Power storage device

Abstract

To provide a power storage device including an adjacent member reduced in thickness while securing the strength of a fixing site with an extension member.SOLUTION: A power storage device includes: a plurality of power storage elements aligned in a first direction; an extension member adjacent to the plurality of power storage elements in a second direction perpendicular to the first direction, the extension member extending in the first direction; and an adjacent member 2 disposed between adjacent two power storage elements and fixed to the extension member. The adjacent member includes: a second body 21B spreading in a direction perpendicular to the first direction between the power storage elements; and a second fastening member 22B disposed at an edge of the second body in the second direction, and used to fix the adjacent member to the extension member. The thickness dimension of a base 212B in the first direction is less than or equal to the thickness dimension of an arrangement site 211B, the base being a site other than the arrangement site where a fastening member of the body is arranged in a third direction perpendicular to each of the first direction and the second direction, and a base 212B1 has, at least part in the third direction, a thin site 213B with a thickness dimension smaller than that of the arrangement site.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to an energy storage device including a plurality of energy storage elements. [Background technology]

[0002] BACKGROUND ART Conventionally, a power storage module including a battery group in which a plurality of batteries are stacked horizontally has been known (see Patent Document 1).

[0003] In this energy storage module, as shown in Fig. 10, storage batteries 501 are rectangular and arranged in an upright position, stacked alternately with insulating separators 502 in the X-axis direction. Rectangular end plates 504 are arranged on both ends of the storage battery group in the stacking direction, with insulating end holders 503 interposed between them. The end plates 504 are connected to each other by a pair of restraining bands 505 arranged on both sides in the Y-axis direction and extending in the X-axis direction, clamping and holding the storage battery group together in the X-axis direction.

[0004] One or more intermediate plates 506 are arranged inside the storage battery group in the stacking direction. The intermediate plates 506 have the same shape as the storage batteries 501. Specifically, the intermediate plates 506 are configured by providing insert nuts on a plate-shaped resin plate of uniform thickness. As a result, a screw hole 507a and a pair of screw holes 507b are formed on both side surfaces of the intermediate plate 506, one above the other and one below the screw hole 507a.

[0005] The restraint band 505 has a flat surface 5051 that extends in the stacking direction parallel to the side surface of the battery pack. Near the center of the flat surface 5051 in the stacking direction, a hole 5052 is formed that is coaxial with the screw hole 507a formed in one side surface of the intermediate plate 506, and a pair of holes 5053 are formed that are coaxial with the pair of screw holes 507b. Bolts are inserted into the holes 5052, 5053 of the restraint band 505, and the bolts are screwed into the screw holes 507a, 507b formed in both side surfaces of the intermediate plate 506. In this way, the intermediate plate 506 is fixed to the restraint band 505.

[0006] In recent years, due to demands for smaller and lighter energy storage modules, there has been a demand for thinner components constituting the energy storage module 500 (reduced dimensions in the stacking direction), such as the intermediate plate 506 disposed between adjacent storage batteries 501 and fixed to the restraint band 505.

[0007] However, in the above-mentioned energy storage module 500, since the intermediate plate 506 is fixed to the restraint band 505, stress is easily applied to the fixed portion with the restraint band 505 due to expansion of the storage battery 501, etc., and as a result, the module is configured to be thick overall (so that the dimensions in the stacking direction are large) in order to ensure sufficient strength. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-122572 Summary of the Invention [Problem to be solved by the invention]

[0009] Therefore, an object of this embodiment is to provide an electricity storage device including an adjacent member that is thinned while ensuring the strength of the fixed portion with the extension member. [Means for solving the problem]

[0010] The power storage device of this embodiment is A plurality of storage elements arranged in a first direction; an extension member adjacent to the plurality of energy storage elements in a second direction perpendicular to the first direction and extending along the first direction; an adjacent member disposed between two adjacent storage elements and fixed to the extension member; The adjacent member is a main body portion extending in a direction perpendicular to the first direction between the energy storage elements; a fastening member disposed at an end of the main body portion in the second direction and used to fasten the adjacent member to the extension member; The thickness dimension in the first direction of the base, which is a portion of the main body other than the arrangement portion where the fastening member is arranged in a third direction perpendicular to each of the first direction and the second direction, is approximately the same as or less than the thickness dimension of the arrangement portion, and the base has a thin-walled portion in at least a part of the third direction that is thinner than the arrangement portion. [Effects of the Invention]

[0011] As described above, according to this embodiment, it is possible to provide an electricity storage device including an adjacent member that is thinned while ensuring the strength of the fixed portion with the extension member. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a perspective view of the electricity storage device according to this embodiment. [Figure 2] FIG. 2 is an exploded perspective view of the electricity storage device, with some of the components omitted. [Figure 3] FIG. 3 is a perspective view of a second adjacent member included in the electricity storage device. [Figure 4] FIG. 4 is a perspective view of the second adjacent member. [Figure 5] FIG. 5 is a view of the second adjacent member as viewed from the Y-axis direction. [Figure 6] FIG. 6 is a view of the second adjacent member as viewed from the X-axis direction. [Figure 7] FIG. 7 is a cross-sectional view taken along the line VII-VII in FIG. [Figure 8] FIG. 8 is a cross-sectional view taken along the line VIII-VIII in FIG. [Figure 9] FIG. 9 is a perspective view of a second adjacent member according to another embodiment. [Figure 10] FIG. 10 is an exploded perspective view of a conventional electricity storage module. DETAILED DESCRIPTION OF THE INVENTION

[0013] The power storage device of this embodiment is A plurality of storage elements arranged in a first direction; an extension member adjacent to the plurality of energy storage elements in a second direction perpendicular to the first direction and extending along the first direction; an adjacent member disposed between two adjacent storage elements and fixed to the extension member; The adjacent member is a main body portion extending in a direction perpendicular to the first direction between the energy storage elements; a fastening member disposed at an end of the main body portion in the second direction and used to fasten the adjacent member to the extension member; The thickness dimension in the first direction of the base, which is a portion of the main body other than the arrangement portion where the fastening member is arranged in a third direction perpendicular to each of the first direction and the second direction, is approximately the same as or less than the thickness dimension of the arrangement portion, and the base has a thin-walled portion in at least a part of the third direction that is thinner than the arrangement portion.

[0014] According to this configuration, the thickness dimension of the main body is set to be equal to or less than the placement location (the location where the fastening member is placed) that is most susceptible to load, and the base, which is the other location in the third direction, is set to be thinner than the placement location, and the base has a thin-walled location that is thinner (smaller in thickness) than the placement location, thereby making it possible to thin the adjacent member while ensuring the strength of the fixing location (placement location) with the extension member in the adjacent member.

[0015] In the power storage device, The main body portion is a plurality of the placement portions arranged at intervals in the third direction and each extending in the second direction; the base portion having a plate shape that connects adjacent arrangement portions and extends in a direction perpendicular to the first direction, Each of the arrangement portions abuts against the adjacent member and the adjacent energy storage element, The thin portion may form a gap between the adjacent member and the adjacent energy storage element.

[0016] With this configuration, a flow path through which a temperature-regulating fluid can flow can be formed in the area surrounded by the thin-walled portion, the adjacent arrangement portion sandwiched between the base, and the storage element.In other words, by utilizing the arrangement portion whose thickness dimension is larger than that of the thin-walled portion in order to ensure strength, a flow path through which a temperature-regulating fluid can flow between the adjacent member and the adjacent storage element can be formed.

[0017] In addition, in the power storage device, The base may have a protrusion that protrudes in the first direction and abuts against an energy storage element adjacent to the adjacent member.

[0018] According to this configuration, the protrusions as well as the placement portion come into contact with the energy storage element, so that a sufficient pressing force (force in the first direction) can be applied to the energy storage element.

[0019] In the power storage device, The main body portion is the arrangement portion extending in the second direction and abutting against the energy storage element adjacent to the adjacent member; the base portion having a plate shape extending in a direction perpendicular to the first direction at a position adjacent to the arrangement portion in the third direction, the base portion has a protrusion at a position spaced apart from the arrangement portion in the third direction, the protrusion protruding in the first direction to abut against an energy storage element adjacent to the adjacent member and extending in the second direction, The portion between the arrangement portion and the convex portion in the third direction of the base may constitute the thin-walled portion in which a gap is formed between the adjacent member and the adjacent storage element in the first direction.

[0020] With this configuration, a flow path through which a temperature-regulating fluid can flow can be formed in the area surrounded by the thin-walled portion, the arrangement portion, the convex portion, and the storage element.In other words, by utilizing the arrangement portion, which has a thickness dimension greater than that of the thin-walled portion to ensure strength, and the convex portion protruding from the thin-walled portion, a flow path through which a temperature-regulating fluid can flow for the storage element can be formed between an adjacent member and an adjacent storage element.

[0021] Hereinafter, one embodiment of the present invention will be described with reference to Figures 1 to 8. Note that the names of the components (elements) in this embodiment are those used in this embodiment and may differ from the names of the components (elements) in the background art.

[0022] 1 and 2, the energy storage device includes a plurality of energy storage elements 10 arranged in a predetermined direction, a plurality of adjacent members 2 adjacent to the energy storage elements 10 in the predetermined direction, a holding member 4 that holds the plurality of energy storage elements 10 and the plurality of adjacent members 2, and a first fastening member 5 that fixes at least one adjacent member 2 to the holding member 4. The energy storage device 1 also includes at least one insulator 6 arranged between the plurality of energy storage elements 10 and the holding member 4, and a plurality of bus bars 8 that electrically connect different energy storage elements 10 to each other.

[0023] Each of the plurality of energy storage elements 10 is a primary battery, a secondary battery, a capacitor, or the like. The energy storage element 10 of this embodiment is a chargeable and dischargeable non-aqueous electrolyte secondary battery. More specifically, the energy storage element 10 is a lithium ion secondary battery that utilizes electron transfer that occurs with the transfer of lithium ions.

[0024] Specifically, each energy storage element 10 comprises an electrode body, a case 13 that houses the electrode body together with an electrolyte, an external terminal 14 at least a portion of which is exposed to the outside of the case 13, and a current collector that connects the electrode body and the external terminal 14.

[0025] In the electrode assembly, positive electrodes and negative electrodes are alternately stacked with separators interposed therebetween. In this electrode assembly, lithium ions move between the positive electrodes and negative electrodes, thereby charging and discharging the energy storage device 10.

[0026] The case 13 has a case body 131 having an opening and a plate-shaped cover plate 132 that closes (blocks) the opening of the case body 131. The case body 131 is a rectangular cylindrical shape with a bottom, and the case 13 has a rectangular parallelepiped (six-sided) shape. Specifically, the case body 131 has a rectangular closing portion 131a, a pair of long wall portions 131b extending from each long side of the closing portion 131a in the normal direction to the closing portion 131a, and a pair of short wall portions 131c extending from each short side of the closing portion 131a in the normal direction to the closing portion 131a.

[0027] Case 13 configured as described above has a flat rectangular parallelepiped shape, and a plurality of energy storage elements 10 are arranged in the predetermined direction with the wide surfaces (long wall portions 131b) of case 13 facing each other.

[0028] In the following description, the direction in which multiple storage elements 10 are arranged (first direction) is the X-axis of the Cartesian coordinate system, the direction in which a pair of narrow surfaces (short wall portions 131c) of case 13 face each other (second direction) is the Y-axis of the Cartesian coordinate system, and the normal direction of blocking portion 131a (third direction) is the Z-axis of the Cartesian coordinate system.

[0029] The adjacent members 2 are insulating and are arranged between the energy storage elements 10 lined up in the X-axis direction, or between the energy storage elements 10 and a member (in this embodiment, a part of the holding member 4) lined up in the X-axis direction relative to the energy storage elements 10. The adjacent members 2 form flow paths R between adjacent energy storage elements 10, through which a temperature-regulating fluid (in this embodiment, a gas such as air) can flow. The energy storage device 1 of this embodiment includes a plurality of adjacent members 2, and these plurality of adjacent members 2 include a plurality of types of adjacent members 2A, 2B, and 2C.

[0030] Specifically, the multiple adjacent members 2 include a first adjacent member 2A arranged between two adjacent energy storage elements 10, a second adjacent member (adjacent member) 2B arranged between the adjacent energy storage elements 10 and fixed to the holding member 4, and a third adjacent member 2C adjacent to the energy storage element 10 between the holding member 4 and the energy storage element 10 at the farthest end in the X-axis direction. That is, the energy storage device 1 includes the first adjacent member 2A, the second adjacent member 2B, and the third adjacent member 2C as adjacent members 2. The energy storage device 1 of this embodiment includes multiple first adjacent members 2A, one second adjacent member 2B, and two (a pair) third adjacent members 2C. Each of the multiple first adjacent members 2A is arranged between each of the energy storage elements 10 except for between the energy storage elements 10 between which the second adjacent member 2B is arranged.

[0031] Each of the plurality of first adjacent members 2A has a first main body portion 21A extending in a direction perpendicular to the X-axis direction between adjacent energy storage elements 10 in the X-axis direction, and at least one first restricting portion 25A restricting movement of an energy storage element 10 adjacent to the first main body portion 21A relative to the first main body portion 21A. Also, each of the plurality of first adjacent members 2A forms at least one flow path R between adjacent energy storage elements 10, through which a temperature adjustment fluid can flow.

[0032] The first main body portion 21A is a portion that faces the long wall portion 131b of the case 13 of the energy storage element 10 with a portion of the first main body portion 21A abutting against it. This first main body portion 21A cooperates with an adjacent energy storage element 10 to form a flow path R through which a temperature-regulating fluid can flow between the energy storage element 10 and the first main body portion 21A. In this embodiment, the first main body portion 21A is a rectangular plate having a size corresponding to that of the energy storage element 10 when viewed from the X-axis direction, and has a cross-sectional shape along the XZ plane (a plane including the X-axis direction and the Z-axis direction) that is a rectangular waveform.

[0033] First restricting portions 25A extend in the X-axis direction from at least the corners of rectangular first main body portion 21A and abut against energy storage elements 10 (more specifically, case 13) adjacent to first main body portion 21A from the outside in the YZ plane (a plane including the Y-axis direction and the Z-axis direction), thereby restricting relative movement of energy storage elements 10 with respect to first main body portion 21A in the YZ plane direction. First restricting portions 25A in this embodiment extend from first main body portion 21A toward one side and the other side in the X-axis direction.

[0034] 3 to 8, the second adjacent member 2B has a second main body portion (main body portion) 21B extending in a direction perpendicular to the X-axis direction (YZ plane direction) between two adjacent energy storage devices 10, and a second fastening member (fastening member) 22B arranged at an end of the second main body portion 21B in the Y-axis direction and used to fix the second adjacent member 2B to the holding member 4. The second adjacent member 2B also has at least one second restricting portion 25B that restricts movement of the energy storage device 10 adjacent to the second main body portion 21B relative to the second main body portion 21B. The second adjacent member 2B also has an engaging portion 26B that engages with the holding member 4.

[0035] This second adjacent member 2B also forms at least one flow path R through which the temperature adjustment fluid can flow between adjacent energy storage elements 10. The second adjacent member 2B of this embodiment forms multiple flow paths R between adjacent energy storage elements 10. Furthermore, the second adjacent member 2B of this embodiment is made of resin except for the second fastening member 22B, which is made of metal.

[0036] The second main body portion 21B has a shape corresponding to that of the energy storage device 10 when viewed in the X-axis direction, and the second main body portion 21B of this embodiment has a rectangular shape when viewed in the X-axis direction (see FIG. 6). In the Z-axis direction, the second main body portion 21B has an arrangement portion 211B where the fastening member is arranged, and a base portion 212B which is a portion other than the arrangement portion 211B. The second main body portion 21B of this embodiment has a plurality of arrangement portions 211B and a plurality of base portions 212B. Furthermore, the second main body portion 21B of this embodiment has at least one hollow portion 216B therein (see FIG. 8).

[0037] The multiple arrangement portions 211B are spaced apart along the Z axis and extend in the Y axis direction. Each of the multiple arrangement portions 211B abuts against the energy storage device 10 (more specifically, the long wall portion 131b) adjacent to the second adjacent member 2B. In this embodiment, the multiple arrangement portions 211B are spaced apart in the Z axis direction in the second main body portion 21B, and each arrangement portion 211B extends continuously from one end of the second main body portion 21B to the other end in the Y axis direction. Specifically, when viewed from the Y axis direction, each of the multiple arrangement portions 211B bulges out in an arc shape toward both sides in the X axis direction relative to an adjacent portion in the Z axis direction (a thin-walled portion 213B described later: see FIG. 7), and a second fastening member 22B is disposed at each end in the Y axis direction. In this embodiment, the second main body portion 21B has three arrangement portions 211B.

[0038] Each of the multiple base portions 212B is plate-shaped and extends in a direction perpendicular to the X-axis direction, and the dimension (thickness) of each base portion 212B in the X-axis direction is approximately the same as or less than the thickness of the arrangement portion 211B, and each base portion 212B has a thin portion 213B in at least a portion in the Z-axis direction that is thinner than the arrangement portion 211B. This thin portion 213B forms a gap between the second neighboring member 2B and the adjacent energy storage element 10, and at least a portion of this gap forms a flow path R. In this embodiment, the thickness of the base portion 212B is less than the thickness of the arrangement portion 211B.

[0039] Specifically, the multiple bases 212B include at least one first base (base) 212B1 connecting adjacent arrangement portions 211B in the Z-axis direction, and at least one second base 212B2 that forms an end of the second main body portion 21B in the Z-axis direction and is adjacent to the arrangement portion 211B. In the second main body portion 21B of this embodiment, the first base 212B1 is arranged between each of the arrangement portions 211B. In addition, second bases 212B2 are arranged on the outer sides of the arrangement portion 211B arranged at one end and the arrangement portion 211B arranged at the other end of the multiple arrangement portions 211B arranged at intervals in the Z-axis direction in the second main body portion 21B. That is, the second main body portion 21B of this embodiment has two first bases 212B1 and two second bases 212B2.

[0040] Each first base portion 212B1 has a thin portion 213B and a protrusion 214B that protrudes from the thin portion 213B in the X-axis direction and abuts against an energy storage device 10 adjacent to the second adjacent member 2B.

[0041] The thin portion 213B is a plate-like portion that extends in a plane direction (YZ plane direction) perpendicular to the X-axis direction, and as described above, has a thickness dimension that is smaller than that of the arrangement portion 211B. The thin portion 213B of the first base portion 212B1 extends from one arrangement portion 211B to the other arrangement portion 211B between adjacent arrangement portions 211B that are spaced apart in the Z-axis direction, and also extends from one end to the other end of the second main body portion 21B in the Y-axis direction.

[0042] The protrusion 214B protrudes in the X-axis direction from the thin portion 213B at a position spaced apart from the arrangement portion 211B in the Z-axis direction, abuts against the energy storage device 10 adjacent to the second adjacent member 2B, and extends in the Y-axis direction. In this embodiment, the protrusion 214B protrudes from one surface 2131B and the other surface 2132B of the thin portion 213B in the X-axis direction. That is, the first base portion 212B1 in this embodiment has two protrusions 214B. The protrusion 214B on the one surface 2131B and the protrusion 214B on the other surface 2132B each extend in the Y-axis direction at the same position in the Z-axis direction. In this embodiment, each protrusion 214B is disposed at a central position between the arrangement portions 211B in the Z-axis direction. Furthermore, each protrusion 214B of this embodiment extends continuously from a position spaced apart by a distance d1 from one end of the thin portion 213B in the Y-axis direction to a position spaced apart by a distance d2 from the other end (see FIG. 6). Furthermore, the height (amount of protrusion from the thin portion 213B) of the protrusion 214B is the same at each position in the Y-axis direction, and the width (dimension in the Z-axis direction) is also the same at each position in the Y-axis direction. Furthermore, in the first base portion 212B1 of this embodiment, the distance d1 and the distance d2 are the same.

[0043] Each second base portion 212B2 has a thin portion 213B and a seal portion 215B that protrudes from the thin portion 213B in the X-axis direction and extends in the Y-axis direction.

[0044] The thinned portion 213B of the second base portion 212B2 has a configuration similar to that of the thinned portion 213B of the first base portion 212B1, and the thickness dimension of the thinned portion 213B of the second base portion 212B2 is the same as that of the thinned portion 213B of the first base portion 212B1. Furthermore, the thinned portion 213B on one side in the Z-axis direction (the upper side in FIG. 6) has multiple (two in the example shown in FIG. 6) cutout portions 2135B spaced apart in the Y-axis direction. These cutout portions 2135B are recessed from one edge toward the other edge in the Z-axis direction.

[0045] The seal portion 215B extends continuously from one end to the other end of the second main body portion 21B in the Y-axis direction and is in close contact with the energy storage device 10 adjacent to the second adjacent member 2B. In this embodiment, two seal portions 215B are arranged on each of one surface 2131B and the other surface 2132B of the thin-walled portion 213B in the X-axis direction. Each seal portion 215B on the one surface 2131B is arranged at the same position in the Z-axis direction as the corresponding seal portion 215B on the other surface 2132B. The width of each seal portion 215B at each position in the Y-axis direction (dimension in the Z-axis direction) is smaller than the width of the protruding portion 214B, and at least the tip portion (top portion) of each seal portion 215B in the protruding direction (X-axis direction) is in close contact with the energy storage device 10. Furthermore, the seal portion 215B in this embodiment extends to the second restricting portion 25B.

[0046] At least one hollow portion 216B is a hole extending from one end face of the second main body portion 21B to the other end face in the Z-axis direction, or a hole extending from the other end face to one end face. The second main body portion 21B of this embodiment has multiple hollow portions 216B (see FIG. 8). These multiple hollow portions 216B reduce the weight of the second adjacent member 2B and suppress shrinkage during molding.

[0047] The second fastening members 22B are disposed at each end of each disposition portion 211B in the Y-axis direction. That is, the second adjacent member 2B has a plurality of second fastening members 22B. Each of the plurality of second fastening members 22B fastens the second adjacent member 2B and the holding member 4 by engaging with a first fastening member 5. In this embodiment, each second fastening member 22B is an insert nut and has a female thread on the inner circumferential surface of a hole extending in the Y-axis direction. Furthermore, each first fastening member 5 in this embodiment is a bolt and fastens the second adjacent member 2B and the holding member 4 by engaging (screwing) with the second fastening member 22B.

[0048] In the second adjacent member 2B of this embodiment, three second fastening members 22B are arranged at each end in the Y-axis direction with a gap in the Z-axis direction, and the second fastening member 22B at one end of these three second fastening members 22B and the second fastening member 22B at the other end engage with the first fastening member 5 that has been inserted through the retaining member 4, thereby fastening the second adjacent member 2B and the retaining member 4. Furthermore, when another component such as a duct is attached to the energy storage device 1, the central second fastening member 22B of the three second fastening members 22B engages with the first fastening member 5 that has been inserted through the retaining member 4 as well, thereby fastening the second adjacent member 2B, the retaining member 4, and the other component.

[0049] The second restricting portions 25B extend in the X-axis direction from at least the corners of the rectangular periphery of the second main body portion 21B when viewed in the X-axis direction, and restrict relative movement of the energy storage elements 10 in the YZ plane direction with respect to the second adjacent member 2B by abutting against the energy storage elements 10 adjacent to the second adjacent member 2B from the outside in the YZ plane direction. The second restricting portions 25B extend from the second main body portion 21B to both sides in the X-axis direction.

[0050] The engaging portions 26B protrude in the Y-axis direction from an end (end surface) of the second main body portion 21B in the Y-axis direction. Specifically, a plurality of engaging portions 26B are arranged at intervals in the Z-axis direction on the end surface of the second main body portion 21B in the Y-axis direction. In the second neighboring member 2B of this embodiment, two engaging portions 26B are arranged at intervals in the Z-axis direction on each end of the second main body portion 21B in the Y-axis direction. Each of these two engaging portions 26B has a cylindrical shape with a tapered tip, and is arranged at a position corresponding to each first base portion 212B1 in the Z-axis direction (i.e., between the arrangement portions 211B).

[0051] 1 and 2, each of the two third adjacent members 2C has a third main body portion 21C extending in a direction perpendicular to the X-axis direction between the energy storage elements 10 adjacent in the X-axis direction and a portion of the holding member 4 (a terminal member 41 described later), and at least one third restricting portion 25C that restricts movement of the energy storage elements 10 adjacent to the third main body portion 21C relative to the third main body portion 21C. In addition, each of the two third adjacent members 2C forms at least one flow path R between the adjacent energy storage elements 10 and the third adjacent member 2C, through which a temperature adjustment fluid can flow.

[0052] The third main body portion 21C is a portion that faces the long wall portion 131b of the energy storage element 10 while partially abutting against it. Like the first main body portion 21A of the first adjacent member 2A and the second main body portion 21B of the second adjacent member 2B, this third main body portion 21C also cooperates with the adjacent energy storage element 10 to form a flow path R through which a temperature-regulating fluid can flow between the third main body portion 21C and the adjacent energy storage element 10. The third main body portion 21C of this embodiment forms a plurality of flow paths R between the third main body portion 21C and the adjacent energy storage element 10.

[0053] Specifically, third main body portion 21C has a rectangular plate shape with a size corresponding to that of adjacent energy storage elements 10 when viewed in the X-axis direction. More specifically, third main body portion 21C extends in a direction perpendicular to the X-axis direction at each of one end and the other end of energy storage device 1 in the X-axis direction, and has two opposing surfaces 210C opposing adjacent energy storage elements 10 (long wall portions 131b of case 13) or terminal members 41, and a plurality of ridges 214C protruding from opposing surfaces 210C opposing energy storage elements 10.

[0054] On the facing surface 210C facing the energy storage devices 10, each of the multiple ridges 214C extends in the Y-axis direction and is arranged at intervals in the Z-axis direction. The tip of each of the multiple ridges 214C in the protruding direction (X-axis direction) abuts against the energy storage devices 10 adjacent to the third main body portion 21C. As a result, a flow path R is formed on the energy storage device 10 side of the third main body portion 21C by the facing surface 210C on the energy storage device 10 side, the two ridges 214C adjacent to each other at an interval in the Z-axis direction on the facing surface 210C, and the energy storage devices 10 (case 13) facing the facing surface 210C.

[0055] Third restricting portion 25C extends in the X-axis direction from at least a corner of rectangular third main body portion 21C and abuts against energy storage element 10 (more specifically, case 13) adjacent to third main body portion 21C from the outside in the YZ plane direction, thereby restricting relative movement of energy storage element 10 in the YZ plane direction with respect to third main body portion 21C. Third restricting portion 25C of this embodiment extends from third main body portion 21C toward one side in the X-axis direction (toward energy storage element 10).

[0056] The holding member 4 surrounds the plurality of energy storage elements 10 and the plurality of adjacent members 2, thereby collectively holding the plurality of energy storage elements 10 and the plurality of adjacent members 2. The holding member 4 is made of a conductive material such as a metal.

[0057] Specifically, the holding member 4 has a pair of end members 41 arranged on both sides of the plurality of energy storage elements 10 (a stack of energy storage elements 10) in the X-axis direction, and an extension member 42 adjacent to the plurality of energy storage elements 10 in the Y-axis direction and extending along the X-axis direction. The holding member 4 of this embodiment has a pair of extension members 42, and each of the pair of extension members 42 connects the pair of end members 41 to each other. The holding member 4 also has at least one fastening member 43 that fastens the end member 41 and the extension member 42. The holding member 4 of this embodiment has a plurality of fastening members 43.

[0058] Each of the pair of end members 41 is arranged so as to sandwich the third adjacent member 2C between itself and the energy storage element 10 arranged at the end (outermost) in the X-axis direction. Each of the pair of end members 41 is a rectangular plate having a size corresponding to that of the energy storage element 10 when viewed in the X-axis direction. Specifically, each end member 41 has a rectangular shape that is elongated in the Y-axis direction, and has a plurality of through holes 411 arranged at intervals in the Z-axis direction at both ends in the Y-axis direction.

[0059] Each of the pair of extension members 42 has an extension member main body 420 facing the short wall portion 131c of each storage element 10, a first piece portion 421 extending from one end (upper in Figure 2) of the extension member main body 420 in the Z-axis direction along the Y-axis direction along the cover plate 132 of each storage element 10 and also extending in the X-axis direction, a second piece portion 422 extending from the other end of the extension member main body 420 in the Z-axis direction along the blocking portion 131a of each storage element 10 and also extending in the X-axis direction, and a pair of third pieces 423 extending from each end of the extension member main body 420 in the X-axis direction along the terminal member 41 in the Y-axis direction and also extending in the Z-axis direction.

[0060] The elongated member main body 420 is in the shape of a plate extending along the short wall portion 131c of each energy storage element 10, and has a plurality of first through holes 4201 penetrating in the Y-axis direction to allow the temperature adjustment fluid to flow into and out of each flow path R, and a plurality of second through holes 4202 penetrating in the Y-axis direction at positions corresponding to the second fastening members 22B of the second adjacent member 2B. The elongated member main body 420 also has a third through hole 4203 penetrating in the Y-axis direction at a position corresponding to the engaging portion 26B of the second adjacent member 2B. The first fastening member 5 is inserted into the second through hole 4202, and the engaging portion 26B of the second adjacent member 2B is inserted into the third through hole 4203.

[0061] The first arm 421 is strip-shaped and long in the X-axis direction, and its dimension (width) in the Y-axis direction is constant at each position in the X-axis direction. The second arm 422 is strip-shaped and long in the X-axis direction, and its dimension (width) in the Y-axis direction is constant at each position in the X-axis direction. The width of the second arm 422 is greater than the width of the first arm 421. Each of the pair of third arms 423 has a plurality of through holes 4231 spaced apart in the Z-axis direction. Each of the through holes 4231 is located at a position corresponding to a through hole 411 in the termination member.

[0062] Each of the multiple fastening members 43 fastens the end member 41 and the extension member 42 together while being inserted through the through hole 411 of the end member 41 and the through hole 4231 of the extension member 42 (third piece portion 423). Each fastening member 43 in this embodiment is composed of a bolt 431 and a nut 432.

[0063] The insulator 6 has insulating properties. The insulator 6 is disposed between the extension member 42 and the plurality of energy storage elements 10. Specifically, the energy storage device 1 includes a pair of insulators 6, and each insulator 6 covers at least an area of ​​the extension member 42 that faces the plurality of energy storage elements 10. As a result, each insulator 6 provides insulation between the extension member 42 and the plurality of energy storage elements 10. Each insulator 6 has through holes 61, 62, 63 of a size and shape corresponding to the through holes 4201, 4202, 4203 of the extension member main body 420 at positions corresponding to the through holes (first through hole 4201, second through hole 4202, third through hole 4203) of the extension member main body 420, respectively.

[0064] Each of the bus bars 8 is a plate-like member having electrical conductivity, such as metal. Each bus bar 8 electrically connects the external terminals 14 of the energy storage elements 10 to each other. The bus bars 8 of this embodiment connect (connect) the energy storage elements 10 included in the energy storage device 1 in series.

[0065] According to the above-described energy storage device 1, the thickness dimension of second main body portion 21B of second adjacent member 2B is set to be equal to or smaller than arrangement portion 211B (the portion where second fastening member 22B is arranged), which is prone to load, and base portion 212B, which is another portion in the Z-axis direction, is set to be smaller than arrangement portion 211B, and first base portion 212B1 has thin portion 213B that is thinner (smaller in thickness) than arrangement portion 211B, thereby making it possible to thin second adjacent member 2B while ensuring the strength of the fixed portion (arrangement portion 211B) of second adjacent member 2B with extension member 42. This makes it possible to reduce the size of energy storage device 1 in the X-axis direction, or, if the dimension of energy storage device 1 in the X-axis direction is not changed, to increase the width in the X-axis direction of each flow path R formed between energy storage elements 10 and improve cooling efficiency and heating efficiency.

[0066] Furthermore, in the second adjacent member 2B of the energy storage device 1 of this embodiment, the second main body portion 21B includes a plurality of arrangement portions 211B spaced apart in the Z-axis direction and each extending in the Y-axis direction, and a plate-shaped first base portion 212B1 connecting adjacent arrangement portions 211B and extending in a direction perpendicular to the X-axis direction (YZ plane direction). Each arrangement portion 211B abuts against an energy storage element 10 adjacent to the second adjacent member 2B, and the thin-walled portion 213B forms a gap between the second adjacent member 2B and the adjacent energy storage element 10. In other words, in the second adjacent member 2B, the main body portion includes arrangement portions 211B extending in the Y-axis direction and abutting against an energy storage element 10 adjacent to the second adjacent member 2B, and a plate-shaped first base portion 212B1 extending in a direction perpendicular to the X-axis direction at a position adjacent to the arrangement portion 211B in the Z-axis direction. The first base portion 212B1 has a convex portion 214B that protrudes in the X-axis direction and abuts against the energy storage elements 10 adjacent to the second adjacent member 2B and extends in the Y-axis direction at a position spaced apart from the arrangement portion 211B in the Z-axis direction, and the portion of the first base portion 212B1 between the arrangement portion 211B and the convex portion 214B in the Z-axis direction forms a thin portion 213B where a gap is formed between the second adjacent member 2B and the adjacent energy storage elements 10 in the X-axis direction. This makes it possible to form a flow path R in the energy storage device 1 that allows a temperature adjustment fluid to flow in a region surrounded by the thin portion 213B, the arrangement portions 211B adjacent to each other across the first base portion 212B1, and the energy storage elements 10. That is, by utilizing the placement portion 211B, which has a thickness dimension larger than that of the thin-walled portion 213B to ensure strength, a flow path R can be formed between the second adjacent member 2B and the adjacent storage element 10, through which a fluid for regulating the temperature of the storage element 10 can flow.

[0067] Furthermore, in the second adjacent member 2B of the energy storage device 1 of this embodiment, the first base portion 212B1 has a convex portion 214B that protrudes in the X-axis direction and abuts against the energy storage element 10 adjacent to the second adjacent member 2B. In this way, by having the convex portion 214B abut against the energy storage element 10 in addition to the arrangement portion 211B, a sufficient pressing force (force in the X-axis direction) can be applied to the energy storage element 10.

[0068] The power storage device of the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention. For example, the configuration of one embodiment can be added to the configuration of another embodiment, or part of the configuration of one embodiment can be replaced with the configuration of another embodiment. Furthermore, part of the configuration of one embodiment can be deleted.

[0069] In the second adjacent member 2B of the energy storage device 1 of the above embodiment, the convex portion 214B extends continuously in the Y-axis direction between positions spaced apart by intervals d1 and d2 from each end edge of the second main body portion 21B in the Y-axis direction (see Figure 6), but is not limited to this configuration.

[0070] The convex portion 214B does not have to be configured to extend in a predetermined direction (convex strip) as described above, but may be, for example, a columnar shape extending in the X-axis direction, a cone or truncated cone shape (see FIG. 9), or a hemispherical shape.

[0071] Furthermore, the protrusions 214B may extend discontinuously in the Y-axis direction, or may be configured to be curved or bent in whole or in part (i.e., they may not extend straight in the Y-axis direction). Furthermore, the width of the protrusions 214B at each position in the Y-axis direction (the dimension in the Z-axis direction) may not be the same.

[0072] Furthermore, in the second main body portion 21B in the above embodiment, the positions in the Z axis direction of the convex portion 214B on one surface in the X axis direction and the convex portion 214B on the other surface are the same, but may be different.

[0073] That is, convex portion 214B is not limited to any particular shape as long as it protrudes from thin portion 213B in the X-axis direction and comes into contact with energy storage devices 10 adjacent to second adjacent member 2B.

[0074] Furthermore, in the second neighboring member 2B of the above embodiment, the first base portion 212B1 has one convex portion 214B on each of the faces 2131B, 2132B in the X-axis direction, but is not limited to this configuration. The first base portion 212B1 may have a plurality of convex portions 214B arranged at intervals in the Z-axis direction on each of the faces 2131B, 2132B in the X-axis direction. Furthermore, the first base portion 212B1 may be configured without any convex portions 214B (i.e., the entire first base portion 212B1 may be configured with the thin-walled portion 213B).

[0075] Furthermore, in the second adjacent member 2B of the energy storage device 1 of the above embodiment, the thickness dimension (dimension in the X-axis direction) of the first base portion 212B1, more specifically, the distance in the X-axis direction between the tips of the convex portions 214B on both sides of the first base portion 212B1, is equal to or less than the thickness dimension of the arrangement portion 211B, but is not limited to this configuration. The first base portion 212B1 may partially have a portion whose thickness dimension is slightly greater than that of the arrangement portion 211B. That is, the thickness dimension of the first base portion 212B1 may be equal to or less than the thickness dimension of the arrangement portion 211B.

[0076] Specifically, in the first base portion 212B1, the tip (top) of the protrusion 214B may protrude slightly (for example, 0.005 mm) in the X-axis direction from the arrangement portion 211B. This protrusion amount is such that even when expansion (expansion of the case 13) occurs in the energy storage element 10 adjacent to the second adjacent member 2B due to deterioration over time or charge / discharge, the abutment of each arrangement portion 211B and each protrusion 214B on the second adjacent member 2B with the energy storage element 10 (case 13) is maintained.

[0077] Furthermore, although the energy storage device 1 in the above embodiment includes one second adjacent member 2B, it may include a plurality of second adjacent members 2B.

[0078] In the above embodiment, the case where the energy storage element is used as a chargeable and dischargeable non-aqueous electrolyte secondary battery (for example, a lithium ion secondary battery) has been described, but the type and size (capacity) of the energy storage element are arbitrary. In the above embodiment, a lithium ion secondary battery has been described as an example of the energy storage element, but the present invention is not limited to this. For example, the present invention can also be applied to energy storage elements of various secondary batteries, as well as primary batteries and capacitors such as electric double layer capacitors. [Explanation of symbols]

[0079] 1...electricity storage device, 2...adjacent member, 2A...first adjacent member, 2B...second adjacent member (adjacent member), 2C...third adjacent member, 21A...first main body portion, 21B...second main body portion (main body portion), 21C...third main body portion, 210C...opposing surface, 211B...arrangement portion, 212B...base portion, 212B1...first base portion (base portion), 212B2...second base portion, 213B...thin portion, 2131B... One surface, 2132B...other surface, 2135B...notch portion, 214B...projection portion, 214C...projection strip, 215B...seal portion, 216B...hollow portion, 22B...second fastening member, 25A...first restriction portion, 25B...second restriction portion, 25C...third restriction portion, 26B...engagement portion, 4...retaining member, 41...terminating member, 411...through hole, 42...extension member, 420...extension member main body, 4201... First through hole, 4202...second through hole, 4203...third through hole, 421...first arm portion, 422...second arm portion, 423...third arm portion, 4231...through hole, 43...fastening member, 431...bolt, 432...nut, 5...first fastening member, 6...insulator, 61, 62, 63...through hole, 8...bus bar, 10...storage element, 13...case, 131...case main body, 131a...blocking portion, 131b...long wall portion, 131c...short wall portion, 132...cover plate, 14...external terminal, 500...storage module, 501...storage battery, 502...separator, 503...end holder, 504...end plate, 505...restraint band, 5051...flat surface, 5052, 5053...hole portion, 506...intermediate plate, 507a, 507b...screw hole, d1, d2...spacing, R...flow path

Claims

1. A plurality of storage elements arranged in a first direction; an extension member adjacent to the plurality of energy storage elements in a second direction perpendicular to the first direction and extending along the first direction; an adjacent member disposed between two adjacent storage elements and fixed to the extension member; The adjacent member is a main body portion extending in a direction perpendicular to the first direction between the energy storage elements; a fastening member disposed at an end of the main body portion in the second direction and used to fasten the adjacent member to the extension member; a thickness dimension in the first direction of a base, which is a portion of the main body portion other than the arrangement portion where the fastening member is arranged in a third direction perpendicular to each of the first direction and the second direction, is approximately equal to or less than the thickness dimension of the arrangement portion, and the base has a thin-walled portion in at least a part of the third direction that is thinner than the arrangement portion.

2. The main body portion is a plurality of the placement portions arranged at intervals in the third direction and each extending in the second direction; the base portion having a plate shape that connects adjacent arrangement portions and extends in a direction perpendicular to the first direction, Each of the arrangement portions abuts against the adjacent member and the adjacent energy storage element, The energy storage device according to claim 1 , wherein the thin portion forms a gap between the adjacent member and the adjacent energy storage element.

3. The energy storage device according to claim 2 , wherein the base portion has a protrusion that protrudes in the first direction and abuts against an energy storage element adjacent to the adjacent member.

4. The main body portion is the arrangement portion extending in the second direction and abutting against the energy storage element adjacent to the adjacent member; the base portion having a plate shape extending in a direction perpendicular to the first direction at a position adjacent to the arrangement portion in the third direction, the base portion has a protrusion at a position spaced apart from the arrangement portion in the third direction, the protrusion protruding in the first direction to abut against an energy storage element adjacent to the adjacent member and extending in the second direction, 2. The energy storage device of claim 1, wherein the portion of the base between the arrangement portion and the convex portion in the third direction constitutes the thin-walled portion in which a gap is formed between the adjacent member and the adjacent energy storage element in the first direction.

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