JP2017022113A - Power storage device - Google Patents

Abstract

A holder and a current-carrying plate are firmly fixed without restricting a current-carrying path while having a simple structure.
A current interrupting device of a power storage device includes an energizing plate, a first deforming plate, and an insulating holder. The holder 80 has a plurality of bosses 76 that are arranged at intervals along the outer peripheral edge of the energizing plate 20 and project toward the energizing plate 20 side. The plurality of bosses 76 have a base portion 76a that extends along the outer surface of the current-carrying plate 20, and a tip portion 76b that is bent from the base portion 76a and extends along the surface opposite to the holder of the current-carrying plate 20.
[Selection] Figure 2

Description

  The technology disclosed in this specification relates to a power storage device.

  The power storage device disclosed in Patent Document 1 includes a current interrupt device that interrupts the energization path when the pressure in the case increases. The current interrupting device includes a current collector that is electrically connected to a power generation element in a case, a pressure-sensitive member that electrically connects the current collector and the electrode terminal, and a holder that supports the current collector. Have. When the pressure in the case increases, the pressure-sensitive member is deformed and disconnected from the current collector, and the electrical connection between the electrode terminal and the power generation element is interrupted. In this power storage device, a plurality of through holes are formed in the outer peripheral portion of the current collector. The holder has a plurality of bosses corresponding to the positions of the plurality of through holes of the current collector. When fixing the current collector to the holder, first, the plurality of bosses of the holder are inserted into the through holes of the current collector, and then the tip of the boss penetrating the current collector is subjected to a heat caulking process. As a result, the current collector is fixed to the holder.

JP 2013-225500 A

  In the power storage device of Patent Document 1, since the current collector is fixed to the holder by thermal caulking processing, a member for fixing the current collector to the holder becomes unnecessary, and the configuration can be simplified. However, in the power storage device of Patent Document 1, a through hole for inserting a boss formed in the holder must be formed in the current collector. Since the current collector serves as an energization path, enlarging the cross-sectional area of the through hole formed in the current collector restricts the energization path of the current collector. For this reason, when the cross-sectional area of the through hole cannot be increased, the fixing strength between the holder and the current collector may not be sufficiently obtained. The present specification discloses a power storage device that can firmly fix a holder and a current collector without limiting an energization path while having a simple structure.

  A first power storage device disclosed in this specification includes an electrode assembly accommodated in a case, an electrode terminal provided in the case, and accommodated in the case, and the electrode assembly and the electrode terminal are electrically connected to each other. And a current interrupting device that switches between a non-conducting state in which the electrode assembly and the electrode terminal are electrically disconnected. The current interrupting device is disposed between the energizing plate electrically connected to the electrode assembly, the first deforming plate electrically connected to the electrode terminal, the energizing plate and the case, and supports the energizing plate. And a sex holder. The first deforming plate is in contact with and electrically connected to the current-carrying plate in the conductive state, while being separated from the current-carrying plate and electrically disconnected from the current-carrying plate in the non-conductive state. The holder has a plurality of bosses arranged at intervals along the outer peripheral edge of the energizing plate and projecting toward the energizing plate side, and the plurality of bosses extend along the outer surface of the energizing plate. And a distal end portion that is bent from the base portion and extends along a surface opposite to the holder of the energization plate. And the electricity supply board is supported by the holder by being pinched | interposed by the surface at the side of the electricity supply plate of a holder, and the front-end | tip part of a some boss | hub. Here, the surface opposite to the holder means a surface opposite to the surface on the holder side (surface farther from the holder than the surface on the holder side).

  In the first power storage device, a plurality of bosses are formed along the outer peripheral edge of the energization plate, and the energization plates are held by bending the tip portions of the plurality of bosses along the energization plate. Since this power storage device is configured to hold the current-carrying plate from the outer peripheral side, there is no need to form a through hole for inserting the boss into the current-carrying plate. Therefore, it is possible to firmly fix the holder and the energizing plate without restricting the energizing path of the energizing plate.

  A second power storage device disclosed in this specification includes an electrode assembly housed in a case, an electrode terminal provided in the case, and housed in the case, and the electrode assembly and the electrode terminal are electrically connected. And a current interrupting device that switches between a non-conducting state in which the electrode assembly and the electrode terminal are electrically disconnected. The current interrupting device is disposed between the energizing plate electrically connected to the electrode assembly, the first deforming plate electrically connected to the electrode terminal, the energizing plate and the case, and supports the energizing plate. And a sex holder. The first deforming plate is in contact with and electrically connected to the current-carrying plate in the conductive state, while being separated from the current-carrying plate and electrically disconnected from the current-carrying plate in the non-conductive state. The holder has an extending portion that is disposed along the outer peripheral edge of the energization plate and protrudes toward the energization plate. The extending portion has a base portion that extends along the outer surface of the energizing plate and a tip portion that is bent from the base portion and extends along a surface opposite to the holder of the energizing plate. And the electricity supply board is supported by the holder by being pinched | interposed by the surface at the side of the electricity supply plate of a holder, and the front-end | tip part of an extending | stretching part.

  In said 2nd electrical storage apparatus, the extending | stretching part is formed along the outer periphery of an electricity supply board, and an electricity supply plate is hold | maintained by bending the front-end | tip part of an extending | stretching part along an electricity supply plate. For this reason, it is not necessary to form the through-hole for inserting a boss | hub in an electricity supply board. Therefore, similarly to the first power storage device, the holder and the energizing plate can be firmly fixed without restricting the energizing path of the energizing plate.

1 is a cross-sectional view of a power storage device according to a first embodiment. The enlarged view of the broken-line part 200a of FIG. 1 (The state after bending the front-end | tip of a boss | hub). The enlarged view of the broken-line part 200a of FIG. 1 (state before bending the front-end | tip of a boss | hub). FIG. 3 is a bottom perspective view schematically showing a holder and a current-carrying plate of the current interrupt device of Example 1 (a state before the tip of the boss is bent). The bottom perspective view which shows typically the holder and energization board of the current interrupting device of Example 2 (state after bending an extension part). The bottom perspective view which shows typically the holder of the electric current interruption apparatus of Example 2, and an electricity supply board (state before bending an extending | stretching part). The principal part enlarged view of the electrical storage apparatus of Example 3 (equivalent to the broken line part 200a of FIG. 1). The bottom view which shows the relative positional relationship of the holder and case of the electric current interruption apparatus of Example 2. FIG.

  The main features of the embodiments described below are listed. Note that the technical elements described below are independent technical elements and exhibit technical usefulness alone or in various combinations, and are not limited to the combinations in the claims at the time of filing. .

(Characteristic 1) In the power storage device disclosed in the present specification, the tip portions of the plurality of bosses may be bent toward the center of the current-carrying plate by a heat caulking process. According to such a structure, the process which bends the front-end | tip part of a boss | hub can be performed simply.

(Characteristic 2) In the power storage device disclosed in the present specification, the distal end portion of the extending portion may be bent toward the center of the current-carrying plate by the heat caulking process. According to such a structure, the process which bends the front-end | tip part of an extending | stretching part can be performed simply.

(Characteristic 3) In the power storage device disclosed in the present specification, the current interrupting device is disposed on the side opposite to the first deformation plate with respect to the energization plate and protrudes toward the central portion of the energization plate. You may further provide the 2nd deformation board in which the processus | protrusion was provided. The second deformable plate has a first state in which the protrusion is located at the first position and the energizing plate and the first deformable plate are in contact with each other when the electrode assembly and the electrode terminal are electrically connected, When the assembly and the terminal are non-conducting, the projection may be switched from the first position to the second position on the current-carrying plate side to be switched to the second state in which the current-carrying plate and the first deformation plate are separated.

  Hereinafter, the power storage device 100 according to the first embodiment will be described. As shown in FIG. 1, the power storage device 100 includes a case 1, an electrode assembly 3 accommodated in the case 1, and terminals 5 and 7 as electrode terminals fixed to the case 1. The electrode assembly 3 and the terminals 5 and 7 are electrically connected. The power storage device 100 also includes a current interrupt device 10 disposed between the electrode assembly 3 and the terminal 7. An electrolyte is injected into the case 1, and the electrode assembly 3 is immersed in the electrolyte.

  The case 1 is made of metal and is a substantially rectangular parallelepiped box-shaped member. The case 1 includes a main body 111 and a lid portion 112 fixed to the main body 111. The lid part 112 covers the upper part of the main body 111. Openings 81 and 82 are formed in the lid portion 112 of the case 1. The terminal 5 communicates with the inside and outside of the case 1 through the opening 81, and the terminal 7 communicates with the inside and outside of the case 1 through the opening 82.

  The electrode assembly 3 includes a positive electrode sheet, a negative electrode sheet, and a separator disposed between the positive electrode sheet and the negative electrode sheet. The electrode assembly 3 is configured by laminating a plurality of positive electrode sheets, a plurality of negative electrode sheets, and a plurality of separators. The positive electrode sheet and the negative electrode sheet include a current collecting member and an active material layer formed on the current collecting member. As the current collecting member, one used for the positive electrode sheet is, for example, an aluminum foil, and one used for the negative electrode sheet is, for example, a copper foil. The electrode assembly 3 includes a positive current collecting tab 41 and a negative current collecting tab 42. The positive electrode current collecting tab 41 is formed on the upper end portion of the positive electrode sheet. The negative electrode current collecting tab 42 is formed on the upper end portion of the negative electrode sheet. The positive electrode current collecting tab 41 and the negative electrode current collecting tab 42 protrude above the electrode assembly 3. The positive electrode current collecting tab 41 is fixed to the positive electrode lead 43. The negative electrode current collecting tab 42 is fixed to the negative electrode lead 44.

  The positive electrode lead 43 is connected to the positive electrode current collecting tab 41 and the terminal 5. The positive electrode current collecting tab 41 and the terminal 5 are electrically connected via the positive electrode lead 43. An insulating member 72 is disposed between the positive electrode lead 43 and the case 1. The insulating member 72 insulates the positive electrode lead 43 from the lid portion 112 of the case 1.

  The negative electrode lead 44 is connected to the negative electrode current collecting tab 42 and the connection terminal 46. The connection terminal 46 is electrically connected to the terminal 7 via the current interrupt device 10. Therefore, the negative electrode current collecting tab 42 and the terminal 7 are electrically connected via the negative electrode lead 44, the connection terminal 46, and the current interrupt device 10. Thereby, an energization path for connecting the electrode assembly 3 and the terminal 7 is formed. The current interrupt device 10 can interrupt this energization path. The configuration of the current interrupt device 10 will be described later. An insulating member 73 is disposed between the negative electrode lead 44 and the case 1. The insulating member 73 insulates the negative electrode lead 44 from the case 1.

  Resin gaskets 62 and 63 are disposed on the upper surface of the lid portion 112. The gasket 62 includes a protruding portion 66 that protrudes upward from the lid portion 112 and a flat plate portion 68 that extends along the lid portion 112. The protruding portion 66 is disposed on the center side of the opening portion 81 of the lid portion 112, and the flat plate portion 68 is disposed on the opening portion 81 side of the lid portion 112. External terminals 60 are disposed on the upper surface of the gasket 62 along the shape of the upper surface of the gasket 62. The head of the bolt 64 is disposed in a bottomed hole 62 a formed in the protrusion 66. The shaft portion of the bolt 64 protrudes upward through the opening of the external terminal 60. The terminal 5, the external terminal 60, and the bolt 64 are electrically connected to each other and constitute a positive terminal. The configuration of the gasket 63, the external terminal 61, and the bolt 65 is the same as the configuration of the gasket 62, the external terminal 60, and the bolt 64 described above. The terminal 7, the external terminal 61, and the bolt 65 are electrically connected to each other and constitute a negative terminal.

  Here, the terminal 7 will be described with reference to FIG. As shown in FIG. 2, the terminal 7 is caulked and fixed to the case 1. The terminal 7 includes a cylindrical portion 94, a base portion 95, and a fixing portion 96. The cylindrical portion 94 is inserted into the opening 82. A through hole 97 is formed in the cylindrical portion 94. The base portion 95 is formed in an annular shape. The base portion 95 is fixed to the lower end portion of the cylindrical portion 94. The base portion 95 is disposed inside the case 1. A recess 98 is formed in the base portion 95. The recess 98 communicates with the through hole 97, and the inside of the recess 98 is maintained at atmospheric pressure. The fixed portion 96 is formed in an annular shape and is disposed at the upper end portion of the cylindrical portion 94. The fixing part 96 is disposed outside the case 1. The terminal 7 is fixed to the lid portion 112 of the case 1 by a fixing portion 96. The base portion 95 is formed with a protruding portion 99 (detailed later). The protruding portion 99 is formed in an annular shape along the outer peripheral edge of the lower surface of the base portion 95. The protruding portion 99 protrudes downward (on the side of the energizing plate 20 described later) from the lower surface of the base portion 95.

  Next, the current interrupt device 10 will be described. As shown in FIG. 2, the current interrupt device 10 includes an energization plate 20, a first deformation plate 30, and a holder 80. The first deformation plate 30 is a circular conductive diaphragm, and protrudes downward. The first deformation plate 30 has a central portion 32 and an outer peripheral portion 31. A central portion 32 of the first deformation plate 30 is connected to the energization plate 20. The outer peripheral portion 31 of the first deformation plate 30 is connected to the outer peripheral portion of the lower surface of the base portion 95. Specifically, the outer peripheral portion 31 of the first deformation plate 30 is welded to a region of the lower surface of the base portion 95 where the projecting portion 99 is not formed. When the first deformation plate 30 is connected to the lower surface of the base portion 95, the outer peripheral surface of the first deformation plate 30 comes into contact with the inner wall surface of the protrusion 99. Thereby, the connection position with respect to the base part 95 (namely, terminal 7) of the 1st deformation board 30 can be stabilized. The lower end of the recess 98 of the base portion 95 is covered with the first deformation plate 30. Since the inside of the recess 98 is maintained at atmospheric pressure, atmospheric pressure acts on the upper surface of the first deformation plate 30. The energization plate 20 is a metal member and has electrical conductivity. The energization plate 20 is formed in a rectangular shape in plan view, and is disposed below the first deformation plate 30. A connection terminal 46 is connected to the energization plate 20. The energizing plate 20 has a central portion 22 and an outer peripheral portion 21. The outer peripheral portion 21 is located on the outer peripheral side with respect to a later-described vent hole 20 b in the radial direction of the energization plate 20. A groove portion 20 a is formed on the lower surface of the energization plate 20. The groove portion 20a is formed around the central portion 22, and the energizing plate 20 and the central portion 32 of the first deformation plate 30 are connected inside the groove portion 20a. The mechanical strength of the energizing plate 20 at the position where the groove 20a is formed is lower than the mechanical strength of the energizing plate 20 at a position other than the groove 20a. A vent hole 20 b is formed in the energization plate 20, and a space 50 between the deformation plate 30 and the energization plate 20 communicates with a space in the case 1.

  The holder 80 accommodates and holds the base portion 95 of the terminal 7, the first deformation plate 30, the energization plate 20, and the seal member 75 therein. A through hole 79a is formed at the upper end of the holder 80, and the cylindrical portion 94 of the terminal 7 is inserted into the through hole 79a. The lower end of the holder 80 is released and is closed by the energizing plate 20. The holder 80 is made of an insulating material having elasticity. For the holder 80, for example, polyphenyl sulfide (PPS) is used. The material of the holder 80 is not limited to the above-described PPS, and is a material having insulating properties and electrolytic solution resistance (for example, perfluoroalkoxyalkane (PFA), polytetrafluoroethylene (PTFE), polypropylene (PP), etc.). I just need it.

  The holder 80 has an upper end portion 79, a central portion 78, and a boss 76. The upper end 79 is formed in an annular shape having a through hole 79a at the center thereof. As described above, the cylindrical portion 94 of the terminal 7 is inserted into the through hole 79 a of the upper end portion 79. The upper end portion 79 is disposed between the lower surface of the lid portion 112 of the case 1 and the upper surface of the base portion 95 of the terminal 7. That is, the lower surface of the lid portion 112 is in contact with the upper surface of the upper end portion 79, and the upper surface of the base portion 95 is in contact with the lower surface of the upper end portion 79. The lower surface of the lid portion 112 and the upper surface of the base portion 95 are insulated by the upper end portion 79 of the holder 80.

  The central portion 78 extends downward from the outer peripheral edge of the upper end portion 79. The central portion 78 is formed in an annular shape, and accommodates the base portion 95 and the first deformation plate 30 therein. A first portion that contacts the outer peripheral surface of the base portion 95 and a recess 77 positioned below the first portion are formed on the inner surface of the central portion 78. The first portion is formed on the upper end side of the central portion 78, and the recess 77 is formed on the lower end side of the central portion 78. The diameter of the recess 77 is larger than the diameter of the base portion 95 (the diameter of the first portion). Since the projecting portion 99 is formed on the lower surface of the base portion 95, when the base portion 95 is accommodated in the central portion 78, a part of the projecting portion 99 projects into the recess 77. By projecting the projecting portion 99 into the recess 77, a space for accommodating the seal member 75 is formed in the recess 77. Note that the lower surface of the central portion 78 is in contact with the upper surface of the energizing plate 20.

  The seal member 75 is accommodated in a space outside the protruding portion 99 of the recess 77. The sealing member 75 makes a round in the circumferential direction on the outer peripheral side of the base portion 95 of the terminal 7. The seal member 75 is accommodated in a compressed state in the above-described space, and is in contact with the energizing plate 20, the holder 80, and the protruding portion 99. The seal member 75 seals between the two at each contact portion. As a result, the space inside the case 1 and the space outside the case 1 are sealed. The seal member 75 is an O-ring made of ethylene-propylene rubber (EPM) such as ethylene / propylene / diene rubber (EPDM). The sealing member 75 is not limited to the above, and a material having sealing properties, insulating properties, electrolytic solution resistance, and elasticity may be used.

  Note that the lower end of the projecting portion 99 formed on the lower surface of the base portion 95 is located below the upper end of the recess 77, but is not in contact with the energizing plate 20. Since the seal member 75 abuts against the protruding portion 99, the seal member 75 is prevented from being displaced with respect to the energizing plate 20 and the holder 80.

  As shown in FIGS. 2 to 4, a plurality of bosses 76 are formed on the holder 80. The plurality of bosses 76 are formed at a plurality of locations on the lower surface of the central portion 78. Specifically, when the holder 80 and the current-carrying plate 20 are viewed in plan, the plurality of bosses 76 are formed at regular intervals (for example, four at 90 ° intervals) along the outer peripheral edge of the current-carrying plate 20. ing. For example, when the energizing plate 20 is a square plate, the bosses 76 can be arranged at the four corners of the energizing plate 20. Further, since the boss 76 is bent below the energizing plate 20, the position where the boss 76 is disposed is outside the outer peripheral edge of the energizing plate 20. In FIG. 4 (the same applies to FIGS. 5 and 6 described below), for convenience of explanation, the main body 111 of the case 1 is omitted, but the current is actually cut off from the outer peripheral edge of the lid portion 112 of the case 1. The wall of the main body 111 extends vertically to the apparatus side.

  As shown in FIG. 2, each of the plurality of bosses 76 has a base portion 76a and a tip portion 76b. The base portion 76 a extends downward along the outer surface of the energization plate 20. The distal end portion 76b is bent from the base portion 76a and extends horizontally along the lower surface of the energization plate 20 (the surface on the side opposite to the holder). That is, the holder 80 positions and supports the energizing plate 20 by the base portions 76 a and the tip portions 76 b of the plurality of bosses 76. Specifically, the base portion 76 a of the boss 76 abuts against the outer surface of the energization plate 20, whereby the horizontal position of the energization plate 20 with respect to the holder 80 is positioned. In addition, the energizing plate 20 is supported by the holder 80 by sandwiching the energizing plate 20 between the lower surface of the holder 80 (the lower surface of the central portion 78) and the tip 76b of the boss 76.

  As shown in FIG. 3, the boss 76 extends downward from the lower surface of the holder 80 before the boss 76 is bent. That is, the base portion 76a and the tip portion 76b are arranged on the same straight line. In order to support the energizing plate 20 on the holder 80, the holder 80 and the energizing plate 20 are assembled in a state where the boss 76 is not bent. Thereafter, the current-carrying plate 20 is supported by the holder 80 by bending the tip 76b of the boss 76. A heat caulking process can be used to bend the distal end portion 76b.

  As is clear from the above description, the current interrupt device 10 has an energization path that connects the connection terminal 46, the energization plate 20, the first deformation plate 30, and the terminal 7 in series. For this reason, the electrode assembly 3 and the terminal 7 are electrically connected via the energization path of the current interrupt device 10.

  Here, the interruption | blocking operation | movement of the electric current interruption apparatus 10 is demonstrated. In the above-described power storage device 100, the terminal 5 and the terminal 7 are in a conductive state that can be energized. When the pressure in the case 1 increases due to overcharging of the power storage device 100 or the like, the pressure acting on the lower surface of the first deformation plate 30 increases through the vent hole 20b. On the other hand, atmospheric pressure acts on the upper surface of the first deformation plate 30. For this reason, when the internal pressure of the case 1 rises and reaches a predetermined value, the first deformation plate 30 is reversed and changes to a convex state upward. Then, the energizing plate 20 connected to the central portion 32 of the first deformable plate 30 breaks starting from the mechanically fragile groove portion 20a. As a result, the energization path connecting the energization plate 20 and the first deformation plate 30 is interrupted, and the electrode assembly 3 and the terminal 7 are brought out of electrical conduction. At this time, the first deformation plate 30 is insulated from the connection terminal 46, and the energization plate 20 is insulated from the terminal 7.

  In the power storage device 100 of the first embodiment, a plurality of bosses 76 are formed along the outer peripheral edge of the energization plate 20. The energizing plate 20 is held from the outer peripheral side of the energizing plate 20 by the base portions 76a and the distal end portions 76b of the plurality of bosses 76. Therefore, unlike the prior art, it is not necessary to form a through-hole for inserting the boss 76 in the energizing plate 20, and the energizing path of the energizing plate 20 is not limited. Further, since the number and size of the bosses 76 can be set as appropriate, the force for holding the energizing plate 20 by the holder 80 can be adjusted, and the energizing plate 20 can be firmly fixed to the holder 80.

  Moreover, since it is not necessary to form a through-hole in the electricity supply board 20, compared with a prior art, the shaping | molding of the electricity supply board 20 becomes easy and shaping | molding time can be reduced. Further, the current-carrying plate can be made smaller by the amount of the cross-sectional area of the through-hole that has been conventionally formed, and the material cost can be reduced.

  Next, a power storage device of Example 2 will be described with reference to FIGS. Hereinafter, only differences from the first embodiment will be described, and detailed description of the same configurations as those of the first embodiment will be omitted. The same applies to other embodiments.

  In the power storage device of this embodiment, the configuration of the holder is different from that of the first embodiment. The holder 180 has an upper end portion 179, a central portion 178, and an extending portion 176. The configurations of the upper end portion 179 and the central portion 178 are the same as the upper end portion 79 and the central portion 78 of the holder 80 of the first embodiment.

  The extending portion 176 is formed so as to protrude from the lower surface of the central portion 178. Specifically, the extending portion 176 is formed continuously along the outer peripheral edge of the energizing plate 20 when the holder 180 and the energizing plate 20 are viewed in plan. For example, when the current-carrying plate 20 is a rectangular plate material, as shown in FIG. 5, the extending portions 176 can be arranged along three sides facing the wall surface of the main body 111 of the case 1 of the current-carrying plate 20. In the example shown in FIG. 5, the extending portion 176 extending along each side is connected to the extending portion 176 extending along the adjacent side, and is integrated as a whole. As in the example shown in FIG. 5, the extending portion 176 may extend continuously along the three sides of the current-carrying plate 20 or may extend intermittently along the three sides of the current-carrying plate 20. Good. For example, the extending portion may have a notch formed at the corner of the current-carrying plate 20, and may be formed discontinuously at the corner. Further, since the extending portion 176 is bent below the energizing plate 20, the position where the extending portion 176 is disposed is outside the outer peripheral edge of the energizing plate 20.

  As shown in FIG. 5, the extending portion 176 has a base portion 176a and a tip portion 176b. The base 176a extends downward along the outer surface of the energization plate 20. The distal end portion 176b is bent from the lower end of the base portion 176a and extends horizontally along the lower surface of the energization plate 20 (the surface on the side opposite to the holder). That is, the holder 180 positions the current-carrying plate 20 by the extending portion 176 and supports it on the holder 180.

  As shown in FIG. 6, in a state before the extending portion 176 is bent, the extending portion 176 extends downward from the lower surface of the holder 180. That is, the base 176a and the tip 176b are arranged on the same straight line. In order to make the holder 180 support the current-carrying plate 20, the holder 180 and the current-carrying plate 20 are assembled in a state where the extending portion 176 is not bent. Thereafter, the current-carrying plate 20 is supported by the holder 180 by bending the distal end portion 176b of the extending portion 176. Note that a heat caulking process can be used to bend the tip 176b.

  Also in the power storage device of the second embodiment, since it is not necessary to form a through hole in the current-carrying plate 20, the same effects as the power storage device of the first embodiment can be achieved. Further, in the power storage device of Example 2, the outer surface (three surfaces facing the wall surface of the case 1) of the energization plate 20 is covered with the holder 180. For this reason, it can suppress that the electricity supply board 20 contacts the wall surface of the case 1. FIG. That is, it is possible to suppress a short circuit due to the contact between the energization plate 20 and the case 1.

  Next, a power storage device of Example 3 will be described with reference to FIG. In the power storage device of the present embodiment, the configuration of the current interrupt device is different from that of the first embodiment, and other configurations are the same as those of the first embodiment.

  As illustrated in FIG. 7, the current interrupt device 10 a includes a current-carrying plate 20, a first deformation plate 30, and a metal second deformation plate 40.

  The second deformation plate 40 has a central portion 47 and an outer peripheral portion 48. The second deformation plate 40 is disposed below the energization plate 20, and a central portion 47 projects downward. The upper surface of the outer peripheral part 48 of the 2nd deformation board 40 and the lower surface of the outer peripheral part 21 of the electricity supply board 20 are being fixed by welding. A projecting portion 40 a that projects upward is provided at the center of the upper surface of the second deformable plate 40. A central portion 22 of the energizing plate 20 is located above the protruding portion 40a. The pressure of the space in the case 1 acts on the lower surface of the second deformation plate 40.

  The energization plate 20 is disposed between the second deformation plate 40 and the first deformation plate 30, and the energization plate 20 is formed with a vent hole 20 b. A space 120 between the second deformable plate 40 and the energizing plate 20 communicates with a space 122 between the first deformable plate 30 and the energized plate 20 through the vent hole 20b. The first deformation plate 30 is disposed above the energization plate 20. A space 124 is formed on the upper surface of the first deformation plate 30, and the space 124 is maintained at atmospheric pressure.

  The current interrupt device 10a has an energization path that connects the connection terminal 46, the energization plate 20, the first deformation plate 30, and the terminal 7 in series. For this reason, the electrode assembly 3 and the terminal 7 are electrically connected through the energization path of the current interrupt device 10a.

  Here, the interruption | blocking operation | movement of the electric current interruption apparatus 10a is demonstrated. In the power storage device described above, when the internal pressure of the case 1 increases, the pressure acting on the lower surface of the second deformation plate 40 increases. On the other hand, the pressure of the space 120 sealed from the space in the case 1 acts on the upper surface of the second deformation plate 40. For this reason, if the pressure in case 1 exceeds a predetermined value, the 2nd deformation board 40 will reverse and it will change from a convex state of the lower part to a convex state of the upper part. At this time, the air in the space 120 moves to the space 122 through the vent hole 20b, and the pressure in the space 122 increases. Further, when the second deformable plate 40 changes from the downwardly convex state to the upwardly convex state, the protruding portion 40a of the second deformable plate 40 moves from the first position to the second position, and the central portion of the energizing plate 20 22 and the current-carrying plate 20 is broken at the groove 20a. Thereby, the 1st deformation board 30 reverses and the center part 22 of the 1st deformation board 30 and the electricity supply board 20 displaces upwards. For this reason, the electricity supply path which connects the electricity supply plate 20 and the 1st deformation plate 30 is interrupted | blocked, and it will be in the non-conduction state by which the conduction | electrical_connection between the electrode assembly 3 and the terminal 7 is interrupted | blocked. At this time, the first deformation plate 30 is insulated from the connection terminal 46, and the energization plate 20 is insulated from the terminal 7. Also in the power storage device of the third embodiment, since the configuration of the holder 80 (boss 76) is the same as that of the first embodiment, the same effects as the power storage device 100 of the first embodiment can be achieved. In addition, you may use the electric current interruption apparatus 10a of a present Example for the electrical storage apparatus of Example 2. FIG.

  As mentioned above, although the Example of the technique which this specification discloses was described in detail, these are only illustrations and do not limit a claim. The technology described in the claims includes various modifications and changes of the specific examples illustrated above. For example, in Example 3, the first deformation plate 30 may be formed with a communication hole that connects the space 122 and the space 124, and the spaces 120 and 122 may be maintained at atmospheric pressure.

  Further, the number of the bosses 76 and the area of the front end portion 76b of the boss 76 can be appropriately changed depending on a desired load resistance. The position where the boss 76 is formed can also be set as appropriate, and may be formed at a position along the outer peripheral edge of the energization plate 20.

  Further, the current interrupt device 10 may be provided on the terminal 5 side, or may be provided on both the terminal 5 and the terminal 7. When the current interrupt device 10 is provided on the terminal 5 side, an insulating member can be disposed between the terminal 5 and the lid portion 112 in the same manner as the configuration of the above-described embodiment. Further, in the above embodiment, the first deformation plate 30 is reversed, so that the conduction with the energization plate 20 is interrupted. However, the deformation mode of the first deformation plate 30 is not limited to inversion. For example, when the central portion 32 of the first deformable plate 30 is bent upward, the energizing plate 20 is broken starting from the groove portion 20a, and the conduction between the first deformable plate 30 and the energizing plate 20 is interrupted. Also good. The first deformable plate 30 may be deformed in any way as long as conduction between the first deformable plate 30 and the energizing plate 20 is interrupted. The same applies to the second deformation plate 40.

  As shown in FIG. 8, in the second embodiment, among the inner wall surfaces constituting the main body 111 of the case 1, the inner wall surface 111 a along the first direction (the x direction in FIG. 8) connecting the terminals 5 and 7. The distance L1 between the outer surface 180a of the holder 180 and the inner wall surface 111b along the second direction (y direction in FIG. 8) orthogonal to the first direction among the inner wall surfaces constituting the main body 111 of the case 1 and the holder The distance from the outer surface 180b of 180 may be smaller. In other words, a larger clearance may be secured between the inner wall surface 111 b and the outer surface 180 b of the holder 180 than between the inner wall surface 111 a and the outer surface 180 a of the holder 180. The power storage device may be deformed (depressed) by receiving an impact such as dropping. At this time, if the corner portion of the case (specifically, the contact point between the main body 111 on the negative electrode terminal side and the lid portion 112 in the embodiment) is recessed, an impact is also propagated to the current interrupt device, and the current interrupt device is damaged (for example, May cause a seal failure due to gasket destruction. As apparent from FIG. 8 and the like, the case of the power storage device generally has a shorter width in the y direction than the width in the x direction. For this reason, in particular, when an impact is applied to the corner of the end in the x direction (the corner between the wall surface of the main body 111 extending in the y direction and the lid 112), the corner of the end in the y direction (the main 111 extending in the x direction). Compared with the case where an impact is applied to the corners of the wall surface and the lid portion 112, the external force per unit area generated by the impact is increased, so that the case may be greatly deformed. In the configuration described above, the gap in the x direction is larger than the y direction. That is, L1 <L2, and an appropriate clearance is secured in the x direction. For this reason, even when the case is deformed as described above, it is possible to suppress transmission of the accompanying force to the current interrupt device. Therefore, the current interrupt device can be suitably protected from the external force applied to the power storage device. The above-described configuration may be applied to the first and third embodiments.

  In addition, a plate-like insulating member is disposed between the current breaker (specifically, the current-carrying plate 20 in the first and second embodiments and the second deformation plate 40 in the third embodiment) and the electrode assembly 3. May be. The insulating member may have a size that overlaps the entire range of the current interrupt device in plan view. A material similar to that of the holder 80 can be used for the insulating member. With such a configuration, contact between the current interrupt device and the electrode assembly 3 can be prevented.

  The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology illustrated in the present specification or the drawings achieves a plurality of objects at the same time, and has technical utility by achieving one of the objects.

1: Case 3: Electrode assembly 5, 7: Terminal 10: Current interrupting device 20: Current supply plate 30: First deformation plate 40: Second deformation plate 40a: Protruding portion 41: Positive current collecting tab 42: Negative current collecting tab 43: Positive electrode lead 44: Negative electrode lead 46: Connection terminal 60, 61: External terminal 62, 63: Gasket 64, 65: Bolt 72: Insulating member 73: Insulating member 75: Seal member 76: Boss 76a: Base 76b: Tip 77: Recess 78: Central portion 79: Upper end portion 80: Holder 94: Cylindrical portion 95: Base portion 96: Fixed portion 97: Through hole 99: Protruding portion 100: Power storage device 111: Main body 112: Cover portion

Claims (5)

An electrode assembly housed in a case;
An electrode terminal provided in the case;
Switching between a conductive state housed in the case and electrically connected to the electrode assembly and the electrode terminal and a non-conductive state in which the electrode assembly and the electrode terminal are electrically disconnected. A current interruption device,
The current interrupt device is
An energization plate electrically connected to the electrode assembly;
A first deformation plate electrically connected to the electrode terminal;
An insulating holder that is disposed between the energization plate and the case and supports the energization plate;
The first deforming plate is in contact with and electrically connected to the energizing plate in the conductive state, while being separated from the energizing plate and electrically non-conductive with the energizing plate in the non-conductive state. Connected,
The holder has a plurality of bosses arranged at intervals along the outer peripheral edge of the energization plate and projecting toward the energization plate side,
The plurality of bosses have a base portion that extends along an outer surface of the energization plate, and a tip portion that is bent from the base portion and extends along a surface opposite to the holder of the energization plate,
The electricity storage device is supported by the holder by being sandwiched between a surface on the electricity supply plate side of the holder and the tip portions of the plurality of bosses.   The power storage device according to claim 1, wherein tip ends of the plurality of bosses are bent toward a center of the current-carrying plate by a heat caulking process. An electrode assembly housed in a case;
An electrode terminal provided in the case;
Switching between a conductive state housed in the case and electrically connected to the electrode assembly and the electrode terminal and a non-conductive state in which the electrode assembly and the electrode terminal are electrically disconnected. A current interruption device,
The current interrupt device is
An energization plate electrically connected to the electrode assembly;
A first deformation plate electrically connected to the electrode terminal;
An insulating holder that is disposed between the energization plate and the case and supports the energization plate;
The first deforming plate is in contact with and electrically connected to the energizing plate in the conductive state, while being separated from the energizing plate and electrically non-conductive with the energizing plate in the non-conductive state. Connected,
The holder is disposed along the outer peripheral edge of the energization plate, and has an extending portion that protrudes toward the energization plate side.
The extending portion has a base portion extending along an outer surface of the energization plate, and a tip portion that is bent from the base portion and extends along a surface opposite to the holder of the energization plate,
The electricity storage device is supported by the holder by being sandwiched between the electricity supply plate side surface of the holder and the tip of the extending portion.   The power storage device according to claim 3, wherein the extending portion is bent toward the center of the energization plate by a heat caulking process. The current interrupting device is disposed on a side opposite to the first deforming plate with respect to the energizing plate, and a second deforming plate provided with a protrusion protruding toward a central portion of the energizing plate. Further comprising
When the electrode assembly and the electrode terminal are electrically connected, the second deformable plate is a first member in which the current plate and the first deformable plate are in contact with each other while the protrusion is located at the first position. When the state and the electrode assembly and the electrode terminal are non-conducting, the protrusion moves from the first position to the second position on the current-carrying plate side to separate the current-carrying plate and the first deformation plate. The power storage device according to any one of claims 1 to 4, wherein the power storage device is switched to a second state.

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