JP6498556B2 - Current interrupt device and power storage device using the same - Google Patents

Description

  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 interrupt device includes a current collector that is electrically connected to the power generation element in the case, a pressure-sensitive member that electrically connects the current collector and the electrode terminal, and a holder that supports the current collector. doing. When the pressure in the case increases, the pressure-sensitive member is deformed, and the electrical connection between the electrode terminal and the power generation element is interrupted. The current collector is fixed to the holder by a heat caulking process.

JP 2013-225500 A

  In the power storage device of Patent Document 1, an energizing plate used as a current collector is fixed to a holder by a heat caulking process. For this reason, the heat | fever at the time of a heat caulking process may be transmitted to a pressure sensitive member (what is called a deformation | transformation board), and there exists a possibility that the operating pressure of a pressure sensitive member may change. This specification discloses the technique which can suppress the change of the operating pressure of a deformation | transformation board.

  The current interrupt device disclosed in this specification is accommodated in a case. The current interrupting device electrically connects the electrode assembly housed in the case and the positive or negative terminal fixed to the wall surface of the case, and the electrode assembly when the internal pressure of the case rises above a predetermined value. The energization path that electrically connects the solid body and the terminal is cut off. The current interrupt device includes an energization plate, a first deformation plate, an insulating holder, and a metal member. The energization plate is electrically connected to the electrode assembly. The first deformation plate is electrically connected to the terminal and is disposed to face the energization plate. The holder is disposed between the wall surface of the case and the energization plate and accommodates the first deformation plate. The metal member is disposed outside the holder and the energization plate, is insulated from the electrode assembly, the energization plate, the first deformation plate, and the terminal, and sandwiches the holder and the energization plate. When the electrode assembly and the terminal are electrically connected, the first deformation plate is electrically connected while being in contact with the central portion of the energizing plate and the energizing plate, and the electrode assembly and the terminal are not electrically connected. In this case, it is electrically disconnected from the energizing plate while being separated from the energizing plate. The metal member has a base, a first bent portion, and a second bent portion. The base extends along the outer surface of the holder. The 1st bending part is provided in the edge part by the side of the wall surface of the case of a base. The 2nd bending part is provided in the edge part by the side of the electricity supply board of a base. Each of the first bent portion and the second bent portion bends inward of the holder and the current-carrying plate with respect to the base and extends inward. The outer edge portion of the holder and the outer edge portion of the energization plate are disposed between the first bent portion and the second bent portion, and are sandwiched between the first bent portion and the second bent portion. The outer surface of the holder is provided with a recess that is recessed inside the holder. The first bent portion of the metal member is disposed in the recess in a state in which the first bent portion is in contact with the entire inner wall surface of the recess without any gap.

  In the above current interrupting device, the metal member has the first bent portion and the second bent portion, and the first bent portion and the second bent portion sandwich the outer edge portion of the holder and the outer edge portion of the current-carrying plate. The energization plate is fixed to the holder. For this reason, a heat caulking process becomes unnecessary and it can suppress that the working pressure of a deformation | transformation board changes with a heat | fever.

  The present specification also discloses a power storage device including the above-described current interrupting device. The power storage device may be a secondary battery. According to this configuration, current can appropriately flow between the terminals.

  Details of the technology disclosed in this specification and further improvements will be described in detail in the detailed description and examples.

1 is a longitudinal sectional view of a power storage device according to Embodiment 1. FIG. The elements on larger scale of the dashed-two dotted line part 200 of FIG. It is the elements on larger scale near the negative electrode terminal of the electrical storage apparatus of Example 2, and shows the state which the electric current interruption apparatus does not operate | move. It is the elements on larger scale near the negative electrode terminal of the electrical storage apparatus of Example 2, and shows the state which the electric current interruption apparatus operated. The elements on larger scale near the recessed part of a holder.

  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.

(Feature 1) In the current interrupt device disclosed in the present specification, the first bent portion and the second bent portion of the metal member may be parallel. According to this configuration, the first bent portion and the second bent portion can appropriately sandwich the outer edge portion of the holder and the outer edge portion of the energizing plate.

(Feature 2) In the current interrupt device disclosed in the present specification, the first bent portion of the metal member may be insert-molded in the holder. According to this configuration, since the holder and the metal member are formed as an integral part by insert molding, the number of parts and the number of processes when manufacturing the current interrupting device 10 can be reduced, and the manufacturing efficiency can be improved.

(Characteristic 3) The current interrupting device disclosed in the present specification is disposed on the opposite side of the first deformation plate with respect to the energization plate, and is provided with a protrusion protruding 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 positioned at the first position when the electrode assembly and the terminal are in conduction and the energizing plate and the first deformable plate are in contact with each other, and the electrode assembly When the terminal is non-conductive, the protrusion 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.

  Hereinafter, the power storage device 100 according to the first embodiment will be described with reference to FIGS. 1 and 2. The power storage device 100 is a lithium ion secondary battery that is a type of secondary battery. 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 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. The inside of the case 1 is injected with an electrolytic solution, and the electrode assembly 3 is immersed in the electrolytic solution.

  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. Mounting holes 11 and 13 are formed in the lid portion 112 of the case 1. The terminal 5 is fixed to the mounting hole 11 and communicates with the inside and outside of the case 1. The terminal 7 is fixed to the mounting hole 13 and communicates with the inside and outside of the case 1. The lid 112 corresponds to an example of a “case wall surface”.

  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 is fixed to the terminal 5. A flat plate-like 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 60a is larger in size on the lower surface side than on the upper surface side. 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 gasket 63 is fixed to the terminal 7. A flat plate-like external terminal 61 is disposed on the upper surface of the gasket 63. A through hole similar to the through hole 60a of the external terminal 60 is formed in the external terminal 61. The head of the bolt 65 is accommodated in the through hole, and the shaft portion of the bolt 65 passes through the through hole and the external terminal 61 is passed through. Projecting upward. 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 14, a base portion 15, and a fixing portion 16. The cylindrical portion 14 is inserted through the mounting hole 13. A through hole 14 a is formed in the cylindrical portion 14. The base portion 15 is formed in an annular shape. The base portion 15 is located at the lower end portion of the cylindrical portion 14 and is disposed inside the case 1. A recess 15 a is formed in the base portion 15. The recess 15a communicates with the through hole 14a, and the interior of the recess 15a is maintained at atmospheric pressure. The fixed portion 16 is formed in an annular shape. The fixed portion 16 is located at the upper end portion of the cylindrical portion 14 and is disposed outside the case 1. The terminal 7 is fixed to the lid portion 112 of the case 1 by a fixing portion 16.

  A seal member 19 is disposed between the lid portion 112 of the case 1 and the terminal 7. The seal member 19 has an annular shape and goes around the cylindrical portion 14 of the terminal 7. The seal member 19 is in contact with the lower surface of the lid portion 112 of the case 1 and the inner peripheral surface of the mounting hole 13, and the base portion 15 and the cylindrical portion 14 of the terminal 7, thereby sealing the inside and outside of the case 1. Yes. The seal member 19 is made of a material having insulating properties and electrolyte resistance (perfluoroalkoxyalkane (PFA) in this embodiment). The lid portion 112 and the terminal 7 are insulated by the seal member 19. The material of the seal member 19 is not limited to this, and may be, for example, polytetrafluoroethylene (PTFE), polypropylene (PP), or the like.

  Next, the current interrupting device 10 will be described with reference to FIG. As shown in FIG. 2, the current interrupt device 10 includes a deformable plate 30, a current-carrying plate 20, a holder 80, and a metal member 90. The deformation plate 30 is a circular conductive diaphragm convex downward, and is formed of copper in this embodiment. The deformation plate 30 is disposed above the energizing plate 20 so as to face the energizing plate 20. The deformation plate 30 has a central portion 32 on the inner peripheral side and an outer peripheral portion 31 on the outer peripheral side. The central portion 32 is connected to a central portion 22 (described later) of the energization plate 20. The outer peripheral portion 31 is connected to the outer peripheral portion of the base portion 15 of the terminal 7. That is, the deformation plate 30 is electrically connected to the terminal 7. The recess 15 a of the base portion 15 is covered with the deformation plate 30. Since the inside of the recess 15 a is maintained at atmospheric pressure, atmospheric pressure acts on the upper surface of the deformation plate 30. The deformation plate 30 corresponds to an example of a “first deformation plate”.

  The current plate 20 is a conductive metal member, and is formed of copper in this embodiment. The energization plate 20 is formed in a circular shape having a larger diameter than the deformation plate 30 in plan view, and is disposed below the deformation plate 30. The upper surface of the energization plate 20 is flat and substantially parallel to the lid portion 112 of the case 1. A connection terminal 46 is connected to the energization plate 20. That is, the energization plate 20 is electrically connected to the electrode assembly 3 through the connection terminal 46 and the negative electrode lead 44. The energization 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 central portion 22 of the energizing plate 20 and the central portion 32 of the 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 20b 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 through the vent hole 20b. An annular insulating member 75 is disposed between the outer peripheral portion 31 of the deformation plate 30 and the outer peripheral portion 21 of the energizing plate 20.

  The holder 80 is disposed between the lid portion 112 of the case 1 and the energizing plate 20. The holder 80 accommodates the base portion 15 of the terminal 7, the deformation plate 30, and the insulating member 75 therein. The holder 80 is annular, and the terminal 7 is inserted through the center thereof. The holder 80 is formed of a material having insulation properties and resistance to electrolytic solution (in this embodiment, polyphenylene sulfide (PPS)).

  The holder 80 has an upper end portion 77 and a side portion 78. The upper end portion 77 is disposed between the lid portion 112 of the case 1 and the base portion 15 of the terminal 7. The upper end portion 77 is in contact with the lower surface of the lid portion 112 and the upper surface of the base portion 15, and serves as a spacer that determines the distance between the lid portion 112 and the base portion 15. The lid portion 112 and the base portion 15 are insulated by the upper end portion 77. The side portion 78 extends downward from the outer peripheral edge of the upper end portion 77. The side portion 78 accommodates the base portion 15, the deformation plate 30, and the insulating member 75 therein. The outer surface of the side portion 78 extends in a direction substantially orthogonal to the lid portion 112 of the case 1. A first bent portion 90 a (described later) of the metal member 90 is insert-molded on the side portion 78. A gap is formed between the upper surface of the outer peripheral portion of the side portion 78 and the lower surface of the lid portion 112 of the case 1. The lower surface of the side portion 78 is flat and is in contact with the upper surface of the energizing plate 20.

  The metal member 90 is disposed on the outer peripheral side of the holder 80 and the energizing plate 20. The metal member 90 has an annular shape and is made of stainless steel (SUS). The metal member 90 is insulated from the terminal 7 and the deformation plate 30 by the holder 80, and is insulated from the energizing plate 20 by an insulating member 76 (described later). The metal member 90 is also insulated from the electrode assembly 3 (see FIG. 1). The metal member 90 includes a first bent portion 90a provided at an upper end portion, a second bent portion 90c provided at a lower end portion, a lower end of the first bent portion 90a, and an upper end of the second bent portion 90c. Has a base 90b. The first bent portion 90 a is insert-molded on the outer surface of the side portion 78 on the entire circumference. For this reason, the 1st bending part 90a is contact | abutting with the side part 78 inside the side part 78 without gap. The first bent portion 90 a extends inside the side portion 78 substantially parallel to the lid portion 112 of the case 1. The base portion 90b extends in a direction substantially orthogonal to the first bent portion 90a, and is in contact with the outer surface of the side portion 78 and the insulating member 76 on the entire circumference. The second bent portion 90 c is bent at a substantially right angle toward the inner peripheral side with respect to the base portion 90 b in the entire periphery, and the upper surface thereof is disposed below the energizing plate 20 via the insulating member 76. That is, the first bent portion 90 a and the second bent portion 90 c are parallel to each other via the side portion 78 (strictly, the side portion 78 located below the first bent portion 90 a), the energizing plate 20 and the insulating member 76. Opposite. The outer peripheral portion of the side portion 78, the outermost peripheral portion of the outer peripheral portion 21 of the energization plate 20, and the insulating member 76 are disposed between the first bent portion 90a and the second bent portion 90c, and the first bent portion 90a and the second bent portion are arranged. It is sandwiched in the vertical direction by the portion 90c. Thereby, the electricity supply plate 20 is fixed to the holder 80. The upper side of the metal member 90 corresponds to an example of “the wall surface side of the case with respect to the holder”, and the lower side of the metal member 90 corresponds to an example of “the side of the energizing plate with respect to the holder”.

  The electric current interruption apparatus 10 is manufactured in the following procedures. First, an integrated part in which the holder 80 and the metal member 90 are integrated by insert molding is prepared. Specifically, the metal member 90 (specifically, the metal member 90 with the first bent portion 90a bent and the second bent portion 90c not yet bent) is inserted into the mold, and the first The melted PPS is injected around the bent portion 90a and solidified. Next, the terminal 7 is fixed to the mounting hole 13 of the lid portion 112 of the case 1 in a state where the integrated part and the seal member 19 are arranged on the outer peripheral side of the terminal 7. At this time, the second bent portion 90c extends downward along the base portion 90b. Subsequently, the deformation plate 30 is connected to the base portion 15 of the terminal 7. Next, the insulating member 75, the energizing plate 20, and the insulating member 76 are disposed below the outer peripheral portion of the deformation plate 30. Next, the second bent portion 90 c is bent at a substantially right angle from below to above using a jig, and the second bent portion 90 c is brought into contact with the lower surface of the insulating member 76. Thereby, the metal member 90 is caulked and fixed to the outer periphery of the holder 80 and the energizing plate 20. Next, the deformation plate 30 is irradiated with a laser beam from the outside of the case 1 through the through hole 14a of the terminal 7, and the central portion 32 of the deformation plate 30 and the central portion 22 of the energizing plate 20 are joined by welding. Thereby, the electric current interruption apparatus 10 is manufactured.

  According to the above manufacturing method, since the holder 80 and the metal member 90 are formed as an integral part by insert molding, the number of parts and the number of processes when manufacturing the current interrupting device 10 can be reduced, and manufacturing efficiency can be improved. Further, the first bent portion 90a and the second bent portion 90c face each other in parallel. For this reason, when the second bent portion 90 c is bent, the load exerted upward by the second bent portion 90 c acts on the first bent portion 90 a through the energizing plate 20 and the holder 80 at a substantially right angle. Therefore, the clamping force by the 1st bending part 90a and the 2nd bending part 90c improves, and the holder 80 and the electricity supply board 20 can be clamped reliably.

  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 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 power storage device 100 described above, the deformable plate 30 is electrically connected to the energizing plate 20 in contact with the central portion 22 of the energizing plate 20, and the terminal 5 and the terminal 7 can be energized. Is in a conductive state. 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 deformation plate 30 through the vent hole 20b increases. On the other hand, atmospheric pressure acts on the upper surface of the deformation plate 30. For this reason, when the internal pressure of the case 1 rises and reaches a predetermined value, the deformable plate 30 is reversed and changes to a convex state upward. Then, the energizing plate 20 connected to the central portion 32 of the deformable plate 30 breaks starting from the mechanically fragile groove portion 20a, and the deformable plate 30 becomes the remaining portion of the energizing plate 20 (the groove portion 20a of the energizing plate 20). It is separated from the outer peripheral part). As a result, the energization path connecting the energization plate 20 and the deformation plate 30 is interrupted, and the electrode assembly 3 and the terminal 7 are brought out of electrical conduction. At this time, the deformation plate 30 is insulated from the connection terminal 46, and the energization plate 20 is insulated from the terminal 7.

  The operation and effect of the current interrupt device 10 of the first embodiment will be described. In the current interrupt device 10, the first bent portion 90 a and the second bent portion 90 c of the metal member 90 sandwich the outer peripheral portion of the holder 80 and the outermost peripheral portion of the outer peripheral portion 21 of the energizing plate 20. Is fixed to the holder 80. For this reason, since the heat caulking process becomes unnecessary when fixing the electricity supply plate 20 to the holder 80, it can suppress that the operating pressure of the deformation | transformation board 30 changes with a heat | fever. The first bent portion 90 a is disposed inside the side portion 78. According to this configuration, since a part of the side portion 78 is interposed between the first bent portion 90a and the lid portion 112 of the case 1, even if the lid portion 112 is deformed inwardly for some reason, It becomes difficult to contact the 1st bending part 90a. That is, the part of the side portion 78 functions as a protective member for the first bent portion 90a. Since the electrolytic solution is injected into the case 1, if the contact portion between the lid portion 112 and the first bent portion 90a is immersed in the electrolytic solution, the contact portion may be corroded (so-called dissimilar metal contact corrosion). There is sex. According to the present embodiment, the occurrence of such a situation can be suppressed, and as a result, the characteristics of the current interrupting device 110 can be suppressed from deteriorating.

  Next, the power storage device of Example 2 will be described with reference to FIGS. 3 and 4. The two-dot chain line part 300 in FIG. 3 corresponds to the two-dot chain line part 200 in FIG. In this power storage device, the configuration of the current interrupt device 110 is different from the current interrupt device 10 of the first embodiment. The current interrupt device 110 includes a first deformation plate 130, a current supply plate 120, a holder 80, a metal member 90, and a second deformation plate 140. All of the first deformation plate 130, the energization plate 120, and the second deformation plate 140 are made of copper.

  The first deforming plate 130 and the energizing plate 120 have substantially the same configuration as the deforming plate 30 and the energizing plate 20 of the first embodiment, respectively. The space 150 between the first deformable plate 130 and the energizing plate 120 communicates with a space 154 (described later) between the energized plate 120 and the second deformable plate 140 through the vent hole 120b of the energized plate 120. Yes. A notch 80 a is formed on the lower surface on the inner peripheral side of the holder 80. A seal member 190 is disposed in the notch 80a. The seal member 190 is in contact with both the holder 80 and the energization plate 120, thereby sealing the space in the case 1, the space 150, and the space 154.

  The second deformation plate 140 is disposed below the energization plate 120. That is, the second deformation plate 140 is disposed on the opposite side of the first deformation plate 130 with respect to the energization plate 120. The center part of the second deformation plate 140 protrudes downward. The outer peripheral portion of the second deformation plate 140 is connected to the outer peripheral portion 121 of the energization plate 120. A projecting portion 142 projecting upward is provided at the center of the upper surface of the second deformable plate 140. Above the protrusion 142, the central portion 122 of the energization plate 120 (the portion surrounded by the groove 120a) is located. The pressure of the space 154 acts on the upper surface of the second deformation plate 140, and the pressure of the space in the case 1 acts on the lower surface of the second deformation plate 140. The protruding portion 142 corresponds to an example of a “projection”.

  As shown in FIG. 3, the current interrupt device 110 has an energization path that connects the connection terminal 46, the energization plate 120, the first deformation plate 130, 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 110.

  Here, the interruption | blocking operation | movement of the electric current interruption apparatus 110 is demonstrated. In the power storage device described above, the terminal 5 and the terminal 7 can be energized. When the internal pressure of the case 1 increases, the pressure acting on the lower surface of the second deformation plate 140 increases. On the other hand, the pressure of the space 154 sealed from the space in the case 1 acts on the upper surface of the second deformation plate 140. For this reason, when the pressure in the case 1 exceeds a predetermined value, the second deformable plate 140 changes from a downwardly convex state to an upwardly displaced state (see FIG. 4). At this time, the air in the space 154 moves to the space 150 through the vent hole 120b, and the pressure in the space 150 increases. When the second deformable plate 140 is displaced upward, the projecting portion 142 of the second deformable plate 140 collides with the central portion 122 of the energizing plate 120, and the energizing plate 120 is broken at the groove 120a. Thereby, the 1st deformation board 130 inverts and the center part 122 of the 1st deformation board 130 and the electricity supply board 120 displaces upwards (refer FIG. 4). For this reason, the electricity supply path which connects the electricity supply plate 120 and the 1st deformation plate 130 is interrupted | blocked, and the continuity between the electrode assembly 3 and the terminal 7 is interrupted | blocked. At this time, the first deformation plate 130 is insulated from the connection terminal 46, and the energization plate 120 is insulated from the terminal 7. The position of the protrusion 142 when the second deformation plate 140 is convex downward corresponds to an example of “first position”, and the protrusion 142 when the second deformation plate 140 is displaced upward. The position corresponds to an example of a “second position”. In addition, the state where the current plate 120 is not broken and is in contact with the first deformable plate 130 at the central portion 122 corresponds to an example of a “first state”. A state in which the first deformable plate 130 is electrically separated corresponds to an example of a “second state”. Also with this configuration, the same effects as the power storage device 100 of the first embodiment can be obtained.

  As described above, the embodiments of the technology disclosed in this specification have been described in detail. Includes modifications and changes.

  For example, in the above embodiment, the metal member 90 is annular, the first bent portion 90a is insert-molded in the holder 80 on the entire circumference, and the second bent portion 90c is applied to the lower surface of the insulating member 76 on the entire circumference. Although it touched, it is not restricted to this structure. For example, the first bent portion 90a may have a plurality of partial bent portions that are connected to the upper end of the base portion 90b at intervals in the circumferential direction. Similarly, the second bent portion 90c is There may be a plurality of partial bent portions connected to the lower end of the base portion 90b at intervals.

  Further, the metal member 90 may be assembled to the holder 80 by a method other than insert molding. One example will be described with reference to FIG. The current interrupting device shown in FIG. 5 has a plurality of arc-shaped metal members 290 instead of the annular metal member 90. In this configuration, a recessed portion 270 that is recessed toward the inner peripheral side of the holder 80 is formed on the outer surface of the side portion 78 of the holder 80. The first bent portion 290a of the metal member 290 has substantially the same shape as the recess 270. When the metal member 290 is assembled, the first bent portion of the metal member 290 (specifically, the first bent portion 290a is bent and the second bent portion 290c is not bent yet). 290a is inserted into the recess 270 of the holder 80, and then the second bent portion 290c is bent upward from below through the same procedure as in the first embodiment. Thereby, the holder 80 and the electricity supply plate 20 are clamped by the metal member 290. At this time, the 1st bending part 290a is arrange | positioned in the recessed part 270 in the state contact | abutted to the whole inner wall surface 278a, 278b, 278c of the recessed part 270 without a clearance gap. In addition, you may apply | coat an adhesive agent to the surface of the 1st bending part 290a, and may adhere and fix with the inner wall surfaces 278a-278c of the recessed part 270. FIG.

  Further, the entire first bent portion 90 a of the metal member 90 may not be arranged in the holder 80. For example, the upper end of the first bent portion 90 a to the middle is disposed in the holder 80, and the base portion 90 b may not be in contact with the outer surface of the holder 80. Moreover, the 1st bending part 90a and the 2nd bending part 90c do not need to be parallel.

  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. Moreover, in said Example, conduction | electrical_connection with the electricity supply board 20 is interrupted | blocked because the deformation | transformation board 30 inverts. However, the deformation method of the deformation plate 30 is not limited to inversion. For example, the configuration may be such that the central portion of the deformable plate 30 is bent upward so that the energizing plate 20 breaks starting from the groove portion 20a and the conduction between the deformable plate 30 and the energizing plate 20 is interrupted. The deformation plate 30 may be deformed in any way as long as the conduction between the deformation plate 30 and the energization plate 20 is interrupted. The same applies to the second deformation plate 140.

  Specific examples of the present invention have been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above. 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 interruption device 11, 13: Mounting hole 20: Current supply plate 21: Outer peripheral portion 22: Central portion 30: Deformation plate 80: Holder 90: Metal member 90a: No. 1 bent portion 90b: base portion 90c: second bent portion 100: power storage device 112: case lid portion 120: energizing plate 121: outer peripheral portion 122: central portion 130: first deformable plate 140: second deformable plate 142: protruding portion 270: Recesses 278a, 278b, 278c: Inner wall surface

Claims (5)

The electrode assembly housed in the case is electrically connected to the positive electrode or negative electrode terminal fixed to the wall surface of the case, and the internal pressure of the case exceeds a predetermined value. A current interrupting device that interrupts a current-carrying path that electrically connects the electrode assembly and the terminal when raised;
An energization plate electrically connected to the electrode assembly;
A first deformation plate that is electrically connected to the terminal and disposed opposite to the energization plate;
An insulating holder that is disposed between the wall surface of the case and the energization plate and accommodates the first deformation plate;
A metal member disposed outside the holder and the energization plate, insulated from the electrode assembly, the energization plate, the first deformation plate and the terminal; and a metal member sandwiching the holder and the energization plate; With
When the electrode assembly and the terminal are electrically connected, the first deformation plate is electrically connected while being in contact with the energizing plate at a central portion of the energizing plate, And when the terminal is non-conductive, it is electrically disconnected from the energizing plate in a state of being separated from the energizing plate,
The metal member includes a base portion extending along an outer surface of the holder, a first bent portion provided at an end portion of the base portion on the wall surface side, and an end portion of the base portion on the current-carrying plate side. Having a second bend provided,
Each of the first bent portion and the second bent portion is bent inward of the holder and the energization plate with respect to the base portion and extends inward.
The outer edge portion of the holder and the outer edge portion of the energizing plate are disposed between the first bent portion and the second bent portion, and are sandwiched between the first bent portion and the second bent portion,
The outer surface of the holder is provided with a recess recessed inside the holder,
The current interrupting device, wherein the first bent portion of the metal member is insert-molded in the holder, and is disposed in the recess in a state of being in contact with the entire inner wall surface of the recess without a gap.   The current interrupt device according to claim 1, wherein the first bent portion and the second bent portion of the metal member are parallel to each other. A second deformation plate is further provided on the opposite side of the current supply plate from the first deformation plate and provided with a protrusion protruding toward the central portion of the current supply plate. ,
The second deforming plate is in a first state in which when the electrode assembly and the terminal are electrically connected, the protrusion is positioned at the first position and the energizing plate and the first deforming plate are in contact with each other. And when the electrode assembly and the terminal are non-conductive, 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. It is switched to the second state, the current interrupting device according to claim 1 or 2. An electrical storage apparatus provided with the electric current interruption apparatus as described in any one of Claims 1-3 . The power storage device according to claim 4 , wherein the power storage device is a secondary battery.

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