Electric energy storage device

Abstract

To provide a power storage device in which termination members are hardly deformed.SOLUTION: A power storage device comprises: a plurality of power storage elements 10 arranged in a first direction; a pair of termination members 41 which sandwich the plurality of power storage elements from the outside in the first direction; at least two first connection parts 421, namely 421A, which extend in the first direction along the plurality of power storage elements and connect the pair of termination members together; and a second connection part 422, namely 422A, which extends in the first direction along the plurality of power storage elements. Each of the plurality of power storage elements has an external terminal 14 on one end in a second direction perpendicular to the first direction. At least the two first connection parts connect ends, of the termination members, in a third direction perpendicular to the first direction and the second direction, or ends in the third direction at the end in the second direction of the termination members. The second connection part connects portions, of the termination members, at middle positions in the third direction at the end in the second direction.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a power storage device in which a plurality of power storage elements are held by a holding member.

Background Art

[0002] Conventionally, a battery block in which a plurality of battery cells are stacked via a separator has been known (see Patent Document 1). This battery block is a block body in which a plurality of battery cells are stacked via an insulating separator, and end plates are arranged on both sides in the stacking direction. The end plates are connected by a binding bar. This binding bar is arranged on both side surfaces of the battery block, and both end portions thereof are bent inward, and the bent portions are fixed to the end plates with set screws.

[0003] In the power storage device configured as described above, since only the side end portions of the end plates are connected by the binding bar, when each battery cell swells due to aging deterioration or the like, the central portion in the width direction of each end plate, that is, the portion between the end portions where the binding bar is fixed with set screws is deformed (curved) so as to bulge outward in the stacking direction.

[0004] As described above, when the end plate is deformed, high stress is generated in the binding bar, the connection portion between the end plate and the binding bar, etc., and the binding bar and the end plate may be damaged due to this high stress.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] Therefore, an object of the present embodiment is to provide a power storage device in which the end member is difficult to deform.

Means for Solving the Problem

[0007] The power storage device of this embodiment includes a plurality of power storage elements arranged in a first direction, a pair of end members that sandwich the plurality of power storage elements from the outside in the first direction, at least two first connection parts that extend in the first direction along the plurality of power storage elements and connect the pair of end members, a second connection part that extends in the first direction along the plurality of power storage elements, and is provided with each of the plurality of power storage elements has an external terminal at one end in a second direction orthogonal to the first direction, the at least two first connection parts connect the ends of each end member in a third direction orthogonal to each of the first direction and the second direction, or the ends of each end member in the third direction at the ends in the second direction, the second connection part connects the parts at intermediate positions in the third direction at the ends of each end member in the second direction.

[0008] According to such a configuration, in addition to the pair of end members being connected by at least two first connection parts at the ends in the second direction and the like, the second connection part connects the parts at intermediate positions in the third direction at the ends of each end member in the second direction. Therefore, even if each power storage element in the power storage device tries to swell, the deformation of each end member can be suppressed, that is, the end member is difficult to deform.

[0009] In the power storage device, it includes a frame having two of the first connection parts, the second connection part, and a pair of extension parts extending in the third direction, in this frame, the two first connection parts connect the ends of each end member in the third direction at one end in the second direction, the second connection part connects the parts at intermediate positions in the third direction at the one end in the second direction of each end member, The pair of extension portions may extend in the third direction at one end of each of the end members in the second direction, and connect the corresponding ends of the two first connection portions and the second connection portion in the first direction, respectively.

[0010] In this way, in the frame, since the ends of the two first connection portions and the second connection portion in the first direction are connected by a pair of extension portions, the rigidity of the power storage device is increased.

[0011] In this case, the power storage device includes a pair of the frames. These pair of frames may be arranged at the ends in the second direction with respect to the pair of end members.

[0012] In this way, in the power storage device, since the frames are respectively arranged at the ends in the second direction, the rigidity of the power storage device is further increased.

[0013] Also, in the power storage device, Each external terminal of the plurality of power storage elements may be arranged in a region surrounded by the first connection portion, the second connection portion, and the pair of extension portions when viewed from the second direction.

[0014] In this way, since the external terminals of each power storage element are arranged in the region surrounded by the first connection portion, the second connection portion, and the pair of extension portions, the frame does not get in the way during operations on the external terminals such as attaching a bus bar to the external terminals.

[0015] Also, in the power storage device, Each of the plurality of power storage elements has a gas discharge valve at one end in the second direction. The second connection portion may be arranged at a position overlapping the gas discharge valve of each power storage element when viewed from the one side in the second direction.

[0016] By arranging the second connection portion in this manner, it is possible to suppress the scattering of the gas in the second direction when the gas is discharged from the gas discharge valve, or to use it for attaching to a power storage device such as a duct member for guiding the gas.

Advantages of the Invention

[0017] As described above, according to the present embodiment, it is possible to provide a power storage device in which the terminal member is difficult to deform.

Brief Description of the Drawings

[0018]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Modes for Carrying Out the Invention

[0019] Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 to 5. Note that the names of the respective constituent members (each constituent element) of the present embodiment are those in the present embodiment, and may be different from the names of the respective constituent members (each constituent element) in the background art.

[0020] As shown in FIGS. 1 to 4, the power storage device includes a plurality of power storage elements 10 arranged in a predetermined direction (first direction) and a holding member 4 that holds the plurality of power storage elements 10. Further, the power storage device 1 includes a plurality of adjacent members 2 adjacent to the power storage elements 10 in the predetermined direction, and the power storage elements 10 and the adjacent members 2 are alternately arranged in the predetermined direction. The power storage device 1 also includes at least one insulator 6 disposed between the plurality of power storage elements 10 and the holding member 4, and a plurality of bus bars 8 that connect different power storage elements 10 in a conductive manner.

[0021] Each of the plurality of power storage elements 10 is a primary battery, a secondary battery, a capacitor, or the like. The power storage element 10 of the present embodiment is a rechargeable non-aqueous electrolyte secondary battery. More specifically, the power storage element 10 is a lithium-ion secondary battery that utilizes electron transfer generated by the movement of lithium ions. Each of these plurality of power storage elements 10 has an external terminal 14 at one end in a direction (second direction) orthogonal to the predetermined direction.

[0022] Specifically, each power storage element 10 includes an electrode body, a case 13 that houses the electrode body together with an electrolytic solution, an external terminal 14 at least a part of which is exposed outside the case 13 or an external terminal constituted by a part of the case 13, and a current collector that connects the electrode body and the external terminal 14. The power storage element 10 of the present embodiment includes two external terminals 14 at least a part of which is exposed outside the case 13.

[0023] In the electrode body, a positive electrode and a negative electrode are alternately laminated with a separator therebetween. In this electrode body, lithium ions move between the positive electrode and the negative electrode, whereby the power storage element 10 is charged and discharged.

[0024] The case 13 has a case body 131 having an opening and a plate-shaped cover plate 132 that closes (seals) the opening of the case body 131.

[0025] The case body 131 includes a plate-shaped closing portion 1311 and a cylindrical body portion (peripheral wall) 1312 connected to the periphery of the closing portion 1311.

[0026] The closing portion 1311 is a part that is located at the lower end of the case body 131 when the case body 131 is arranged with the opening facing upward (i.e., it is the bottom wall of the case body 131 when the said opening faces upward). The closing portion 1311 is rectangular when viewed from the normal direction of the closing portion 1311.

[0027] The body portion 1312 has a rectangular tube shape, more specifically, a flat rectangular tube shape. The body portion 1312 has a pair of long wall portions 1313 extending from the long sides at the periphery of the closing portion 1311 and a pair of short wall portions 1314 extending from the short sides at the periphery of the closing portion 1311. That is, the pair of long wall portions 1313 face each other with a space therebetween in the Y-axis direction (specifically, a space corresponding to the short side at the periphery of the closing portion 1311), and the pair of short wall portions 1314 face each other with a space therebetween in the X-axis direction (specifically, a space corresponding to the long side at the periphery of the closing portion 1311). By connecting the corresponding (specifically, facing each other in the Y-axis direction) ends of the pair of long wall portions 1313 with the short wall portions 1314 respectively, the rectangular tube-shaped body portion 1312 is formed.

[0028] As described above, the case body 131 has a rectangular tube shape (i.e., a bottomed rectangular tube shape) with one end in the opening direction (Z-axis direction) blocked.

[0029] The cover plate 132 is a plate-shaped member that closes the opening of the case body 131. The cover plate 132 of this embodiment is a rectangular plate material that is long in the X-axis direction when viewed from the Z-axis direction. This cover plate 132 has its peripheral portion overlapped with the peripheral portion of the opening of the case body 131 so as to close the opening of the case body 131. This cover plate 132 has a gas discharge valve 132a that can discharge the gas inside the case 13 to the outside.

[0030] The gas discharge valve 132a discharges gas from inside the case 13 to the outside when the internal pressure of the case 13 rises to a predetermined pressure. The gas discharge valve 132a of the present embodiment is provided at the central portion in the longitudinal direction of the cover plate 132. Specifically, the gas discharge valve 132a has a thin-walled portion in which a break groove is formed. When the internal pressure (gas pressure) of the case 13 becomes larger than a predetermined value, the thin-walled portion of the gas discharge valve 132a tears from the break groove, thereby communicating the inside (internal space) and the outside (external space) of the case 13. Thereby, the gas discharge valve 132a discharges the gas inside the case 13 to the outside and reduces the increased internal pressure of the case 13.

[0031] The two external terminals 14 are arranged at both ends in the longitudinal direction of the cover plate 132. That is, the two external terminals 14 are arranged on the cover plate 132 such that the gas discharge valve 132a is positioned therebetween. Each of these two external terminals 14 is a part that is electrically connected to the external terminal 14 of another power storage element 10 or an external device, etc., and is formed of a conductive member. For example, the external terminal 14 is formed of a highly weldable metal material such as an aluminum-based metal material such as aluminum or an aluminum alloy, or a copper-based metal material such as copper or a copper alloy.

[0032] Each power storage element 10 is configured as described above, and a plurality of power storage elements 10 are arranged in the predetermined direction with the long wall portions 1313 of the case 13 (case body 131) facing each other.

[0033] In the following description, the direction (first direction) in which a plurality of power storage elements 10 are arranged is the X-axis direction of the rectangular coordinate system, the direction (third direction) in which a pair of narrow-width surfaces (wall portions) of the case 13 face each other is the Y-axis direction of the rectangular coordinate system, and the normal direction (second direction) of the cover plate 132 is the Z-axis direction of the rectangular coordinate system.

[0034] The adjacent member 2 has insulation properties and is disposed between the power storage elements 10 arranged in the X-axis direction or between the power storage element 10 and a member (a part of the holding member 4 in the example of this embodiment) arranged in the X-axis direction with respect to the power storage element 10. The adjacent member 2 of this embodiment is made of resin having insulation properties. As described above, this adjacent member 2 forms a flow path R through which a temperature-adjusting fluid such as air can flow between the adjacent power storage elements 10.

[0035] This adjacent member 2 includes a plurality of types of adjacent members. The adjacent member 2 of this embodiment includes a first adjacent member 21 disposed between the power storage elements 10, a second adjacent member 22 disposed between the power storage elements 10 and fixed to the holding member 4, and a third adjacent member 23 adjacent to the outermost power storage element 10 in the X-axis direction and adjacent to the power storage element 10. That is, the power storage device 1 includes the first adjacent member 21, the second adjacent member 22, and the third adjacent member 23 as the adjacent member 2. The power storage device 1 of this embodiment includes a plurality of first adjacent members 21, one second adjacent member 22, and two (a pair of) third adjacent members 23. Each of these plurality of first adjacent members 21 is disposed between each pair of power storage elements 10 excluding the pair of power storage elements 10 between which the second adjacent member 22 is disposed.

[0036] Each of the plurality of first adjacent members 21 has a first main body portion 211 that extends in a direction orthogonal to the X-axis direction between the power storage elements 10 adjacent in the X-axis direction, and at least one first restricting portion 215 that restricts the movement of the adjacent power storage element 10 with respect to the first main body portion 211. Further, each of the plurality of first adjacent members 21 forms at least one flow path R through which a temperature-adjusting fluid can flow between the adjacent power storage elements 10.

[0037] The first main body portion 211 is a portion that faces a wide surface of the case 13 of the power storage element 10 in a state of being in partial contact therewith. This first main body portion 211, in cooperation with an adjacent power storage element 10, forms a flow path R through which a fluid for temperature adjustment can flow between the first main body portion 211 and the power storage element 10. The first main body portion 211 of the present embodiment is in the shape of a rectangular plate having a size corresponding to the power storage element 10 when viewed in the X-axis direction, and has a rectangular wave shape in a cross-sectional shape along the X-Z plane (a plane including the X-axis direction and the Z-axis direction).

[0038] The first restricting portion 215 extends in the X-axis direction from at least a corner portion of the rectangular first main body portion 211, and abuts against the power storage element 10 (specifically, the case 13) adjacent to the first main body portion 211 from the outside in the Y-Z plane direction (a plane including the Y-axis direction and the Z-axis direction), thereby restricting the relative movement of the power storage element 10 with respect to the first main body portion 211 in the Y-Z plane direction. The first restricting portion 215 of the present embodiment extends from the first main body portion 211 toward both sides in the X-axis direction.

[0039] The second adjacent member (adjacent member) 22 has a second main body portion 221 that extends in a direction orthogonal to the X-axis direction between power storage elements 10 adjacent in the X-axis direction, and at least one second restricting portion 225 that restricts the movement of the power storage element 10 adjacent to the second main body portion 221 with respect to the second main body portion 221. Further, the second adjacent member 22 forms at least one flow path R through which a fluid for temperature adjustment can flow between adjacent power storage elements 10. The second adjacent member 22 of the present embodiment is disposed at the central position in the X-axis direction in the power storage device 1.

[0040] The second main body portion 221 is a portion that faces a wide surface of the case 13 of the power storage element 10 in a state of being in partial contact therewith. This second main body portion 221 also, similar to the first main body portion 211 of the first adjacent member 21, forms a flow path R through which a fluid for temperature adjustment can flow between the adjacent power storage elements 10 in cooperation with the adjacent power storage elements 10. The second main body portion 221 of the present embodiment forms a plurality of flow paths R between adjacent power storage elements 10. Specifically, the second main body portion 221 forms a plurality of flow paths R between the power storage element 10 adjacent to one side in the X-axis direction and the second main body portion 221, and also forms a plurality of flow paths R between the power storage element 10 adjacent to the other side in the X-axis direction and the second main body portion 221.

[0041] Specifically, as shown in FIG. 5, the second main body portion 221 has a rectangular shape corresponding to the adjacent power storage element 10 as viewed from the X-axis direction, and is a thick plate shape having a dimension in the X-axis direction (thickness dimension) larger than that of the first main body portion 211.

[0042] More specifically, the second main body portion 221 has two opposing surfaces 2211 that extend in a direction orthogonal to the X-axis direction at each of one end and the other end in the X-axis direction and face the adjacent power storage elements 10 (the wide surfaces of the case 13), and a plurality of ridges 2212 protruding from each of the opposing surfaces 2211. The second main body portion 221 has fixing portions 224 for fixing the second main body portion 221 to the holding member 4 at each end surface 2213 in the Z-axis direction. The second main body portion 221 of the present embodiment has a plurality of fixing portions 224 at each end surface 2213 in the Z-axis direction.

[0043] On each of the opposing surfaces 2211, each of the plurality of ridges 2212 extends in the Y-axis direction and is arranged at intervals in the Z-axis direction. Each of the plurality of ridges 2212 abuts the tip in the protruding direction (X-axis direction) against the power storage element 10 adjacent to the second main body portion 221. Thereby, a plurality of flow paths R are formed between the adjacent power storage elements 10.

[0044] The plurality of fixing portions 224 are arranged side by side at intervals in the Y-axis direction on the end surface 2213 in the Z-axis direction of the second main body portion 221. On each end surface 2213 in the Z-axis direction of the second main body portion 221 of the present embodiment, two fixing portions 224 are arranged at intervals in the Y-axis direction. More specifically, the two fixing portions 224 are arranged at each end in the Y direction on the end surface 2213. Each fixing portion 224 of the present embodiment is an insert nut, and the second main body portion 221 is fixed to the holding member 4 by engaging (threading) a connecting member N such as a screw that passes through the holding member 4 with the insert nut.

[0045] The second restricting portion 225 extends in the X-axis direction from at least a corner portion (the corner portion when viewed from the X-axis direction) of the rectangular second main body portion 221, and abuts against the power storage element 10 (specifically, the case 13) adjacent to the second main body portion 221 from the outside in the Y-Z plane direction, thereby restricting the relative movement of the power storage element 10 in the Y-Z plane direction with respect to the second main body portion 221. The second restricting portion 225 of the present embodiment extends from both sides in the X-axis direction of the second main body portion 221, respectively.

[0046] Each of the two third adjacent members 23 has a third main body portion 231 that extends in a direction orthogonal to the X-axis direction between the power storage element 10 adjacent in the X-axis direction and the holding member 4 (specifically, the end member 41), and at least one third restricting portion 235 that restricts the movement of the adjacent power storage element 10 with respect to the third main body portion 231. In addition, each of the two third adjacent members 23 forms at least one flow path R through which a temperature-adjusting fluid can flow between the adjacent power storage elements 10.

[0047] The third main body portion 231 is a portion that faces a wide surface of the case 13 of the power storage element 10 in a state of being in partial contact. Similar to the first main body portion 211 of the first adjacent member 21 and the second main body portion 221 of the second adjacent member 22, the third main body portion 231 also forms a flow path R through which a temperature-adjusting fluid can flow between the adjacent power storage elements 10 in cooperation with the adjacent power storage element 10. The third main body portion 231 of the present embodiment forms a plurality of flow paths R between the adjacent power storage elements 10.

[0048] Specifically, the third main body portion 231 is in the shape of a rectangular plate having a size corresponding to the adjacent power storage element 10 when viewed from the X-axis direction. More specifically, the third main body portion 231 extends in a direction orthogonal to the X-axis direction at each of one end and the other end in the X-axis direction, and has two opposing surfaces 2311 that face the adjacent power storage element 10 (the wide surface of the case 13) or the end member 41, and a plurality of ridges 2312 that protrude from the opposing surface 2311 on the power storage element 10 side.

[0049] On the opposing surface 2311 on the side of the energy storage element 10, each of the plurality of ridges 2312 extends in the Y-axis direction and is arranged at intervals in the Z-axis direction. Each of the plurality of ridges 2312 abuts the energy storage element 10 adjacent to the third main body 231 at the tip in the protruding direction (X-axis direction). As a result, a flow path R is formed on the side of the third main body 231 facing the energy storage element 10 by the opposing surface 2311 on the side of the energy storage element 10, two ridges 2312 adjacent to each other at intervals in the Z-axis direction on the opposing surface 2311, and the energy storage element 10 (case 13) facing the opposing surface 2311.

[0050] The third restricting portion 235 extends in the X-axis direction from at least a corner portion of the rectangular third main body 231 and abuts the energy storage element 10 (specifically, the case 13) adjacent to the third main body 231 from the outside in the Y-Z plane direction to restrict the relative movement of the energy storage element 10 in the Y-Z plane direction with respect to the third main body 231. The third restricting portion 235 of the present embodiment extends from the third main body 231 toward one side (the side of the energy storage element 10) in the X-axis direction.

[0051] The holding member 4 holds the plurality of energy storage elements 10 and the plurality of adjacent members 2 together by surrounding the periphery of the plurality of energy storage elements 10 and the plurality of adjacent members 2. The holding member 4 is made of metal. Specifically, the holding member 4 includes a pair of end members 41 that sandwich the plurality of energy storage elements 10 from the outside in the X-axis direction, a pair of frames 42 that connect the pair of end members 41, and a plurality of connecting members 43 that connect the end members 41 and the frames 42.

[0052] Each of the pair of end members 41 is arranged so as to sandwich a third adjacent member 23 between itself and the energy storage element 10 arranged at the end (the outermost) in the X-axis direction. Each of the pair of end members 41 is a rectangular plate-shaped member having a size corresponding to the energy storage element 10 when viewed from the X-axis direction, and the rigidity of each end member 41 is higher than that of the third adjacent member 23. Each end member 41 has a plurality of through holes 411 arranged at intervals in the Y-axis direction at both ends in the Z-axis direction. Each end member 41 of the present embodiment has three through holes 411 at one end in the Z-axis direction and three through holes 411 at the other end.

[0053] The three through holes 411 on one side in the Z-axis direction include a through hole (first through hole) 411a with different positions in the Z-axis direction. This first through hole 411a is a through hole arranged at the center in the Y-axis direction and is located on one side in the Z-axis direction from the remaining two through holes (second through holes) 411b. These two second through holes 411b are arranged at both ends in the Y-axis direction.

[0054] Also, the three through holes 411 on the other side in the Z-axis direction have the same positions in the Z-axis direction and are arranged at equal intervals in the Y-axis direction. That is, the three through holes 411 are arranged at both ends in the Y-axis direction and at the center in the Y-axis direction.

[0055] Each of the pair of frames 42 has two side connection parts (first connection parts) 421, one intermediate connection part (second connection part) 422, and a pair of extension parts 423. These pair of frames 42 are arranged at each end in the Z-axis direction with respect to the pair of end members 41. Hereinafter, the frame 42 on one side in the Z-axis direction may also be referred to as the first frame 42A, and the frame 42 on the other side in the Z-axis direction may also be referred to as the second frame 42B.

[0056] The first frame 42A has two first side connection parts 421A that extend in the X-axis direction and are arranged at intervals in the Y-axis direction, a first intermediate connection part 422A that extends in the X-axis direction and is arranged between the two first side connection parts 421A in the Y-axis direction, and a pair of first extension parts 423A that extend in the Y-axis direction and connect the two first side connection parts 421A and the first intermediate connection part 422A.

[0057] The two first side connection parts 421A are parts that connect the respective ends in the Y-axis direction at one end in the Z-axis direction of each end member 41. Each of these two first side connection parts 421A extends in the X-axis direction along a plurality of power storage elements 10 at the end in the Y-axis direction.

[0058] Specifically, each first side connection portion 421A is a long portion having a cross-sectional shape bent along a corner portion (the corner portion of the case 13) formed by the cover plate 132 and the short wall portion 1314 of the power storage element 10. Specifically, it has a plate-like first portion 4211A extending in the X-axis direction along the cover plate 132 of each power storage element 10, and a plate-like second portion 4212A extending in the X-axis direction along the short wall portion 1314 of each power storage element 10.

[0059] In the first side connection portion 421A of the present embodiment, the width at each position in the X-axis direction of the first portion 4211A is constant, and the width at each position in the X-axis direction of the second portion 4212A is constant.

[0060] Also, each first side connection portion 421A has a fixing piece 4214 for fixing the second adjacent member. This fixing piece 4214 is a plate-like portion extending from the central portion in the X-axis direction of the first portion 4211A toward the inside in the Y-axis direction, and has a through hole 4214a penetrating in the Z-axis direction. The fixing piece 4214 of the present embodiment extends along the end face 2213 in the Z-axis direction of the second adjacent member 22, and the through hole 4214a is arranged at a position overlapping with the fixing portion (insert nut in the example of the present embodiment) 224 of the second adjacent member 22 when viewed from the Z-axis direction.

[0061] The first intermediate connection portion 422A is a portion that connects the portions at intermediate positions in the Y-axis direction at one end in the Z-axis direction of each terminal member 41. This first intermediate connection portion 422A is arranged at a position overlapping with the gas discharge valve 132a of each power storage element 10 when viewed from one side in the Z-axis direction. Specifically, the first intermediate connection portion 422A is a strip-shaped portion having a constant width dimension in the Y-axis direction at each position in the X-axis direction. The first intermediate connection portion 422A of the present embodiment extends from one end to the other end in the X-axis direction at the central position in the Y-axis direction of the power storage device 1, and the width dimension (dimension in the Y-axis direction) is larger than that of the gas discharge valve 132a. In the power storage device 1 of the present embodiment, when gas is discharged from the gas discharge valve 132a of the power storage element 10, it is discharged from the end in the X-axis direction through the space between the first intermediate connection portion 422A and each power storage element 10.

[0062] A pair of first extension parts 423A extend in the Y-axis direction at one end of each end member 41 in the Z-axis direction, and connect the corresponding ends in the X-axis direction of two first side connection parts 421A and a first intermediate connection part 422A respectively.

[0063] Specifically, each first extension part 423A has a first part 4231A of the extension part that extends in the Y-axis direction from one first side connection part 421A to the other first side connection part 421A along one edge of the end member 41 in a state of facing the edge in the Z-axis direction, and a second part 4232A of the extension part that extends in the Z-axis direction (towards the second frame 42B side) along the outer surface of the end member 41 from the outer end in the X-axis direction of the first part 4231A of the extension part.

[0064] The width in the X-axis direction at each position in the Y-axis direction of the first part 4231A of the extension part is constant. Also, the second part 4232A of the extension part extends to the other side in the Z-axis direction from the entire region in the Y-axis direction of the first part 4231A of the extension part. That is, the second part 4232A of the extension part extends from the second part 4212A of one first side connection part 421A to the second part 4212A of the other first side connection part 421A.

[0065] This second part 4232A of the extension part has through holes 4233A at positions corresponding to the respective through holes 411 on one side in the Z-axis direction of the end member 41. That is, the second part 4232A of the extension part has a plurality (three in the example of this embodiment) of through holes 4233A. The second part 4232A of this embodiment has a first through hole 4233A1 at a position corresponding to the first through hole 411a of the end member 41, and two second through holes 4233A2 at positions corresponding to the two second through holes 411b of the end member 41. And in the second part 4232A of the extension part, similar to the respective through holes 411a, 411b of the end member 41, the first through hole 4233A1 is a through hole arranged at the center in the Y-axis direction, and is located on one side in the Z-axis direction from the remaining two second through holes 4233A2. Thereby, in the second part 4232A of the extension part, the portion where the second through holes 4233A2 are formed at both ends in the Y-axis direction has a larger dimension in the Z-axis direction than the portion where the first through hole 4233A1 is formed at the center in the Y-axis direction, that is, it extends to the other side in the Z-axis direction.

[0066] The second frame 42B has two second side connection parts 421B that extend in the X-axis direction and are spaced apart in the Y-axis direction, a second intermediate connection part 422B that extends in the X-axis direction and is disposed between the two second side connection parts 421B in the Y-axis direction, and a pair of second extension parts 423B that extend in the Y-axis direction and connect the two second side connection parts 421B and the second intermediate connection part 422B. Further, the second frame 42B has a plurality of intermediate extension parts 424B that extend in the Y-axis direction at an intermediate position in the X-axis direction.

[0067] The two second side connection parts 421B are parts that connect the respective end parts in the Y-axis direction at the other end parts of each end member 41 in the Z-axis direction. Each of these two second side connection parts 421B extends in the X-axis direction along the plurality of power storage elements 10 at the end parts in the Y-axis direction.

[0068] Specifically, each second side connection part 421B is an elongated part having a cross-sectional shape bent along a corner (a corner of the case 13) formed by the short wall part 1314 and the closing part 1311 of the power storage element 10. More specifically, it has a plate-like first part 4211B that extends in the X-axis direction along the closing part 1311 of each power storage element 10, and a plate-like second part 4212B that extends in the X-axis direction along the short wall part 1314 of each power storage element 10.

[0069] In the second side connection part 421B of the present embodiment, the width at each position in the X-axis direction of the first part 4211B is constant, and the width at each position in the X-axis direction of the second part 4212B is constant.

[0070] The second intermediate connection part 422B is a part that connects the parts at intermediate positions in the Y-axis direction at the other end parts of each end member 41 in the Z-axis direction. This second intermediate connection part 422B is a strip-shaped part having a constant width dimension in the Y-axis direction at each position in the X-axis direction. The second intermediate connection part 422B of the present embodiment extends from one end to the other end in the X-axis direction at the central position in the Y-axis direction of the power storage device 1.

[0071] A pair of second extension parts 423B extend in the Y-axis direction at the other end of each end member 41 in the Z-axis direction, and connect the corresponding ends in the X-axis direction of the two second side connection parts 421B and the second intermediate connection part 422B respectively.

[0072] Specifically, each second extension part 423B has a first part 4231B of the extension part that extends in the Y-axis direction from one second side connection part 421B to the other second side connection part 421B along the edge while facing the other edge of the end member 41 in the Z-axis direction, and a second part 4232B of the extension part that extends in one side (the first frame 42A side) in the Z-axis direction along the outer surface of the end member 41 from the outer end in the X-axis direction of the first part 4231B of the extension part.

[0073] The width in the X-axis direction at each position in the Y-axis direction of the first part 4231B of the extension part is constant. Also, the second part 4232B of the extension part extends to one side in the Z-axis direction from the entire region in the Y-axis direction of the first part 4231B of the extension part. That is, the second part 4232B of the extension part extends from the second part 4212B of one second side connection part 421B to the second part 4212B of the other second side connection part 421B.

[0074] This second part 4232B of the extension part has through holes 4233B at positions corresponding to the respective through holes 411 on the other side of the end member 41 in the Z-axis direction. That is, the second part 4232B of the extension part has a plurality (three in the example of this embodiment) of through holes 4233B. The positions of the respective through holes 4233B in the Z-axis direction are the same.

[0075] Each of the plurality of intermediate extension parts 424B extends in the Y-axis direction from one second side connection part 421B to the other second side connection part 421B. The plurality of intermediate extension parts 424B in this embodiment include a first intermediate extension part 4241B to which the second adjacent member 22 is fixed and a plurality of second intermediate extension parts 4242B.

[0076] The first intermediate extension portion 4241B extends in the Y-axis direction so as to connect the central portions in the X-axis direction of the respective second side portion connection portions 421B, and has at least one through hole 4241b in the Z-axis direction. The first intermediate extension portion 4241B of the present embodiment extends along the end face 2213 in the Z-axis direction of the second adjacent member 22, and the through hole 4241b is disposed at a position overlapping with the fixing portion (insert nut in the example of the present embodiment) 224 of the second adjacent member 22 when viewed from the Z-axis direction. That is, the first intermediate extension portion 4241B has two through holes 4241b.

[0077] Each of the plurality of second intermediate extension portions 4242B extends in the Y-axis direction between the second extension portion 423B and the first intermediate extension portion 4241B in the X-axis direction. In the second frame 42B of the present embodiment, one second intermediate extension portion 4242B is disposed between one second extension portion 423B and the first intermediate extension portion 4241B, and one second intermediate extension portion 4242B is disposed between the other second extension portion 423B and the first intermediate extension portion 4241B.

[0078] Each of the plurality of connecting members 43 connects the end member 41 and the frame 42 in a state where the through hole 411 of the end member 41 and the through holes 4233A and 4233B of the frame 42 are inserted therethrough. Each connecting member 43 of the present embodiment is composed of a bolt 431 and a nut 432.

[0079] The insulator 6 has insulation properties. This insulator 6 is disposed between the frame 42 and the plurality of power storage elements 10. Specifically, the power storage device 1 includes a pair of insulators 6, and each insulator 6 covers at least a region of the frame 42 facing the plurality of power storage elements 10.

[0080] Among the pair of insulators 6, the portions 61 corresponding to the fixing pieces 4214 in the insulator 6A on the first frame 42A side each have through holes 610 at positions corresponding to the through holes 4214a of the fixing pieces 4214. Further, among the pair of insulators 6, the portions 62 corresponding to the first intermediate extension portions 4241B in the insulator 6B on the second frame 42B side have through holes 620 at positions corresponding to the through holes 4241b of the first intermediate extension portions 4241B.

[0081] Each of the plurality of busbars 8 is a plate-like member having conductivity such as metal. Each busbar 8 electrically connects the external terminals 14 of the power storage elements 10 to each other. The plurality of busbars 8 in the present embodiment connect (electrically connect) the plurality of power storage elements 10 included in the power storage device 1 in series.

[0082] According to the above power storage device 1, in addition to the pair of end members 41 being connected to each other at the ends in the Z-axis direction by the side connection portions (first connection portions) 421A and 421B, the intermediate connection portions (second connection portions) 422A and 422B connect the portions at the intermediate positions in the Y-axis direction at the ends in the Z-axis direction of each end member 41 to each other. Therefore, even if each power storage element 10 in the power storage device 1 tries to expand, the deformation of each end member 41 is effectively suppressed, that is, the end member 41 is difficult to deform.

[0083] The power storage device 1 of the present embodiment includes a frame 42 having two side connection portions 421, an intermediate connection portion 422, and a pair of extension portions 423. In this frame 42, the ends of the two side connection portions 421 and the intermediate connection portion 422 in the X-axis direction are connected to each other by a pair of extension portions 423, thereby increasing the rigidity of the power storage device 1.

[0084] Further, the power storage device 1 of the present embodiment includes a pair of frames 42A and 42B, and these pair of frames 42A and 42B are arranged at the ends in the Z-axis direction with respect to the pair of end members 41. In this way, by arranging the frames 42A and 42B at the ends in the Z-axis direction in the power storage device 1, the rigidity of the power storage device 1 is further increased.

[0085] In the power storage device 1 of the present embodiment, each external terminal 14 of the plurality of power storage elements is disposed within a region surrounded by a first side connection portion 421A, a first intermediate connection portion 422A, and a pair of first extension portions 423A when viewed from the Z-axis direction. By disposing the external terminal 14 of each power storage element 10 within the region A (see FIG. 3) surrounded by the first side connection portion 421A, the first intermediate connection portion 422A, and the pair of first extension portions 423A in this manner, the frame does not interfere during operations on the external terminal such as attaching the bus bar 8 to the external terminal 14.

[0086] In the power storage device 1 of the present embodiment, the first intermediate connection portion 422A is disposed at a position overlapping with the gas discharge valve 132a of each power storage element 10 when viewed from one side in the Z-axis direction. By disposing the first intermediate connection portion 422A in this manner, it is possible to suppress the scattering of the gas in the Z-axis direction when the gas is discharged from the gas discharge valve 132a, or to use it for attaching a duct member or the like that guides the gas to the power storage device 1.

[0087] Note that the power storage device of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention. For example, the configuration of another embodiment can be added to the configuration of a certain embodiment, and a part of the configuration of a certain embodiment can be replaced with the configuration of another embodiment. Further, a part of the configuration of a certain embodiment can be deleted.

[0088] In the power storage device 1 of the above-described embodiment, the side connection portion 421, the intermediate connection portion 422, and the extension portion 423 are integrally formed to constitute the frame 42, but the present invention is not limited to this configuration. The side connection portion 421 and the intermediate connection portion 422 may be separate bodies (separate members).

[0089] In addition, in the power storage device 1 of the above embodiment, the side connection portion 421 connects the end portions in the Y-axis direction at the edges (end portions) in the Z-axis direction of each end member 41, but the configuration is not limited to this. The side connection portion 421 may be configured to connect the end portions in the Y-axis direction of each end member 41. In this case, for example, the first side connection portion 421A and the second side connection portion 421B may be integrally formed, and each intermediate connection portion 422A, 422B may be formed of independent members.

[0090] In addition, in the power storage device 1 of the above embodiment, the intermediate connection portion 422 is disposed at each end portion in the Z-axis direction of the end member 41, but the configuration is not limited to this. The intermediate connection portion 422 may be disposed only at one end portion in the Z-axis direction of the end member 41.

[0091] In addition, in the power storage device 1 of the above embodiment, one intermediate connection portion 422 is disposed at the end portion in the Z-axis direction of the end member 41, but the configuration is not limited to this. A plurality of intermediate connection portions 422 may be disposed at the end portion in the Z-axis direction of the end member 41.

[0092] In addition, in the power storage device 1 of the above embodiment, the intermediate connection portion 422 is disposed at the central position in the Y-axis direction, but the configuration is not limited to this. The intermediate connection portion 422 may be disposed at a position shifted from the central position in the Y-axis direction to one side or the other side.

[0093] In addition, in the power storage device 1 of the above embodiment, the first intermediate connection portion 422A is disposed at a position overlapping with the gas discharge valve 132a of each power storage element 10 when viewed from one side in the Z-axis direction, but the configuration is not limited to this. The first intermediate connection portion 422A may be disposed at a position not overlapping with the gas discharge valve 132a when viewed from one side in the Z-axis direction.

[0094] In the energy storage device 1 of the above-described embodiment, the first intermediate connection portion 422A is a strip-shaped portion extending in the X-axis direction, but is not limited to this configuration. For example, the first intermediate connection portion 422A may have through holes at respective positions corresponding to the gas discharge valves 132a of the respective energy storage elements 10 (positions overlapping when viewed from the Z-axis direction). According to such a configuration, since the gas discharged from the gas discharge valve 132a can pass through the first intermediate connection portion 422A in the Z-axis direction through the through hole corresponding to the gas discharge valve 132a, it becomes possible to dispose a member (such as a duct member) for guiding the gas on one side in the Z-axis direction of the first intermediate connection portion 422A (the side opposite to the energy storage element 10 side).

[0095] Further, the intermediate connection portion 422 is not limited to a strip shape, and may be a portion (or member) having a circular or square cross section or the like. That is, the intermediate connection portion 422 may be configured to extend in the X-axis direction and connect the portions at intermediate positions in the Y-axis direction at the Z-axis direction ends of the respective end members 41.

[0096] In the energy storage device 1 of the present embodiment, the connecting members 43 for connecting the side connection portion 421 or the intermediate connection portion 422 and the end member 41 are bolts 431 and nuts 432, but are not limited to this configuration. The connecting member 43 may be a rivet or the like. Further, the side connection portion 421 or the intermediate connection portion 422 and the end member 41 may be connected by welding or the like.

[0097] Further, the portion where the side connection portion 421 or the intermediate connection portion 422 and the end member 41 overlap in the X-axis direction is connected in a state where the connecting member 43 penetrates in the X-axis direction, but is not limited to this configuration. For example, the portion where the side connection portion 421 or the intermediate connection portion 422 and the end member 41 overlap in the Z-axis direction may be connected in a state where the connecting member 43 penetrates in the Z-axis direction.

[0098] In the energy storage device 1 of the above-described embodiment, the first frame 42A and the second frame 42B have different configurations, but are not limited to this configuration. The first frame 42A and the second frame 42B may have the same configuration.

[0099] Moreover, although the power storage device 1 of the above embodiment includes the second adjacent member 22, it is not limited to this configuration.

[0100] In addition, in the above embodiment, the case where the power storage element is used as a non-aqueous electrolyte secondary battery (for example, a lithium ion secondary battery) capable of charging and discharging has been described. However, the type and size (capacity) of the power storage element are arbitrary. Also, in the above embodiment, a lithium ion secondary battery has been described as an example of the power storage element, but it is not limited thereto. For example, the present invention is applicable to various secondary batteries, other primary batteries, and power storage elements of capacitors such as electric double layer capacitors.

Explanation of Reference Numerals

[0101] 1…Power storage device, 2…Adjacent member, 21…First adjacent member (adjacent member), 211…First main body part, 215…First restricting part, 22…Second adjacent member (adjacent member), 221…Second main body part, 2211…Opposing surface, 2212…Ridge, 2213…End face, 224…Fixing part, 225…Second restricting part, 23…Third adjacent member (adjacent member), 231…Third main body part, 2311…Opposing surface, 2312…Ridge, 235…Third restricting part, 4…Holding member, 41…Terminal member, 411…Through hole, 411a…First through hole, 411b…Second through hole, 42…Frame, 421…Side connection part (first connection part), 422…Intermediate connection part (second connection part), 423…Extension part, 42A…First frame (frame), 421A…First side connection part (first connection part), 4211A…First part, 4212A…Second part, 4213A…Third part, 4214…Fixing piece, 4214a…Through hole, 422A…First intermediate connection part (second connection part), 423A…First extension part (extension part), 4231A…First part of the extension part, 4232A…Second part of the extension part, 4233A…Through hole, 4233A1…First through hole, 4233A2…Second through hole, 42B…Second frame (frame), 421B…Second side connection part (first connection part), 4211B…First part, 4212B…Second part, 4213B…Third part, 422B…Second intermediate connection part (second connection part), 423B…Second extension part (extension part), 4231B…First part of the extension part, 4232B…Second part of the extension part, 4233B…Through hole, 424B…Intermediate extension part, 4241B…First intermediate extension part, 4241b…Through hole, 4242B…Second intermediate extension part, 43…Connecting member, 431…Bolt, 432…Nut, 6, 6A, 6B…Insulator, 61…Part corresponding to the fixing piece, 610…Through hole, 62…Part corresponding to the first intermediate extension part, 620…Through hole, 8…Bus bar, 10…Power storage element, 13…Case, 131…Case body, 1311…Blocking part, 1312…Barrel part, 1313…Long wall part, 1314…Short wall part, 132…Cover plate, 132a…Gas discharge valve, 14…External terminal, A…Region, N…Connecting member, R…Flow path

Claims

1. A plurality of power storage elements arranged in a first direction, A pair of end members sandwiching the plurality of power storage elements from the outside in the first direction, A pair of frames each having two first connection portions extending in the first direction along the plurality of power storage elements and connecting the pair of end members, a second connection portion extending in the first direction along the plurality of power storage elements, and a pair of extension portions, Each of the plurality of power storage elements has an external terminal at one end in a second direction orthogonal to the first direction, In the frame, The two first connection portions connect the respective end portions in a third direction orthogonal to each of the first direction and the second direction at one end in the second direction of each end member, The second connection portion connects the portions at intermediate positions in the third direction at one end in the second direction of each end member, The pair of extension portions extend in the third direction at one end in the second direction of each end member and connect the corresponding end portions in the first direction of the two first connection portions and the second connection portion, respectively, The pair of frames are arranged at the respective end portions in the second direction with respect to the pair of end members. A power storage device.

2. A plurality of power storage elements arranged in a first direction, A pair of end members sandwiching the plurality of power storage elements from the outside in the first direction, A frame having two first connection portions extending in the first direction along the plurality of power storage elements and connecting the pair of end members, a second connection portion extending in the first direction along the plurality of power storage elements, and a pair of extension portions, Each of the plurality of power storage elements has an external terminal at one end in a second direction orthogonal to the first direction, In the frame, The two first connection portions connect the respective end portions in a third direction orthogonal to each of the first direction and the second direction at one end in the second direction of each end member, The second connection portion connects the portions at intermediate positions in the third direction at one end in the second direction of each end member, The pair of extension portions extend in the third direction at one end in the second direction of each end member and connect the corresponding end portions in the first direction of the two first connection portions and the second connection portion, respectively, In the power storage device, each external terminal of the plurality of power storage elements is disposed within a region surrounded by the first connection portion, the second connection portion, and the pair of extension portions when viewed from the second direction.

3. Each of the plurality of power storage elements has a gas discharge valve at one end in the second direction, The power storage device according to claim 1 or 2, wherein the second connection portion is disposed at a position overlapping the gas discharge valve of each power storage element when viewed from the one side in the second direction.

4. A plurality of power storage elements arranged in a first direction; A pair of end members sandwiching the plurality of power storage elements from the outside in the first direction; At least two first connection portions extending in the first direction along the plurality of power storage elements and connecting the pair of end members; A second connection portion extending in the first direction along the plurality of power storage elements, and comprising: Each of the plurality of power storage elements has an external terminal at one end in a second direction orthogonal to the first direction, The at least two first connection portions connect end portions in a third direction orthogonal to each of the first direction and the second direction in each end member, or connect end portions in the third direction at the end portions in the second direction of each end member, The second connection portion connects portions at intermediate positions in the third direction at the end portions in the second direction of each end member, In the power storage device, portions extending in the second direction along the end member from both end portions in the first direction of each first connection portion are respectively fixed to the end member, and portions extending in the second direction along the end member from both end portions in the first direction of the second connection portion are respectively fixed to the end member.

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