JP2015099735A - Power storage device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power storage device capable of suppressing a fracture part of a current cutoff device from being damaged due to opening or closing of a lid part of a case during assembly manufacturing.SOLUTION: A power storage device 100 according to an embodiment comprises: an electrode assembly 60 laminated with a plurality of sheet-like negative and positive electrodes each of which includes collector parts 67 and 65; a case 1 with a body part 62 housing the electrode assembly 60 and a lid part 63; a positive electrode terminal 119 and a negative electrode terminal 19 provided in the lid part 63; and a current cutoff device 2 including an energizing path and provided between the collector part 67 of the negative electrode and the negative electrode terminal 19. The collector part 67 of the negative electrode and the collector part 65 of the positive electrode are aggregated to one end in a lamination direction of the electrode assembly 60. The collector part 67 of the negative electrode is electrically connected to the negative electrode terminal 19, and the collector part 65 of the positive electrode is electrically connected to the positive electrode terminal 119. The current cutoff device 2 is bonded to the electrode assembly 60 via a buffer member 30 having an adhesive surface.

Description

  The present invention relates to a power storage device having a current interruption function.

  As power storage devices, secondary batteries such as lithium ion batteries, electric double layer capacitors, and the like are known. Patent Documents 1 to 3 disclose this type of power storage device. In these power storage devices, an electrode assembly and an electrolytic solution are accommodated in a sealed case, and electrode terminals (a positive electrode terminal and a negative electrode terminal) are provided in the case.

  By the way, in a power storage device, a charging current larger than usual flows due to some abnormality during charging, and as a result, an overcharged state occurs, and gas may be generated in the case. In this case, in the sealed power storage device, the pressure inside the case may increase and the case may be damaged.

  Regarding this problem, the power storage devices disclosed in Patent Documents 1 to 3 include a current interrupt device (CID). This current interrupt device has an energization path, is provided between the electrode terminal and the electrode assembly, connects the electrode terminal and the electrode assembly in series via the energization path, and the pressure inside the case is abnormal. When the current rises, the current path is physically broken.

International Publication No. 2013/154166 JP 2010-212034 A Japanese Patent No. 5147206

  By the way, as a case of a power storage device, there is a case in which a bottomed cylindrical main body portion that accommodates an electrode assembly and a lid portion that covers an opening of the main body portion are provided, and an electrode terminal is provided on the lid portion. Further, as an electrode assembly of a power storage device, there is a stacked electrode assembly in which a plurality of sheet-like positive electrodes and a plurality of negative electrodes each having a current collector are alternately stacked via separators. When using these cases and the electrode assembly, the plurality of positive electrode current collectors and the plurality of negative electrode current collectors of the electrode assembly housed in the main body are disposed at one end of the electrode assembly in the stacking direction. They may be aggregated and connected to electrode terminals provided on the lid. In this case, the current interrupting device is provided between the electrode terminal and the current collector, that is, on the lid side of the case.

  In this power storage device, the lid portion may be opened and closed with a current interrupting device with the current collecting portion as a fulcrum before the sealing process for sealing the main body portion and the lid portion of the case at the time of assembly and manufacturing. There is a possibility that the broken portion of the current interrupting device may be damaged due to vibration or impact.

  Therefore, an object of the present invention is to provide a power storage device that can prevent the breakage portion of the current interrupting device from being damaged due to the opening and closing of the lid portion of the case during assembly manufacturing.

  The power storage device of the present invention includes (1) an electrode assembly in which a plurality of sheet-like negative electrodes and positive electrodes each having a current collector are alternately stacked via separators, and (2) a bottomed cylindrical shape that accommodates the electrode assembly A case having a main body portion and a lid portion covering the opening of the main body portion, (3) a positive electrode terminal and a negative electrode terminal provided on the lid portion, and (4) a current collecting path, Between the positive electrode terminal and at least one of the negative electrode current collector and the negative electrode terminal, the positive electrode current collector or the negative electrode current collector and the positive electrode terminal or the negative electrode terminal are connected via an energization path. And a current interrupting device that interrupts an energization path when the internal pressure in the case rises, and (5) a plurality of negative current collectors and a plurality of positive current collectors Are each integrated at one end in the stacking direction of the electrode assembly, and the negative electrode terminal and the positive electrode Each is electrically connected to the child, (6) the current interrupting device, the electrode assembly, characterized in that it is bonded via a cushioning member having an adhesive surface.

  According to this power storage device, since the current interrupt device is joined to the electrode assembly via the buffer member having the adhesive surface, the current interrupt device and the electrode assembly are relatively fixed by the buffer member. . Therefore, according to this power storage device, even before the sealing step for sealing the main body and the lid of the case at the time of assembly and manufacturing, the current interruption is performed with the current collector of the negative electrode and the current collector of the positive electrode as fulcrums. It can suppress that a cover part opens and closes with an apparatus, and can suppress that the fracture | rupture part of an electric current interruption apparatus is damaged.

  The positive electrode terminal or the negative electrode terminal described above may be joined to the electrode assembly via a buffer member having an adhesive surface.

  According to this, since the positive electrode terminal or the negative electrode terminal is joined to the electrode assembly via the buffer member having the adhesive surface, the positive electrode terminal or the negative electrode terminal and the electrode assembly are relatively fixed by the buffer member. Is done. Accordingly, even before the sealing step for sealing the case main body and the lid at the time of assembly and manufacturing, the lid with the positive electrode terminal and the negative electrode terminal is used as a fulcrum with the current collector of the negative electrode and the current collector of the positive electrode as fulcrums. It is possible to suppress the opening and closing of the portion, and it is possible to suppress damage to relatively fragile portions such as welded portions in the positive electrode terminal and the negative electrode terminal.

  Moreover, the above-described buffer member may be a sponge-like member made of urethane. Here, in the case where the power storage device is installed so that the case lid portion is always positioned vertically upward, the upper end side of the electrode assembly may not be immersed in the electrolyte. In this regard, according to this, since the buffer member located above the electrode assembly is sponge-like, the electrolyte solution can be absorbed and held, and the held electrolyte solution can be held at the upper end side of the electrode assembly. Can be supplied to.

  ADVANTAGE OF THE INVENTION According to this invention, it can suppress that the fracture | rupture part of an electric current interruption apparatus originates in opening / closing of the cover part of a case at the time of assembly manufacture.

It is sectional drawing of the electrical storage apparatus which concerns on one Embodiment of this invention. It is a disassembled perspective view of the electrical storage apparatus which concerns on one Embodiment of this invention. FIG. 3 is a diagram showing the current interrupting device shown in FIGS. 1 and 2 in a normal state. It is a current interrupting device shown in Drawing 1 and Drawing 2, and is a figure showing an electric current interrupting device in the state where an energization course was broken.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals.

  FIG. 1 is a cross-sectional view of a power storage device according to an embodiment of the present invention, and FIG. 2 is an exploded perspective view of the power storage device according to an embodiment of the present invention. The power storage device 100 shown in FIGS. 1 and 2 is a nonaqueous electrolyte secondary battery such as a lithium ion secondary battery, for example. The power storage device 100 includes a case 1, an electrode assembly 60, a negative terminal (electrode terminal) 19, a positive terminal (electrode terminal) 119, a current interrupt device 2, and buffer members 30 and 31. .

  The case 1 has a bottomed cylindrical main body 62 that houses the electrode assembly 60, and a lid 63 that closes the opening of the main body 62. More specifically, the main body portion 62 has a rectangular box shape, and the lid portion 63 has a rectangular flat plate shape. The main body 62 and the lid 63 are made of a metal such as stainless steel or aluminum, for example. In the following description, the main body 62 and the lid 63 may be simply referred to as the case 1. The case 1 contains an electrode assembly 60 and is filled with, for example, an organic solvent-based or non-aqueous electrolyte. An insulating sheet 61 is provided on the inner surface of the case 1. The lid 63 of the case 1 is provided with a negative electrode terminal 19 and a positive electrode terminal 119. The case 1 is a sealed container by welding the main body 62 and the lid 63.

  The electrode assembly 60 includes a plurality of sheet-like positive electrodes (electrodes), a plurality of sheet-like negative electrodes (electrodes), and a plurality of sheet-like separators arranged between the positive and negative electrodes. The electrode assembly 60 is a stacked electrode assembly in which a plurality of positive electrodes and a plurality of negative electrodes are alternately stacked via separators.

  The positive electrode has, for example, a metal foil made of an aluminum foil and a positive electrode active material layer formed on both surfaces of the metal foil. The positive electrode active material layer is formed including a positive electrode active material and a binder. Examples of the positive electrode active material include composite oxide, metallic lithium, and sulfur. The composite oxide includes, for example, at least one of manganese, nickel, cobalt, and aluminum and lithium.

  A positive electrode current collector 65 is formed at the upper edge of the positive electrode (the edge of the positive electrode on the opening side of the main body 62). The positive electrode current collector 65 extends to one end in the stacking direction of the electrode assembly 60 and is aggregated, and is electrically connected to the positive electrode terminal 119. In the present embodiment, the positive electrode current collector 65 and the positive electrode terminal 119 are indirectly connected by a positive electrode lead (conductive member) 64. The positive electrode current collector 65 and the positive electrode lead 64, and the positive electrode lead 64 and the positive electrode terminal 119 are joined by welding, for example.

  On the other hand, the negative electrode has, for example, a metal foil made of copper foil and a negative electrode active material layer formed on both surfaces of the metal foil. The negative electrode active material layer is formed including a negative electrode active material and a binder. Examples of the negative electrode active material include carbon such as graphite, highly oriented graphite, mesocarbon microbeads, hard carbon, and soft carbon, alkali metals such as lithium and sodium, metal compounds, SiOx (0.5 ≦ x ≦ 1.5 ) And the like, and boron-added carbon.

  A negative electrode current collector 67 is formed at the upper edge of the negative electrode (the edge of the negative electrode on the opening side of the main body 62). The negative electrode current collector 67 extends to one end in the stacking direction of the electrode assembly 60 and is aggregated and electrically connected to the negative electrode terminal 19. In the present embodiment, a negative electrode lead (conductive member) 68 is electrically connected to the negative electrode current collector 67. In addition, a current interrupt device 2 is provided below the negative terminal 19. The current interruption device 2 is provided between the negative electrode terminal 19 and the negative electrode lead 68, and the negative electrode terminal 19 and the negative electrode lead 68 are electrically connected in series via the current interruption device 2. That is, the negative electrode terminal 19 and the negative electrode current collector 67 are indirectly and electrically connected in series via the negative electrode lead 68 and the current interrupt device 2. The negative electrode current collector 67 and the negative electrode lead 68, and the negative electrode lead 68 and the current interrupt device 2 are joined together by welding, for example.

  In addition, as a material of a separator, the porous film which consists of polyolefin resin, such as polyethylene (PE) and a polypropylene (PP), the woven fabric or nonwoven fabric which consists of a polypropylene, a polyethylene terephthalate (PET), methylcellulose, etc. are illustrated.

  Further, the negative electrode terminal 19 and the lid portion 63 of the case 1 and the positive electrode terminal 119 and the lid portion 63 of the case 1 are insulated by an insulating sheet or the like. Further, the negative electrode lead 68 and the positive electrode lead 64 are insulated from the case 1 by an insulating sheet 66 attached to the lid portion 63 of the case 1.

  Next, the current interrupting device 2 will be described with reference to FIGS. 3 and 4. 3 and 4, the illustration of the electrode assembly 60 (see FIG. 1) including the positive electrode and the negative electrode is omitted. The electrode assembly 60 is disposed below FIGS. 3 and 4, the buffer members 30 and 31 are not shown. The buffer member 30 is disposed below the current interrupt device 2, and the buffer member 31 is disposed below the positive terminal 119. 3 and 4, the illustration of the insulating sheet 66 interposed between the negative electrode terminal 19 and the case 1 is omitted.

  As described above, the current interrupt device 2 is provided between the negative electrode terminal 19 and the negative electrode lead 68 (that is, the negative electrode current collector 67). The current interrupting device 2 has an energization path 21 to be described later, and the negative electrode terminal 19 and the negative electrode lead 68 (that is, the negative electrode current collector 67) are connected in series via the energization path 21. As described above, the current interrupt device 2 electrically connects the electrode assembly 60 and the negative electrode terminal 19. When the internal pressure in the case 1 rises above a predetermined level, the current interrupt device 2 interrupts the energization between the electrode assembly 60 and the negative electrode terminal 19 by interrupting the energization path 21.

  The above-mentioned “predetermined level of internal pressure” means that the power storage device 100 is overcharged (overvoltage) or the power storage device 100 is overheated (thermal runaway temperature of the active material). It means internal pressure. The “predetermined level of internal pressure” is set according to conditions such as the capacity of the power storage device 100 and the output voltage. In the power storage device 100, the current interrupt device 2 is arranged below the negative electrode terminal 19. However, the position where the current interrupting device 2 is disposed is not limited to the position below the negative electrode terminal 19. The current interrupt device 2 may be arranged at any position as long as the electrode assembly 60 and the negative electrode terminal 19 can be electrically connected in series via the current interrupt device 2.

  The current interrupt device 2 is disposed inside the case 1 of the power storage device 100 and is sealed so that the gas inside the case 1 (outside the current interrupt device 2) does not flow inside the current interrupt device 2. The structure of the current interrupt device 2 will be described in order from the inside of the case 1 of the power storage device 100 (downward in FIG. 3) to the outside of the case 1 (upward in FIG. 3). The current interrupt device 2 includes a deformation plate 3 having a pressure receiving portion 22, a current supply plate 4, a contact plate 5, a sealing lid body 7, a protrusion 12, a support member 11, and a crimping member 20. .

  The deformable plate 3 is formed of a thin plate and is formed so that the central portion protrudes. An example of the deformable plate 3 is a metallic diaphragm. The deformable plate 3 is disposed so that the center portion protrudes downward (on the electrode assembly 60 side), and the outer peripheral portion is fixed to the insulating support member 11. A seal member 14 is provided on the outer peripheral portion of the surface of the deformable plate 3 opposite to the surface on the electrode assembly 60 side (a surface on the side of the energizing plate 4 described later), and an insulating protrusion 12 is provided in the central portion. Is provided. The shape of the protrusion 12 is, for example, a cylindrical shape. At least a part of the deformable plate 3 is exposed in the case 1 so as to be deformed when the internal pressure in the case 1 increases. That is, the deformation plate 3 is disposed on the outer portion of the current interrupt device 2 and forms the outer surface of the current interrupt device 2.

  The energization plate 4 is formed in a plate shape with a conductive member, and is electrically connected to the negative electrode lead 68 of the electrode assembly 60. In the present embodiment, the current-carrying plate 4 is formed such that the central part is thinner than the other parts of the current-carrying plate 4. Specifically, a depression is provided in the center of the energization plate 4.

  The energizing plate 4 is provided on the seal member 14 on the deformable plate 3 so that the central portion faces the protrusion 12 and is spaced apart from the deformable plate 3 by a predetermined distance. The “predetermined interval” is an interval at which the central portion of the energization plate 4 is not destroyed by vibration when mounted on an automobile, for example. The outer peripheral portion of the energization plate 4 is fixed to the insulating support member 11 and a seal member 17 is provided on the surface opposite to the surface on the deformation plate 3 side. A breaking groove 16 is provided in the central portion of the energizing plate 4 around a portion that comes into contact with the protrusion 12 when the internal pressure in the case 1 reaches a predetermined level.

  The contact plate 5 is formed of a conductive thin plate and is formed so that the central portion protrudes. An example of the contact plate 5 is a conductive metal diaphragm. The contact plate 5 is disposed on the sealing member 17 on the energizing plate 4 so that the center portion protrudes downward (on the energizing plate 4 side) and comes into contact with the energizing plate 4, and the outer peripheral portion is an insulating support member. 11 is fixed. The contact plate 5 and the current plate 4 may be fixed by welding or the like.

  The conductive sealing lid 7 is provided on the contact plate 5 and is electrically connected to the contact plate 5. The sealing lid body 7 has a female screw portion 8 and is screw-coupled to the male screw portion 9 of the negative electrode terminal 19 fixed to the case 1. The outer periphery of the sealing lid 7 is fixed to an insulating support member 11. Note that at least a part of the upper surface of the sealing lid 7 protrudes into the case 1, and a sealing member 10 is mounted between the upper surface of the sealing lid 7 and the inner surface of the case 1. The sealing lid 7 and the case 1 are electrically insulated by a seal member 10.

  A recess 18 that is recessed upward (on the side away from the contact plate 5) is provided on the surface of the sealing lid 7 that faces the central portion of the contact plate 5. More specifically, the central portion of the sealing lid body 7 is recessed above the outer peripheral portion of the sealing lid body 7 (the portion in contact with the contact plate 5). The recess 18 is a space for deforming the contact plate 5 upward.

  The support member 11 has an insulating property, and is formed by, for example, a resin mold. When the support member 11 is viewed in plan, it has a ring shape. The cross section of the support member 11 is substantially U-shaped. The substantially U-shaped portion is provided with the outer peripheral portion of the deformable plate 3, the seal member 14, the outer peripheral portion of the energizing plate 4, the insulating seal member 17, the contact plate 5, and the outer peripheral portion of the sealing lid 7. The deformable plate 3, the seal member 14, the energizing plate 4, the seal member 17, the contact plate 5 and the sealing lid body 7 are integrated. The outer surface of the support member 11 is covered with a metal caulking member 20. The caulking member 20 reliably holds the member provided in the substantially U-shaped part. Further, the inside of the current interrupt device 2 is sealed by the crimping member 20. That is, the deformation plate 3, the seal member 14, the energization plate 4, the seal member 17, and the contact plate 5 are disposed in the current interrupt device 2.

  The energization path will be described. The arrow indicates the energization path 21 from the electrode assembly 60 to the negative electrode terminal 19. As described above, the current-carrying plate 4 is electrically connected to the electrode assembly 60 (see FIG. 1) disposed inside the case 1. Further, the central portion of the energization plate 4 is electrically connected to the contact plate 5, and the outer peripheral portion of the contact plate 5 is electrically connected to the sealing lid 7. Thereby, a series energization path 21 from the electrode assembly 60 to the negative electrode terminal 19 is formed.

  For example, when the power storage device 100 is overcharged, gas is generated inside the sealed case 1 and the internal pressure of the case 1 increases. In this case, as shown in FIG. 4, the internal pressure of the case 1 acts on the deformation plate 3, and the deformation plate 3 is deformed (reversed) upward (on the current-carrying plate 4 side). When the deformable plate 3 is deformed upward, the protrusion 12 collides with the energizing plate 4, the energizing plate 4 is broken starting from the breaking groove 16, and a part of the energizing plate 4 is separated. Then, a part separated from the energizing plate 4 comes into contact with the central portion of the contact plate 5, and the central portion of the contact plate 5 is deformed (reversed) upward (on the negative electrode terminal 19 side). As a result, the energization path 21 is broken and the current is interrupted. That is, conduction between the negative electrode terminal 19 and the electrode assembly 60 is interrupted. In other words, the current flow of the power storage device 100 is interrupted.

  After the energization path 21 is broken, the projection 12 keeps a part separated from the energization plate 4 in a state of being separated from the energization plate 4, thereby preventing the energization path 21 from being formed again. In addition, the deformation | transformation board 3 is not contacting other components other than the outer peripheral part being fixed to the supporting member 11. FIG. Therefore, the deformable plate 3 operates stably by the internal pressure of the case 1. Further, when the protrusion 12 provided on the deformable plate 3 hits the energizing plate 4, an impact force is applied to the energizing plate 4.

  In the above embodiment, the example in which the insulating protrusion 12 protruding toward the contact plate 5 side is provided in the central portion of the insulating deformation plate 3 has been described. In this case, the sealing member 14 may not have insulation. On the other hand, when the seal member 14 is formed of an insulating material (for example, rubber), the deformable plate 3 and the protrusion 12 may be formed of a conductive material such as metal. Further, instead of providing the insulating protrusion 12 at the center of the deformable plate 3, the entire deformable plate 3 may be formed of an insulating material. Or you may form only the part which contacts the contact plate 5 and the electricity supply board 4 of the processus | protrusion 12 with an insulating material. Alternatively, an insulating coating may be applied to the protrusion 12.

  What is important is that when the internal pressure of the case 1 rises and the deformable plate 3 is deformed upward, an impact is applied to the energizing plate 4 and a part of the energizing plate 4 is separated from the energizing plate 4, and the energizing path This is to maintain a state where a part separated from the current-carrying plate 4 and the current-carrying plate 4 are electrically insulated after 21 is broken.

  The buffer members 30 and 31 will be described with reference to FIGS. 1 and 2 again. The buffer member 30 is provided below the current interrupt device 2, that is, between the current interrupt device 2 and the electrode assembly 60. On the other hand, the buffer member 31 is provided below the positive electrode terminal 119, that is, between the positive electrode terminal 119 and the electrode assembly 60.

  The buffer members 30 and 31 are sponge-like members made of, for example, urethane. In the buffer member 30, two opposing surfaces have adhesiveness, one surface is bonded to the current interrupt device 2, and the other surface is bonded to the electrode assembly 60. Thus, the electric current interruption apparatus 2 will be joined to the electrode assembly 60 via the buffer member 30 which has an adhesion surface. Similarly, in the buffer member 31, two opposing surfaces have adhesiveness, one surface is bonded to the positive electrode terminal 119, and the other surface is bonded to the electrode assembly 60. In this way, the positive electrode terminal 119 is joined to the electrode assembly 60 via the buffer member 31 having an adhesive surface.

  Here, in the power storage device 100 of the present embodiment, when the buffer members 30 and 31 are not provided, the positive electrode current collector 65 before the can sealing process for sealing the main body 62 and the lid 63 of the case 1 during assembly and manufacturing. And the negative current collector 67 as a fulcrum, the lid 63 may open and close together with the current interrupt device 2 and the positive terminal 119, and the break portion of the current interrupt device 2 is broken due to vibration and impact at that time. (In the present embodiment, there is a possibility that a part of the current-carrying plate 4 is separated).

  In this regard, in the power storage device 100 of the present embodiment, the current interrupt device 2 is joined to the electrode assembly 60 via the buffer member 30 having an adhesive surface. The electrode assembly 60 is relatively fixed. Further, in the power storage device 100 of the present embodiment, the positive electrode terminal 119 is joined to the electrode assembly 60 via the buffer member 31 having an adhesive surface, so that the positive electrode terminal 119 and the electrode assembly 60 are joined by the buffer member 31. And are relatively fixed. Therefore, according to the power storage device 100 of the present embodiment, the positive electrode current collector 65 and the negative electrode current collector are formed even before the sealing step for sealing the main body 62 and the lid 63 of the case 1 during assembly and manufacture. 67, the lid 63 can be prevented from opening and closing with the current interrupt device 2 and the positive terminal 119, and the breakage of the current interrupt device 2 can be prevented from being broken (broken). At the same time, it is possible to suppress damage to relatively weak parts such as a welded part in the positive electrode terminal 119.

  In addition, according to the power storage device 100 of the present embodiment, the electrode assembly 60 is connected to the current interrupting device 2 and the positive electrode terminal after assembly and manufacturing, that is, after the sealing step of sealing the main body 62 and the lid 63 of the case 1. By being fixed to 119, physical interference between the electrode assembly and the case 1 due to external vibration and impact can be reduced.

  Here, when the power storage device 100 is installed so that the lid portion 63 of the case 1 is always positioned above the vertical direction, the upper end side of the electrode assembly 60 may not be immersed in the electrolytic solution.

  In this regard, according to the power storage device 100 of the present embodiment, since the buffer members 30 and 31 located above the electrode assembly 60 are sponge-like, they can absorb and hold the electrolytic solution. The electrolyte can be supplied to the upper end side of the electrode assembly 60.

  The present invention is not limited to the above-described embodiment, and various modifications can be made. For example, in the present embodiment, the mode in which the current interrupting device is electrically connected to the negative terminal is illustrated, but the current interrupting device may be electrically connected to the positive terminal. That is, the current interrupt device may be provided between any one of the negative electrode terminal and the negative electrode current collector and between the positive electrode terminal and the positive electrode current collector, or may be provided on both. Good.

  Moreover, although the positive electrode current collection part illustrated the form joined indirectly to a positive electrode terminal via a positive electrode lead in this embodiment, the positive electrode current collection part may be directly joined to the positive electrode terminal. . Similarly, in the present embodiment, the mode in which the negative electrode current collector is indirectly joined to the negative electrode terminal via the negative electrode lead and the current interrupt device is illustrated, but the negative electrode current collector is only connected to the negative electrode terminal in the current interrupt device. It may be joined indirectly via.

  In the present embodiment, the power storage module including the secondary battery is illustrated as the power storage device. However, the features of the present invention can be applied to a power storage module including various power storage devices such as an electric double layer capacitor.

  DESCRIPTION OF SYMBOLS 100 ... Power storage device, 1 ... Case, 2 ... Current interruption device, 3 ... Deformation plate, 4 ... Current supply plate, 5 ... Contact plate, 7 ... Sealing lid, 8 ... Female screw part of sealing lid, 9 ... Negative electrode terminal Male screw part, 10, 14, 17 ... sealing member, 11 ... support member, 12 ... projection, 16 ... breaking groove, 18 ... recess of sealing lid, 19 ... negative electrode terminal (electrode terminal), 20 ... caulking member, DESCRIPTION OF SYMBOLS 21 ... Current-carrying path, 22 ... Pressure receiving part, 30, 31 ... Buffer member, 60 ... Electrode assembly, 61, 66 ... Insulating sheet, 62 ... Main part of case, 63 ... Cover part of case, 64 ... Positive electrode lead (conductive) Members), 65... Positive electrode current collector, 67... Negative electrode current collector, 68... Negative electrode lead (conductive member), 119.

Claims (3)

An electrode assembly in which a plurality of sheet-like negative electrodes and positive electrodes having current collectors are alternately stacked via separators;
A case provided with a bottomed cylindrical main body that houses the electrode assembly and a lid that covers the opening of the main body;
A positive electrode terminal and a negative electrode terminal provided on the lid,
A current-carrying path, provided between at least one of the current collector of the positive electrode and the positive electrode terminal, and between the current collector of the negative electrode and the negative electrode terminal, and the current collector of the positive electrode or the negative electrode Current collector and the positive electrode terminal or the negative electrode terminal connected in series via the energization path and a current interrupt device that interrupts the energization path when the internal pressure in the case increases,
A power storage device having
The current collectors of the plurality of negative electrodes and the current collectors of the plurality of positive electrodes are each integrated at one end in the stacking direction of the electrode assembly and electrically connected to the negative electrode terminal and the positive electrode terminal, respectively. And
The power storage device, wherein the current interrupt device is joined to the electrode assembly through a buffer member having an adhesive surface.   The power storage device according to claim 1, wherein the positive electrode terminal or the negative electrode terminal is joined to the electrode assembly through a buffer member having an adhesive surface.   The power storage device according to claim 1, wherein the buffer member is a sponge-like member made of urethane.

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