Electricity storage device and pressure absorbing member

Abstract

To provide a power storage device capable of suppressing deformation of a stretching member caused by expansion.SOLUTION: A power storage device includes a plurality of power storage elements 1 arranged in a first direction X, a pair of extending members 31 extending in the first direction and sandwiching the plurality of storage elements from both sides in a second direction Y orthogonal to the first direction, a pressure absorbing member 5 at least partially elastically deformable in the first direction, and a spacer 2A which is an adjacent member adjacent to the pressure absorbing member in the first direction, and the pressure absorbing member and the adjacent member are arranged between adjacent power storage elements.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to an electric storage device including a plurality of electric storage elements arranged in a first direction and an extension member disposed along the plurality of electric storage elements, and to a pressure absorbing member provided between the electric storage elements. [Background technology]

[0002] A known battery system includes a plurality of energy storage elements arranged in a first direction and a connecting bar (extension member) disposed along the plurality of energy storage elements (see, for example, Patent Document 1). Specifically, as shown in Fig. 10, this battery system includes a plurality of stacked battery cells 102, a pair of end plates 140 disposed on both ends of the plurality of battery cells 102, and a connecting bar 143 disposed on both side surfaces of the plurality of battery cells 102. The connecting bar 143 is strip-shaped, and both ends of the connecting bar 143 in a predetermined direction are bent inward to provide bent pieces that are fixed to the end plates 140. This secures the plurality of battery cells 102 in a stacked state.

[0003] However, when an electric storage device is used for a long period of time, the electric storage element may expand. Furthermore, in recent years, the capacity of electric storage elements has increased, and the amount of expansion of the electric storage element due to use tends to be large. Therefore, when such an electric storage device is used for a long period of time, there is a risk that the extension member will be deformed due to the expansion of the electric storage element. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-170258 Summary of the Invention [Problem to be solved by the invention]

[0005] Therefore, an object of this embodiment is to provide an electricity storage device and a pressure absorbing member that can suppress deformation of the extension member caused by expansion of the electricity storage element. [Means for solving the problem]

[0006] The power storage device of this embodiment is A plurality of storage elements arranged in a first direction; a pair of extension members extending in the first direction and sandwiching the plurality of energy storage elements from both sides in a second direction perpendicular to the first direction; a pressure absorbing member at least a portion of which is elastically deformable in the first direction; an adjacent member adjacent to the pressure absorbing member in the first direction, The pressure absorbing member and the adjacent member are disposed between adjacent energy storage elements.

[0007] According to this configuration, the pressure absorption member elastically deforms when a force is applied from the outside in the first direction, so that when the storage element expands, the pressure absorption member can absorb the force caused by the expansion, thereby suppressing deformation of the extension member caused by the expansion of the storage element.

[0008] In the power storage device, The adjacent member may form a flow path between the adjacent member and the pressure absorbing member, through which a fluid can flow.

[0009] In the power storage device, The pressure absorbing member may have the same outer dimensions as the energy storage element.

[0010] According to this configuration, the pressure absorbing member can be disposed in a location in the electricity storage device where the electricity storage element can be disposed, that is, it can be disposed in place of the electricity storage element.

[0011] In the power storage device, The pressure absorbing member may have an elastic portion that is elastically deformable in the first direction, and a pair of clamping portions that sandwich the elastic portion from both sides in the first direction and are capable of transmitting external forces in the first direction to the elastic portion.

[0012] According to this configuration, when a force is applied to the pair of clamping portions from the outside in the first direction, the elastic portion of the pressure absorption member elastically deforms, so that when the storage element expands, the pressure absorption member can absorb the force caused by the expansion, thereby suppressing deformation of the extension member caused by the expansion of the storage element.

[0013] In the power storage device, The energy storage element has a rectangular shape, the elastic portion has a first portion and a second portion disposed on an outer side of the first portion in a direction perpendicular to the first direction, The first portion may be more elastically deformable than the second portion.

[0014] With this configuration, when the storage element expands during use, the amount of expansion is greater at the center of the storage element. Therefore, by changing the ease of elastic deformation between the first portion of the pressure absorption member that overlaps with the center of the storage element and the second portion on the outside, when the storage element expands, the force can be absorbed by the entire pressure absorption member.

[0015] In the power storage device, each of the pair of clamping portions is a plate-shaped member extending in a direction perpendicular to the first direction, The rigidity of each of the pair of clamping portions may be greater than the rigidity of the elastic portion.

[0016] With this configuration, even if a force due to the expansion of the energy storage element or the like is applied to a part of the clamping portion (plate-shaped member), the clamping portion has sufficient rigidity, so that this force is transmitted to the elastic portion in a spread state across the entire clamping portion, and the pressure absorbing member can effectively mitigate this force.

[0017] In the power storage device, One of the pair of clamping portions and the other clamping portion may be members having the same shape.

[0018] According to this configuration, the pair of clamping portions are members of the same shape, so that the number of types of parts can be reduced.

[0019] In the power storage device, one of the pair of clamping portions has an abutment portion extending toward the other of the pair of clamping portions, A gap may be formed between the contact portion and the other clamping portion when the elastic portion is not elastically deformed.

[0020] According to this configuration, when a force in the first direction is applied to each clamping portion, the abutment portion abuts against the other clamping portion, thereby preventing the clamping portions from coming closer to each other, and thereby preventing the elastic portion from being crushed too much.

[0021] The pressure absorbing member of this embodiment is A pressure absorbing member that can be placed between adjacent energy storage elements in an energy storage device including a plurality of energy storage elements arranged in a predetermined direction, A pair of clamping portions arranged at an interval from each other; an elastic portion disposed between the pair of clamping portions, the pair of clamping portions are capable of transmitting an external force to the elastic portion in an arrangement direction of the pair of clamping portions, The elastic portion is characterized in that it is elastically deformable in the arrangement direction.

[0022] According to this configuration, when the pressure absorption member is arranged between the storage elements so that the arrangement direction of the clamping portions is aligned with the stacking direction of the storage elements, the elastic portions of the pressure absorption member elastically deform when a force is applied to the pair of clamping portions from outside in the first direction, so that when the storage elements expand, the pressure absorption member can absorb the force caused by the expansion.As a result, for example, in a storage device in which multiple storage elements are fixed in a stacked state by extension members, when the pressure absorption member is arranged so that the arrangement direction of the storage elements is aligned with the arrangement direction of the clamping portions, deformation of the extension members caused by the expansion of the storage elements is suppressed. [Effects of the Invention]

[0023] According to the electricity storage device of this embodiment, it is possible to provide an electricity storage device and a pressure absorbing member that can suppress deformation of the extension member due to expansion of the electricity storage element. [Brief explanation of the drawings]

[0024] [Figure 1] FIG. 1 is a perspective view of an electricity storage device according to one embodiment of the present invention. [Figure 2] FIG. 2 is a perspective view of an energy storage element in the energy storage device according to the embodiment. [Figure 3] FIG. 3 is a front view of an energy storage element in the energy storage device according to the embodiment. [Figure 4] FIG. 4 is an exploded perspective view of the electricity storage device according to the embodiment. [Figure 5] FIG. 5 is a perspective view of an inner spacer, an outer spacer, and an energy storage element of the energy storage device according to the embodiment. [Figure 6] FIG. 6 is an exploded perspective view of a pressure absorbing member in the electricity storage device according to the embodiment. [Figure 7A] FIG. 7A is a cross-sectional view and an enlarged view of a main part of the pressure absorbing member in a state in which the elastic portion is not elastically deformed in the power storage device according to the same embodiment. [Figure 7B] FIG. 7B is a cross-sectional view and an enlarged view of a main part of the pressure absorbing member in a state where the elastic portion in the power storage device according to the same embodiment is elastically deformed. [Figure 8A] FIG. 8A is a perspective view of an elastic member in a power storage device according to a modified example. [Figure 8B] FIG. 8B is a front view of the elastic member of FIG. 8A. [Figure 8C] FIG. 8C is a front view of the elastic member of FIG. 8A with a portion cut away. [Figure 9A] FIG. 9A is a perspective view of an elastic member in an electricity storage device according to a modified example. [Figure 9B] FIG. 9B is a perspective view of an elastic member in a power storage device according to a modified example. [Figure 10] FIG. 10 is a perspective view for explaining a conventional electricity storage device. DETAILED DESCRIPTION OF THE INVENTION

[0025] Hereinafter, one embodiment of the present invention will be described with reference to Figures 1 to 7. 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.

[0026] 1, the energy storage device includes a plurality of energy storage elements 1 arranged in a first direction, a pair of extension members 31 extending in the first direction and sandwiching the plurality of energy storage elements from both sides in a second direction perpendicular to the first direction, a pressure absorbing member 5 at least a portion of which is elastically deformable in the first direction, and at least one spacer (adjacent member) 2 adjacent to the pressure absorbing member 5 in the first direction. In the energy storage device, the pressure absorbing member 5 and the spacer 2 are disposed between adjacent energy storage elements 1. Furthermore, in this energy storage device, the spacer 2 is also adjacent to the energy storage element 1.

[0027] The energy storage device further includes a holding member 3 that collectively holds the energy storage elements 1, the spacers 2, and the pressure absorbing members 5, and the extension members 31 are part of the holding member 3. The holding member 3 is made of a conductive material. Accordingly, the energy storage device includes an insulator 4 that is disposed between the energy storage elements 1 and the holding member 3.

[0028] This embodiment includes a plurality of spacers 2. In this electricity storage device, the plurality of spacers 2 are arranged in the first direction, and the electricity storage elements 1 or the pressure absorbing members 5 are disposed between the spacers 2.

[0029] In the following description, for convenience, each direction will be described using an orthogonal coordinate system including an X-axis direction, a Y-axis direction, and a Z-axis direction. The direction in which the energy storage elements 1 are aligned (first direction) will be referred to as the X-axis direction. Furthermore, one of the two axial directions perpendicular to the direction in which the energy storage elements 1 are aligned (X-axis direction) will be referred to as the Y-axis direction, and the remaining direction (third direction) will be referred to as the Z-axis direction. Accordingly, each drawing additionally illustrates three orthogonal axes (coordinate axes) corresponding to the X-axis direction, Y-axis direction, and Z-axis direction, respectively.

[0030] 2 and 3, the energy storage element 1 includes an electrode assembly including a positive electrode and a negative electrode, a case 10 that houses the electrode assembly, and a pair of external terminals 11 arranged on the outer surface of the case 10. The energy storage element 1 has a rectangular shape.

[0031] 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 has a pair of external terminals 11 arranged on the outer surface of the cover plate 101.

[0032] The case body 100 includes a closing portion 100a (see FIG. 3) 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 in this embodiment has a flattened rectangular cylindrical shape.

[0033] The body portion 100b includes a pair of first walls 100c facing each other with a gap therebetween, and a pair of second walls 100d facing each other with the pair of first walls 100c sandwiched therebetween.

[0034] The first wall 100c and the second wall 100d are each formed in a rectangular shape. The body 100b is formed in a square cylindrical shape. One end of the body 100b is closed by a closing portion 100a. In contrast, the other end of the body 100b is open and closed by a cover plate 101.

[0035] The plurality of energy storage elements 1 are aligned in one direction (see FIG. 1). In this embodiment, the plurality of energy storage elements 1 are aligned with the first wall 100c of the case 10 facing in one direction. The energy storage device includes a bus bar that electrically connects the external terminals 11 of two adjacent energy storage elements 1.

[0036] The pressure absorbing member 5 can be arranged in an energy storage device that includes a plurality of energy storage elements 1 arranged in the X-axis direction (a predetermined direction). The pressure absorbing member 5 is plate-shaped and extends in a direction perpendicular to the X-axis direction (extending in the Y-axis and Z-axis directions that are orthogonal to the X-axis direction). The pressure absorbing member 5 is made of an insulating material.

[0037] 6, in the electricity storage device of this embodiment, the pressure absorbing member 5 has an elastic portion 50 that is elastically deformable in the X-axis direction, and a pair of clamping portions 51 that sandwich the elastic portion 50 from both sides in the X-axis direction and are capable of transmitting an external force in the X-axis direction to the elastic portion 50. In other words, the pressure absorbing member 5 has a pair of clamping portions 51 that are aligned with a gap between them, and the elastic portion 50 that is disposed between the pair of clamping portions 51, and the pair of clamping portions 51 are capable of transmitting an external force to the elastic portion 50 in the alignment direction of the pair of clamping portions 51, and the elastic portion 50 is elastically deformable in the X-axis direction (alignment direction).

[0038] In the electricity storage device of this embodiment, one pressure absorbing member 5 is disposed (see FIG. 1). The pressure absorbing member 5 is disposed in the center of the electricity storage device in the X-axis direction. This allows the load acting on the pressure absorbing member 5 to be halved when an impact load is applied to the electricity storage device, compared to when the pressure absorbing member 5 is disposed at an end of the electricity storage device in the X-axis direction.

[0039] Each of the pair of clamping portions 51 is a plate-shaped member (see FIG. 6). Each of the pair of clamping portions 51 extends in the Y-axis direction and the Z-axis direction, which are orthogonal to the X-axis direction. The pair of clamping portions 51 are plate-shaped members spaced apart from each other with the elastic portion 50 sandwiched between them. One clamping portion 52 and the other clamping portion 53 of the pair of clamping portions 51 are members of the same shape. Specifically, the shape of the clamping portion 51 as viewed from the X-axis direction is the same as the shape of the energy storage device 1 as viewed from the X-axis direction (for example, the shape of the case 10 as viewed from the X-axis direction), and is specifically rectangular. In this embodiment, one clamping portion 52 is disposed in a state where the other clamping portion 53 is inverted around the Z-axis direction.

[0040] Furthermore, the rigidity of each of the pair of clamping portions 51 is greater than the rigidity of the elastic portion 50. The material of the clamping portions 51 is, for example, a resin such as polypropylene.

[0041] The external dimensions of the pressure absorbing member 5 are the same as those of the energy storage element 1. In this embodiment, the external diameter of the clamping portions 51 is the same as those of the energy storage element 1. These external diameters refer to the external dimensions of each member when viewed from the X-axis direction. In this embodiment, the shape of the pressure absorbing member 5 is determined by the pair of clamping portions 51, which have high rigidity, and therefore the external diameter of the pressure absorbing member 5 does not change even if the elastic portions 50 are elastically deformed in the X-axis direction.

[0042] Each clamping portion 51 has a first surface 511 and a second surface 512 located on the opposite side of the first surface 511. One clamping portion 52 of the pair of clamping portions 51 has protruding portions 514, 516 as abutment portions extending toward the other clamping portion 53 of the pair of clamping portions 51. When the elastic portion 50 is not elastically deformed, a gap (gap in the X-axis direction) is formed between the protruding portions 514, 516 and the other clamping portion 53. In this embodiment, each clamping portion 51 has a fixing portion 513 provided on the first surface 511 and fixed to the elastic portion 50, and protruding portions 514, 515, 516 protruding from the first surface 511 toward the elastic portion 50 in the X-axis direction.

[0043] The pair of clamping portions 51 are arranged with their first surfaces 511 facing each other. Specifically, the pair of clamping portions 51 are fixed to the elastic portion 50 at fixing portions 513 of the first surfaces 511. In the energy storage device of this embodiment, the pair of clamping portions 51 are fixed to the elastic portion 50 with an adhesive at a plurality of fixing portions 513 (for example, six fixing portions 513 provided in an area excluding the outer periphery of the first surface 511).

[0044] In this embodiment, the fixing portions 513 are protrusions that protrude toward the elastic portion 50 in the X-axis direction. Each fixing portion 513 has the same shape and size. Furthermore, some of the multiple fixing portions 513 are arranged on one side in the Z-axis direction and aligned in the Y-axis direction. The remaining fixing portions 513 are arranged on the other side in the Z-axis direction and aligned in the Y-axis direction. The fixing portions 513 arranged on one side in the Z-axis direction are arranged at equal intervals in the Y-axis direction. Similarly, the fixing portions 513 arranged on the other side in the Z-axis direction are arranged at equal intervals in the Y-axis direction.

[0045] Protrusions 514, 515, and 516 are protrusions that protrude toward elastic portion 50 in the X-axis direction, and are, for example, ribs. The protrusion amounts in the X-axis direction of protrusions 514 and 516 are all equal and greater than the protrusion amount in the X-axis direction of protrusion 515. In other words, the dimensions in the X-axis direction of protrusions 514 and 516 are equal and smaller than the dimension in the X-axis direction of protrusion 515.

[0046] The protruding portion 516 extends from one end in the Y-axis direction of the first surface 511 to the other end in the Z-axis direction of the periphery of the clamping portion 51. As a result, in this embodiment, the protruding portions 514 and 516 extend continuously. The protruding portion 516, together with the protruding portion 515, functions as a positioning member for the elastic portion 50 in the Y-axis direction.

[0047] The protruding portion 515 extends from the other end portion in the Y-axis direction of the first surface 511 in the central portion in the Z-axis direction of the periphery of the clamping portion 51 (a region excluding both ends in the Z-axis direction of the periphery of the clamping portion 51). Note that the protruding portion 516 of one of the pair of clamping portions 51 is arranged at a position that does not overlap with the other protruding portion 515 in the X-axis direction (for example, on the side farther from the elastic portion 50 in the Y-axis direction than the protruding portion 515) in a state in which the pair of clamping portions 51 are arranged in the electricity storage device.

[0048] The protrusions 514 extend from one end of the periphery of the clamping portion 51 in the Y-axis direction to a midpoint in the Y-axis direction (for example, the center in the Y-axis direction) at both ends of the first surface 511. The protrusions 514 of each clamping portion 51 are arranged at positions such that the protrusions 514 of one clamping portion 51 and the protrusions 514 of the other clamping portion 51 do not overlap with each other in the X-axis direction when the pressure absorbing member 5 is placed in the electricity storage device (for example, the protrusions 514 of one clamping portion 51 are arranged at positions on the periphery of the other clamping portion 51 where no protrusions 514 are provided). The dimensions of the protrusions 514 in the X-axis direction are the same at each position in the Y-axis direction. The protrusions 514 provided at each end in the Z-axis direction all have the same shape. The protrusions 514 function as positioning members for the elastic portion 50 in the Z-axis direction.

[0049] Furthermore, the protrusions 514 and 516 function as stoppers that regulate the distance between the pair of clamping portions 51. The specific configuration of this stopper will be described below.

[0050] The clamping portion 51 has a first surface 511 that clamps the elastic portion, and a stopper surface 517 that is disposed at a predetermined distance from the first surface 511 on the opposite side of the elastic portion 50 in the X-axis direction. In this embodiment, the stopper surface 517 is a tip surface in the protruding direction (X-axis direction) of the protrusions 514, 516. The stopper surface 517 also extends along the Y-axis direction. Furthermore, when the elastic portion 50 is not elastically deformed, a gap is formed between the stopper surface 517 and the elastic portion 50 that is spaced apart in the X-axis direction (see FIG. 7A).

[0051] Furthermore, the distance between the pair of clamping portions 51 when the elastic portion 50 is not elastically deformed (specifically, the distance between the first surfaces 511 of the pair of clamping portions 51) is a first distance, and when the elastic portion 50 is elastically deformed, the distance can be changed from the first distance to a second distance (see FIG. 7B) that is smaller than the first distance. Specifically, the distance between the pair of clamping portions 51 can be changed until the stopper surface 517 (the tip surfaces of the protrusions 514, 516 in the X-axis direction) of one clamping portion 52 abuts against the first surface 511 of the other clamping portion 53. The dimension of the protrusions 514, 516 in the X-axis direction is equal to the second distance.

[0052] Furthermore, when the pressure absorbing member 5 is incorporated into the electricity storage device, a predetermined pressure is applied to the pressure absorbing member 5 in the X-axis direction, and therefore, even in an unused (brand new) electricity storage device, the distance between the pair of clamping portions 51 is smaller than the first distance.

[0053] The elastic portion 50 is made of a flexible elastic material such as a coil spring, a spring, or rubber. In this embodiment, the elastic portion 50 is, for example, a single rubber plate. The elastic portion 50 extends in the Y-axis direction and the Z-axis direction, which are orthogonal to the X-axis direction. The elastic portion 50 is shaped like a rectangular plate.

[0054] The elastic portion 50 has a first portion 500 and a second portion 501 that is arranged on the outside of the first portion 500 in the Y-axis direction, which is perpendicular to the X-axis direction, and the first portion 500 is more likely to elastically deform than the second portion 501. That is, the first portion 500, which is a region of the elastic portion 50 that overlaps with the center of the energy storage device 1 (the center in the Y-axis direction and the Z-axis direction) when viewed from the X-axis direction, is more likely to elastically deform than the second portion 501, which is a region located on the outside of the first portion 500.

[0055] In this embodiment, the elastic portion 50 is a combination of multiple elastic members made of different materials (see FIG. 6). Specifically, the first portion 500 of the elastic portion 50 is made of soft rubber, and the second portion 501 is made of hard rubber. This configuration also makes the first portion 500 more easily deformable than the second portion 501. Note that the entire elastic portion 50 may be a single elastic member made of the same material, for example, a single rubber plate.

[0056] In the elastic part 50, the first part 500 is disposed in the center in the Y-axis direction and extends over the entire area in the Z-axis direction. The second parts 501 are disposed at both ends in the Y-axis direction and extend over the entire area in the Z-axis direction. This allows the elastic part 50 to accommodate two different stacking loads. That is, the center in the Y-axis direction can accommodate a low load, and both ends in the Y-axis direction can accommodate a high load.

[0057] In the elastic portion 50, the first portion 500 may be disposed at the center in the Z-axis direction and extend over the entire area in the Y-axis direction, in which case the second portion 501 may be disposed at both ends in the Z-axis direction and extend over the entire area in the Y-axis direction. In addition, in the elastic portion 50, the first portion 500 may be disposed at the center in the Y-axis direction and at the center in the Z-axis direction, and the second portion 501 may be disposed in a ring shape so as to surround the first portion 500.

[0058] The spacer 2 has insulating properties (see FIGS. 1 and 4). The spacer 2 has a base adjacent to the case 10 (first wall 100c of the trunk portion 100b) of the energy storage device 1, and a restricting portion that prevents the energy storage device 1 adjacent to the base from shifting in position.

[0059] The spacers 2 will be described in more detail. The energy storage device includes two types of spacers 2 (2A, 2B) (see FIG. 4). That is, the energy storage device includes, as spacers 2, spacers 2 (hereinafter referred to as internal spacers) 2A that are arranged between two energy storage elements 1 or between an energy storage element 1 and a pressure absorbing member 5, and spacers (hereinafter referred to as external spacers) 2B that are adjacent to the outermost energy storage element 1 among the multiple energy storage elements 1.

[0060] As described above, the energy storage device according to this embodiment includes a plurality of energy storage elements 1, and therefore, the inner spacers 2A are disposed between adjacent energy storage elements 1. That is, the energy storage device includes a plurality of inner spacers 2A.

[0061] First, we will explain the internal spacer 2A arranged between two adjacent energy storage elements 1. The internal spacer 2A arranged between two adjacent energy storage elements 1 and the internal spacer 2A arranged between an adjacent energy storage element 1 and the pressure absorbing member 5 are the same member (same configuration), and the internal spacer 2A arranged between two adjacent energy storage elements 1 will be specifically explained below.

[0062] As shown in FIG. 5, the internal spacer 2A has a base 20A adjacent to the energy storage device 1 (first wall 100c of case body 100).

[0063] The base 20A of the internal spacer 2A is sandwiched between the two energy storage elements 1. Therefore, the base 20A of the internal spacer 2A has a first surface facing one of the two adjacent energy storage elements 1, and a second surface opposite the first surface facing the other of the two energy storage elements 1.

[0064] The base 20A of the internal spacer 2A has a first end arranged at a position corresponding to the cover plate 101 of the energy storage device 1, and a second end opposite the first end arranged at a position corresponding to the closing portion 100a of the energy storage device 1. The base 20A of the internal spacer 2A also has a third end arranged at a position corresponding to one second wall 100d of the energy storage device 1, and a fourth end opposite the third end arranged at a position corresponding to the other second wall 100d of the energy storage device 1.

[0065] The first and second ends of the base 20A of the internal spacer 2A extend in the Y-axis direction. The third and fourth ends of the base 20A of the internal spacer 2A extend in the Z-axis direction. Therefore, the base 20A of the internal spacer 2A is formed in a substantially rectangular shape. The base 20A of the internal spacer 2A is formed to have substantially the same size as the first wall 100c of the energy storage element 1.

[0066] In the energy storage device according to this embodiment, a ventilation passage (flow path) for passing a fluid (temperature-regulating fluid) is formed between the first surface of the base 20A of the internal spacer 2A and the energy storage element 1, or between the second surface of the base 20A of the internal spacer 2A and the energy storage element 1. The internal spacer 2A arranged between the energy storage element 1 and the pressure absorbing member 5 forms a flow path through which a fluid can flow between the internal spacer 2A and the pressure absorbing member 5. In this embodiment, the internal spacer 2A arranged between the energy storage element 1 and the pressure absorbing member 5 can be the same part as the internal spacer 2A arranged between the energy storage elements 1, and therefore an increase in the number of types of parts can be suppressed.

[0067] In the energy storage device 1 according to this embodiment, the base 20A of the internal spacer 2A is formed in a rectangular waveform. More specifically, the base 20A of the internal spacer 2A has a plurality of first contact portions 200A that contact only one of two adjacent energy storage devices 1, a plurality of second contact portions 201A that contact only the other of the two adjacent energy storage devices 1, and a plurality of connecting portions 202A that connect the first contact portions 200A and the second contact portions 201A.

[0068] The first contact portions 200A and the second contact portions 201A are alternately arranged in the Z-axis direction, and one end of the first contact portion 200A in the Z-axis direction and the other end of the second contact portion 201A in the Z-axis direction are connected by a connecting portion 202A. As a result, in the energy storage device, ventilation paths are formed between the first surface of the base 20A of the internal spacer 2A and the energy storage element 1, and between the second surface of the base 20A of the internal spacer 2A and the energy storage element 1.

[0069] Next, the outer spacer 2B will be described. The outer spacer 2B has a base (hereinafter simply referred to as the base) 20B having a first surface facing the energy storage device 1 (first wall 100c of the case body 100) and a second surface opposite to the first surface.

[0070] Furthermore, in the outer spacer 2B according to this embodiment, the base 20B faces an end member 30 (described later) of the holding member 3. That is, the outer spacer 2B is disposed between the energy storage device 1 and the end member 30.

[0071] The base 20B of the outer spacer 2B extends in the Y-axis direction and the Z-axis direction, which are orthogonal to the X-axis direction. That is, the base 20B is formed in a plate shape.

[0072] A ventilation passage for allowing a fluid to pass between the first surface of the base 20B and the energy storage device 1 is formed on the first surface of the base 20B of the outer spacer 2B.

[0073] As described above, the external spacer 2B according to this embodiment is disposed adjacent to the internal spacer via the energy storage element 1. That is, the energy storage device includes a pair of external spacers 2B. The external spacer 2B is adjacent to the endmost energy storage element 1 among the multiple energy storage elements 1. That is, the external spacers 2B are provided as a pair so as to sandwich the aligned multiple energy storage elements 1 therebetween.

[0074] In this embodiment, the holding member 3 is made of metal. As shown in Fig. 4, the holding member 3 includes a pair of end members 30 disposed adjacent to each outer spacer 2B, and a pair of extension members 31 connecting the pair of end members 30.

[0075] Each of the pair of end members 30 has a first surface facing the outer spacer 2B and a second surface opposite the first surface. Each of the pair of end members 30 has a pressure contact portion 300 that abuts against the outer spacer 2B.

[0076] The end plate 30 is made of metal and has a shape corresponding to that of the energy storage device 1 when viewed in the X-axis direction.

[0077] Each extension member 31 has connecting portions 310, 311 extending between the pair of end members 30. Each extension member 31 has a fixing portion 313 connected to the end member 30.

[0078] The connecting portions 310 and 311 are arranged at varying intervals in the Z-axis direction. Each of the connecting portions 310 and 311 has a first end in the longitudinal direction and a second end opposite to the first end.

[0079] Each of the first connecting portions 310, 311 is bent along the longitudinal direction. One of the portions of each of the first connecting portions 310, 311, separated by the bent portion, is positioned corresponding to the cover plate 101 of the energy storage device 1. The other of the first connecting portions 310, 311, separated by the bent portion, is positioned corresponding to the second wall 100d of the energy storage device 1.

[0080] The fixed portion 313 has linking portions 313a and 313b that connect the ends of the connecting portions 310 and 311 that are arranged at an interval in the Z-axis direction.

[0081] The insulators 4 have a shape corresponding to each of the extension members 31. The insulators 4 are disposed between each of the extension members 31 and the plurality of energy storage elements 1 to insulate them from one another.

[0082] According to the above energy storage device, the pressure absorbing members arranged between adjacent energy storage elements 1 elastically deform when a force is applied from outside in the X-axis direction, so that when the energy storage elements 1 expand, the pressure absorbing members 5 can absorb the force caused by the expansion. This suppresses deformation of the extension members 31 caused by the expansion of the energy storage elements 1.

[0083] Specifically, in this energy storage device, a pressure absorbing member 5 composed of a pair of clamping portions 51 and an elastic portion 50 sandwiched therebetween is disposed between adjacent energy storage elements 1, and when a force is applied to the pair of clamping portions 51 from outside in the X-axis direction in the pressure absorbing member 5, the elastic portions 50 elastically deform, so that when the energy storage elements 1 expand, the pressure absorbing member 5 can absorb the force caused by the expansion. This suppresses deformation of the extension member 31 caused by the expansion of the energy storage elements 1. In particular, deformation of the extension member 31 at a portion adjacent to the elastic portion 50 is suppressed.

[0084] Furthermore, in the above-described pressure absorbing member 5, when the pressure absorbing member 5 is arranged between the energy storage elements 1 so that the arrangement direction (X-axis direction) of the clamping portions 51 coincides with the stacking direction of the energy storage elements 1, the elastic portions 50 elastically deform when a force is applied to the pair of clamping portions 51 from the outside in the X-axis direction, and therefore, when the energy storage elements 1 expand, the pressure absorbing member 5 can absorb the force caused by the expansion. As a result, for example, in an energy storage device in which a plurality of energy storage elements 1 are fixed in a stacked state by extension members 31, when the pressure absorbing member 5 is arranged so that the arrangement direction of the energy storage elements 1 coincides with the arrangement direction of the clamping portions 51, deformation of the extension members 31 caused by the expansion of the energy storage elements 1 is suppressed.

[0085] Furthermore, in the energy storage device of this embodiment, the external dimensions of the pressure absorbing member 5 are the same as those of the energy storage elements 1, so the pressure absorbing member 5 can be placed in the energy storage device where the energy storage elements 1 can be placed; that is, it can be placed in place of the energy storage elements. Furthermore, because the pressure absorbing member 5 has such a size, the pressure absorbing member 5 can be replaced with any of the energy storage elements 1 currently held by the extension members 31, so that a configuration can be achieved in which the expansion of the energy storage elements 1 can be absorbed without changing the design of the energy storage device. In other words, without providing a separate structure for absorbing the expansion of the energy storage elements 1, that is, without changing the design of the energy storage device, simply by replacing the energy storage elements 1 with the pressure absorbing member 5, it is possible to absorb the increase in pressure in the X-axis direction caused by expansion of the energy storage elements 1 due to deterioration over time or the like.

[0086] Furthermore, in the energy storage device of this embodiment, when the energy storage element 1 expands during use, the amount of expansion is greater at the center of the energy storage element 1. Therefore, in the elastic portion 50, the thickness of the first portion 500 is made smaller than the thickness of the second portion 501, and the ease of elastic deformation is changed between the first portion of the pressure absorption member 5 that overlaps with the center of the energy storage element 1 and the outer second portion, so that when the energy storage element 1 expands, the force can be received by the entire pressure absorption member 5.

[0087] In the energy storage device of this embodiment, even if a force due to expansion of the energy storage element 1 or the like is applied to a part of the clamping portion 51 (plate-shaped member) of the pressure absorbing member 5, the plate-shaped clamping portion 51 has sufficient rigidity (the rigidity of the clamping portion 51 is greater than the rigidity of the elastic portion 50), and therefore the force is transmitted to the elastic portion 50 in a state where it is spread over the entire clamping portion 51, and the pressure absorbing member 5 can effectively mitigate this force.

[0088] Furthermore, in the electricity storage device of this embodiment, the pair of clamping portions 51 are members of the same shape, so that the number of types of parts can be reduced.

[0089] Furthermore, in the energy storage device of this embodiment, when a force in the X-axis direction is applied to each clamping portion 51, the contact portion of one clamping portion 52 comes into contact with the other clamping portion 53, thereby preventing the clamping portions 51 from getting closer to each other, and thereby preventing the elastic portion 50 from being crushed too much.

[0090] 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 spirit and scope of the present invention.

[0091] For example, the electricity storage device has one pressure absorbing member 5, but may have multiple pressure absorbing members 5. Also, the pressure absorbing member 5 is disposed at the center of the electricity storage device in the X-axis direction, but may be disposed in a location other than this.

[0092] Furthermore, although the outer dimensions of the pressure absorbing member 5 are the same as those of the energy storage device 1 in the above embodiment, they do not have to be the same as those of the energy storage device 1 as long as they can be accommodated in the extension member 31 .

[0093] In the above embodiment, the power storage device includes the pressure absorbing member 5, but may include an elastic member 6 that is elastically deformable in the X-axis direction instead of the pressure absorbing member 5. Modified examples of the shape of such elastic member 6 will be described below.

[0094] For example, as shown in Figures 8A and 8B, the elastic member 6 may be formed so that a portion thereof can be cut off. Specifically, the elastic member 6 may have a cut line 60. In this case, as shown in Figure 8C, a portion of the elastic member 6 (for example, a central portion aligned with the central portion of the energy storage element 1 that is prone to swell) may be cut off before being incorporated into the energy storage device. For example, a plurality of cut lines 60 are arranged in a substantially concentric pattern with the center of the elastic member 6 as the center point. The cut line 60 is, for example, a slit that is partially connected in the circumferential direction, but may also be, for example, a half cut, etc.

[0095] The outer dimensions of the elastic member 6 may be the same as those of the energy storage element 1. In this case, the elastic member 6 can be placed in a location in the energy storage device where the energy storage element 1 can be placed, that is, it can be placed in place of the energy storage element 1. Furthermore, the energy storage element 1 may have a rectangular shape.

[0096] 9A and 9B, the elastic member 6 may have a first portion 61 and a second portion 62 arranged on the outside of the first portion 61 in a direction perpendicular to the X-axis direction, and the first portion 61 may be more elastically deformable than the second portion 62. For example, the elastic member 6 may have, in a part (for example, the first portion 61), a through-hole 63 penetrating in the X-axis direction or a recess 64 recessed towards the outside of the power storage device in the X-axis direction.

[0097] In this configuration, the elastic member 6 is provided with the through holes 63 and recesses 64, thereby adjusting the ease of elastic deformation in the X-axis direction between the portion where the through holes 63 and recesses 64 are provided (e.g., first portion 61) and the other portion (e.g., second portion 62). Therefore, when the energy storage device 1 expands, the elastic member 6 can effectively absorb the force caused by the expansion, thereby suppressing deformation of the elongated member 31 caused by the expansion of the energy storage device 1.

[0098] In the above embodiment, the base 20A of the internal spacer 2A has a substantially rectangular shape and is approximately the same size as the first wall 100c of the energy storage element 1. However, the base 20A of the internal spacer 2A is not limited to being approximately rectangular, nor is it limited to being approximately the same size as the first wall 100c of the energy storage element 1, as long as it can correspond to the postures of two adjacent energy storage elements 1.

[0099] In the above embodiment, the internal spacer 2A was arranged between the pressure absorbing member 5 and the energy storage element 1, but it does not have to be arranged between the pressure absorbing member 5 and the energy storage element 1 as long as the surface of the pressure absorbing member 5 is made of an insulating material such as resin or rubber. [Explanation of symbols]

[0100] 1...energy storage element, 2...spacer (adjacent member), 2A...internal spacer, 2B...external spacer, 3...holding member, 4...insulator, 5...pressure absorbing member, 6...elastic member, 10...case, 11...external terminal, 20A, 20B...base, 21...case, 30...termination member, 31...extension member, 50...elastic portion, 51, 52, 53...clamping portion, 60...cut line, 61...first portion, 62...second portion, 63...through hole, 64...recess, 100...case body, 100a...blocking portion, 100 b...body portion, 100c...first wall, 100d...second wall, 101...cover plate, 101a...gas release valve, 102...battery cell, 140...end plate, 143...connecting bar, 200A...first abutment portion, 201A...second abutment portion, 202A...connecting portion, 310, 311...connecting portion, 313...fixing portion, 313a, 313b...connecting portion, 500...first portion, 501...second portion, 511...first surface, 512...second surface, 513...fixing portion, 514, 515, 516...protruding portion, 517...stopper surface

Claims

1. A plurality of storage elements arranged in a first direction; a pair of extension members extending in the first direction and sandwiching the plurality of energy storage elements from both sides in a second direction perpendicular to the first direction; a pressure absorbing member at least a portion of which is elastically deformable in the first direction; an adjacent member adjacent to the pressure absorbing member in the first direction, the pressure absorbing member and the adjacent member are disposed between adjacent energy storage elements, The electricity storage device, wherein the adjacent member forms a flow path between the adjacent member and the pressure absorbing member, through which a fluid can flow.

2. 2. The electricity storage device according to claim 1, wherein the pressure absorbing member has the same outer dimensions as the electricity storage element.

3. A plurality of storage elements arranged in a first direction; a pair of extension members extending in the first direction and sandwiching the plurality of energy storage elements from both sides in a second direction perpendicular to the first direction; a pressure absorbing member at least a portion of which is elastically deformable in the first direction; an adjacent member adjacent to the pressure absorbing member in the first direction, the pressure absorbing member and the adjacent member are disposed between adjacent energy storage elements, the pressure absorbing member has an elastic portion that is elastically deformable in the first direction, and a pair of clamping portions that sandwich the elastic portion from both sides in the first direction and are capable of transmitting a force applied from the outside to the elastic portion in the first direction, The energy storage element has a rectangular shape, the elastic portion has a first portion and a second portion disposed on an outer side of the first portion in a direction perpendicular to the first direction, The power storage device, wherein the first portion is more easily elastically deformable than the second portion.

4. each of the pair of clamping portions is a plate-shaped member extending in a direction perpendicular to the first direction, The power storage device according to claim 3 , wherein the rigidity of each of the pair of clamping portions is greater than the rigidity of the elastic portion.

5. 5. The power storage device according to claim 3, wherein one clamping portion and the other clamping portion of the pair of clamping portions are members having the same shape.

6. one of the pair of clamping portions has an abutment portion extending toward the other of the pair of clamping portions, The power storage device according to any one of claims 3 to 5, wherein a gap is formed between the contact portion and the other clamping portion when the elastic portion is not elastically deformed.

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