JPWO2017034035A1 - Current interrupt device and power storage device using the same - Google Patents

Abstract

The power storage device 100 includes a case 1 that includes a terminal mounting surface 113, a terminal 7 that is mounted on the terminal mounting surface 113, and a current interrupt device 10 that is housed in the case 1 and includes a holder 80. The terminal 7 includes a large diameter portion 95, a small diameter portion 94, and a tip portion 96. A concave surface 79b and an abutting portion 79a that is located on at least one of the inner side and the outer side of the concave portion and that abuts against the inner surface of the terminal mounting surface 113 are formed on the opposing surface that faces the inner surface of the terminal mounting surface 113 of the holder 80. Has been. The recess 79 b accommodates at least a part of an insulating gasket 86 that seals between the inner surface of the terminal mounting surface 113 and the holder 80. When the terminal and the holder 80 are viewed along the axis of the small diameter portion 94, at least a part of the contact portion 79 a overlaps the tip portion 96.

Description

  This application claims priority based on Japanese Patent Application No. 2015-168278 filed on August 27, 2015. The entire contents of that application are incorporated herein by reference. The technology disclosed in this specification relates to a current interrupt device and a power storage device using the current interrupt 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.

JP 2013-225500 A

  By the way, when this type of current interrupting device is operated, a large voltage may be applied between the current collector plate and the electrode terminal. In such a case, if an electrolytic solution exists between the current collector plate and the electrode terminal, a conductive foreign matter is generated from the electrolytic solution, resulting in liquid junction, and there is a possibility that the current collector plate and the electrode terminal are reconnected. For this reason, in order to prevent such a liquid junction, a gasket may be arrange | positioned between the holder and case of an electric current interruption apparatus, and between the holder and a case may be sealed, and the penetration | invasion of electrolyte solution may be interrupted | blocked. However, in the conventional structure in which the gasket is arranged between the holder and the case, the case is bent due to the reaction force of the gasket and the seal is incomplete, or an excessive load acts on the gasket when the electrode terminal is assembled to the case. As a result, the gasket is broken. In the power storage device in which the gasket is disposed between the holder and the case, the present specification can suitably prevent the electrolyte from entering between the holder and the case while preventing the gasket from being broken. Disclosed is a current interrupt device and a power storage device using the same.

  The current blocking layer device disclosed in the present specification is equipped in a power storage device including a case having a terminal mounting surface, an electrode assembly housed in the case, and an electrode terminal mounted on the terminal mounting surface of the case. An insertion hole for communicating the inside of the case and the outside of the case is formed on the terminal mounting surface. The electrode terminal is located inside the case and has a large diameter portion that is larger than the diameter of the insertion hole, a small diameter portion that extends from the large diameter portion through the insertion hole toward the outside of the case, and the outside of the case. And a distal end portion that is bent from the small diameter portion and spreads outward. The current interrupt device is housed in a case and switches between a conductive state in which the electrode assembly and the electrode terminal are electrically connected and a non-conductive state in which the electrode assembly and the electrode terminal are electrically disconnected. . The current interrupt device includes a holder that accommodates the large-diameter portion, and a holder-side insertion hole through which the small-diameter portion is inserted is formed in the holder. The opposing surface that faces the inner surface of the terminal mounting surface of the holder has a recess that makes a round around the holder side insertion hole, and a contact that is located at least one of the inner side and the outer side of the concave portion and contacts the inner surface of the terminal mounting surface The part is formed. The recess houses at least a part of an insulating gasket that seals between the inner surface of the terminal mounting surface and the opposing surface of the holder. When the electrode terminal and the holder are viewed along the axis of the small diameter portion, at least a part of the contact portion overlaps the tip portion.

  In the above current interrupting device, the contact portion and the recess are formed on the opposing surface of the holder, and the contact portion is in contact with the inner surface of the terminal mounting surface. And when a holder and an electrode terminal are seen along the axial direction of the small diameter part of an electrode terminal, at least one part of the contact part has overlapped with the front-end | tip part. Therefore, the contact portion of the holder is in contact with the inner surface of the terminal mounting surface in the region where the compressive force from the tip portion of the electrode terminal acts. The load acting on the gasket accommodated in the concave portion of the holder is determined by the distance from the inner surface of the terminal mounting surface to the bottom surface of the concave portion of the holder, and this distance is determined by the holder. That is, it depends on the size of the contact portion and the size of the recess. Since the size of the holder can be managed, the load acting on the gasket can also be managed. For this reason, it is possible to prevent sealing failure due to excessive reaction force of the gasket and destruction of the gasket due to excessive load.

  The present specification also discloses another current interrupt device. A current interrupting device includes a case having a terminal mounting surface, an electrode assembly housed in the case, an electrode terminal mounted on the terminal mounting surface of the case, and a power storage device including a fastening member that fixes the case and the electrode terminal. Equipped. An insertion hole for communicating the inside of the case and the outside of the case is formed on the terminal mounting surface. The electrode terminal is provided inside the case and includes a large-diameter portion that is larger than the diameter of the insertion hole, and a small-diameter portion that extends from the large-diameter portion through the insertion hole toward the outside of the case. The large diameter portion and the small diameter portion are formed with through holes that communicate the inside of the case with the outside of the case. The fastening member includes a bolt disposed on the inner side of the case and a nut disposed on the outer side of the case and screwed to the bolt. The bolt includes a head that contacts the inner surface of the large-diameter portion and a shaft portion that is disposed in the through hole. The current interrupt device is housed in a case and switches between a conductive state in which the electrode assembly and the electrode terminal are electrically connected and a non-conductive state in which the electrode assembly and the electrode terminal are electrically disconnected. . The current interrupt device includes a holder that accommodates the large-diameter portion, and a holder-side insertion hole through which the small-diameter portion is inserted is formed in the holder. The opposing surface that faces the inner surface of the terminal mounting surface of the holder has a recess that makes a round around the holder side insertion hole, and a contact that is located at least one of the inner side and the outer side of the concave portion and contacts the inner surface of the terminal mounting surface The part is formed. The recess houses at least a part of an insulating gasket that seals between the inner surface of the terminal mounting surface and the opposing surface of the holder. When the fastening member and the holder are viewed along the axis of the small diameter portion, at least a part of the abutting portion overlaps with the head of the bolt and the nut.

  In the above current interrupting device, the contact portion and the recess are formed on the opposing surface of the holder, and the contact portion is in contact with the inner surface of the terminal mounting surface. And when a holder and a fastening member are seen along the axial direction of the small diameter part of an electrode terminal, at least one part of the contact part has overlapped with the head and nut of a volt | bolt. Therefore, in the region where the compression force (clamping force) from the bolt and nut acts, the contact portion of the holder is in contact with the inner surface of the terminal mounting surface. The load acting on the gasket is determined by the distance from the inner surface of the terminal mounting surface to the bottom surface of the concave portion of the holder, and this distance is determined by the holder. That is, it depends on the size of the contact portion and the size of the recess. Since the size of the holder can be managed, the load acting on the gasket can also be managed. For this reason, it is possible to prevent sealing failure due to excessive reaction force of the gasket and destruction of the gasket due to excessive load.

  The present specification also discloses a power storage device including the above-described current interrupt device.

FIG. 3 is a cross-sectional view of the power storage device of Example 1. The enlarged view of the broken-line part 200a of FIG. The principal part enlarged view of the electrical storage apparatus of Example 2 (equivalent to the broken line part 200a of FIG. 1). The principal part enlarged view of the electrical storage apparatus of Example 3 (equivalent to the broken line part 200a of FIG. 1). The principal part enlarged view of the electrical storage apparatus of Example 4 (equivalent to the broken line part 200a of FIG. 1). The principal part enlarged view of the electrical storage apparatus of Example 5 (equivalent to the broken line part 200a of FIG. 1). The principal part enlarged view of the electrical storage apparatus of Example 6 (equivalent to the broken line part 200a of FIG. 1).

  The main features of the embodiments described below are listed. 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 described in the claims at the time of filing. Absent.

(Characteristic 1) In the current interrupt device disclosed in the present specification, the bottom surface of the recess is separated from the inner surface and the outer surface of the recess, and goes around the recess and protrudes toward the inner surface of the terminal mounting surface. A convex portion may be formed. According to such a configuration, the gasket is partially and firmly pressed against the inner surface of the terminal mounting surface by the convex portion. On the other hand, at positions other than the convex portion, the gasket is suppressed from being firmly pressed against the inner surface of the terminal mounting surface. Thereby, destruction of a gasket can be suppressed, performing the seal between a holder and a case appropriately.

(Characteristic 2) In the current interrupt device disclosed in this specification, the bottom surface of the recess may have a first plane and a second plane. Moreover, the depth of the 1st plane part of a recessed part in the axial direction of the insertion hole of a terminal attachment surface may be deeper than the depth of the 2nd plane part of a recessed part. Even with such a configuration, the gasket is partially firmly pressed against the inner surface of the terminal mounting surface by the second plane, while an excessive load acting on the gasket by the first plane is suppressed. Thereby, there can exist an effect similar to the characteristic 1.

(Characteristic 3) In the current interrupt device disclosed in the present specification, in the radial direction of the recess, the first plane is formed on the outer peripheral side of the recess, and the second plane is formed on the inner peripheral side of the first plane of the recess. May be. According to such a structure, the position which seals between a holder and a case becomes an inner peripheral side, and a seal length can be shortened. For this reason, the seal | sticker between a holder and a case can be performed more appropriately.

(Characteristic 4) In the current interrupt device disclosed in the present specification, when the electrode terminal and the gasket are viewed along the axis of the small diameter portion, at least a part of the seal surface contacting the inner surface of the terminal mounting surface of the gasket is the tip portion. It may be duplicated. According to such a structure, the compressive force from the front-end | tip part of an electrode terminal can be made to act on a gasket efficiently, and the load concerning a gasket can be managed more suitably.

(Characteristic 5) The current interrupting device disclosed in the present specification further includes an energization plate electrically connected to the electrode assembly, and a first deformation plate supported by the holder and electrically connected to the electrode terminal. You may have. In addition, the first deformation 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. Also good.

(Characteristic 6) The current interrupt device disclosed in the present specification is disposed on the opposite side of the first deformation plate with respect to the energization plate, and provided with a protrusion that protrudes toward the central portion of the energization plate. The second deformation plate may be further 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 electrode terminal are non-conducting, the projection may be switched from the first position to the second position on the energizing plate side to be switched to the second state in which the energizing plate and the first deformation plate are separated from each other. .

  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. The lid portion 112 of the case 1 includes a terminal attachment surface 113. Insertion holes 81 and 82 are formed in the terminal attachment surface 113. The terminal 5 communicates with the inside and outside of the case 1 through the insertion hole 81, and the terminal 7 communicates with the inside and outside of the case 1 through the insertion hole 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 interrupting device 10 can switch the energization path between an electrically connected state and an electrically unconnected state. That is, 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. An external terminal 60 is disposed on the upper surface of the gasket 62. A through hole 60 a is formed in the external terminal 60. The through hole 60 a is larger in size on the lower surface side than the upper surface side of the external terminal 60. The gasket 62 insulates the lid portion 112 from the external terminal 60. The bolt 64 passes through the through hole 60a. Specifically, the head of the bolt 64 is accommodated in the through hole 60a. Further, the shaft portion of the bolt 64 protrudes above the external terminal 60 through the through hole 60a. 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. The terminal 7 includes a small diameter portion 94, a large diameter portion 95, and a tip portion 96. The large diameter portion 95 is disposed inside the case 1 and is formed in an annular shape. The diameter of the large-diameter portion 95 is larger than the diameter of the insertion hole 82, and the outer peripheral surface of the large-diameter portion 95 is in contact with the inner wall surface of the base portion 78 (detailed later) of the holder 80. A recess 98 is formed in the large diameter portion 95. The recess 98 communicates with the through hole 97, and the interior of the recess 98 is maintained at atmospheric pressure. The small diameter portion 94 is inserted into an insertion hole 76 a (described later) and an insertion hole 82 and communicates with the inside and outside of the case 1. The small diameter portion 94 is formed in an annular shape, and a through hole 97 is formed at the center thereof. The lower end of the small diameter portion 94 is fixed to the inner periphery of the large diameter portion 95. The distal end portion 96 is formed in an annular shape and is disposed at the upper end of the small diameter portion 94. The distal end portion 96 is disposed outside the case 1 and is formed to bend from the upper end of the small diameter portion 94 and spread outward in the radial direction. The terminal 7 is fixed to the outer surface of the terminal mounting surface 113 of the lid portion 112 of the case 1 by the tip end portion 96. A projecting portion 99 is formed on the large diameter portion 95. The protruding portion 99 is formed in an annular shape along the outer peripheral edge of the lower surface of the large diameter portion 95. The protruding portion 99 protrudes downward (on the side of the energizing plate 20 described later) from the lower surface of the large diameter 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 is convex 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 large diameter portion 95. Specifically, the outer peripheral portion 31 of the first deformable plate 30 is welded to a region of the lower surface of the large diameter portion 95 where the protruding portion 99 is not formed. When the first deformation plate 30 is connected to the lower surface of the large diameter 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 large diameter part 95 (namely, terminal 7) of the 1st deformation board 30 can be stabilized. The lower end of the recess 98 of the large diameter 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 circular 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. 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.

  The holder 80 is formed in an annular shape, and accommodates and holds the small diameter portion 94 and the large diameter portion 95 of the terminal 7, the first deformation plate 30, and the seal member 75 therein. The energization plate 20 is in contact with the lower surface of the holder 80. 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 a central portion 79, a base portion 78, and an upper end portion 76. The central portion 79 is disposed between the lower surface of the terminal mounting surface 113 of the lid portion 112 of the case 1 and the upper surface of the large diameter portion 95 of the terminal 7. The lower surface of the central portion 79 is in contact with the upper surface of the large diameter portion 95 of the terminal 7. On the upper surface of the central portion 79, a recess 79b is formed in an annular shape. The recess 79b makes a round around the upper end 76 (described later). The shape of the longitudinal section of the recess 79b is a rectangular shape. By forming the concave portion 79 b on the upper surface of the central portion 79, the central portion 79 is formed with an abutting portion 79 a in which the upper surface (the surface facing the terminal mounting surface 113) contacts the lower surface of the terminal mounting surface 113. ing. The contact portion 79a is formed inside and outside the recess 79b. An insulating gasket 86 is disposed between the lower surface of the terminal mounting surface 113 and the bottom surface of the recess 79b. The gasket 86 seals between the lid portion 112 (terminal mounting surface 113) of the case 1 and the holder 80 (concave portion 79b). That is, the gasket 86 is accommodated in the recess 79b in a state compressed in the vertical direction, and seals between the lower surface of the terminal mounting surface 113 and the bottom surface of the recess 79b. Since the recess 79 b goes around the upper end portion 76, the gasket 86 also goes around the upper end portion 76. A gap is formed between the gasket 86 and the inner surface of the recess 79b, and a gap is also formed between the gasket 86 and the outer surface of the recess 79b. That is, the dimensions (diameter and cross-sectional dimensions) of the gasket 86 are determined so that a gap is formed between the inner surface and the outer surface of the recess 79b.

  Here, when the terminal 7 and the holder 80 are viewed along the axial direction (the direction of the arrow A) of the small diameter portion 94 of the terminal 7, a part of the contact portion 79a of the holder 80 (the contact portion located on the inner side). 79 a) overlaps with the tip 96 of the terminal 7. That is, as shown in FIG. 2, in the axial direction of the small diameter portion 94, a part of the contact portion 79a is located within the range of S1 (within the range where the tip portion 96 is located). As is clear from FIG. 2, the gasket 86 is also located within the range of S <b> 1 and is in contact with the lower surface of the terminal mounting surface 113. Therefore, in this embodiment, the sealing surface of the gasket 86 (the surface in contact with the lower surface of the terminal mounting surface 113) is also located within the range of S1.

  The upper end portion 76 extends upward from the inner peripheral edge of the central portion 79. The upper end portion 76 is formed in an annular shape, and an insertion hole 76a is formed at the center thereof. The upper end portion 76 is located between the insertion hole 82 of the lid portion 112 and the small diameter portion 94 of the terminal 7, and the small diameter portion 94 is inserted into the insertion hole 76a as described above. The upper end of the upper end portion 76 is not in contact with the gasket 63. The insertion hole 76a corresponds to an example of a “holder side insertion hole” in the claims.

  The base portion 78 extends downward from the outer peripheral edge of the central portion 79. The base 78 is disposed between the lower surface of the lid portion 112 of the case 1 and the upper surface of the energization plate 20. The base 78 is formed in an annular shape, and accommodates the large-diameter portion 95 and the first deformation plate 30 therein. A first portion that contacts the outer peripheral surface of the large-diameter portion 95 and a recess 77 positioned below the first portion are formed on the inner surface of the base portion 78. The first portion is formed on the upper end side of the base portion 78, and the recess 77 is formed on the lower end side of the base portion 78. The diameter of the recess 77 is larger than the diameter of the large diameter portion 95 (the diameter of the first portion). Since the protruding portion 99 is formed on the lower surface of the large diameter portion 95, when the large diameter portion 95 is accommodated in the base portion 78, a part of the protruding portion 99 protrudes 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 base portion 78 is in contact with the upper surface of the energization plate 20.

  The seal member 75 is accommodated in a space outside the protruding portion 99 of the recess 77. The sealing member 75 goes around the outer peripheral side of the large diameter portion 95 of the terminal 7 in the circumferential direction. 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 protruding portion 99 formed on the lower surface of the large-diameter portion 95 is positioned below the upper end of the recess 77, but is not in contact with the current-carrying 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.

  The energization plate 20 and the holder 80 are fixed by a fixing member 70. The fixing member 70 is caulking and fixing the energizing plate 20 and the holder 80. An insulating member 71 is disposed inside the fixing member 70. The insulating member 71 insulates the energizing plate 20 from the fixing member 70.

  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 operation of the current interruption device 10 will be described. In the power storage device 100 described above, the terminal 5 and the terminal 7 are used in a conductive state in which current can be passed through an external device (for example, a generator or a motor). When the pressure in the case 1 increases due to overcharging of the power storage device 100 or the like, the pressure that acts on the lower surface of the energization plate 20 increases. 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 energizing plate 20 connected to the central portion 32 of the first deformable plate 30 breaks starting from the mechanically fragile groove 20a. Then, the first deformation plate 30 is inverted and changes to a convex state upward. 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 according to the first embodiment, the contact portion 79 a of the holder 80 is in contact with the inner surface of the terminal mounting surface 113 of the case 1. Further, the lower surface of the central portion 79 is in contact with the upper surface of the large diameter portion 95 of the terminal 7. When viewed along the axial direction of the small-diameter portion 94 of the terminal 7, a part of the contact portion 79 a overlaps the tip portion 96. Here, when the distal end portion 96 of the terminal 7 is caulked and fixed to the case 1, a load in the axial direction of the small diameter portion 94 acts on the distal end portion 96. In the power storage device 100 of the present embodiment, the load at the time of caulking and fixing the terminal 7 can be received by the contact portion 79a of the holder 80. Therefore, an excessive load is applied to the gasket 86 accommodated in the recess 79b. 86 can be prevented from being destroyed. Moreover, since the crushing margin of the gasket 86 can be easily managed by adjusting the depth of the recess 79b, the gap between the terminal mounting surface 113 and the holder 80 can be suitably sealed. Furthermore, a gap is formed between the gasket 86 and the inner and outer surfaces of the recess 79b, and a space for deforming the gasket 86 is secured in the recess 79b. As a result, an appropriate load acts on the gasket 86, and the gasket 86 can be prevented from being destroyed while properly sealing between the terminal mounting surface 113 and the holder 80. In the present embodiment, the contact portion 79a is formed inside and outside the recess 79b, but is not limited thereto. The contact portion 79a may be formed only outside the recess 79b. That is, the inner surface of the recess 79b and the outer peripheral surface of the upper end 76 may be configured as the same surface.

  Next, a power storage device of Example 2 will be described with reference to FIG. 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.

  As shown in FIG. 3, a recess 181 is formed in an annular shape on the upper surface of the holder 80. The recess 181 makes a round around the upper end 76 of the holder 80. A convex portion 182 that protrudes toward the terminal mounting surface 113 is formed on the bottom surface of the concave portion 181. The convex portion 182 is formed at a position separated from the inner side surface and the outer side surface of the concave portion 181, and goes around the upper end portion 76. The upper surface of the convex portion 182 is formed in parallel with the lower surface of the terminal mounting surface 113 (the surface on which the contact portion 79a contacts). A gasket 86 is disposed between the lower surface of the terminal mounting surface 113 and the upper surface of the convex portion 182. The gasket 86 seals between the terminal mounting surface 113 of the case 1 and the holder 80 (specifically, the convex portion 182). That is, the gasket 86 is accommodated in the concave portion 181 while being compressed in the vertical direction, and seals between the lower surface of the terminal mounting surface 113 and the upper surface of the convex portion 182. The gasket 86 is disposed in the recess 181 and makes a round around the upper end 76. In addition, it is preferable that the upper surface of the convex part 182 of the concave part 181 has higher flatness than the other part in the concave part 181, and the surface roughness is low.

  In the power storage device of Example 2, the seal area between the terminal mounting surface 113 and the holder 80 can be managed by appropriately changing the area of the upper surface of the convex portion. For this reason, management of the compression rate of the gasket 86 becomes easy, and the gap between the terminal mounting surface 113 and the holder 80 can be suitably sealed. Here, the compression rate refers to the height of the gasket 86 in a state in which the gasket 86 is released from an external force, and the height of the gasket 86 in a sealed state (in this embodiment, the lower surface of the terminal mounting surface 113 is convex. The distance to the upper surface of the portion 182).

  Also in the power storage device of Example 2, the contact portion 79 a of the holder 80 is in contact with the inner surface of the terminal mounting surface 113 of the case 1, and the lower surface of the central portion 79 of the holder 80 is the large diameter portion 95 of the terminal 7. It is in contact with the upper surface of. And a part of contact part 79a is located in the range of S1. For this reason, there can exist an effect similar to the electrical storage apparatus 100 of Example 1. FIG.

  Next, a power storage device of Example 3 will be described with reference to FIG. In the power storage device of the third embodiment, a recess 191 is formed on the upper surface of the holder 80. The recess 191 makes a round around the upper end 76 of the holder 80. The bottom surface of the recess 191 has a first plane 191a and a second plane 191b that is parallel to the first plane 191a. The first flat surface 191a is formed in a ring shape on the radially outer peripheral side of the recess 191. The second plane 191b is formed in a ring shape on the inner peripheral side from the first plane 191a. The depth of the first plane portion of the recess 191 is formed deeper than the depth of the second plane portion of the recess 191. As is clear from FIG. 4, a plane orthogonal to the first plane 191a is formed at the boundary between the first plane 191a and the second plane 191b. In other words, a step is formed at the boundary between the first plane 191 a and the second plane 191 b, and the step is formed so as to make a round around the upper end portion 76.

  A gasket 86 is disposed between the lower surface of the terminal mounting surface 113 and the bottom surface of the recess 191. The gasket 86 seals between the terminal mounting surface 113 and the holder 80 (specifically, the second flat surface 191b). That is, the gasket 86 is accommodated in the recess 191 in a state compressed in the vertical direction, and seals between the lower surface of the terminal mounting surface 113 and the second flat surface 191b. In addition, it is preferable that the upper surface of the second flat surface 191b of the concave portion 191 has higher flatness and lower surface roughness than other portions in the concave portion 191.

  In the power storage device according to the third embodiment, as in the power storage device according to the second embodiment, the compression rate of the gasket 86 can be easily managed, and the gap between the terminal mounting surface 113 and the holder 80 can be suitably sealed. Also with this configuration, it is possible to achieve the same effects as the power storage device of the first embodiment.

  Next, a power storage device of Example 4 will be described with reference to FIG. In the power storage device of the fourth embodiment, the configurations of the holder and the gasket are different from those of the first embodiment, and other configurations are the same as those of the first embodiment.

  The holder 180 is formed in an annular shape, and accommodates and holds the large-diameter portion 95 of the terminal 7, the first deformation plate 30, and the seal member 75 therein. As shown in FIG. 5, the holder 180 has an end 177 and a base 178. The end portion 177 is disposed between the lower surface of the terminal mounting surface 113 of the lid portion 112 of the case 1 and the upper surface of the large diameter portion 95 of the terminal 7. The lower surface of the end portion 177 is in contact with the upper surface of the large diameter portion 95. On the upper surface of the end portion 177, a recess 177b is formed in an annular shape. The shape of the longitudinal section of the recess 177b is formed in a rectangular shape. By forming the concave portion 177b on the upper surface of the end portion 177, the end portion 177 is formed with an abutting portion 177a in which the upper surface (the surface facing the terminal mounting surface 113) contacts the lower surface of the terminal mounting surface 113. ing. The contact portion 177a is formed outside the recess 177b in the radial direction. In addition, a facing portion 177c facing the lower surface of the terminal mounting surface 113 is formed inside the concave portion 177b in the radial direction. The facing portion 177c is located closer to the terminal mounting surface 133 than the recess 177b, but is not in contact with the lower surface of the terminal mounting surface 113, and a gap is formed between them. The configuration of the base portion 178 is the same as the configuration of the base portion 78 of the holder 80 of the first embodiment.

  An insulating gasket 186 is disposed between the lid portion 112 (terminal mounting surface 113) of the case 1 and the terminal 7. The gasket 186 is formed in an annular shape and abuts against the insertion hole 82 of the terminal mounting surface 113 and the small diameter portion 94 of the terminal 7, and contacts the lower surface of the terminal mounting surface 113 and the upper surface of the large diameter portion 95 of the terminal 7. Touching. The gasket 186 is compressed by the facing portion 177c, thereby sealing between the lower surface of the terminal mounting surface 113 and the facing portion 177c (that is, between the lower surface of the terminal mounting surface 113 and the holder 180). The outer peripheral end of the gasket 186 is located inside the recess 177b. Specifically, a portion of the gasket 186 is compressed in the vertical direction by the facing portion 177c, so that a portion (outer peripheral end portion) is accommodated in the recess 177b.

  In the power storage device according to the fourth embodiment, as in the power storage device according to the second embodiment, the compression rate of the gasket 186 can be easily managed. That is, since the seal area can be managed by appropriately changing the area of the facing portion 177c, the gap between the terminal mounting surface 113 and the holder 180 can be suitably sealed. Also with this configuration, it is possible to achieve the same effects as the power storage device of the first embodiment.

  The gasket 186 may be configured such that a part of the gasket 186 is accommodated in the recess 177b before being compressed by the facing portion 177c. Further, in this configuration, when the gasket 186 is compressed in the vertical direction by the facing portion 177c, the volume of the portion of the gasket 186 that is accommodated in the recess 177c may be increased.

  Next, a power storage device of Example 5 will be described with reference to FIG. In the present embodiment, only differences from the fourth embodiment will be described. The power storage device of the present embodiment is different from that of the fourth embodiment in the configuration of the terminals, and further includes a fastening member 220 that fixes the terminal and the case.

  As shown in FIG. 6, the terminal 17 includes a small diameter portion 194 and a large diameter portion 195. In other words, as is apparent from a comparison between the power storage device of the fourth embodiment (FIG. 4) and the power storage device of the present embodiment (FIG. 5), the terminal 17 has the tip 96 of the terminal 7 of the fourth embodiment. There is no configuration. The upper end of the small diameter portion 194 is located on the substantially same plane as the external terminal 61.

  The fastening member 220 includes a bolt 221 and a nut 222. The terminal 17 and the case 1 are fastened by a bolt 221 and a nut 222. The bolt 221 is inserted into the through hole 97 from the inside of the case. The bolt 221 has a head portion 221a and a shaft portion 221b. The head 221 a is disposed on the inner side of the case 1 and is in contact with the inner surface of the large diameter portion 195. The shaft portion 221 b is inserted into the through hole 97 and protrudes to the outside of the case 1. On the upper surface of the small diameter portion 194 and the upper surface of the external terminal 61, a nut 222 is screwed to the shaft portion 221b. The terminal 17 is fixed to the case 1 by screwing the nut 222 into the bolt 221. The bolt 221 and the nut 222 are made of, for example, a conductive metal. The material of the bolt 221 and the nut 222 is not limited to this, and may be made of, for example, an insulating material.

  When the fastening member 220 (bolt 221, nut 222) and the holder 180 are viewed along the axial direction (direction of arrow B) of the small diameter portion 194 of the terminal 17, a part of the contact portion 177 a of the holder 180 is the bolt 221. And the nut 222. That is, as shown in FIG. 6, in the axial direction of the small diameter portion 194, a part of the contact portion 177a is located within the range of S2 (within the range where the head portion 221a of the bolt 221 and the nut 222 are located). . As is clear from FIG. 6, the gasket 186 is also located within the range of S <b> 2 and is in contact with the lower surface of the terminal mounting surface 113. Therefore, the sealing surface of the gasket 186 (the surface in contact with the lower surface of the terminal mounting surface 113 and the upper surface of the facing portion 177c) is also located within the range of S2.

  In the power storage device of Example 5, the contact portion 177 a of the holder 180 is in contact with the inner surface of the terminal mounting surface 113. Further, the lower surface of the end portion 177 is in contact with the upper surface of the large-diameter portion 195 of the terminal 17. When viewed along the axial direction of the small diameter portion 194 of the terminal 17, a part of the contact portion 177 a overlaps with the bolt 221 and the nut 222. Here, when the terminal 17 is fixed to the case 1 by the fastening member 220, the axial load of the small diameter portion 94 acts on the holder 180 and the gasket 186. In the power storage device of this embodiment, the load can be received by the contact portion 177a of the holder 180, so that an excessive load is applied to the gasket 186 and the gasket 186 can be prevented from being broken. Further, by adjusting the height and area of the facing portion 177c, the crushing margin of the gasket 186 can be easily managed, so that the gap between the terminal mounting surface 113 and the holder 180 can be suitably sealed. In addition, you may use the structure of the terminal 17 and the fastening member 220 of a present Example for another Example.

  Next, a power storage device of Example 6 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 shown in FIG. 7, the current interrupt device 10 a includes an energization plate 20, a first deformation plate 30, and a 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 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 continuity 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 sixth embodiment, since the configurations of the terminal mounting surface 113 of the case 1 and the holder 80 are the same as those of the power storage device 100 of the first embodiment, the same effects as the power storage device 100 of the first embodiment are obtained. Can play. In addition, said electric current interruption apparatus 10a may be attached to any electrical storage apparatus of Examples 1-5.

  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 the third embodiment, the first plane 191a and the second plane 191b formed in the recess 191 of the holder 80 may be formed on the radially inner peripheral side of the recess 191. And the 2nd plane 191b may be formed in the perimeter side from the 1st plane 191a. Also with this configuration, the same effects as those of the third embodiment can be achieved.

  Further, the current interrupting devices 10 and 10a may be provided on the terminal 5 side, or may be provided on both the terminal 5 and the terminal 7. 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.

  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 41: Positive electrode current collection tab 42: Negative electrode current collection tab 43: Positive electrode lead 44: negative electrode lead 46: connection terminal 60, 61: external terminal 62, 63: gasket 64, 65: bolt 75: seal member 76: upper end 76a: insertion hole 77: recess 78: base 79: central portion 79a: Contact portion 79b: concave portion 80: holder 81, 82: insertion hole 86: gasket 94: small diameter portion 95: large diameter portion 96: tip portion 97: through hole 100: power storage device 111: main body 112: lid portion 113: terminal mounting surface

Claims (9)

A case with a terminal mounting surface;
An electrode assembly housed in the case;
An electrode terminal attached to the terminal attachment surface of the case, and
The terminal mounting surface is formed with an insertion hole that communicates the inside of the case with the outside of the case.
The electrode terminal is located inside the case and has a large diameter portion that is larger in diameter than the diameter of the insertion hole, and a small diameter portion that extends from the large diameter portion to the outside of the case through the insertion hole. , The outside of the case is equipped with a power storage device comprising a tip portion that is bent from the small diameter portion and spreads outward,
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 interrupting device,
A holder for accommodating the large diameter portion;
The holder has a holder side insertion hole through which the small diameter portion is inserted,
The opposing surface of the holder facing the inner surface of the terminal mounting surface is a recess that makes a round around the holder side insertion hole, and is located at least one of the inner side and the outer side of the concave portion, and the inner surface of the terminal mounting surface An abutting portion that abuts, and
The recess contains at least a part of an insulating gasket that seals between the inner surface of the terminal mounting surface and the opposing surface of the holder,
The current interrupting device, wherein when the electrode terminal and the holder are viewed along the axis of the small diameter portion, at least a part of the contact portion overlaps the tip portion. A case with a terminal mounting surface;
An electrode assembly housed in the case;
An electrode terminal attached to the terminal attachment surface of the case;
A fastening member for fixing the case and the electrode terminal;
The terminal mounting surface is formed with an insertion hole that communicates the inside of the case with the outside of the case.
The electrode terminal is located inside the case and has a large diameter portion that is larger in diameter than the diameter of the insertion hole, and a small diameter portion that extends from the large diameter portion to the outside of the case through the insertion hole. , And
In the large diameter portion and the small diameter portion, a through hole that communicates the inside of the case and the outside of the case is formed,
The fastening member includes a bolt disposed on the inner side of the case, and a nut disposed on the outer side of the case and screwed to the bolt.
The bolt is equipped in a power storage device including a head that contacts the inner surface of the large-diameter portion, and a shaft portion disposed in the through-hole,
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 interrupting device,
A holder for accommodating the large diameter portion;
The holder has a holder side insertion hole through which the small diameter portion is inserted,
The opposing surface of the holder facing the inner surface of the terminal mounting surface is a recess that makes a round around the holder side insertion hole, and is located at least one of the inner side and the outer side of the concave portion, and the inner surface of the terminal mounting surface An abutting portion that abuts, and
The recess contains at least a part of an insulating gasket that seals between the inner surface of the terminal mounting surface and the opposing surface of the holder,
The current interrupting device, wherein when the fastening member and the holder are viewed along the axis of the small diameter portion, at least a part of the abutting portion overlaps the head of the bolt and the nut.   The convex part which protrudes toward the inner surface of the said terminal attachment surface is formed in the bottom face of the said recessed part while separating from the inner surface and outer surface of the said recessed part, and making a round in the said recessed part. Or the electric current interruption apparatus of 2. The bottom surface of the recess has a first plane and a second plane,
3. The current interrupting device according to claim 1, wherein a depth of the first plane portion of the recess in the axial direction of the insertion hole of the terminal mounting surface is deeper than a depth of the second plane portion of the recess.   The said 1st plane is formed in the outer peripheral side of the said recessed part in the radial direction of the said recessed part, The said 2nd plane is formed in the inner peripheral side rather than the said 1st plane of the said recessed part. Current interrupting device.   When the electrode terminal and the gasket are viewed along the axis of the small-diameter portion, at least a part of the seal surface that abuts the inner surface of the terminal mounting surface of the gasket overlaps the tip portion. The current interrupting device according to claim 5. An electricity supply plate electrically connected to the electrode assembly, and a first deformation plate supported by the holder and electrically connected to the electrode terminal,
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. The current interrupting device according to any one of claims 1 to 6, which is connected. A second deformation plate that is disposed on the opposite side to the first deformation plate with respect to the current supply plate, and is provided with a protrusion protruding toward the center of the current supply plate;
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 current interrupting device according to claim 7, wherein the current interrupting device is switched to a second state.   An electrical storage apparatus provided with the electric current interruption apparatus as described in any one of Claims 1-8.

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