 includes a metal plate 21, a valve plate 22, a gasket 23, a valve plate 24, a PTC element 25, and a cap 26.
  • the portion may not be caulked to the peripheral edge portion of the cap 16 via the gasket 23.
  • the upper surface of the peripheral portion of the cap 26 is brought into contact between the peripheral portion of the sealing body 20 (specifically, the peripheral portion of the cap 26 constituting the sealing body 20) and the caulking portion of the battery case 5.
  • a ring-shaped insulating plate 28 is provided.
  • the cap 26 and the caulking portion of the battery case 5 are in contact with the upper surface of the peripheral portion of the cap 26 and have the same shape as the insulating plate 18 of the first embodiment.
  • the insulating plate 28 is disposed has been described as a specific example, the present invention is not limited to this.
  • An insulating plate having a projecting portion that comes into contact with the side surface (the end surface of the cap) may be disposed.
  • An insulating plate having a protruding portion that abuts on the side surface of the plate may be disposed.
  • an insulating plate that is in contact with the caulking portion of the battery case and has the same shape as the insulating plate 18Z of the second embodiment is disposed between the peripheral portion of the cap and the caulking portion of the battery case. It may be provided.
  • the sealing body 10 includes a metal plate 11, It has a valve plate 12, a gasket 13, a valve plate 14, a PTC element 15, and a cap 16, and the peripheral portion of the metal plate 11 is caulked to the peripheral portion of the cap 16 via the gasket 13.
  • the sealing body has at least a metal plate and a cap disposed above the metal plate, and the peripheral portion of the metal plate may be caulked to the peripheral portion of the cap.
  • the reason why the sealing body 10 includes the valve plate 12, the gasket 13, and the valve plate 14 is as follows. Depending on the reason. It is preferable to have a function of cutting off the current flowing between the metal plate 11 and the cap 16 when gas is generated in the battery and the pressure in the battery rises and exceeds a predetermined pressure. Therefore, the sealing body 10 has a thin wall portion that can be broken when the pressure in the battery exceeds a predetermined pressure, and the central portions of the valve plates 12 and 14 are in contact with each other.
  • the gasket 13 is interposed between the peripheral edge and the peripheral edge of the valve plate 14.
  • valve plate 12 and the valve plate 14 are separated from each other. Therefore, the metal plate 11 and the cap 16 that are electrically connected via the valve plates 12 and 14 It is possible to cut off the current flowing between.
  • the reason why the sealing body 10 has the PTC element 15 is as follows. It is preferable that the battery has a function of interrupting current flowing between the metal plate 11 and the cap 16 when the temperature in the battery rises and exceeds a predetermined temperature. Therefore, the sealing body 10 is interposed between the valve plate 14 electrically connected to the metal plate 11 and the cap 16, and the internal resistance can be increased when the temperature in the battery exceeds a predetermined temperature. PTC element 15 is included. As a result, when the internal resistance of the PTC element 15 increases, the current flowing between the valve plate 14 and the cap 16 is cut off, so that the gap between the metal plate 11 and the cap 16 electrically connected to the valve plate 14 is reduced. It is possible to cut off the current flowing through the.
  • the sealing body does not necessarily need to have the two valve plates 12 and 14 and the gasket 13.
  • the sealing body may have a metal plate, a PTC element disposed on the metal plate, and a cap disposed on the PTC element.
  • the sealing body does not necessarily need to have the PTC element 15.
  • the sealing body includes a metal plate, a first valve plate disposed on the metal plate, a second valve plate disposed on the first valve plate, and a second valve plate. You may have the cap arrange
  • the present invention can prevent the sealing body and the battery case from being short-circuited even if the gasket is melted, and the secondary battery in which the opening of the battery case is sealed by the sealing body via the gasket Useful for.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Sealing Battery Cases Or Jackets (AREA)

Abstract

This secondary battery is provided with: a cylindrical battery case (5) for containing an electrode group (4); and a sealing body (10) for sealing the opening of the battery case (5) by the intermediary of a first gasket (17) that is interposed between the battery case (5) and the sealing body (10). The end portion of the opening of the battery case (5) is caulked onto the peripheral portion of the sealing body (10) with the first gasket (17) interposed therebetween. A ring-like insulating plate (18) is arranged between the peripheral portion of the sealing body (10) and the caulked portion of the battery case (5).

Description

二次電池Secondary battery

　本発明は、電池ケースの開口部がガスケットを介して封口体により封口された二次電池に関する。 The present invention relates to a secondary battery in which an opening of a battery case is sealed by a sealing body via a gasket.

　従来の二次電池（以下、単に「電池」ということもある）は、次のような構成を有している。正極板及び負極板をそれらの間にセパレータを介して捲回した電極群が、電解液と共に、電池ケース内に収容されている。電池ケースの側面部には、電池ケースの内側に向かって凹む凹み部が形成されている。封口体は、ガスケットを介して、凹み部の上に配設されている。電池ケースの開口端部は、ガスケットを介して、封口体の周縁部にかしめられている。電池ケースの開口部は、電池ケースと封口体との間にガスケットを介して、封口体により封口されている。ガスケットにより、封口体と電池ケースとの間が電気的に絶縁されている。 A conventional secondary battery (hereinafter sometimes simply referred to as “battery”) has the following configuration. An electrode group in which a positive electrode plate and a negative electrode plate are wound with a separator interposed between them is housed in a battery case together with an electrolytic solution. A concave portion that is recessed toward the inside of the battery case is formed on a side surface portion of the battery case. The sealing body is arrange | positioned on the recessed part through the gasket. The open end of the battery case is caulked to the peripheral edge of the sealing body via a gasket. The opening of the battery case is sealed by the sealing body via a gasket between the battery case and the sealing body. The gasket and the battery case are electrically insulated by the gasket.

　充分な気密性の維持を考慮して、電池ケースの凹み部の内側面には、封止剤が塗布されていることがある。しかしながら、電解液として、有機溶媒を用いた場合、電解液の注液時に、電解液が封止剤に付着すると、封止剤の溶解により、気密性の低下を招く虞がある。 In consideration of maintaining sufficient airtightness, a sealing agent may be applied to the inner surface of the recess of the battery case. However, when an organic solvent is used as the electrolytic solution, if the electrolytic solution adheres to the sealing agent when the electrolytic solution is injected, the sealing property may be dissolved, resulting in a decrease in airtightness.

　そこで、特許文献１に記載の技術では、封口体と電池ケースとの間に介在するガスケットが、基材樹脂層と、電池ケースと接触する表面樹脂層との少なくとも２層からなる。これにより、凹み部の内側面に、封止剤を塗布しなくても、気密性を充分に維持することができる。従って、注液時に、電解液が封止剤に付着することはないため、封止剤の溶解による気密性の低下を防止することができる。 Therefore, in the technique described in Patent Document 1, the gasket interposed between the sealing body and the battery case is composed of at least two layers of a base resin layer and a surface resin layer in contact with the battery case. Thereby, even if it does not apply | coat a sealing agent to the inner surface of a dent part, airtightness can fully be maintained. Therefore, the electrolyte solution does not adhere to the sealant at the time of pouring, so that a decrease in airtightness due to the dissolution of the sealant can be prevented.

特開２００８－２０４８３９号公報JP 2008-204839 A

　ところで、本願発明者らは、鋭意検討を重ねた結果、電池ケースの開口部がガスケットを介して封口体により封口された二次電池の場合、以下の問題があることを見出した。この問題について、図９を参照しながら説明する。図９は、電池の一部分の構成を示す断面図であり、具体的には、ガスケットを介して封口体の周縁部にかしめられた電池ケースの開口端部の構成を示す断面図である。 By the way, as a result of intensive studies, the inventors of the present application have found that the secondary battery in which the opening of the battery case is sealed by a sealing body via a gasket has the following problems. This problem will be described with reference to FIG. FIG. 9 is a cross-sectional view showing a configuration of a part of the battery, specifically, a cross-sectional view showing a configuration of the open end portion of the battery case caulked to the peripheral portion of the sealing body via a gasket.

　図９に示すように、電池ケース１０５の開口端部は、ガスケット１１７を介して、封口体１１０の周縁部にかしめられている。 As shown in FIG. 9, the open end of the battery case 105 is caulked to the peripheral edge of the sealing body 110 via a gasket 117.

　図９に示す電池が高温環境下に晒されることにより、ガスケット１１７が溶融すると、封口体１１０と電池ケース１０５とが接触し、封口体１１０と電池ケース１０５とが短絡するという問題がある。 If the battery shown in FIG. 9 is exposed to a high temperature environment and the gasket 117 is melted, the sealing body 110 and the battery case 105 come into contact with each other, and the sealing body 110 and the battery case 105 are short-circuited.

　前記に鑑み、本発明の目的は、電池ケースの開口部がガスケットを介して封口体により封口された二次電池において、ガスケットが溶融することがあっても、封口体と電池ケースとが短絡することを防止することにある。 In view of the above, an object of the present invention is to provide a secondary battery in which an opening of a battery case is sealed by a sealing body via a gasket, and even if the gasket may melt, the sealing body and the battery case are short-circuited. It is to prevent that.

　本発明に係る二次電池は、正極板及び負極板がそれらの間にセパレータを介して捲回された電極群を有する二次電池であって、電極群を収容する円筒形の電池ケースと、電池ケースとの間に第１のガスケットを介して、電池ケースの開口部を封口する封口体とを備え、電池ケースの開口端部は、第１のガスケットを介して、封口体の周縁部にかしめられており、封口体の周縁部と電池ケースのかしめ部との間には、リング状の絶縁板が配設されている。 A secondary battery according to the present invention is a secondary battery having an electrode group in which a positive electrode plate and a negative electrode plate are wound through a separator therebetween, and a cylindrical battery case that houses the electrode group; A sealing body that seals the opening of the battery case via a first gasket between the battery case, and the opening end of the battery case is located at the periphery of the sealing body via the first gasket. A ring-shaped insulating plate is disposed between the peripheral edge portion of the sealing body and the caulked portion of the battery case.

　本発明によれば、ガスケットが溶融することがあっても、封口体と電池ケースとが短絡することを防止することができる。 According to the present invention, even when the gasket is melted, it is possible to prevent the sealing body and the battery case from being short-circuited.

図１は、本発明の第１の実施形態に係る二次電池の構成を示す断面図である。FIG. 1 is a cross-sectional view showing a configuration of a secondary battery according to the first embodiment of the present invention. 図２は、絶縁板の構成を示す斜視図である。FIG. 2 is a perspective view showing the configuration of the insulating plate. 図３は、本発明の第１の実施形態の第１の変形例に係る二次電池の構成を示す断面図である。FIG. 3 is a cross-sectional view showing the configuration of the secondary battery according to the first modification of the first embodiment of the present invention. 図４は、絶縁板の構成を示す斜視図である。FIG. 4 is a perspective view showing the configuration of the insulating plate. 図５は、本発明の第１の実施形態の第２の変形例に係る二次電池の構成を示す断面図である。FIG. 5 is a cross-sectional view showing the configuration of the secondary battery according to the second modification of the first embodiment of the present invention. 図６は、絶縁板の構成を示す斜視図である。FIG. 6 is a perspective view showing the configuration of the insulating plate. 図７は、本発明の第２の実施形態に係る二次電池の構成を示す断面図である。FIG. 7 is a cross-sectional view showing a configuration of a secondary battery according to the second embodiment of the present invention. 図８は、本発明の第１の実施形態のその他の例に係る二次電池の構成を示す断面図である。FIG. 8 is a cross-sectional view showing a configuration of a secondary battery according to another example of the first embodiment of the present invention. 図９は、電池の一部分の構成を示す断面図である。FIG. 9 is a cross-sectional view showing a configuration of a part of the battery.

　本願発明者らは、本願発明者らが見出した問題について、さらに鋭意検討を重ねた結果、以下の知見を見出した。 The inventors of the present application have found the following findings as a result of further intensive studies on the problems found by the inventors of the present application.

　図９に示す電池が高温環境下に晒されることにより、ガスケット１１７が溶融すると、封口体１１０の周縁部の上面と電池ケース１０５のかしめ部とが最も接触し易いことを、本願発明者らは見出した。言い換えれば、ガスケット１１７の溶融により封口体１１０の周縁部の上面と電池ケース１０５のかしめ部とが接触する確率は、ガスケット１１７の溶融により封口体１１０の側面と電池ケース１０５とが接触する確率よりも、高いことを、本願発明者らは見出した。 When the battery shown in FIG. 9 is exposed to a high temperature environment and the gasket 117 is melted, the present inventors have found that the upper surface of the peripheral portion of the sealing body 110 and the crimped portion of the battery case 105 are most likely to come into contact with each other. I found it. In other words, the probability that the upper surface of the peripheral portion of the sealing body 110 and the caulking portion of the battery case 105 are in contact with each other due to melting of the gasket 117 is greater than the probability that the side surface of the sealing body 110 and the battery case 105 are in contact with each other due to melting of the gasket 117. However, the present inventors have found that the cost is high.

　封口体１１０の周縁部の上面と電池ケース１０５のかしめ部とが最も接触し易い理由は、以下のように推測される。 The reason why the upper surface of the peripheral edge portion of the sealing body 110 and the caulking portion of the battery case 105 are most likely to contact each other is estimated as follows.

　第１に、高温環境下に晒された電池内には、ガスが発生している。このため、ガス圧により、封口体１１０が、上側の方向（即ち、電池ケース１０５の開口部側に向かう方向）に持ち上げられるため、封口体１１０の周縁部の上面と電池ケース１０５のかしめ部とが最も接触し易い。 First, gas is generated in the battery exposed to a high temperature environment. For this reason, since the sealing body 110 is lifted by the gas pressure in the upper direction (that is, the direction toward the opening side of the battery case 105), the upper surface of the peripheral portion of the sealing body 110 and the caulking portion of the battery case 105 Is the easiest to touch.

　第２に、電池ケース１０５のかしめ部は、図９に示すように、Ｃ字状であるため、電池ケース１０５のかしめ部における端と封口体１１０の周縁部の上面との距離が最も近い。このため、電池ケース１０５のかしめ部における端が、封口体１１０の周縁部の上面と最も接触し易い。電池ケース１０５のかしめ部における端と封口体１１０の周縁部の上面との接触は、線接触である。これに対し、封口体１１０の側面と電池ケース１０５との接触は、面接触である。線接触は、面接触よりも、起こり易い。よって、封口体１１０の周縁部の上面と電池ケース１０５のかしめ部とが最も接触し易い。 Second, since the caulking portion of the battery case 105 is C-shaped as shown in FIG. 9, the distance between the end of the caulking portion of the battery case 105 and the upper surface of the peripheral portion of the sealing body 110 is the shortest. For this reason, the end of the caulking portion of the battery case 105 is most easily in contact with the upper surface of the peripheral portion of the sealing body 110. Contact between the end of the caulking portion of the battery case 105 and the upper surface of the peripheral portion of the sealing body 110 is line contact. On the other hand, the contact between the side surface of the sealing body 110 and the battery case 105 is a surface contact. Line contact is more likely to occur than surface contact. Therefore, the upper surface of the peripheral part of the sealing body 110 and the caulking part of the battery case 105 are most easily in contact with each other.

　以下に、本発明の実施形態について、図面を参照しながら説明する。なお、以下の実施形態は、本発明の単なる例示形態に過ぎず、本発明は、これらに限定されるものではない。本発明は、本発明の要旨を逸脱しない範囲内で、種々の変形又は変更が可能であり、該変形例及び該変更例も本発明の範囲内に含まれる。図面において、各構成要素は、図示に適した寸法比率で図示されており、図示した寸法比率は、実際の寸法比率とは異なる場合がある。 Hereinafter, embodiments of the present invention will be described with reference to the drawings. The following embodiments are merely exemplary forms of the present invention, and the present invention is not limited to these. The present invention can be variously modified or changed without departing from the gist of the present invention, and such modified examples and modified examples are also included in the scope of the present invention. In the drawings, each component is illustrated in a dimensional ratio suitable for illustration, and the illustrated dimensional ratio may be different from the actual dimensional ratio.

　（第１の実施形態）
　以下に、本発明の第１の実施形態に係る二次電池について、図１及び図２を参照しながら説明する。図１は、本実施形態に係る二次電池の構成を示す断面図である。図２は、絶縁板の構成を示す斜視図である。本実施形態では、二次電池として、リチウムイオン二次電池を用いた場合を具体例に挙げて説明する。 (First embodiment)
The secondary battery according to the first embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a cross-sectional view showing the configuration of the secondary battery according to the present embodiment. FIG. 2 is a perspective view showing the configuration of the insulating plate. In the present embodiment, a case where a lithium ion secondary battery is used as the secondary battery will be described as a specific example.

　図１に示すように、正極板１及び負極板２がそれらの間にセパレータ３を介して捲回された電極群４が、電解液と共に、円筒形の電池ケース５内に収容されている。図１において詳細な図示を省略したが、正極板１は、正極集電体と、正極集電体の上に形成され且つ正極活物質を含む正極合剤層とを有している。負極板２は、負極集電体と、負極集電体の上に形成され且つ負極活物質を含む負極合剤層とを有している。 As shown in FIG. 1, an electrode group 4 in which a positive electrode plate 1 and a negative electrode plate 2 are wound through a separator 3 between them is housed in a cylindrical battery case 5 together with an electrolytic solution. Although not shown in detail in FIG. 1, the positive electrode plate 1 includes a positive electrode current collector and a positive electrode mixture layer that is formed on the positive electrode current collector and includes a positive electrode active material. The negative electrode plate 2 has a negative electrode current collector and a negative electrode mixture layer formed on the negative electrode current collector and containing a negative electrode active material.

　正極板１は、正極リード６を介して、封口体１０（具体的には、封口体１０を構成する金属板１１）に接続されている。負極板２は、負極リード７を介して、電池ケース５の底部に接続されている。 The positive electrode plate 1 is connected to a sealing body 10 (specifically, a metal plate 11 constituting the sealing body 10) via a positive electrode lead 6. The negative electrode plate 2 is connected to the bottom of the battery case 5 via the negative electrode lead 7.

　電極群４の上端（電極群４における電池ケース５の開口部側の端）の上には、絶縁板８が配設されている。一方、電極群４の下端（電極群４における電池ケース５の底部側の端）の上には、絶縁板９が配設されている。 An insulating plate 8 is disposed on the upper end of the electrode group 4 (the end on the opening side of the battery case 5 in the electrode group 4). On the other hand, an insulating plate 9 is disposed on the lower end of the electrode group 4 (the end of the electrode group 4 on the bottom side of the battery case 5).

　電池ケース５の側面部には、電池ケース５の内側に向かって凹む凹み部が形成されている。封口体１０は、ガスケット（第１のガスケット）１７を介して、凹み部の上に配設されている。電池ケース５の開口端部は、ガスケット１７を介して、封口体１０の周縁部にかしめられている。電池ケース５の開口部は、電池ケース５と封口体１０との間にガスケット１７を介して、封口体１０により封口されている。充分な気密性の維持を考慮して、凹み部の内側面には、封止剤が塗布されていてもよい。 On the side surface of the battery case 5, a dent that is recessed toward the inside of the battery case 5 is formed. The sealing body 10 is disposed on the recessed portion via a gasket (first gasket) 17. The opening end of the battery case 5 is caulked to the peripheral edge of the sealing body 10 via the gasket 17. The opening of the battery case 5 is sealed by the sealing body 10 via the gasket 17 between the battery case 5 and the sealing body 10. In consideration of maintaining sufficient airtightness, a sealant may be applied to the inner surface of the recess.

　電池ケース５は、凹み部と、ガスケット１７を介して封口体１０の周縁部にかしめられたかしめ部（即ち、開口端部）とを有している。電池ケース５のかしめ部の断面形状は、図１に示すように、Ｃ字状である。本明細書において、「電池ケース５のかしめ部」とは、電池ケース５をかしめる時に曲げられた部分をいう。凹み部を形成する前の電池ケースは、有底筒状である。 The battery case 5 has a recessed portion and a caulking portion (that is, an opening end portion) that is caulked to the peripheral edge portion of the sealing body 10 via the gasket 17. The cross-sectional shape of the caulking portion of the battery case 5 is C-shaped as shown in FIG. In this specification, the “caulking part of the battery case 5” refers to a bent part when the battery case 5 is caulked. The battery case before forming the recess has a bottomed cylindrical shape.

　封口体１０は、金属板１１と、金属板１１の上に配設された弁板（第１の弁板）１２と、弁板１２の上に配設された弁板（第２の弁板）１４と、弁板１４の上に配設された環状のＰＴＣ（Positive Temperature Coefficient）素子１５と、ＰＴＣ素子１５の上に配設され且つ正極端子を兼ねるキャップ１６と、弁板１２の周縁部と弁板１４の周縁部との間に介在するガスケット（第２のガスケット）１３とを有している。なお、「ＰＴＣ素子」とは、正の温度係数を持つ素子であり、温度上昇により内部抵抗が増大する素子である。 The sealing body 10 includes a metal plate 11, a valve plate (first valve plate) 12 disposed on the metal plate 11, and a valve plate (second valve plate) disposed on the valve plate 12. ) 14, an annular PTC (Positive TemperatureefficientCoefficient) element 15 disposed on the valve plate 14, a cap 16 disposed on the PTC element 15 and also serving as a positive electrode terminal, and a peripheral portion of the valve plate 12 And a gasket (second gasket) 13 interposed between the peripheral portion of the valve plate 14. The “PTC element” is an element having a positive temperature coefficient, and an internal resistance increases as the temperature rises.

　金属板１１の周縁部は、ガスケット１３を介して、キャップ１６の周縁部にかしめられている。このように、金属板１１と、弁板１２と、ガスケット１３と、弁板１４と、ＰＴＣ素子１５と、キャップ１６とは、一体に形成されている。 The peripheral edge of the metal plate 11 is caulked to the peripheral edge of the cap 16 via the gasket 13. Thus, the metal plate 11, the valve plate 12, the gasket 13, the valve plate 14, the PTC element 15, and the cap 16 are integrally formed.

　キャップ１４は、ＰＴＣ素子１５に当接する部分と、上側に突出する突出部とを有している。なお、本明細書において、「上側」とは、電極群４の捲回軸が延びる方向のうち、電池ケース５の開口部側に向かう方向をいう。 The cap 14 has a portion that contacts the PTC element 15 and a protruding portion that protrudes upward. In the present specification, “upper side” refers to a direction toward the opening side of the battery case 5 among directions in which the winding axis of the electrode group 4 extends.

　金属板１１は、周縁部（即ち、ガスケット１３を介してキャップ１６の周縁部にかしめられたかしめ部）と、弁板１２に当接する部分と、下側に突出する突出部とを有している。なお、本明細書において、「下側」とは、電極群４の捲回軸が延びる方向のうち、電池ケース５の底部側に向かう方向をいう。 The metal plate 11 has a peripheral portion (that is, a caulking portion that is caulked to the peripheral portion of the cap 16 via the gasket 13), a portion that contacts the valve plate 12, and a protruding portion that protrudes downward. Yes. In the present specification, “lower side” refers to a direction toward the bottom side of the battery case 5 in a direction in which the winding axis of the electrode group 4 extends.

　金属板１１のかしめ部（即ち、周縁部）の断面形状は、図１に示すように、Ｌ字状である。本明細書において、「金属板１１のかしめ部」とは、金属板１１をかしめる時に曲げられた部分をいう。かしめる前の金属板の周縁部は、板状である。 The cross-sectional shape of the caulking portion (that is, the peripheral portion) of the metal plate 11 is L-shaped as shown in FIG. In this specification, the “caulking portion of the metal plate 11” refers to a portion bent when the metal plate 11 is caulked. The peripheral part of the metal plate before caulking is plate-shaped.

　弁板１２の中央部と、弁板１４の中央部とは、互いに当接している。弁板１２，１４は、厚みが薄い薄肉部を有している。 The central part of the valve plate 12 and the central part of the valve plate 14 are in contact with each other. The valve plates 12 and 14 have thin portions with a small thickness.

　キャップ１６には、電池外と連通する開口部が形成されている。金属板１１には、開口部が形成されている。絶縁板８には、開口部が形成されている。 The cap 16 has an opening communicating with the outside of the battery. An opening is formed in the metal plate 11. An opening is formed in the insulating plate 8.

　例えば電池内にガスが発生した場合、電池内に発生したガスは、次のようにして、電池外に排気される。電池内にガスが発生し、電池内の圧力が上昇し所定圧力を超えると、弁板１２，１４の薄肉部が破断する。これにより、電池内に発生したガスは、絶縁板８の開口部、金属板１１の開口部、弁板１２の破断部、弁板１４の破断部及びキャップ１６の開口部を通って、電池外に排気される。 For example, when gas is generated in the battery, the gas generated in the battery is exhausted out of the battery as follows. When gas is generated in the battery and the pressure in the battery rises and exceeds a predetermined pressure, the thin portions of the valve plates 12 and 14 break. As a result, the gas generated in the battery passes through the opening of the insulating plate 8, the opening of the metal plate 11, the rupture of the valve plate 12, the rupture of the valve plate 14 and the opening of the cap 16. Exhausted.

　図１に示すように、封口体１０の周縁部（具体的には、封口体１０を構成する金属板１１のかしめ部）と、電池ケース５のかしめ部との間には、絶縁板１８が配設されている。図２に示すように、絶縁板１８は、リング状である。 As shown in FIG. 1, an insulating plate 18 is interposed between the peripheral portion of the sealing body 10 (specifically, the caulking portion of the metal plate 11 constituting the sealing body 10) and the caulking portion of the battery case 5. It is arranged. As shown in FIG. 2, the insulating plate 18 has a ring shape.

　本実施形態の場合、絶縁板１８は、金属板１１のかしめ部の上面に当接している。電池ケース５の開口端部（即ち、かしめ部）は、電池ケース５側から順にガスケット１７及び絶縁板１８を介して、封口体１０の周縁部（具体的には、封口体１０を構成する金属板１１のかしめ部）にかしめられている。 In the case of this embodiment, the insulating plate 18 is in contact with the upper surface of the caulking portion of the metal plate 11. The opening end portion (that is, the caulking portion) of the battery case 5 is connected to the peripheral portion of the sealing body 10 (specifically, the metal constituting the sealing body 10) via the gasket 17 and the insulating plate 18 in order from the battery case 5 side. It is caulked to the caulking portion of the plate 11.

　リング状の絶縁板１８の内端面は、図１に示すように、電池ケース５のかしめ部の端面よりも、内側（言い換えれば、電極群４の捲回軸側）に位置していることが好ましい。 As shown in FIG. 1, the inner end surface of the ring-shaped insulating plate 18 is located on the inner side (in other words, the winding axis side of the electrode group 4) than the end surface of the caulking portion of the battery case 5. preferable.

　絶縁板１８は、ガスケット１７の材料よりも高い融点を持つ高融点材料からなることが好ましい。具体的には例えば、ガスケット１７がＰＰ（polypropylene，ポリプロピレン）からなる場合、絶縁板１８は、例えば、ＰＦＡ（polytetrafluoroethylene -co-perfluoropropylvinylether，テトラフルオロエチレン・パーフルオロアルキルビニルエーテル共重合体）、ＰＴＦＥ（polytetrafluoroethylene，ポリテトラフルオロエチレン）、ＰＰＳ（polyphenylene sulfide，ポリフェニレンサルファイド）、ＰＢＴ（polybutylene terephthalate, ポリブチレンテレフタレート）及びＰｌ（polyimide，ポリイミド）からなることが好ましい。 The insulating plate 18 is preferably made of a high melting point material having a higher melting point than the material of the gasket 17. Specifically, for example, when the gasket 17 is made of PP (polypropylene), the insulating plate 18 is made of, for example, PFA (polytetrafluoroethylene-co-perfluoropropylvinylether), PTFE (polytetrafluoroethylene). , Polytetrafluoroethylene), PPS (polyphenylene sulfide), PBT (polybutylene terephthalate) and Pl (polyimide).

　絶縁板１８は、ガスケット１７の材料よりも低い機械的強度（引っ張り強度）を持つ高融点材料からなることがより好ましい。具体的には例えば、ガスケット１７がＰＰからなる場合、絶縁板１８は、例えば、ＰＦＡ又はＰＴＦＥからなることがより好ましい。 The insulating plate 18 is more preferably made of a high melting point material having a mechanical strength (tensile strength) lower than that of the gasket 17. Specifically, for example, when the gasket 17 is made of PP, the insulating plate 18 is more preferably made of, for example, PFA or PTFE.

　本実施形態によると、封口体１０の周縁部（具体的には、封口体１０を構成する金属板１１のかしめ部）と、電池ケース５のかしめ部との間に、金属板１１のかしめ部の上面に当接する絶縁板１８が配設されており、絶縁板１８は、ガスケット１７の材料よりも高い融点を持つ高融点材料からなる。このため、電池が高温環境下に晒されることによりガスケット１７が溶融することがあっても、絶縁板１８が溶融することはないため、金属板１１のかしめ部の上面と電池ケース５のかしめ部とが接触することを防止することができる。従って、封口体１０（具体的には、封口体１０を構成する金属板１１）と電池ケース５とが短絡することを防止することができる。 According to the present embodiment, the caulking portion of the metal plate 11 between the peripheral portion of the sealing body 10 (specifically, the caulking portion of the metal plate 11 constituting the sealing body 10) and the caulking portion of the battery case 5. An insulating plate 18 that abuts on the upper surface is disposed, and the insulating plate 18 is made of a high melting point material having a higher melting point than the material of the gasket 17. For this reason, even if the gasket 17 is melted when the battery is exposed to a high temperature environment, the insulating plate 18 is not melted. Therefore, the upper surface of the caulking portion of the metal plate 11 and the caulking portion of the battery case 5 are not melted. Can be prevented from coming into contact with each other. Therefore, it is possible to prevent the sealing body 10 (specifically, the metal plate 11 constituting the sealing body 10) and the battery case 5 from being short-circuited.

　さらに、絶縁板１８が、ガスケット１７の材料よりも低い強度を持つ高融点材料からなる。これにより、電池の製造時（具体的には、電池ケース５の開口端部を、電池ケース５側から順にガスケット１７及び絶縁板１８を介して、封口体１０の周縁部にかしめる時）に、ガスケット１７及び絶縁板１８が変形することがあっても、ガスケット１７が変形するよりも前に、ガスケット１７よりも低い強度を有する絶縁板１８が変形するため、ガスケット１７の変形量を抑制することができる。従って、電池ケース５をかしめる時に、ガスケット１７にクラックが生じること、及びガスケット１７が割れることを防止することができる。 Furthermore, the insulating plate 18 is made of a high melting point material having lower strength than the material of the gasket 17. Thereby, when the battery is manufactured (specifically, when the open end of the battery case 5 is caulked to the peripheral edge of the sealing body 10 via the gasket 17 and the insulating plate 18 in this order from the battery case 5 side). Even if the gasket 17 and the insulating plate 18 are deformed, the insulating plate 18 having a lower strength than the gasket 17 is deformed before the gasket 17 is deformed, so that the deformation amount of the gasket 17 is suppressed. be able to. Therefore, when the battery case 5 is caulked, it is possible to prevent the gasket 17 from cracking and the gasket 17 from cracking.

　（第１の実施形態の第１の変形例）
　以下に、本発明の第１の実施形態の第１の変形例に係る二次電池について、図３及び図４を参照しながら説明する。図３は、本変形例に係る二次電池の構成を示す断面図である。図４は、絶縁板の構成を示す斜視図である。図３において、第１の実施形態と同様の構成要素には、図１と同一の符号を付す。従って、本変形例では、第１の実施形態と同様の説明を適宜省略する。 (First modification of the first embodiment)
Hereinafter, a secondary battery according to a first modification of the first embodiment of the present invention will be described with reference to FIGS. 3 and 4. FIG. 3 is a cross-sectional view showing the configuration of the secondary battery according to this modification. FIG. 4 is a perspective view showing the configuration of the insulating plate. In FIG. 3, the same components as those in the first embodiment are denoted by the same reference numerals as those in FIG. Therefore, in this modification, the description similar to that of the first embodiment is omitted as appropriate.

　本変形例と第１の実施形態との相違点は、以下の点である。 The differences between this modification and the first embodiment are as follows.

　第１の実施形態では、図１に示すように、リング状の絶縁板１８は、金属板１１のかしめ部の上面に当接している。 In the first embodiment, as shown in FIG. 1, the ring-shaped insulating plate 18 is in contact with the upper surface of the caulking portion of the metal plate 11.

　これに対し、本変形例では、図３に示すように、リング状の絶縁板１８Ｘは、金属板１１のかしめ部の上面及び側面に当接している。絶縁板１８Ｘは、平坦部と、平坦部の外端部から下側に突出する突出部とを有している。平坦部は、金属板１１のかしめ部の上面に当接している。突出部は、金属板１１のかしめ部の側面に当接している。絶縁板１８Ｘの断面形状は、Ｌ字状である。 On the other hand, in this modification, as shown in FIG. 3, the ring-shaped insulating plate 18 </ b> X is in contact with the upper surface and the side surface of the caulking portion of the metal plate 11. The insulating plate 18X has a flat portion and a protruding portion that protrudes downward from the outer end portion of the flat portion. The flat portion is in contact with the upper surface of the caulking portion of the metal plate 11. The protruding portion is in contact with the side surface of the caulking portion of the metal plate 11. The cross-sectional shape of the insulating plate 18X is L-shaped.

　既述の通り、ガスケットの溶融により封口体の周縁部の上面と電池ケースのかしめ部とが接触する確率は、ガスケットの溶融により封口体の側面と電池ケースとが接触する確率よりも、高い。そこで、第１の実施形態では、図１に示すように、接触確率が比較的高い領域に、絶縁板１８を配設する。具体的には、封口体１０の周縁部（具体的には、封口体１０を構成する金属板１１のかしめ部）の上面と、電池ケース５のかしめ部との間に、金属板１１のかしめ部の上面に当接する絶縁板１８を配設する。 As described above, the probability that the upper surface of the peripheral portion of the sealing body and the caulking portion of the battery case are in contact with each other due to melting of the gasket is higher than the probability that the side surface of the sealing body and the battery case are in contact with each other due to melting of the gasket. Therefore, in the first embodiment, as shown in FIG. 1, the insulating plate 18 is disposed in a region where the contact probability is relatively high. Specifically, the metal plate 11 is caulked between the upper surface of the peripheral portion of the sealing body 10 (specifically, the caulking portion of the metal plate 11 constituting the sealing body 10) and the caulking portion of the battery case 5. An insulating plate 18 that contacts the upper surface of the part is disposed.

　これに対し、本変形例では、図３に示すように、接触確率が比較的高い領域にだけでなく、接触確率が比較的低い領域にも、絶縁板１８Ｘを配設する。具体的には、金属板１１のかしめ部の上面と電池ケース５のかしめ部との間にだけでなく、金属板１１のかしめ部の側面と電池ケース５のかしめ部との間にも、金属板１１のかしめ部の上面及び側面に当接する絶縁板１８Ｘを配設する。 On the other hand, in this modification, as shown in FIG. 3, the insulating plate 18X is disposed not only in the region where the contact probability is relatively high but also in the region where the contact probability is relatively low. Specifically, not only between the upper surface of the caulking portion of the metal plate 11 and the caulking portion of the battery case 5, but also between the side surface of the caulking portion of the metal plate 11 and the caulking portion of the battery case 5. An insulating plate 18X that contacts the upper and side surfaces of the caulking portion of the plate 11 is disposed.

　本変形例によると、第１の実施形態と同様の効果を得ることができる。具体的には、ガスケット１７が溶融することがあっても、ガスケット１７よりも高い融点を有する絶縁板１８Ｘが溶融することはないため、金属板１１のかしめ部の上面と電池ケース５のかしめ部とが接触することを防止することができる。従って、封口体１０（具体的には、封口体１０を構成する金属板１１）と電池ケース５とが短絡することを防止することができる。さらに、絶縁板１８Ｘが、ガスケット１７の材料よりも低い強度を持つ高融点材料からなることにより、電池ケース５をかしめる時に、ガスケット１７にクラックが生じること、及びガスケット１７が割れることを防止することができる。 According to this modification, the same effect as that of the first embodiment can be obtained. Specifically, even if the gasket 17 is melted, the insulating plate 18X having a melting point higher than that of the gasket 17 is not melted. Therefore, the upper surface of the caulking portion of the metal plate 11 and the caulking portion of the battery case 5 are not melted. Can be prevented from coming into contact with each other. Therefore, it is possible to prevent the sealing body 10 (specifically, the metal plate 11 constituting the sealing body 10) and the battery case 5 from being short-circuited. Further, the insulating plate 18X is made of a high melting point material having lower strength than the material of the gasket 17, thereby preventing the gasket 17 from cracking and the gasket 17 from cracking when the battery case 5 is caulked. be able to.

　さらに、絶縁板１８Ｘは、金属板１１のかしめ部の側面に当接する突出部を有している。これにより、金属板１１のかしめ部の側面と電池ケース５のかしめ部とが接触することを防止することができる。従って、封口体１０（具体的には、封口体１０を構成する金属板１１）と電池ケース５とが短絡することをさらに防止することができる。 Furthermore, the insulating plate 18X has a protruding portion that contacts the side surface of the caulking portion of the metal plate 11. Thereby, it can prevent that the side surface of the crimping part of the metal plate 11 and the crimping part of the battery case 5 contact. Therefore, it is possible to further prevent the sealing body 10 (specifically, the metal plate 11 constituting the sealing body 10) and the battery case 5 from being short-circuited.

　（第１の実施形態の第２の変形例）
　以下に、本発明の第１の実施形態の第２の変形例に係る二次電池について、図５及び図６を参照しながら説明する。図５は、本変形例に係る二次電池の構成を示す断面図である。図６は、絶縁板の構成を示す斜視図である。図５において、第１の実施形態と同様の構成要素には、図１と同一の符号を付す。従って、本変形例では、第１の実施形態と同様の説明を適宜省略する。 (Second modification of the first embodiment)
Hereinafter, a secondary battery according to a second modification of the first embodiment of the present invention will be described with reference to FIGS. 5 and 6. FIG. 5 is a cross-sectional view showing the configuration of the secondary battery according to this modification. FIG. 6 is a perspective view showing the configuration of the insulating plate. In FIG. 5, the same components as those in the first embodiment are denoted by the same reference numerals as those in FIG. Therefore, in this modification, the description similar to that of the first embodiment is omitted as appropriate.

　本変形例と第１の実施形態との相違点は、以下の点である。 The differences between this modification and the first embodiment are as follows.

　第１の実施形態では、図１に示すように、リング状の絶縁板１８は、金属板１１のかしめ部の上面に当接している。 In the first embodiment, as shown in FIG. 1, the ring-shaped insulating plate 18 is in contact with the upper surface of the caulking portion of the metal plate 11.

　これに対し、本変形例では、図６に示すように、リング状の絶縁板１８Ｙは、平坦部と、平坦部の内端部から上側に突出する突出部とを有している。図５に示すように、平坦部は、金属板１１のかしめ部の上面に当接している。突出部は、キャップ１４における突出部の側面に当接している。絶縁板１８Ｙの断面形状は、Ｌ字状である。 On the other hand, in this modification, as shown in FIG. 6, the ring-shaped insulating plate 18Y has a flat portion and a protruding portion protruding upward from the inner end portion of the flat portion. As shown in FIG. 5, the flat portion is in contact with the upper surface of the caulking portion of the metal plate 11. The protruding portion is in contact with the side surface of the protruding portion of the cap 14. The cross-sectional shape of the insulating plate 18Y is L-shaped.

　本変形例によると、第１の実施形態と同様の効果を得ることができる。具体的には、ガスケット１７が溶融することがあっても、ガスケット１７よりも高い融点を有する絶縁板１８Ｙが溶融することはないため、金属板１１のかしめ部の上面と電池ケース５のかしめ部とが接触することを防止することができる。従って、封口体１０（具体的には、封口体１０を構成する金属板１１）と電池ケース５とが短絡することを防止することができる。さらに、絶縁板１８Ｙが、ガスケット１７の材料よりも低い強度を持つ高融点材料からなることにより、電池ケース５をかしめる時に、ガスケット１７にクラックが生じること、及びガスケット１７が割れることを防止することができる。 According to this modification, the same effect as that of the first embodiment can be obtained. Specifically, even if the gasket 17 is melted, the insulating plate 18Y having a melting point higher than that of the gasket 17 is not melted. Therefore, the upper surface of the caulking portion of the metal plate 11 and the caulking portion of the battery case 5 are not melted. Can be prevented from coming into contact with each other. Therefore, it is possible to prevent the sealing body 10 (specifically, the metal plate 11 constituting the sealing body 10) and the battery case 5 from being short-circuited. Further, since the insulating plate 18Y is made of a high melting point material having lower strength than the material of the gasket 17, it is possible to prevent the gasket 17 from cracking and the gasket 17 from cracking when the battery case 5 is caulked. be able to.

　さらに、絶縁板１８Ｙは、キャップ１６における突出部の側面に当接する突出部を有している。これにより、電池ケース５のかしめ部に異物が接触することがあっても、電池ケース５のかしめ部に接触する異物が、キャップ１６における突出部の側面と接触することを防止することができる。従って、異物によりキャップ１６と電池ケース５とが短絡することを防止することができる。 Furthermore, the insulating plate 18Y has a protruding portion that contacts the side surface of the protruding portion of the cap 16. As a result, even if foreign matter comes into contact with the caulking portion of the battery case 5, foreign matter that comes into contact with the caulking portion of the battery case 5 can be prevented from coming into contact with the side surface of the protruding portion of the cap 16. Therefore, it is possible to prevent the cap 16 and the battery case 5 from being short-circuited by the foreign matter.

　（第２の実施形態）
　以下に、本発明の第２の実施形態に係る二次電池について、図７を参照しながら説明する。図７は、本実施形態に係る二次電池の構成を示す断面図である。図７において、第１の実施形態と同様の構成要素には、図１と同一の符号を付す。従って、本実施形態では、第１の実施形態と同様の説明を適宜省略する。 (Second Embodiment)
The secondary battery according to the second embodiment of the present invention will be described below with reference to FIG. FIG. 7 is a cross-sectional view showing the configuration of the secondary battery according to the present embodiment. In FIG. 7, the same components as those in the first embodiment are denoted by the same reference numerals as those in FIG. Therefore, in this embodiment, the same description as that of the first embodiment is omitted as appropriate.

　本実施形態と第１の実施形態との相違点は、以下の点である。 The difference between this embodiment and the first embodiment is as follows.

　第１の実施形態では、図１に示すように、封口体１０の周縁部（具体的には、封口体１０を構成する金属板１１のかしめ部）と電池ケース５のかしめ部との間に配設された絶縁板１８は、金属板１１のかしめ部に当接している。電池ケース５の開口端部（即ち、かしめ部）は、電池ケース５側から順にガスケット１７及び絶縁板１８を介して、封口体１０の周縁部にかしめられている。 In the first embodiment, as shown in FIG. 1, between the peripheral portion of the sealing body 10 (specifically, the caulking portion of the metal plate 11 constituting the sealing body 10) and the caulking portion of the battery case 5. The disposed insulating plate 18 is in contact with the caulking portion of the metal plate 11. The opening end portion (that is, the caulking portion) of the battery case 5 is caulked to the peripheral edge portion of the sealing body 10 via the gasket 17 and the insulating plate 18 in order from the battery case 5 side.

　これに対し、第２の実施形態では、図７に示すように、金属板１１のかしめ部と電池ケース５のかしめ部との間に配設された絶縁板１８Ｚは、電池ケース５のかしめ部に当接している。電池ケース５の開口端部は、電池ケース５側から順に絶縁板１８Ｚ及びガスケット１７を介して、封口体１０の周縁部にかしめられている。絶縁板１８Ｚは、電池ケース５のかしめ部に沿った形状を有している。 On the other hand, in the second embodiment, as shown in FIG. 7, the insulating plate 18 </ b> Z disposed between the caulking portion of the metal plate 11 and the caulking portion of the battery case 5 is used as the caulking portion of the battery case 5. Abut. The opening end portion of the battery case 5 is caulked to the peripheral edge portion of the sealing body 10 via the insulating plate 18Z and the gasket 17 in order from the battery case 5 side. The insulating plate 18 </ b> Z has a shape along the caulking portion of the battery case 5.

　リング状の絶縁板１８Ｚの内端面は、図７に示すように、電池ケース５のかしめ部の端面よりも、内側（言い換えれば、電極群４の捲回軸側）に位置していることが好ましい。 As shown in FIG. 7, the inner end surface of the ring-shaped insulating plate 18 </ b> Z is located on the inner side (in other words, the winding axis side of the electrode group 4) than the end surface of the caulking portion of the battery case 5. preferable.

　本実施形態によると、第１の実施形態と同様の効果を得ることができる。具体的には、ガスケット１７が溶融することがあっても、ガスケット１７よりも高い融点を有する絶縁板１８Ｚが溶融することはないため、金属板１１のかしめ部の上面と電池ケース５のかしめ部とが接触することを防止することができる。従って、封口体１０（具体的には、封口体１０を構成する金属板１１）と電池ケース５とが短絡することを防止することができる。さらに、絶縁板１８Ｚが、ガスケット１７の材料よりも低い強度を持つ高融点材料からなることにより、電池ケース５をかしめる時に、ガスケット１７にクラックが生じること、及びガスケット１７が割れることを防止することができる。 According to this embodiment, the same effect as that of the first embodiment can be obtained. Specifically, even if the gasket 17 is melted, the insulating plate 18Z having a melting point higher than that of the gasket 17 is not melted. Therefore, the upper surface of the caulking portion of the metal plate 11 and the caulking portion of the battery case 5 are not melted. Can be prevented from coming into contact with each other. Therefore, it is possible to prevent the sealing body 10 (specifically, the metal plate 11 constituting the sealing body 10) and the battery case 5 from being short-circuited. Furthermore, the insulating plate 18Z is made of a high melting point material having lower strength than the material of the gasket 17, thereby preventing the gasket 17 from cracking and the gasket 17 from cracking when the battery case 5 is caulked. be able to.

　なお、第１の実施形態及び第１，第２の変形例並びに第２の実施形態では、図１、図３、図５及び図７に示すように、封口体１０が、金属板１１と、弁板１２と、ガスケット１３と、弁板１４と、ＰＴＣ素子１５と、キャップ１６とを有し、金属板１１の周縁部が、ガスケット１３を介して、キャップ１６の周縁部にかしめられている場合を具体例に挙げて説明したが、本発明はこれに限定されるものではない。 In the first embodiment, the first and second modifications, and the second embodiment, as shown in FIGS. 1, 3, 5, and 7, the sealing body 10 includes a metal plate 11, It has a valve plate 12, a gasket 13, a valve plate 14, a PTC element 15, and a cap 16, and the peripheral portion of the metal plate 11 is caulked to the peripheral portion of the cap 16 via the gasket 13. Although cases have been described as specific examples, the present invention is not limited thereto.

　例えば、図８に示すように、封口体２０が、金属板２１と、弁板２２と、ガスケット２３と、弁板２４と、ＰＴＣ素子２５と、キャップ２６とを有し、金属板２１の周縁部が、ガスケット２３を介して、キャップ１６の周縁部にかしめられていなくてもよい。この場合、封口体２０の周縁部（具体的には、封口体２０を構成するキャップ２６の周縁部）と、電池ケース５のかしめ部との間に、キャップ２６の周縁部の上面に当接するリング状の絶縁板２８が配設されている。 For example, as shown in FIG. 8, the sealing body 20 includes a metal plate 21, a valve plate 22, a gasket 23, a valve plate 24, a PTC element 25, and a cap 26. The portion may not be caulked to the peripheral edge portion of the cap 16 via the gasket 23. In this case, the upper surface of the peripheral portion of the cap 26 is brought into contact between the peripheral portion of the sealing body 20 (specifically, the peripheral portion of the cap 26 constituting the sealing body 20) and the caulking portion of the battery case 5. A ring-shaped insulating plate 28 is provided.

　なお、この場合、キャップ２６の周縁部と電池ケース５のかしめ部との間に、キャップ２６の周縁部の上面に当接し、且つ、第１の実施形態の絶縁板１８と同様の形状を有する絶縁板２８が配設されている場合を具体例に挙げて説明したが、本発明はこれに限定されるものではない。第１に例えば、キャップの周縁部と電池ケースのかしめ部との間に、第１の実施形態の第１の変形例の絶縁板１８Ｘと同様の形状を有する絶縁板、即ち、キャップの周縁部の側面（キャップの端面）に当接する突出部を有する絶縁板が配設されていてもよい。第２に例えば、キャップの周縁部と電池ケースのかしめ部との間に、第１の実施形態の第２の変形例の絶縁板１８Ｙと同様の形状を有する絶縁板、即ち、キャップにおける突出部の側面に当接する突出部を有する絶縁板が配設されていてもよい。第３に例えば、キャップの周縁部と電池ケースのかしめ部との間に、電池ケースのかしめ部に当接し、且つ、第２の実施形態の絶縁板１８Ｚと同様の形状を有する絶縁板が配設されていてもよい。 In this case, the cap 26 and the caulking portion of the battery case 5 are in contact with the upper surface of the peripheral portion of the cap 26 and have the same shape as the insulating plate 18 of the first embodiment. Although the case where the insulating plate 28 is disposed has been described as a specific example, the present invention is not limited to this. First, for example, an insulating plate having the same shape as the insulating plate 18X of the first modified example of the first embodiment between the peripheral portion of the cap and the caulking portion of the battery case, that is, the peripheral portion of the cap An insulating plate having a projecting portion that comes into contact with the side surface (the end surface of the cap) may be disposed. Secondly, for example, an insulating plate having the same shape as the insulating plate 18Y of the second modified example of the first embodiment between the peripheral portion of the cap and the caulking portion of the battery case, that is, a protruding portion in the cap An insulating plate having a protruding portion that abuts on the side surface of the plate may be disposed. Third, for example, an insulating plate that is in contact with the caulking portion of the battery case and has the same shape as the insulating plate 18Z of the second embodiment is disposed between the peripheral portion of the cap and the caulking portion of the battery case. It may be provided.

　なお、第１の実施形態及び第１，第２の変形例並びに第２の実施形態では、図１、図３、図５及び図７に示すように、封口体１０が、金属板１１と、弁板１２と、ガスケット１３と、弁板１４と、ＰＴＣ素子１５と、キャップ１６とを有し、金属板１１の周縁部が、ガスケット１３を介して、キャップ１６の周縁部にかしめられている場合を具体例に挙げて説明したが、本発明はこれに限定されるものではない。封口体は、少なくとも、金属板と、金属板の上方に配設されたキャップとを有し、金属板の周縁部が、キャップの周縁部にかしめられていればよい。 In the first embodiment, the first and second modifications, and the second embodiment, as shown in FIGS. 1, 3, 5, and 7, the sealing body 10 includes a metal plate 11, It has a valve plate 12, a gasket 13, a valve plate 14, a PTC element 15, and a cap 16, and the peripheral portion of the metal plate 11 is caulked to the peripheral portion of the cap 16 via the gasket 13. Although cases have been described as specific examples, the present invention is not limited thereto. The sealing body has at least a metal plate and a cap disposed above the metal plate, and the peripheral portion of the metal plate may be caulked to the peripheral portion of the cap.

　第１の実施形態及び第１，第２の変形例並びに第２の実施形態の場合、封口体１０が、弁板１２と、ガスケット１３と、弁板１４とを有する理由は、次のような理由による。電池内にガスが発生し、電池内の圧力が上昇し所定圧力を超えた時に、金属板１１とキャップ１６との間に流れる電流を遮断する機能を有することが好ましい。そこで、封口体１０は、電池内の圧力が所定圧力を超えた時に破断することが可能な薄肉部を有し、且つ、中央部同士が互いに当接する弁板１２，１４と、弁板１２の周縁部と弁板１４の周縁部との間に介在するガスケット１３とを有する。これにより、弁板１２，１４の薄肉部が破断した時に、弁板１２と弁板１４とが互いに離間するため、弁板１２，１４を介して電気的に接続する金属板１１とキャップ１６との間に流れる電流を遮断することができる。 In the case of the first embodiment, the first and second modifications, and the second embodiment, the reason why the sealing body 10 includes the valve plate 12, the gasket 13, and the valve plate 14 is as follows. Depending on the reason. It is preferable to have a function of cutting off the current flowing between the metal plate 11 and the cap 16 when gas is generated in the battery and the pressure in the battery rises and exceeds a predetermined pressure. Therefore, the sealing body 10 has a thin wall portion that can be broken when the pressure in the battery exceeds a predetermined pressure, and the central portions of the valve plates 12 and 14 are in contact with each other. The gasket 13 is interposed between the peripheral edge and the peripheral edge of the valve plate 14. Thus, when the thin portions of the valve plates 12 and 14 are broken, the valve plate 12 and the valve plate 14 are separated from each other. Therefore, the metal plate 11 and the cap 16 that are electrically connected via the valve plates 12 and 14 It is possible to cut off the current flowing between.

　第１の実施形態及び第１，第２の変形例並びに第２の実施形態の場合、封口体１０が、ＰＴＣ素子１５を有する理由は、次のような理由による。電池内の温度が上昇し所定温度を超えた時に、金属板１１とキャップ１６との間に流れる電流を遮断する機能を有することが好ましい。そこで、封口体１０は、金属板１１と電気的に接続する弁板１４とキャップ１６との間に介在し、且つ、電池内の温度が所定温度を超えた時に内部抵抗が増大することが可能なＰＴＣ素子１５を有する。これにより、ＰＴＣ素子１５の内部抵抗が増大した時に、弁板１４とキャップ１６との間に流れる電流が遮断されるため、弁板１４と電気的に接続する金属板１１とキャップ１６との間に流れる電流を遮断することができる。 In the case of the first embodiment, the first and second modifications, and the second embodiment, the reason why the sealing body 10 has the PTC element 15 is as follows. It is preferable that the battery has a function of interrupting current flowing between the metal plate 11 and the cap 16 when the temperature in the battery rises and exceeds a predetermined temperature. Therefore, the sealing body 10 is interposed between the valve plate 14 electrically connected to the metal plate 11 and the cap 16, and the internal resistance can be increased when the temperature in the battery exceeds a predetermined temperature. PTC element 15 is included. As a result, when the internal resistance of the PTC element 15 increases, the current flowing between the valve plate 14 and the cap 16 is cut off, so that the gap between the metal plate 11 and the cap 16 electrically connected to the valve plate 14 is reduced. It is possible to cut off the current flowing through the.

　以上から判るように、封口体は、必ずしも、２つの弁板１２，１４と、ガスケット１３とを有している必要はない。例えば、封口体は、金属板と、金属板の上に配設されたＰＴＣ素子と、ＰＴＣ素子の上に配設されたキャップとを有していてもよい。 As can be seen from the above, the sealing body does not necessarily need to have the two valve plates 12 and 14 and the gasket 13. For example, the sealing body may have a metal plate, a PTC element disposed on the metal plate, and a cap disposed on the PTC element.

　封口体は、必ずしも、ＰＴＣ素子１５を有している必要はない。例えば、封口体は、金属板と、金属板の上に配設された第１の弁板と、第１の弁板の上に配設された第２の弁板と、第２の弁板の上に配設されたキャップと、第１の弁板の周縁部と第２の弁板の周縁部との間に介在するガスケットとを有していてもよい。 The sealing body does not necessarily need to have the PTC element 15. For example, the sealing body includes a metal plate, a first valve plate disposed on the metal plate, a second valve plate disposed on the first valve plate, and a second valve plate. You may have the cap arrange | positioned above and the gasket interposed between the peripheral part of a 1st valve plate, and the peripheral part of a 2nd valve plate.

　なお、第１の実施形態の第１の変形例では、図３に示すように、絶縁板１８Ｘの突出部が、金属板１１のかしめ部の側面の一部に当接している場合、言い換えれば、絶縁板１８Ｘの突出部が、金属板１１のかしめ部の側面と電池ケース５のかしめ部との間に配設されている場合を具体例に挙げて説明したが、本発明はこれに限定されるものではない。例えば、絶縁板の突出部は、金属板のかしめ部の側面の全部に当接していてもよい。 In addition, in the 1st modification of 1st Embodiment, as shown in FIG. 3, when the protrusion part of the insulating board 18X is contact | abutting to a part of side surface of the crimping part of the metal plate 11, in other words, Although the case where the protruding portion of the insulating plate 18X is disposed between the side surface of the caulking portion of the metal plate 11 and the caulking portion of the battery case 5 has been described as a specific example, the present invention is not limited thereto. Is not to be done. For example, the protruding portion of the insulating plate may be in contact with the entire side surface of the caulking portion of the metal plate.

　本実施形態では、二次電池として、リチウムイオン二次電池を用いた場合を具体例に挙げて説明したが、本発明はこれに限定されるものではない。 In the present embodiment, the case where a lithium ion secondary battery is used as the secondary battery has been described as a specific example, but the present invention is not limited to this.

　本発明は、ガスケットが溶融することがあっても、封口体と電池ケースとが短絡することを防止することができ、電池ケースの開口部がガスケットを介して封口体により封口された二次電池に有用である。 The present invention can prevent the sealing body and the battery case from being short-circuited even if the gasket is melted, and the secondary battery in which the opening of the battery case is sealed by the sealing body via the gasket Useful for.

　１　　正極板
　２　　負極板
　３　　セパレータ
　４　　電極群
　５　　電池ケース
　６　　正極リード
　７　　負極リード
　８　　絶縁板
　９　　絶縁板
　１０　　封口体
　１１　　金属板
　１２　　弁板（第１の弁板）
　１３　　ガスケット（第２のガスケット）
　１４　　弁板（第２の弁板）
　１５　　ＰＴＣ
　１６　　キャップ
　１７　　ガスケット（第１のガスケット）
　１８，１８Ｘ，１８Ｙ　　絶縁板
　２０　　封口体
　２１　　金属板
　２２　　弁板
　２３　　ガスケット
　２４　　弁板
　２５　　ＰＴＣ
　２６　　キャップ
　２８　　絶縁板 DESCRIPTION OF SYMBOLS 1 Positive electrode plate 2 Negative electrode plate 3 Separator 4 Electrode group 5 Battery case 6 Positive electrode lead 7 Negative electrode lead 8 Insulating plate 9 Insulating plate 10 Sealing body 11 Metal plate 12 Valve plate (1st valve plate)
13 Gasket (second gasket)
14 Valve plate (second valve plate)
15 PTC
16 Cap 17 Gasket (first gasket)
18, 18X, 18Y Insulating plate 20 Sealing body 21 Metal plate 22 Valve plate 23 Gasket 24 Valve plate 25 PTC
26 Cap 28 Insulation plate

Claims (10)

　正極板及び負極板がそれらの間にセパレータを介して捲回された電極群を有する二次電池であって、
　前記電極群を収容する円筒形の電池ケースと、
　前記電池ケースとの間に第１のガスケットを介して、前記電池ケースの開口部を封口する封口体とを備え、
　前記電池ケースの開口端部は、前記第１のガスケットを介して、前記封口体の周縁部にかしめられており、
　前記封口体の前記周縁部と前記電池ケースのかしめ部との間には、リング状の絶縁板が配設されていることを特徴とする二次電池。 A secondary battery having an electrode group in which a positive electrode plate and a negative electrode plate are wound through a separator therebetween,
A cylindrical battery case for housing the electrode group;
A sealing body for sealing the opening of the battery case via a first gasket between the battery case,
The opening end of the battery case is caulked to the peripheral edge of the sealing body via the first gasket,
A secondary battery, wherein a ring-shaped insulating plate is disposed between the peripheral edge portion of the sealing body and the caulking portion of the battery case. 　請求項１に記載の二次電池において、
　前記絶縁板は、前記封口体の前記周縁部に当接していることを特徴とする二次電池。 The secondary battery according to claim 1,
The secondary battery, wherein the insulating plate is in contact with the peripheral edge of the sealing body. 　請求項１に記載の二次電池において、
　前記封口体は、少なくとも、金属板と、前記金属板の上方に配設されたキャップとを有し、
　前記正極板及び前記負極板のうちの一方の極板は、リードを介して、前記金属板に接続されており、
　前記キャップは、前記一方の極板の端子を兼ねており、
　前記金属板の周縁部は、前記キャップの周縁部にかしめられており、
　前記絶縁板は、前記金属板のかしめ部と前記電池ケースの前記かしめ部との間に配設されていることを特徴とする二次電池。 The secondary battery according to claim 1,
The sealing body has at least a metal plate and a cap disposed above the metal plate,
One of the positive electrode plate and the negative electrode plate is connected to the metal plate via a lead,
The cap also serves as a terminal of the one electrode plate,
The peripheral part of the metal plate is caulked to the peripheral part of the cap,
The secondary battery is characterized in that the insulating plate is disposed between a caulking portion of the metal plate and the caulking portion of the battery case. 　請求項３に記載の二次電池において、
　前記絶縁板は、前記金属板の前記かしめ部に当接していることを特徴とする二次電池。 The secondary battery according to claim 3,
The secondary battery is characterized in that the insulating plate is in contact with the caulking portion of the metal plate. 　請求項４に記載の二次電池において、
　前記絶縁板は、
　　前記金属板の前記かしめ部に当接する平坦部と、
　　前記平坦部の内端部から突出し、且つ、前記キャップにおける突出部の側面に当接する突出部とを有していることを特徴とする二次電池。 The secondary battery according to claim 4,
The insulating plate is
A flat portion in contact with the caulking portion of the metal plate;
A secondary battery comprising: a protruding portion protruding from an inner end portion of the flat portion and contacting a side surface of the protruding portion of the cap. 　請求項３に記載の二次電池において、
　前記封口体は、
　　前記金属板と、
　　前記金属板の上に配設された第１の弁板と、
　　前記第１の弁板の上に配設された第２の弁板と、
　　前記第２の弁板の上に配設された前記キャップとを有し、
　前記第１の弁板の周縁部と前記第２の弁板の周縁部との間には、第２のガスケットが介在しており、
　前記金属板の周縁部は、前記第２のガスケットを介して、前記キャップの周縁部にかしめられていることを特徴とする二次電池。 The secondary battery according to claim 3,
The sealing body is
The metal plate;
A first valve plate disposed on the metal plate;
A second valve plate disposed on the first valve plate;
The cap disposed on the second valve plate;
Between the peripheral edge of the first valve plate and the peripheral edge of the second valve plate, a second gasket is interposed,
The secondary battery according to claim 1, wherein a peripheral edge portion of the metal plate is caulked to a peripheral edge portion of the cap via the second gasket. 　請求項１に記載の二次電池において、
　前記絶縁板は、前記電池ケースの前記かしめ部に当接していることを特徴とする二次電池。 The secondary battery according to claim 1,
The secondary battery is characterized in that the insulating plate is in contact with the caulking portion of the battery case. 　請求項１に記載の二次電池において、
　前記絶縁板の融点は、前記第１のガスケットの融点よりも高いことを特徴とする二次電池。 The secondary battery according to claim 1,
The secondary battery according to claim 1, wherein a melting point of the insulating plate is higher than a melting point of the first gasket. 　請求項８に記載の二次電池において、
　前記絶縁板の強度は、前記第１のガスケットの強度よりも低いことを特徴とする二次電池。 The secondary battery according to claim 8,
The secondary battery is characterized in that the strength of the insulating plate is lower than the strength of the first gasket. 　請求項１に記載の二次電池において、
　前記絶縁板の内端面は、前記電池ケースの前記かしめ部の端面よりも、内側に位置していることを特徴とする二次電池。 The secondary battery according to claim 1,
The secondary battery is characterized in that an inner end surface of the insulating plate is located on an inner side than an end surface of the caulking portion of the battery case.
PCT/JP2013/004515 2012-07-26 2013-07-24 Secondary battery Ceased WO2014017091A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2012-165657 2012-07-26
JP2012165657 2012-07-26

Publications (1)

Publication Number Publication Date
WO2014017091A1 true WO2014017091A1 (en) 2014-01-30

Family

ID=49996917

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2013/004515 Ceased WO2014017091A1 (en) 2012-07-26 2013-07-24 Secondary battery

Country Status (1)

Country Link
WO (1) WO2014017091A1 (en)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109952665A (en) * 2017-05-22 2019-06-28 株式会社Lg化学 Cylindrical battery comprising an anti-corrosion gasket
CN110800132A (en) * 2017-07-20 2020-02-14 三洋电机株式会社 Cylindrical battery
CN111373565A (en) * 2017-10-11 2020-07-03 三星Sdi株式会社 Secondary battery
JP2022513751A (en) * 2019-06-18 2022-02-09 エルジー エナジー ソリューション リミテッド Cylindrical rechargeable battery containing a grooved gasket
WO2022138423A1 (en) 2020-12-22 2022-06-30 三洋電機株式会社 Hermetically sealed battery
US20230231243A1 (en) * 2018-06-05 2023-07-20 Lg Energy Solution, Ltd. Secondary Battery
WO2024162017A1 (en) * 2023-01-31 2024-08-08 パナソニックＩｐマネジメント株式会社 Power storage device
WO2025134690A1 (en) * 2023-12-21 2025-06-26 パナソニックＩｐマネジメント株式会社 Non-aqueous electrolyte secondary battery

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0332356U (en) * 1989-08-08 1991-03-28
JPH10294093A (en) * 1997-04-17 1998-11-04 Mitsubishi Cable Ind Ltd Insulating structure sealed battery
JP2002025509A (en) * 2000-07-04 2002-01-25 Matsushita Electric Ind Co Ltd Alkaline batteries
JP2002141028A (en) * 2000-10-31 2002-05-17 Sanyo Electric Co Ltd Sealed battery and its manufacturing method
WO2009119094A1 (en) * 2008-03-27 2009-10-01 パナソニック株式会社 Sealed battery
WO2009150791A1 (en) * 2008-06-09 2009-12-17 パナソニック株式会社 Battery

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0332356U (en) * 1989-08-08 1991-03-28
JPH10294093A (en) * 1997-04-17 1998-11-04 Mitsubishi Cable Ind Ltd Insulating structure sealed battery
JP2002025509A (en) * 2000-07-04 2002-01-25 Matsushita Electric Ind Co Ltd Alkaline batteries
JP2002141028A (en) * 2000-10-31 2002-05-17 Sanyo Electric Co Ltd Sealed battery and its manufacturing method
WO2009119094A1 (en) * 2008-03-27 2009-10-01 パナソニック株式会社 Sealed battery
WO2009150791A1 (en) * 2008-06-09 2009-12-17 パナソニック株式会社 Battery

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109952665A (en) * 2017-05-22 2019-06-28 株式会社Lg化学 Cylindrical battery comprising an anti-corrosion gasket
CN110800132A (en) * 2017-07-20 2020-02-14 三洋电机株式会社 Cylindrical battery
CN111373565A (en) * 2017-10-11 2020-07-03 三星Sdi株式会社 Secondary battery
EP3696873A4 (en) * 2017-10-11 2021-06-09 Samsung SDI Co., Ltd. Secondary battery
US11502359B2 (en) 2017-10-11 2022-11-15 Samsung Sdi Co., Ltd. Secondary battery
US20230231243A1 (en) * 2018-06-05 2023-07-20 Lg Energy Solution, Ltd. Secondary Battery
JP2022513751A (en) * 2019-06-18 2022-02-09 エルジー エナジー ソリューション リミテッド Cylindrical rechargeable battery containing a grooved gasket
JP7081771B2 (en) 2019-06-18 2022-06-07 エルジー エナジー ソリューション リミテッド Cylindrical rechargeable battery containing a grooved gasket
WO2022138423A1 (en) 2020-12-22 2022-06-30 三洋電機株式会社 Hermetically sealed battery
WO2024162017A1 (en) * 2023-01-31 2024-08-08 パナソニックＩｐマネジメント株式会社 Power storage device
WO2025134690A1 (en) * 2023-12-21 2025-06-26 パナソニックＩｐマネジメント株式会社 Non-aqueous electrolyte secondary battery

Similar Documents

Publication Publication Date Title
WO2014017091A1 (en) Secondary battery
JP6033876B2 (en) Secondary battery gasket and secondary battery
JP7320491B2 (en) battery
CN112368878B (en) Secondary battery
US10256456B2 (en) Rectangular secondary battery and method of making the same
WO2021153439A1 (en) Power storage device
JP6102688B2 (en) Power storage device
CN106920903B (en) Secondary battery
JP5867376B2 (en) Sealed battery
JP6683150B2 (en) Cylindrical battery
US10340502B2 (en) Secondary battery and manufacturing method of secondary battery
JP5673195B2 (en) battery
WO2023100768A1 (en) Power storage device
JP2014123661A (en) High-voltage capacitor
JP7081771B2 (en) Cylindrical rechargeable battery containing a grooved gasket
WO2021200439A1 (en) Cylindrical battery
JP6135557B2 (en) Power storage device
JP2009181782A (en) Closed battery
JP2015230795A (en) Secondary battery
JP6281423B2 (en) Power storage device
CN105609697A (en) Terminal component and method of manufacturing terminal component
JP6456802B2 (en) Current interrupt device and power storage device using the same
WO2023167010A1 (en) Cylindrical battery
JP6498556B2 (en) Current interrupt device and power storage device using the same
JP6520304B2 (en) Power storage device

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 13822104

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 13822104

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: JP