Storage cell and method for short-circuiting between lid and external terminal

Abstract

To provide a power storage cell capable of suppressing re-inversion of an inversion plate, and a method of short-circuiting between a lid and an external terminal.SOLUTION: A power storage cell 1 includes an electrode body, a cell case, and an external terminal 300. The cell case has a case body and a lid. The lid has a lid body 222 charged positively or negatively, an inversion plate 224 that is able to short-circuit between the lid body and the external terminal, and a regulation part 226 connected to the inversion plate. The inversion plate is deformable between a steady-state shape curved to be convex in a direction separated from the external terminal and an inverted shape curved to be convex toward the external terminal and contacting the external terminal. The lid body has a receiving portion 223 that receives the regulation part when the inversion plate is in the inverted shape. The receiving portion 223 allows the regulation part 226 to pass therethrough when the inversion plate deforms from the steady-state shape to the inverted shape, and comes into contact with the regulation part 226 when the inversion plate is in the inverted shape.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to an electricity storage cell and a method for shorting between a lid and an external terminal. [Background technology]

[0002] Japanese Patent Application Laid-Open Publication No. 2015-204284 discloses a storage cell including an electrode assembly, a case that houses the electrode assembly, and a cap assembly connected to the case. The case opens upward. The cap assembly includes a cap plate fixed to the opening of the case, a pair of terminal plates connected to the upper surface of the cap plate, and an inversion plate connected to the cap plate. The cap plate is electrically connected to a positive terminal plate, and the inversion plate is electrically connected to the cap plate. A negative terminal plate is disposed above the inversion plate.

[0003] When the inversion plate is inverted in the above-mentioned storage cell, the inversion plate comes into contact with the negative terminal plate, and the positive terminal plate and the negative terminal plate are short-circuited via the inversion plate and the cap plate, causing a short-circuit current to flow through the inversion plate. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2015-204284 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the energy storage cell described in JP 2015-204284 A, there is a concern that the reversal plate may be reversed again in a direction away from the terminal plate due to vibration or the like. An object of the present disclosure is to provide a storage cell capable of suppressing reversal of a reversal plate and a method for short-circuiting between a lid and an external terminal. [Means for solving the problem]

[0006] According to one aspect of the present disclosure, there is provided a storage cell comprising an electrode assembly, a cell case that houses the electrode assembly, and an external terminal fixed to an upper surface of the cell case, the cell case having a case body that houses the electrode assembly and has an opening that opens upward, and a lid connected to the case body so as to close the opening of the case body, the lid being connected to the opening of the case body and including a lid body that is charged to a positive electrode or a negative electrode of the electrode assembly, an inversion plate that is connected to the lid body and is capable of short-circuiting the lid body and the external terminal, and a regulating portion connected to the inversion plate. and the inversion plate is deformable between a steady shape in which it is curved so as to be convex in a direction away from the external terminal and an inverted shape in which it is curved so as to be convex toward the external terminal and in contact with the external terminal, the lid body has a receiving portion that receives the regulating portion when the inversion plate is in the inverted shape, the receiving portion allows the regulating portion to pass when the inversion plate deforms from the steady shape to the inverted shape, and abuts against the regulating portion when the inversion plate is in the inverted shape, thereby regulating the deformation of the inversion plate in the inverted shape toward the steady shape.

[0007] A method for short-circuiting between a lid and an external terminal according to one aspect of the present disclosure is a method for short-circuiting between the lid and the external terminal in an energy storage cell comprising: an electrode body, a cell case that accommodates the electrode body, and an external terminal fixed to an upper surface of the cell case, wherein the cell case has a case body that accommodates the electrode body and has an opening that opens upward, and a lid connected to the case body so as to close the opening of the case body, wherein the lid has a lid body that is charged with a positive electrode or a negative electrode of the electrode body, an inversion plate that is connected to the lid body and is capable of short-circuiting the lid body and the external terminal, and a regulating portion connected to the inversion plate, and the lid body has a receiving portion that receives the regulating portion, wherein when an internal pressure of the cell case reaches or exceeds a predetermined pressure, the inversion plate is inverted and the receiving portion is passed through the regulating portion, and while the inversion plate is in contact with the external terminal, the regulating portion is abutted against the receiving portion, thereby maintaining a contact state of the inversion plate with the external terminal. Effect of the Invention

[0008] According to the present disclosure, it is possible to provide a storage cell capable of suppressing reversal of the reversal plate, and a method for short-circuiting between a lid and an external terminal. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a perspective view illustrating a schematic configuration of a storage cell according to a first embodiment of the present disclosure. [Diagram 2] FIG. 2 is an exploded perspective view of the power storage cell shown in FIG. [Diagram 3] FIG. 2 is a cross-sectional view of the storage cell shown in FIG. [Figure 4] FIG. 2 is an enlarged cross-sectional view of the vicinity of the reversal plate. [Diagram 5] FIG. 11 is a cross-sectional view illustrating a schematic state of the reversal plate after operation. [Figure 6] FIG. 11 is an enlarged cross-sectional view of the vicinity of the reversal plate in the modified example. [Figure 7] FIG. 7 is a cross-sectional view that illustrates a schematic state of the reversal plate illustrated in FIG. 6 after the reversal plate is operated. [Figure 8] FIG. 11 is an enlarged cross-sectional view of the vicinity of the reversal plate in the modified example. [Figure 9] FIG. 9 is a cross-sectional view that illustrates a schematic state of the reversal plate illustrated in FIG. 8 after the operation. [Figure 10] FIG. 11 is an enlarged cross-sectional view of the vicinity of the reversal plate in the modified example. [Figure 11] FIG. 11 is a cross-sectional view that illustrates a state after the reversal plate illustrated in FIG. 10 is operated. [Figure 12] FIG. 11 is an enlarged cross-sectional view of the vicinity of the reversal plate in the modified example. [Figure 13] FIG. 13 is a cross-sectional view that illustrates a state after the reversal plate illustrated in FIG. 12 is operated. [Figure 14] FIG. 4 is a perspective view illustrating a schematic configuration of a storage cell according to a second embodiment of the present disclosure. [Figure 15] FIG. 15 is an exploded perspective view of the electricity storage cell shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present disclosure will now be described with reference to the accompanying drawings, in which the same or corresponding components are designated by the same reference numerals.

[0011] (First embodiment) Fig. 1 is a perspective view that illustrates a schematic diagram of a storage cell according to a first embodiment of the present disclosure. Fig. 2 is an exploded perspective view of the storage cell illustrated in Fig. 1. Fig. 3 is a cross-sectional view of the storage cell illustrated in Fig. 1.

[0012] As shown in FIGS. 1 to 3, the energy storage cell 1 includes an electrode assembly 100, a cell case 200, an external terminal 300, a connecting member 400, and an insulating member 500. The electrode assembly 100 includes an electrode body 100, a cell case 200, an external terminal 300, a connecting member 400, and an insulating member 500.

[0013] The electrode assembly 100 has a plurality of unit electrode bodies 111, 112 and an insulating film 120. In this embodiment, the plurality of unit electrode bodies includes two unit electrode bodies 111, 112. Each unit electrode body 111, 112 includes a plurality of tabs, i.e., a plurality of positive electrode tabs 110P and a plurality of negative electrode tabs 110N. The unit electrode bodies 111, 112 have the same structure. Therefore, hereinafter, only the unit electrode body 111 will be described.

[0014] The electrode unit 111 includes a positive electrode sheet, a separator, and a negative electrode sheet. The positive electrode sheet, the negative electrode sheet, and the separator are formed into a long rectangular shape.

[0015] The positive electrode sheet includes a metal foil and a positive electrode composite layer provided on the metal foil. An uncoated portion where the positive electrode composite layer is not formed is formed on the upper long side of the metal foil, and the positive electrode tabs 110P are formed at intervals from each other in the uncoated portion.

[0016] The negative electrode sheet includes a metal foil and a negative electrode composite layer formed on the metal foil. An uncoated portion where the negative electrode composite layer is not formed is formed on the upper long side of the metal foil, and the negative electrode tabs 110N are formed at intervals from each other on the uncoated portion.

[0017] In a state where each sheet is wound, the positive electrode tabs 110P are arranged in the thickness direction (a direction perpendicular to the paper surface in FIG. 3), and the negative electrode tabs 110N are arranged in the thickness direction. The positive electrode tabs 110P and the negative electrode tabs 110N are arranged at intervals in the width direction (a direction perpendicular to both the thickness direction and the height direction).

[0018] The insulating film 120 has a shape that collectively covers the peripheral and bottom surfaces of the plurality of unit electrode bodies 111 and 112 .

[0019] The cell case 200 houses the electrode assembly 100. The cell case 200 also houses an electrolyte (not shown). The cell case 200 is sealed. The cell case 200 has a case body 210 and a lid 220.

[0020] The case body 210 has an opening 211 that opens upward. The case body 210 is made of a metal such as aluminum. The case body 210 has a bottom wall 212 and a peripheral wall 214. The bottom wall 212 is formed in a rectangular, flat plate shape. The peripheral wall 214 stands up from the bottom wall 212. The peripheral wall 214 is formed in a rectangular tube shape. The length of the peripheral wall 214 in the width direction is longer than the length of the peripheral wall 214 in the thickness direction. The length of the peripheral wall 214 in the height direction is longer than the length of the peripheral wall 214 in the thickness direction.

[0021] The lid 220 closes the opening 211 of the case body 210. The lid 220 is connected to the opening 211 by welding or the like. The lid 220 is formed in a flat plate shape. The lid 220 is made of a metal such as aluminum. The lid 220 has a lid body 222, a reversible plate 224, and a restricting portion 226.

[0022] The lid body 222 is connected to the case body 210 by welding or the like. The lid body 222 is formed with a pressure release valve 222a, a liquid injection hole 222b, a sealing member 222c, and a pair of pin insertion holes 222d.

[0023] The pressure release valve 222a is formed in the center of the lid body 222. The pressure release valve 222a is formed to break when the internal pressure of the cell case 200 reaches or exceeds a predetermined pressure. When the pressure release valve 222a breaks, gas within the cell case 200 is released to the outside of the cell case 200 through the pressure release valve 222a, and the internal pressure of the cell case 200 decreases.

[0024] The liquid injection hole 222b is a through-hole for injecting an electrolyte into the cell case 200 during the manufacturing process of the energy storage cell 1.

[0025] The sealing member 222c is a member that seals the liquid injection hole 222b. After the electrolyte is injected into the case body 210, the liquid injection hole 222b is sealed with the sealing member 222c.

[0026] The pair of pin insertion holes 222d are formed at an interval from each other in the width direction. Each of the pin insertion holes 222d is a through hole for inserting a connecting pin 420 described later.

[0027] The reversible plate 224 is connected to the lid body 222 by welding or the like. The reversible plate 224 is capable of short-circuiting the lid body 222 and the external terminal 300. As shown in Fig. 4, the reversible plate 224 has a base portion 224a and a reversible portion 224b.

[0028] The base 224a is connected to the lid body 222 by welding or the like. In this embodiment, the base 224a is connected to a portion of the lid body 222 that is located below a negative electrode terminal plate 330 (described later). The base 224a is formed in an annular shape, more specifically, in a circular ring shape.

[0029] The inverted portion 224b is connected to the inside of the base portion 224a. The inverted portion 224b is formed in a disk shape. The inverted portion 224b can be deformed between a normal shape (shape shown in FIG. 4) curved so as to be convex in a direction away from the negative electrode terminal plate 330 and an inverted shape (shape shown in FIG. 5) curved so as to be convex toward the negative electrode terminal plate 330 and in contact with the negative electrode terminal plate 330. When the internal pressure of the cell case 200 is less than a predetermined pressure (normal state), the inverted portion 224b has a normal shape as shown in FIG. 4. When the internal pressure of the cell case 200 becomes equal to or greater than the predetermined pressure, the inverted portion 224b is deformed from the normal shape to an inverted shape as shown in FIG. 5. As a result, the inverted portion 224b comes into contact with the negative electrode terminal plate 330.

[0030] The restricting portion 226 is connected to the inverting plate 224. More specifically, the restricting portion 226 is connected to the lower surface of the inverting portion 224b. The restricting portion 226 is made of an elastically deformable material. The restricting portion 226 restricts the deformation of the inverting portion 224b from the inverted shape to a normal shape. The restricting portion 226 has a fixing portion 226a and a leg portion 226b.

[0031] The fixed portion 226a is a portion fixed to the lower surface of the inverted portion 224b. The fixed portion 226a is fixed to the top portion 224b1 of the inverted portion 224b. In this embodiment, the fixed portion 226a has a shape that extends in a direction away from the inverted portion 224b.

[0032] The leg portion 226b extends from the fixed portion 226a. The leg portion 226b may have a plurality of leg elements extending from the fixed portion 226a toward the outside in the radial direction of the inverted portion 224b. The plurality of leg elements are arranged at intervals from each other in the circumferential direction of the inverted portion 224b. The leg portion 226b may be formed in a circular ring shape.

[0033] 4 and 5, the lid body 222 has a receiving portion 223 that receives the restricting portion 226 when the reversible plate 224 is in the inverted shape. The receiving portion 223 is provided at a position of the lid body 222 that overlaps with the reversible plate 224 in the height direction. The receiving portion 223 allows the restricting portion 226 to pass when the reversible plate 224 deforms from the normal shape to the inverted shape. On the other hand, the receiving portion 223 abuts against the restricting portion 226 when the reversible plate 224 is in the inverted shape, thereby restricting the deformation of the reversible plate 224 in the inverted shape toward the normal shape.

[0034] The outer end of the leg 226b faces the receiving portion 223. As shown in Fig. 4 and Fig. 5, the length between the outer end of the leg 226b in the width direction is greater than the length between the receiving portions 223 in the same direction. However, when the inverted portion 224b deforms from the normal shape to the inverted shape, the leg 226b passes through the receiving portion 223 by elastically deforming. After the leg 226b passes through the receiving portion 223 when the inverted portion 224b is inverted, the leg 226b abuts against the receiving portion 223.

[0035] The external terminal 300 is fixed to the upper surface of the cell case 200. A bus bar (not shown) is connected by welding or the like to the external terminal 300. The external terminal 300 has a positive electrode member 300P and a negative electrode member 300N.

[0036] The positive electrode member 300P is connected by welding or the like to the upper surface of the cell case 200. The positive electrode member 300P has a positive electrode terminal plate 310 and a terminal block 320.

[0037] The positive electrode terminal plate 310 is formed in a rectangular parallelepiped shape and is made of a metal such as aluminum.

[0038] The terminal block 320 is formed in a rectangular parallelepiped shape. The terminal block 320 is made of a metal (such as iron) different from the metal constituting the positive electrode terminal plate 310. The terminal block 320 is connected to the upper surface of the lid body 222 by welding, and the positive electrode terminal plate 310 is connected to the upper surface of the terminal block 320 by welding or the like. In other words, the case body 210 and the lid 220 are electrically connected to the positive electrode terminal plate 310 via the terminal block 320, and are charged with the same polarity as the positive electrode terminal plate 310. Each of the positive electrode terminal plate 310 and the terminal block 320 has a through hole formed therein for inserting a positive electrode connecting pin 420P described later.

[0039] The negative electrode member 300N is connected to the upper surface of the cell case 200 by welding or the like. The negative electrode member 300N is disposed at a distance in the width direction from the positive electrode member 300P. The negative electrode member 300N has a negative electrode terminal plate 330 and an insulating plate 340.

[0040] The negative electrode terminal plate 330 is formed in a substantially rectangular parallelepiped shape. The negative electrode terminal plate 330 is disposed above the reversal plate 224. As shown in Fig. 4, the negative electrode terminal plate 330 has a facing portion 332 facing the reversal plate 224. The facing portion 332 is formed flat.

[0041] In this embodiment, the negative electrode terminal plate 330 has a protruding portion 333 protruding from the opposing portion 332 toward the reversal plate 224. The protruding portion 333 may be formed in an annular shape, or may have a pair of protruding elements arranged at positions sandwiching the central axis L (see FIG. 5) of the reversal portion 224b in the width direction. As shown in FIG. 4 and FIG. 5, the protruding portion 333 has a contact surface 333a having a shape that follows the outer shape of the reversal plate 224 in the inverted shape. As described above, when the internal pressure of the cell case 200 is less than a predetermined pressure (normal), the reversal portion 224b of the reversal plate 224 is separated from the contact surface 333a, whereas when the internal pressure of the cell case 200 is equal to or greater than the predetermined pressure, the reversal portion 224b contacts the contact surface 333a.

[0042] 5, the inverted portion 224b in the inverted shape has a bent portion 224b2 that is bent so as to be convex downward. The contact surface 333a is preferably formed at a position on the upper surface of the inverted portion 224b that contacts a region between the bent portion 224b2 and a portion of the second length L2 extending inward from the bent portion 224b2 in a direction parallel to the width direction. The second length L2 is half the length L1 between the bent portion 224b2 and the central axis L of the inverted portion 224b in a direction parallel to the width direction.

[0043] The insulating plate 340 is fixed to the upper surface of the lid 220. The insulating plate 340 holds the negative electrode terminal plate 330. The insulating plate 340 provides insulation between the lid 220 and the negative electrode terminal plate 330. A through hole for inserting a negative electrode connecting pin 420N described below is formed in each of the negative electrode terminal plate 330 and the insulating plate 340. As shown in Figs. 3 and 4, the insulating plate 340 has an exposure opening 342 that exposes the facing portion 332.

[0044] The connecting member 400 connects the plurality of tabs 110P, 110N to the external terminal 300. The connecting member 400 has a current collecting plate 410 and a connecting pin 420.

[0045] The current collector 410 is connected to a plurality of tabs. The current collector 410 includes a positive current collector 410P and a negative current collector 410N.

[0046] The positive electrode current collector 410P is connected to the multiple positive electrode tabs 110P by welding, etc. The positive electrode current collector 410P has a first flat plate portion 411 and a second flat plate portion 412.

[0047] A plurality of positive electrode tabs 110P are connected to the first flat plate portion 411 by ultrasonic welding or the like. Through holes are formed in the first flat plate portion 411. The plurality of positive electrode tabs 110P are connected to the lower surface of the first flat plate portion 411. However, the plurality of positive electrode tabs 110P may be connected to the upper surface of the first flat plate portion 411.

[0048] The second flat plate portion 412 is disposed on the outer side of the first flat plate portion 411 in the width direction. A connecting hole 412h and a fuse portion 412a are formed in the second flat plate portion 412. The fuse portion 412a is configured as a through hole that penetrates the second flat plate portion 412 in the thickness direction. As shown in FIG. 3, a thin portion may be formed between the second flat plate portion 412 and the first flat plate portion 411.

[0049] The negative current collector 410N is connected to a plurality of negative electrode tabs 110N by welding, etc. The configuration of the negative current collector 410N is substantially the same as the configuration of the positive current collector 410P.

[0050] The connecting pins 420 connect the current collecting plate 410 and the external terminal 300. The connecting pins 420 have a positive electrode connecting pin 420P and a negative electrode connecting pin 420N.

[0051] The positive electrode connecting pin 420P connects the positive electrode current collector plate 410P and the positive electrode terminal plate 310. The positive electrode connecting pin 420P is formed in a cylindrical shape. The lower end of the positive electrode connecting pin 420P is connected to the second flat plate portion 412 in a state where it is inserted into the connecting hole 412h. The upper end of the positive electrode connecting pin 420P is crimped to the positive electrode terminal plate 310.

[0052] The negative electrode connecting pin 420N connects the negative electrode current collector plate 410N and the negative electrode terminal plate 330. The negative electrode connecting pin 420N is formed in a cylindrical shape. The lower end of the negative electrode connecting pin 420N is connected to the second flat plate portion 412 in a state where it is inserted into the connecting hole 412h. The upper end of the negative electrode connecting pin 420N is crimped to the negative electrode terminal plate 330.

[0053] The insulating member 500 provides insulation between the connecting member 400 and the cell casing 200. The insulating member 500 includes an insulating sheet 510 and an insulator 520.

[0054] The insulating sheet 510 is connected to the lower surface of the lid main body 222. Through holes are formed in the insulating sheet 510 at a portion overlapping the pressure release valve 222a in the height direction, a portion overlapping the liquid injection hole 222b, a portion overlapping each pin insertion hole 222d, and a portion overlapping the reversal plate 224.

[0055] The insulator 520 has a shape that surrounds the connecting pin 420, and provides insulation between the connecting pin 420 and the cell case 200. The insulator 520 has a positive electrode side insulator 520P and a negative electrode side insulator 520N.

[0056] The positive electrode side insulator 520P covers the positive electrode connecting pin 420P. The positive electrode side insulator 520P is formed in a cylindrical shape. The positive electrode side insulator 520P insulates between the positive electrode connecting pin 420P and the lid main body 222.

[0057] The negative electrode side insulator 520N covers the negative electrode connecting pin 420N. The structure of the negative electrode side insulator 520N is the same as the structure of the positive electrode side insulator 520P.

[0058] In the energy storage cell 1 described above, when the internal pressure of the cell case 200 rises to or above the predetermined pressure due to the occurrence of an abnormality in the electrode assembly 100, as shown in FIG. 5, the inverted portion 224b of the inverted plate 224 inverts (deforms from a normal shape to an inverted shape) and comes into contact with the contact surface 333a of the negative electrode terminal plate 330. As a result, the external terminal 300, the connecting member 400, and the electrode assembly 100 form a closed circuit via the lid 220, and a large current flows through this circuit. Then, the fuse portion 412a formed in the second flat plate portion 412 melts. As a result, the electrical connection between the electrode assembly 100 and the cell case 200 is interrupted.

[0059] Here, when the reversible plate 224 is inverted (deformed from a normal shape to an inverted shape), as shown in FIG. 5, the regulating portion 226 abuts against the receiving portion 223, thereby suppressing the deformation of the reversible plate 224 from the inverted shape to the normal shape, i.e., the reversal of the reversible plate 224.

[0060] Modifications to the above embodiment will now be described.

[0061] (First Modification) As shown in FIGS. 6 and 7, the leg portions 226b of the restricting portion 226 have a shape that gradually inclines outward in the width direction as it extends downward from the fixing portion 226a.

[0062] (Second Modification) 8 and 9, the restricting portion 226 further has a protrusion 226c protruding downward from the outer edge of the leg portion 226b. The receiving portion 223 has a base 223a facing the protrusion 226c, and a standing wall 223b standing from the inner end of the base 223a and facing the leg portion 226b. This modification is also applicable to the restricting portion 226 in the above embodiment.

[0063] (Third Modification) As shown in FIGS. 10 and 11, the contact surface 333a of the protrusion 333 has a shape that contacts the entire upper surface of the inverted portion 224b in the inverted shape, the upper surface being located on the inside of the bent portion 224b2.

[0064] (Fourth Modification) As shown in FIGS. 12 and 13, the negative electrode terminal plate 330 does not have a protruding portion 333, and a contact surface 333a is formed on the facing portion 332.

[0065] Second embodiment Next, a storage cell 1 according to a second embodiment of the present disclosure will be described with reference to Fig. 14 and Fig. 15. Note that in the second embodiment, only the parts different from the first embodiment will be described, and the description of the same structure, action, and effect as the first embodiment will not be repeated.

[0066] The energy storage cell 1 in this embodiment further includes an inner insulator 610 and an outer insulator 620.

[0067] The inner insulator 610 is disposed inside the cell case 200. More specifically, the inner insulator 610 is disposed between the electrode assembly 100 and the current collector plate 410. The positive electrode tab 110P and the negative electrode tab 110N are connected to the current collector plate 410 above the inner insulator 610. A through hole is formed in the inner insulator 610 at a portion that overlaps with the through hole of the first flat plate portion 411 in the height direction. In this embodiment, as shown in FIG. 15, the electrode assembly 100 has four unit electrode bodies 111 to 114.

[0068] The outer insulator 620 is disposed on the outside of the cell casing 200. More specifically, the outer insulator 620 is disposed on the upper surface of the lid 220. Through holes are formed in the outer insulator 620 at a portion overlapping with the positive electrode member 300P in the height direction, a portion overlapping with the negative electrode member 300N, a portion overlapping with the pressure release valve 222a, and a portion overlapping with the liquid injection hole 222b.

[0069] 15, the insulating member 500 further has a pair of side sheets 511 connected to the insulating sheet 510. Each of the pair of side sheets 511 has a shape that extends downward from an edge of the insulating sheet 510 in the thickness direction. The pair of side sheets 511 are disposed between the sides of the electrode body 100 and the case body 210.

[0070] As shown in Figs. 14 and 15, the negative electrode member 300N further includes an insulating plate 350. The negative electrode terminal plate 330 includes a terminal block 331 and a conductive plate 335. The conductive plate 335 is fixed on an insulating plate 340, and the terminal block 331 is connected to the conductive plate 335 by welding or the like. A through hole is formed in each of the conductive plate 335 and the terminal block 331 for inserting the negative electrode connecting pin 420N therethrough. The conductive plate 335 includes a facing portion 332. The insulating plate 350 covers a portion of the conductive plate 335 located above the reversal plate 224.

[0071] It will be appreciated by those skilled in the art that the exemplary embodiments described above are examples of the following aspects.

[0072] [Aspect 1] An electrode body; A cell case that accommodates the electrode assembly; an external terminal fixed to an upper surface of the cell case; The cell casing comprises: a case body that houses the electrode body and has an opening that opens upward; a lid connected to the case body so as to close the opening of the case body, The lid is A lid body connected to the opening of the case body and charged to the positive or negative electrode of the electrode body; an inversion plate connected to the lid body and capable of short-circuiting the lid body and the external terminal; A regulating portion connected to the reversing plate, the reversible plate is deformable between a normal shape in which the reversible plate is curved so as to be convex in a direction away from the external terminal and an inverted shape in which the reversible plate is curved so as to be convex toward the external terminal and in contact with the external terminal, the lid body has a receiving portion that receives the restricting portion when the reversal plate is in the inverted shape, The receiving portion allows the inversion plate to pass through the regulating portion when the inversion plate deforms from the normal shape to the inverted shape, and abuts against the regulating portion when the inversion plate is in the inverted shape, thereby regulating the deformation of the inversion plate in the inverted shape toward the normal shape.

[0073] In this energy storage cell, when the reversal plate is inverted (deformed from a normal shape to an inverted shape), the regulating portion abuts against the receiving portion, thereby suppressing the deformation of the reversal plate from the inverted shape to the normal shape, i.e., suppressing reversal of the reversal plate.

[0074] [Aspect 2] The regulating portion is A fixing portion fixed to a lower surface of the reversal plate; A leg portion extending from the fixing portion and facing the receiving portion; a protrusion protruding downward from an outer edge of the leg, The receiving portion is a base facing the protrusion; 2. The storage cell of claim 1, further comprising: an upstanding wall that stands from an inner end of the base and faces the leg.

[0075] In this embodiment, the projection and the standing wall are engaged with each other, so that the deformation of the inversion plate from the inverted shape to the normal shape is more reliably suppressed.

[0076] [Aspect 3] 3. The energy storage cell according to claim 1, wherein the external terminal has a contact surface having a shape that follows an outer shape of the inversion plate in the inverted shape.

[0077] In this embodiment, the contact area between the reversal plate and the external terminal is ensured, so that the contact resistance between the reversal plate and the external terminal is reduced, thereby suppressing heat generation in the reversal plate when current is applied to the reversal plate.

[0078] [Aspect 4] A method for short-circuiting between the lid and the external terminal in an electricity storage cell comprising: an electrode body, a cell case that accommodates the electrode body, and an external terminal fixed to an upper surface of the cell case, the cell case having a case body that accommodates the electrode body and has an opening that opens upward, and a lid connected to the case body so as to close the opening of the case body, the lid being connected to the opening of the case body and having a lid body charged with a positive electrode or a negative electrode of the electrode body, a reversal plate connected to the lid body and capable of short-circuiting the lid body and the external terminal, and a restricting portion connected to the reversal plate, the lid body having a receiving portion that receives the restricting portion, A method for short-circuiting between a lid and an external terminal, when the internal pressure of the cell case reaches or exceeds a predetermined pressure, the reversal plate is inverted and passed through the receiving portion by the regulating portion, and the contact state of the reversal plate with the external terminal is maintained by abutting the regulating portion against the receiving portion while the reversal plate is in contact with the external terminal.

[0079] It should be noted that the embodiments disclosed herein are illustrative in all respects and should not be considered as limiting. The scope of the present invention is indicated by the claims, not by the description of the embodiments above, and further includes all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0080] 1 storage cell, 100 electrode body, 110N negative electrode tab, 110P positive electrode tab, 111, 112 unit electrode body, 120 insulating film, 200 cell case, 210 case body, 211 opening, 220 lid, 222 lid body, 223 receiving portion, 223a base, 223b standing wall, 224 inversion plate, 224a base, 224b inversion portion, 226 regulating portion, 226a fixing portion, 226b leg portion, 226c protrusion, 300 external terminal, 300N negative electrode member, 300P positive electrode member, 310 positive electrode terminal plate, 320 terminal block, 330 negative electrode terminal plate, 332 opposing portion, 333 protruding portion, 333a contact surface, 340 insulating plate, 400 Connecting member, 410 current collecting plate, 410N negative electrode current collecting plate, 410P positive electrode current collecting plate, 420 connecting pin, 420N negative electrode connecting pin, 420P positive electrode connecting pin, 422 coating portion, 422a fuse portion, 500 insulating member, 510 insulating sheet, 520 insulator, 520N negative electrode side insulator, 520P positive electrode side insulator.

Claims

1. An electrode body; A cell case that accommodates the electrode assembly; an external terminal fixed to an upper surface of the cell case; The cell casing comprises: The case body and A lid connected to the case body, The lid is A lid body connected to the case body and charged to the positive or negative electrode of the electrode body; an inversion plate connected to the lid body and capable of short-circuiting the lid body and the external terminal; A regulating portion connected to the reversing plate, the inversion plate is deformable between a normal shape in which the inversion plate is spaced apart from the external terminal and an inverted shape in which the inversion plate is in contact with the external terminal; the lid body has a receiving portion that receives the restricting portion when the reversal plate is in the inverted shape, The receiving portion allows the regulating portion to pass when the reversible plate is deformed into the inverted shape, and abuts against the regulating portion when the reversible plate is in the inverted shape, The regulating portion is A fixing portion fixed to a lower surface of the reversal plate; A leg portion extending from the fixing portion and facing the receiving portion; a protrusion protruding downward from an outer edge of the leg, The receiving portion is a base facing the protrusion; a wall rising from an inner end of the base and facing the leg portion.

2. a cell case that houses the electrode body, and an external terminal fixed to an upper surface of the cell case, the cell case having a case body and a lid connected to the case body, the lid having a lid body connected to the case body and charged with a positive electrode or a negative electrode of the electrode body, a reversal plate connected to the lid body and capable of short-circuiting the lid body and the external terminal, and a regulating portion connected to the reversal plate, the lid body having a receiving portion that receives the regulating portion, the regulating portion having a fixing portion fixed to a lower surface of the reversal plate, a leg portion extending from the fixing portion and facing the receiving portion, and a protrusion protruding downward from an outer edge of the leg portion, the receiving portion having a base facing the protrusion, and a standing wall that stands up from an inner end of the base and faces the leg portion, A method for short-circuiting between a lid and an external terminal, when the internal pressure of the cell case reaches or exceeds a predetermined pressure, the reversal plate is inverted and the receiving portion is passed through the regulating portion, and while the reversal plate is in contact with the external terminal, the leg portion of the regulating portion is opposed to the upright wall and the protrusion is opposed to the base, thereby maintaining the contact state of the reversal plate with the external terminal.

Images