Electric energy storage device

Abstract

To provide a power storage device with improved rigidity.SOLUTION: A power storage device comprises: a plurality of power storage elements 1 aligned in a first direction X; a pair of extension members 31, extending in the first direction, which sandwich the plurality of power storage elements from both sides in a second direction Y perpendicular to the first direction; and adjacent members 21, 22, and 23 each of which is disposed between adjacent ones of the plurality of power storage elements and is fixed to the pair of extension members. Each of the adjacent members comprises: a body member 5 which spreads between the adjacent ones of the power storage elements; and a connection member 6 which extends from one of the pair of extension members to the other one of the pair of extension members so as to penetrate the body member, and which connects the pair of extension members to each other. The connection member has a shape formed integrally with the body member.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a power storage device including a plurality of power storage elements arranged in a predetermined direction, a frame that sandwiches the plurality of power storage elements in a direction orthogonal to the arrangement direction of the power storage elements, and an adjacent member disposed between the power storage elements and fixed to the frame.

Background Art

[0002] Conventionally, a battery system including a plurality of power storage elements arranged in a first direction and a connecting bar (extension member) arranged along the plurality of power storage elements is known (see, for example, Patent Document 1). Specifically, as shown in FIG. 7, this battery system includes a plurality of stacked battery cells 102, a pair of end plates 140 disposed at both ends of the plurality of battery cells 102, and connecting bars 143 disposed on both side surfaces of the plurality of battery cells 102. The connecting bar 143 is in a strip shape, and bent pieces provided by bending both ends of the connecting bar 143 in a predetermined direction inward are fixed to the end plate 140. Thereby, the plurality of battery cells 102 are fixed in a stacked state.

[0003] By the way, in recent years, due to the increase in the energy density of power storage devices, the number of power storage elements arranged in power storage devices has increased, and the dimensions of power storage devices in the stacking direction of power storage elements tend to increase. Therefore, it has been necessary to further improve the rigidity of power storage devices.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Therefore, an object of the present embodiment is to provide a power storage device with improved rigidity.

Means for Solving the Problems

[0006] The power storage device of this embodiment includes a plurality of power storage elements arranged in a first direction, a pair of extending members each extending in the first direction and sandwiching the plurality of power storage elements from both sides in a second direction orthogonal to the first direction, and an adjacent member disposed between adjacent power storage elements among the plurality of power storage elements and fixed to the pair of extending members. The adjacent member includes a main body member that spreads between the adjacent power storage elements, and a connecting member that extends from one of the pair of extending members to the other of the pair of extending members, penetrates the main body member, and connects the pair of extending members. The connecting member has a shape that is integral with the main body member.

[0007] According to such a configuration, the adjacent member, that is, the connecting member extending from one extending member to the other extending member and the main body member integrated with this connecting member connect the pair of extending members, thereby improving the rigidity of the power storage device.

[0008] In the power storage device, the adjacent member has a nut, the connecting member extends in the second direction, so that at least one end projects outside the extending member in a state of penetrating the extending member, at least one end has a male screw with which the nut engages, at least a part of the connecting member in the second direction at a portion where the connecting member penetrates the main body member may have a non-circular periphery of a cross-section orthogonal to the second direction.

[0009] According to such a configuration, since at least a part of the cross-section of the connecting member at the portion where the connecting member penetrates the main body member has a non-circular shape, the rotation of the connecting member when fitting the nut onto the screw of the connecting member can be restricted.

[0010] In the power storage device, The portion of the connecting member that penetrates through the main body member may have a portion with a different cross-sectional area or cross-sectional shape from other portions in a part of the second direction.

[0011] According to such a configuration, the displacement of the connecting member in the second direction with respect to the main body member can be restricted due to the difference in the cross-sectional area or the cross-sectional shape of the connecting member.

Advantages of the Invention

[0012] According to the power storage device of the present embodiment, a power storage device with improved rigidity can be provided.

Brief Description of the Drawings

[0013]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Modes for Carrying Out the Invention

[0014] Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 to 6. Note that the names of the constituent members (each constituent element) of the present embodiment are those in the present embodiment and may be different from the names of the constituent members (each constituent element) in the background art.

[0015] As shown in FIG. 1, the power storage device includes a plurality of power storage elements 1 arranged in a first direction, a pair of extending members 31 each extending in the first direction and sandwiching the plurality of power storage elements 1 from both sides in a second direction orthogonal to the first direction, and an adjacent member 2 adjacent to the power storage element 10 in the first direction.

[0016] Furthermore, this power storage device includes a holding member 3 that holds the power storage element 1 and the adjacent member 2 together, and the extending member 31 is a part of this holding member 3. The holding member 3 is formed of a conductive material. Also, the power storage device includes an insulator 4 disposed between the power storage element 1 and the holding member 3.

[0017] In the following description, for convenience, each direction is described using a rectangular coordinate system including the X-axis direction, Y-axis direction, and Z-axis direction. The direction in which the power storage elements 1 are aligned (the first direction) is referred to as the X-axis direction. Also, one of the two-axis directions orthogonal to the direction in which the power storage elements 1 are aligned (the X-axis direction) (the second direction) is referred to as the Y-axis direction, and the remaining one direction (the third direction) is referred to as the Z-axis direction. Accordingly, in each drawing, orthogonal three axes (coordinate axes) corresponding to the X-axis direction, Y-axis direction, and Z-axis direction are supplementarily illustrated.

[0018] As shown in FIG. 2, the power storage element 1 includes an electrode body including a positive electrode and a negative electrode, a case 10 that houses the electrode body, and a pair of external terminals 11 disposed on the outer surface of the case 10. The power storage element 1 has a rectangular shape.

[0019] The case 10 has a case body 100 having an opening and a cover plate 101 that closes the opening of the case body 100, and the pair of external terminals 11 are disposed on the outer surface of the cover plate 101.

[0020] The case body 100 includes a closing portion 100a and a cylindrical body portion 100b connected to the periphery of the closing portion 100a so as to surround the closing portion 100a. The body portion 100b of the present embodiment is in the shape of a flat rectangular cylinder.

[0021] The body portion 100b includes a pair of first walls 100c that face each other with a space therebetween, and a pair of second walls 100d that face each other with the pair of first walls 100c interposed therebetween.

[0022] Each of the first wall 100c and the second wall 100d is formed in a rectangular shape. The body portion 100b is formed in a square tube shape. One end of the body portion 100b is closed by a closing portion 100a. In contrast, the other end of the body portion 100b is open and is closed by a cover plate 101.

[0023] Each of the plurality of power storage elements 1 is aligned in the X-axis direction (see FIG. 1). In the present embodiment, each of the plurality of power storage elements 1 is aligned with the first wall 100c of the case 10 facing in the X-axis direction. The power storage device includes a bus bar that electrically connects the external terminals 11 of two adjacent power storage elements 1.

[0024] The adjacent member 2 has insulation and is disposed between power storage elements 1 arranged in the X-axis direction or between a power storage element 1 and a member arranged in the X-axis direction with respect to the power storage element 1 (a part of the holding member 3 in the example of the present embodiment). The adjacent member 2 of the present embodiment is made of an insulating resin.

[0025] The power storage device has a plurality of adjacent members 2. In the present embodiment, the plurality of power storage elements 1 and the plurality of adjacent members 2 are alternately arranged in the first direction, and a flow path through which a temperature-adjusting fluid can flow is formed between an adjacent power storage element 1 and an adjacent member 2.

[0026] This adjacent member 2 includes a plurality of types of adjacent members. The adjacent member 2 in this embodiment includes a first adjacent member 21 disposed between the power storage elements 1, a second adjacent member 22 disposed between the power storage elements 1 and fixed to a pair of extension members 31, and a third adjacent member 23 adjacent to the power storage element 1 outside the power storage element 1 at the outermost end in the X-axis direction. That is, the power storage device includes, as the adjacent member 2, a first adjacent member 21, a second adjacent member 22, and a third adjacent member 23. The power storage device in 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 1 except for the pair of power storage elements 1 between which the second adjacent member 22 is disposed.

[0027] The second adjacent member 22 is disposed between adjacent power storage elements 1 among the plurality of power storage elements 1 and is fixed to a pair of extension members 31. Further, as shown in FIG. 3, the second adjacent member 22 includes a main body member 5 that extends between adjacent power storage elements 1 and a connecting member 6 that connects the pair of extension members 31 to each other. Furthermore, the second adjacent member 22 has a fastening member (for engaging) for fastening the second adjacent member 22 to the pair of extension members 31. The fastening member in this embodiment is, for example, a nut 7. Also, the second adjacent member 22 in this embodiment is disposed at the central position in the X-axis direction in the power storage device.

[0028] The second adjacent member 22 in this embodiment includes two connecting members 6. Also, this second adjacent member 22 includes four fastening members (nuts 7 in this embodiment).

[0029] The material of the main body member 5 is, for example, a resin such as polypropylene. Also, the connecting member 6 is made of metal. The second adjacent member 22 is integrally molded. For example, with the connecting member 6 incorporated in a mold, the main body member 5 is formed in a state of being integrated with the connecting member 6 by filling the resin.

[0030] The main body member 5 is a member that faces a part of the first wall 100c of the case 10 of the power storage element 1 in a state of being in contact therewith.

[0031] Specifically, the main body member 5 has a rectangular shape corresponding to the adjacent power storage element 1 as viewed from the X-axis direction, and is, for example, in the shape of a rectangular plate.

[0032] More specifically, the main body member 5 has two opposing surfaces 52 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 element 1 (the first wall 100c of the case 10), and a plurality of ridges 53 protruding from each opposing surface 52. Thereby, the main body member 5 forms a flow path through which a temperature-adjusting fluid can flow between the adjacent power storage elements 1 in cooperation with the adjacent power storage element 1.

[0033] The ridges 53 are longitudinally extended in the Y-axis direction. The plurality of ridges 53 are arranged at equal intervals in the Z-axis direction.

[0034] Further, the main body member 5 has an arrangement region 51 where the connection member 6 is arranged. The main body member 5 of the present embodiment has a plurality of arrangement regions 51.

[0035] The plurality of arrangement regions 51 are arranged side by side at intervals in the Z-axis direction on the end surface 50 in the Y-axis direction of the main body member 5. In the main body member 5 of the present embodiment, two arrangement regions 51 are arranged at intervals in the Z-axis direction. Each arrangement region 51 is a columnar space. Further, the arrangement region 51 extends along the Y-axis direction. Each arrangement region 51 of the present embodiment extends in the Y-axis direction between the end surfaces 50 in the Y-axis direction of the main body member 5.

[0036] For example, as shown in FIG. 5, each arrangement region 51 has a plurality of regions that extend in the Y-axis direction and have different cross-sectional areas or cross-sectional shapes. More specifically, each arrangement region 51 has a first region 511 that is a columnar space extending in the Y-axis direction, a second region 512 that is a space extending in the Y-axis direction and having a non-circular cross-sectional shape, and a third region 513 that is a columnar space extending in the Y-axis direction and having a smaller cross-sectional area than the first region.

[0037] The connecting member 6 is a member that connects the pair of extending members 31 by being fixed to the pair of extending members 31 by fastening, welding, etc. (see Fig. 3). Further, the connecting member 6 extends from one of the pair of extending members 31A to the other of the pair of extending members 31B among the pair of extending members 31 and penetrates the main body member 5. Furthermore, the connecting member 6 has a shape that is integral with the main body member 5. Note that the rigidity of the connecting member 6 is higher than that of the main body member 5.

[0038] The two connecting members 6 are arranged, for example, at both ends in the Z-axis direction of the main body member 5. In the present embodiment, each connecting member 6 is arranged in an arrangement region 51 provided in the main body member 5.

[0039] The connecting member 6 is surrounded by the resin of the main body member 5 so that the arrangement region 51 of the main body member 5 has a shape corresponding to the connecting member 6 (see Fig. 5). That is, the connecting member 6 is arranged in the arrangement region 51 of the main body member 5 without a gap.

[0040] For example, the connecting member 6 is a columnar member. The connecting member 6 extends along the Y-axis direction. In the present embodiment, the connecting member 6 is a substantially columnar shape extending in the Y-axis direction. Specifically, the connecting member 6 is a metal rod whose dimension in the Y-axis direction is at least longer than the dimension of the main body member 5 in the Y-axis direction.

[0041] In the present embodiment, by extending in the Y-axis direction, the connecting member 6 projects at least one end portion 60 outside the extending member 31 in a state of penetrating the extending member 31 (one of the extending members 31A or the other extending member 31B) (see Fig. 1). Specifically, by extending in the Y-axis direction, the connecting member 6 projects both end portions 60 outside the pair of extending members 31.

[0042] Further, at least one end portion 60 of the connecting member 6 has an engaged portion with which a fastening member or the like engages or is screwed, etc. as shown in Fig. 4. This engaged portion is, for example, a male screw with which the nut 7 engages. Specifically, both end portions 60 of the connecting member 6 have male screws with which the nut 7 engages.

[0043] Furthermore, the connecting member 6 has a main body portion 61 that connects both end portions 60. The portion (main body portion 61) that penetrates the main body member 5 of the connecting member 6 has a portion (first portion 62) with a different cross-sectional area or cross-sectional shape from other portions (second portion 63 and third portion 64) in a part of the Y-axis direction. In the present embodiment, the cross-sectional shape is different between the first portion 62 and the second portion 63 and the third portion 64 (the portions other than the first portion 62 of the main body portion 61).

[0044] In the present embodiment, the connecting member 6 has a plurality of (for example, three) first portions 62. The first portions 62 are respectively arranged at an intermediate position (for example, the central position) in the Y-axis direction of the main body portion 61 and both side positions sandwiching this intermediate position. The first portions 62 adjacent to each other in the Y-axis direction are arranged at equal intervals. Further, the contour of the cross-section of the first portion 62 is circular.

[0045] Also, in the present embodiment, in at least a part (in the present embodiment, the second portion 63) in the Y-axis direction of the portion (main body portion 61) that penetrates the main body member 5 of the connecting member 6, the periphery (contour of the cross-section) of the cross-section orthogonal to the Y-axis direction is non-circular (a shape having irregularities) as shown in FIG. 6. The connecting member 6 has a plurality of (for example, two) second portions 63. The second portions 63 are arranged over substantially the entire main body portion 61 (see FIG. 4). Specifically, the second portion 63 is separated by the first portion 62. Note that the second portion 63 is not formed at both end portions 60 (the portions protruding from the main body member 5) of the connecting member 6.

[0046] The contour of the cross-section of the second portion 63 is a shape provided with at least one convex portion 630 protruding radially outward from the circumference, for example, a shape provided with a plurality of convex portions 630 (see FIG. 6). Note that in the present embodiment, the contour of the cross-section of the second portion 63 is the same at any portion in the Y-axis direction.

[0047] Specifically, the plurality of convex portions 630 are arranged side by side in the circumferential direction, for example. Further, the convex portions 630 are arranged at equal intervals in the circumferential direction. Note that the cross-sectional shapes of the respective convex portions 630 are all the same. Also, the convex portions 630 are ridges 630 extending in the Y-axis direction (see FIG. 4). Further, the circumferential positions of the respective convex portions 630 are the same on both sides of the first portion 62 located in the middle of the Y-axis direction.

[0048] In the present embodiment, the connecting member 6 has a plurality of (for example, two) third portions 64. The third portions 64 are respectively arranged at both ends of the main body portion 61. Also, the third portions 64 are arranged at positions sandwiching the second portion 63 together with the first portion 62 in the Y-axis direction. Further, the contour of the cross-section of the third portion 64 is circular.

[0049] The nut 7 is a member for fixing the connecting member 6 to the extending member 31 (see FIG. 3). The nut 7 is arranged at a position sandwiching one of the extending members 31A or the other extending member 31B together with the main body member 5. The nut 7 is, for example, a nut for fixing the end portion 60 of the connecting member 6 to the extending member 31. In the present embodiment, the male screw of the end portion 60 of the connecting member 6 passing through the pair of extending members 31 engages (is screwed) with the nut, whereby the main body member 5 is fixed to the holding member 3.

[0050] In the present embodiment, each of the extending members 31 is sandwiched between each end portion 60 of the connecting member 6 and the nut 7. Also, in the present embodiment, since the connecting member 6 is configured not to come off from the main body member 5 in the Y-axis direction, one of the extending members 31A, the main body member 5, and the other extending member 31B are sandwiched between each end portion 60 of the connecting member 6 and the nut 7 engaged with each end portion 60, whereby the pair of extending members 31 are fixed to the second adjacent member 22.

[0051] Each of the plurality of first adjacent members 21 has a first main body portion that extends in a direction orthogonal to the X-axis direction between adjacent power storage elements 1 in the X-axis direction, and an outer peripheral portion of the first main body portion (in this embodiment, the four corners of the rectangular plate-shaped first main body portion) that extends in the X-axis direction and at least one first restricting portion that restricts the movement of the adjacent power storage element 1 with respect to the first main body portion. Further, each of the plurality of first adjacent members 21 forms at least one flow path through which a temperature-adjusting fluid can flow between the adjacent power storage elements 1. Note that the thickness of the first main body portion of the first adjacent member 21 in the X-axis direction is, for example, thinner than the thickness of the main body member 5 of the second adjacent member 22 in the X-axis direction.

[0052] Each of the two third adjacent members 23 has a third main body portion that extends in a direction orthogonal to the X-axis direction between the adjacent power storage element 1 and the holding member 3 (specifically, the end member 30), and an outer peripheral portion of the third main body portion (in this embodiment, the four corners of the rectangular plate-shaped third main body portion) that extends in the X-axis direction and at least one third restricting portion that restricts the movement of the adjacent power storage element 1 with respect to the third main body portion. Further, each of the two third adjacent members 23 forms at least one flow path through which a temperature-adjusting fluid can flow between the adjacent power storage elements 1.

[0053] In this embodiment, the holding member 3 is made of metal. The holding member 3 includes a pair of end members 30 disposed at respective positions adjacent to each of the third adjacent members 23, and a pair of extension members 31 connecting each of the pair of end members 30.

[0054] Each of the pair of end members 30 has a first surface facing the third adjacent member 23 and a second surface opposite to the first surface. Each of the pair of end members 30 abuts against the third adjacent member 23.

[0055] The end member 30 is made of metal. Further, the end member 30 has a shape corresponding to the power storage element 1 when viewed from the X-axis direction.

[0056] Each extension member 31 has connection portions 310, 311 extending between a pair of end members 30. In the present embodiment, the pair of extension members 31 each have a first connection portion 310 extending in the X-axis direction at a position corresponding to one end portion of the plurality of power storage elements 1 in the Z-axis direction, a second connection portion 311 extending in the X-axis direction at a position corresponding to the other end portion of the plurality of power storage elements 1 in the Z-axis direction, and a plurality of reinforcing portions 312 extending in the Z-axis direction and connecting the first connection portion 310 and the second connection portion 311. In the present embodiment, the pair of extension members 31 are in a frame shape (frame-like), but may have other shapes such as bar shape (strip-like) or plate shape (plate-like).

[0057] The first connection portion 310 and the second connection portion 311 are arranged at intervals in the Z-axis direction. Each of the first connection portion 310 and the second connection portion 311 has a first end and a second end opposite to the first end in the longitudinal direction.

[0058] Also, each of the first connection portion 310 and the second connection portion 311 is bent along the longitudinal direction. In each of the first connection portions 310, one portion with the bent portion as a boundary is arranged at a position corresponding to the cover plate 101 or the closing portion 100a of the power storage element 1. In each of the first connection portion 310 and the second connection portion 311, the other with the bent portion as a boundary is arranged at a position corresponding to the second wall 100d of the power storage element 1.

[0059] The plurality of reinforcing portions 312 are arranged at intervals in the X-axis direction. In the present embodiment, the plurality of reinforcing portions 312 include a pair of first reinforcing portions 313 connecting the ends of the first connection portion 310 and the second connection portion 311 arranged at intervals in the Z-axis direction, and a plurality (seven in the example of the present embodiment) of second reinforcing portions 314 connecting the regions excluding the ends of the first connection portion 310 and the second connection portion 311 arranged at intervals in the Z-axis direction.

[0060] The first reinforcing portion 313 is connected to the end member 30.

[0061] The second reinforcing part 314 is provided with a through hole 314a through which the connecting member 6 is inserted. In the present embodiment, the through hole 314a is provided in the second reinforcing part 314 disposed at the central position in the X-axis direction of the first connecting part 310 and the second connecting part 311. The number of through holes 314a provided is the same as the number of connecting members 6. More specifically, a pair of through holes 314a are provided in the second reinforcing part 314 and are disposed at each end in the Z-axis direction.

[0062] The insulator 4 has a shape corresponding to each extending member 31. Further, the insulator 4 is disposed between each extending member 31 and the plurality of power storage elements 1 to provide insulation between them.

[0063] According to the above power storage device, the second adjacent member 22, that is, the connecting member 6 extending from one extending member 31A to the other extending member 31B and the main body member 5 integrated with the connecting member 6 connect the pair of extending members 31 to each other, thereby improving the rigidity of the power storage device.

[0064] In the power storage device of the present embodiment, since at least a part of the cross section of the portion (main body portion 61) of the connecting member 6 passing through the main body member 5 has a non-circular shape, the rotation of the connecting member 6 with the extending direction as the axial direction is restricted, so that the rotation of the connecting member 6 when fitting the nut 7 onto the screws provided at both ends 60 of the connecting member 6 can be restricted. Specifically, at least a part of the main body portion 61 of the connecting member 6 has a non-circular cross section, and the main body member 5 surrounds the connecting member 6 (the second portion 63 which is the portion having a non-circular cross section) without a gap, so that the rotation of the connecting member 6 can be restricted. More specifically, by fitting the nut 7 onto the screws provided at both ends 60 of the connecting member 6, the rotation of the connecting member 6 when connecting the connecting member 6 to the pair of extending members 31 can be restricted.

[0065] Further, in the power storage device of the present embodiment, the displacement in the Y-axis direction of the pair of extension members 31 of the connection member 6 can be restricted by the difference in the cross-sectional area or the difference in the cross-sectional shape of the connection member 6 (in this embodiment, the cross-sectional shape of the first portion 62). Specifically, the main body portion 61 of the connection member 6 has portions with different cross-sectional areas and cross-sectional shapes, and the main body member 5 surrounds the connection member 6 (the portions with different cross-sectional areas and cross-sectional shapes of the connection member 6) without a gap, thereby restricting the disengagement of the connection member 6 in the Y-axis direction.

[0066] Note that the power storage device according to 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.

[0067] For example, the second adjacent member 22 is not limited to the configuration of the above embodiment. The second adjacent member 22 may include one connection member 6 or three or more connection members 6. Note that the fastening members (for example, nuts 7 that are screwed onto the male threads at the end portions 60) that engage with the end portions 60 of the connection member 6 may be provided in a number corresponding to the engaging portions of the end portions 60 of the connection member 6.

[0068] The second adjacent member 22 may not include the nut 7. In this case, the connection member 6 may not be provided with male threads at both end portions 60 of the connection member 6, and the both end portions 60 may be fixed by welding to the pair of extension members 31, respectively.

[0069] The connection member 6 may be a bar having a circular cross-sectional shape. Specifically, the entire periphery of the cross-section may be circular in the Y-axis direction of the main body portion 61. Further, the main body portion 61 may have the same cross-sectional area and cross-sectional shape throughout the Y-axis direction.

[0070] Furthermore, the connecting member 6 only needs to extend from one extension member 31A to the other extension member 31B and penetrate the main body member 5, and it may be a member with an overall prismatic shape or a columnar member with a bent middle part in the Y-axis direction. Also, the connecting member 6 may be, for example, a strip-shaped member extending in the Y-axis direction. Furthermore, the connecting member 6 may be a member with a plate-shaped middle part in the Y-axis direction and columnar both ends in the Y-axis direction.

[0071] Note that the connecting member 6 may be configured such that the middle parts of the two connecting members 6 in the Y-axis direction are connected by a part extending in the Z-axis direction.

[0072] Furthermore, male threads may be provided only at one end 60 of the connecting member 6. In this case, the end 60 provided with male threads may be fixed to the extension member 31 with a nut 7, and the end 60 not provided with male threads may be fixed to the extension member 31 by welding.

[0073] Also, in the connecting member 6, the cross-sectional area may be different between the first part 62 and the part other than the first part 62 of the main body part 61 (for example, the second part 63). That is, when the main body part 61 is substantially columnar, the diameter of the first part 62 and the diameter of the part other than the first part 62 of the main body part 61 (for example, the second part 63) may be different.

[0074] Also, the second adjacent member 22 may be arranged at a position other than the intermediate position in the X-axis direction of the power storage device. Furthermore, the power storage device may include a plurality of second adjacent members 22.

Explanation of Reference Numerals

[0075] 1... Storage element, 2... Adjacent member, 3... Holding member, 4... Insulator, 5... Body member, 6... Connecting member, 7... Nut, 10... Case, 11... External terminal, 21... First adjacent member, 22... Second adjacent member, 23... Third adjacent member, 30... End member, 31... Extension member, 31A... One extension member, 31B... The other extension member, 50... End face, 51... Arrangement region, 52... Opposing face, 53... Ridge, 60... End portion, 61... Body portion, 62... First portion, 63... Second portion, 64... Third portion, 100... Case body, 100a... Closing portion, 100b... Barrel portion, 100c... First wall, 100d... Second wall, 101... Cover plate, 102... Battery cell, 140... End plate, 143... Connecting bar, 310... First connection portion (connection portion), 311... Second connection portion (connection portion), 312... Reinforcement portion, 313... First reinforcement portion, 314... Second reinforcement portion, 314a... Through hole, 511... First region, 512... Second region, 513... Third region, 630... Protrusion (ridge)

Claims

1. A plurality of power storage elements arranged in a first direction; A pair of extending members each extending in the first direction and sandwiching the plurality of power storage elements from both sides in a second direction orthogonal to the first direction; An adjacent member disposed between adjacent ones of the plurality of power storage elements and fixed to the pair of extending members. The adjacent member includes a main body member that spreads between the adjacent power storage elements, a connecting member that extends from one of the pair of extending members to the other of the pair of extending members and penetrates the main body member, and connects the pair of extending members, and a nut. The connecting member has a shape integral with the main body member and extends in the second direction, so that at least one end projects outside the extending member in a state of penetrating the extending member. At least one end has a male screw with which the nut engages. A power storage device, characterized in that a periphery of a cross section orthogonal to the second direction is non-circular at least in a part in the second direction of a part of the connecting member penetrating the main body member.

2. The power storage device according to claim 1, characterized in that a part of the connecting member penetrating the main body member has a part different in cross-sectional area or cross-sectional shape from other parts in a part of the second direction.

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