Power storage device

Abstract

To provide a power storage device capable of suppressing generation of thermal chains in the power storage element.SOLUTION: A power storage device 10 has a power storage unit 100 having a plurality of storage elements 110 lined up in a first direction and an outer body 120 housing the plurality of storage elements 110, and a support member 220 being disposed in a second direction intersecting the first direction of the power storage unit 100 and supporting the power storage unit 100 from below, and the support member 220 has a first support portion 222 disposed at a distance from an end portion of the power storage unit 100 in a third direction intersecting the first and second directions.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to an energy storage device including an energy storage unit having a plurality of energy storage elements and an exterior body that houses the plurality of energy storage elements. [Background technology]

[0002] Conventionally, there has been widely known an energy storage device that includes an energy storage unit having a plurality of energy storage elements and an exterior body that houses the plurality of energy storage elements, and that is configured such that the energy storage unit is supported from below by a support member. For example, Patent Document 1 discloses a battery module (energy storage device) in which a configuration (energy storage unit) in which a plurality of secondary batteries (energy storage elements) are housed in a case (exterior body) is supported from below by a base plate (support member). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2015-141765 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-mentioned conventionally configured energy storage device, the support member is disposed in contact with the energy storage unit, and therefore, when the energy storage element in the energy storage unit overheats, the heat is transferred to the other surrounding energy storage elements via the support member, which may cause a thermal chain reaction of the energy storage elements. For example, in the energy storage device disclosed in the above-mentioned Patent Document 1, the support member (base plate) is provided with a large number of fins extending in the width direction of the energy storage unit, and the energy storage unit is placed and supported on these fins. Therefore, when the energy storage element in the energy storage unit overheats, the exterior body that houses the energy storage element melts, and heat is transferred to the other surrounding energy storage elements via the fins, which may cause a thermal chain reaction of the energy storage elements.

[0005] The present invention was made by the inventors of the present application by focusing on the above-mentioned problem, and has an object to provide an electricity storage device that can suppress the occurrence of thermal chain reaction of electricity storage elements. [Means for solving the problem]

[0006] In order to achieve the above-mentioned object, an energy storage device according to one embodiment of the present invention comprises an energy storage unit having a plurality of energy storage elements arranged in a first direction and an exterior body that houses the plurality of energy storage elements, and a support member arranged in a second direction intersecting the first direction of the energy storage unit and supporting the energy storage unit from below, wherein the support member has a first support portion arranged at a distance from an end of the energy storage unit in a third direction intersecting the first direction and the second direction.

[0007] According to this, the energy storage device includes a support member that supports the energy storage unit from below in the second direction of the energy storage unit having a plurality of energy storage elements and an exterior body arranged in the first direction, and the support member has a first support portion that is arranged at a distance from the end of the energy storage unit in the third direction. Here, the inventor of the present application found that if the first support portion abuts against the end of the energy storage unit in the third direction, when the energy storage element overheats, the end of the exterior body in the third direction melts, and the melting of the exterior body may spread in the first direction via the first support portion that abuts against the end. When the heat of melting the exterior body spreads in the first direction (the arrangement direction of the plurality of energy storage elements), the heat is transmitted to other surrounding energy storage elements, and there is a risk of a thermal chain reaction of the energy storage elements occurring. For this reason, the first support portion of the support member is arranged at a distance from the end of the energy storage unit in the third direction. As a result, even if the storage element overheats and the end portion in the third direction of the outer casing of the storage unit melts, the melting of the outer casing is prevented from spreading in the first direction, thereby preventing a thermal chain reaction from occurring in the storage element.

[0008] The support member may further include a plate-shaped portion disposed in the second direction of the power storage unit, facing the power storage unit and spaced apart from the power storage unit.

[0009] According to this, by arranging the plate-shaped portion in the support member in the second direction of the energy storage unit while being spaced from the energy storage unit, even if the energy storage element overheats and the exterior body melts, the melting of the exterior body is prevented from spreading in the first direction. In other words, if the plate-shaped portion abuts against a portion where the exterior body is melted, the melting of the exterior body may spread in the first direction, but since the plate-shaped portion is arranged spaced from the exterior body, the melting of the exterior body is prevented from spreading in the first direction. This prevents the heat from the melting of the exterior body from being transferred to other energy storage elements, thereby preventing a thermal chain reaction of the energy storage elements.

[0010] The first support portion may be disposed so as to extend from one end to the other end of the energy storage unit in the first direction.

[0011] According to this, the first support portion of the support member extends from one end to the other end in the first direction of the energy storage unit, thereby making it possible to stably support the energy storage unit while suppressing the occurrence of thermal chain reaction of the energy storage elements.

[0012] The energy storage unit may have a shape that is elongated in the first direction, and the support member may further include a second support portion that supports an end portion of the energy storage unit in the first direction.

[0013] According to this, since the energy storage unit has a shape elongated in the first direction, it is possible to suppress the melting of the exterior body from spreading in the longitudinal direction of the energy storage unit. Also, since the support member has a second support portion that supports the end portion of the energy storage unit in the longitudinal direction (first direction), it is possible to stably support the energy storage unit. As a result, it is possible to stably support the energy storage unit while suppressing the occurrence of thermal chain reaction of the energy storage elements.

[0014] The exterior body may be made of resin.

[0015] According to this, since the exterior body of the energy storage unit is made of resin, the exterior body is likely to melt when the energy storage element overheats, and therefore, in the conventional configuration, thermal chain reaction of the energy storage element is likely to occur. In contrast, with the configuration of the present invention, even if the exterior body melts, the melting of the exterior body is prevented from spreading, and therefore, even if the exterior body is made of resin, the occurrence of thermal chain reaction of the energy storage element can be prevented.

[0016] The present invention can be realized not only as such an electricity storage device, but also as a support member. Effect of the Invention

[0017] According to the electricity storage device of the present invention, it is possible to suppress the occurrence of thermal chain reaction in the electricity storage elements. [Brief description of the drawings]

[0018] [Figure 1] 1 is a perspective view showing a configuration of an electricity storage device according to an embodiment; [Diagram 2] FIG. 2 is a perspective view showing a configuration of an electricity storage unit according to the embodiment. [Diagram 3] FIG. 2 is a perspective view showing a configuration of an energy storage element according to an embodiment. [Figure 4] FIG. 2 is a perspective view showing a configuration of a support member according to the embodiment. [Diagram 5] 5 is a perspective view showing a positional relationship between a support member and an electricity storage unit according to the embodiment. FIG. [Figure 6] 13 is a perspective view showing a configuration of a support member according to a first modified example of the embodiment, and a positional relationship between the support member and an electricity storage unit. FIG. [Figure 7] 13 is a perspective view showing a configuration of a support member according to a second modification of the embodiment, and a positional relationship between the support member and an electricity storage unit. FIG. [Figure 8] 13 is a perspective view showing a configuration of a support member according to a third modification of the embodiment, and a positional relationship between the support member and an electricity storage unit. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Hereinafter, a description will be given of an energy storage device according to an embodiment (including modified examples) of the present invention with reference to the drawings. Note that the embodiments described below are all comprehensive or specific examples. The numerical values, shapes, materials, components, the arrangement and connection forms of the components, manufacturing processes, and the order of the manufacturing processes shown in the following embodiments are merely examples and are not intended to limit the present invention. Each figure is a schematic diagram, and the dimensions are not necessarily strictly shown. In each figure, the same or similar components are given the same reference numerals.

[0020] In the following description and drawings, the width direction of the rack, the arrangement direction of the power storage units on the support members (shelf boards) of the rack, the facing direction of the long sides of the power storage units, or the facing direction of the short sides of the power storage elements are defined as the X-axis direction. The depth direction of the rack, the facing direction of the short sides of the power storage units (longitudinal direction of the power storage units), the arrangement direction of the power storage elements in one power storage unit, or the facing direction of the long sides of the power storage elements are defined as the Y-axis direction. The height direction of the rack, the arrangement direction of the power storage units sandwiching the support members, the arrangement direction of the power storage units and the support members, or the up-down direction are defined as the Z-axis direction. The X-axis, Y-axis, and Z-axis directions intersect with each other (orthogonal in this embodiment).

[0021] In the following description, for example, the positive X-axis direction indicates the direction of the X-axis arrow, and the negative X-axis direction indicates the opposite direction to the positive X-axis direction. The same applies to the Y-axis and Z-axis directions. Hereinafter, the Y-axis direction may also be referred to as the first direction, the Z-axis direction (or the negative Z-axis direction) may also be referred to as the second direction, and the X-axis direction may also be referred to as the third direction. Expressions indicating relative directions or attitudes, such as parallel and perpendicular, may also include cases where the directions or attitudes are not strictly those. For example, two directions being perpendicular to each other not only means that the two directions are completely perpendicular to each other, but also means that the two directions are substantially perpendicular to each other, that is, includes a difference of, for example, about several percent.

[0022] (Embodiment) [1 General Description of Power Storage Device 10] First, a general description of the energy storage device 10 according to the present embodiment will be given. Fig. 1 is a perspective view showing the configuration of the energy storage device 10 according to the present embodiment. In Fig. 1, a part of a rack 200 of the energy storage device 10 is seen through, and a part of the inside of the rack 200 is shown by a broken line. Fig. 2 is a perspective view showing the configuration of the energy storage unit 100 according to the present embodiment. In Fig. 2, the inside of the exterior body 120 of the energy storage unit 100 is shown by a broken line, and the inside of the exterior body 120 is shown by a broken line.

[0023] The power storage device 10 is a device that can charge electricity from an external source and discharge electricity to the outside, and has a rectangular parallelepiped shape in this embodiment. The power storage device 10 is used for power storage purposes or power supply purposes. Specifically, the power storage device 10 is used as a stationary battery or the like used in home or industrial power storage facilities. In this embodiment, the power storage device 10 is a stationary storage battery panel that stores power generated by wind power generation, solar power generation, or the like and stably supplies power to external facilities. The power storage device 10 can also be used as a battery for driving or starting an engine of a moving object such as an automobile, a motorcycle, a watercraft, a ship, a snowmobile, an agricultural machine, a construction machine, or a railway vehicle for an electric railway. Examples of the above-mentioned automobiles include an electric vehicle (EV), a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), and a gasoline vehicle. Examples of the above-mentioned railway vehicle for an electric railway include a train, a monorail, a linear motor car, and a hybrid train equipped with both a diesel engine and an electric motor.

[0024] 1, the energy storage device 10 includes an energy storage unit 100 and a rack 200 that houses the energy storage unit 100. In this embodiment, in the rack 200, three energy storage units 100 aligned in the X-axis direction are arranged in four stages in the Z-axis direction.

[0025] The energy storage unit 100 is a battery module (battery assembly) having a rectangular parallelepiped shape that is elongated in the Y-axis direction (first direction). As shown in Fig. 2, the energy storage unit 100 has a plurality of energy storage elements 110 arranged in the Y-axis direction (first direction), and an exterior body 120 that houses the plurality of energy storage elements 110. The number of energy storage elements 110 that the energy storage unit 100 has is not particularly limited, and for example, 16 energy storage elements 110 are arranged in the Y-axis direction and housed in the exterior body 120. In addition to these configurations, the energy storage unit 100 also has bus bars and the like that connect electrode terminals of the plurality of energy storage elements 110, but these are not shown in the drawings and will not be described in detail. The energy storage unit 100 may also include spacers arranged between the energy storage elements 110, restraining members (end plates, side plates, etc.) that restrain the energy storage elements 110, a bus bar frame that positions the bus bars, and electrical equipment such as circuit boards and relays for monitoring the charging and discharging states of the energy storage elements 110, but these are not illustrated or described.

[0026] The energy storage element 110 is a secondary battery (single cell) capable of charging and discharging electricity, and more specifically, a non-aqueous electrolyte secondary battery such as a lithium ion secondary battery. The energy storage element 110 has a flattened rectangular parallelepiped shape (corner shape). The shape of the energy storage element 110 is not limited to a rectangular parallelepiped shape, and may be a polygonal column shape, a cylindrical shape, an elongated cylindrical shape, or the like other than a rectangular parallelepiped shape. The energy storage element 110 is not limited to a non-aqueous electrolyte secondary battery, and may be a secondary battery other than a non-aqueous electrolyte secondary battery, or may be a capacitor. The energy storage element 110 may not be a secondary battery, but may be a primary battery that can use stored electricity without the user having to charge it. The energy storage element 110 may be a pouch-type energy storage element. A detailed description of the configuration of the energy storage element 110 will be given later.

[0027] The exterior body 120 is a box-shaped (rectangular parallelepiped) container (module case) that is elongated in the Y-axis direction and constitutes the exterior body of the energy storage unit 100. The exterior body 120 is disposed outside the multiple energy storage elements 110, fixes the multiple energy storage elements 110 in predetermined positions, and protects them from impacts and the like. There are no particular limitations on the material of the exterior body 120, but in this embodiment, the exterior body 120 is formed from a member that melts (burns) due to heat, specifically, resin. For example, the exterior body 120 is formed from an insulating resin member such as polycarbonate (PC), polypropylene (PP), polyethylene (PE), polystyrene (PS), polyphenylene sulfide resin (PPS), polyphenylene ether (PPE (including modified PPE)), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyether ether ketone (PEEK), tetrafluoroethylene perfluoroalkyl vinyl ether (PFA), polytetrafluoroethylene (PTFE), polyether sulfone (PES), ABS resin, or a composite material thereof. The exterior body 120 thereby prevents the multiple energy storage elements 110 from coming into contact with external metal members, etc.

[0028] The exterior body 120 has an exterior body main body 121 constituting the main body of the exterior body 120, and an exterior body lid body 122 constituting the lid body of the exterior body 120. The exterior body main body 121 is a bottomed rectangular cylindrical housing (casing) with an opening formed therein, and houses the energy storage element 110 and the like. The exterior body main body 121 is a bottomed rectangular cylindrical housing (casing) with an opening formed facing the Z-axis positive direction, and houses the energy storage element 110 and the like. That is, the exterior body main body 121 has a pair of opposing rectangular and flat long side wall parts on both sides in the X-axis direction, a pair of opposing rectangular and flat short side wall parts on both sides in the Y-axis direction, and a rectangular and flat bottom wall part on the Z-axis negative direction side. The exterior body lid body 122 is a flat rectangular member extending in the Y-axis direction that closes the opening of the exterior body main body 121. Exterior cover 122 engages or fits with exterior body 121 and is joined by adhesive, heat sealing, ultrasonic welding, etc. Exterior 120 is provided with external terminals (positive external terminal and negative external terminal) for charging with electricity from the outside and discharging electricity to the outside, but these are omitted from the illustration.

[0029] The rack 200 is a container (shelf) having a rectangular parallelepiped (box-shaped) shape, and includes a rack main body 210 in which a plurality of power storage units 100 are stored, and a support member 220 that supports the plurality of power storage units 100. The rack 200 (the rack main body 210 and the support member 220) are formed of a metal such as stainless steel, aluminum, an aluminum alloy, iron, or a plated steel plate. The rack 200 may be formed of any resin or the like that can be used for the exterior body 120 described above, but the rack main body 210 is preferably formed of a material with high strength, and the support member 220 is preferably formed of a material with high strength and heat resistance.

[0030] The rack main body 210 has a shape in which the surface (front surface) on the Y-axis negative direction side is open. That is, the rack main body 210 has two side surfaces 211, an upper surface 212, a bottom surface 213, a rear surface 214, and a partition 215. The rack main body 210 may have a cover member (door) that closes the opening on the surface (front surface) on the Y-axis negative direction side in an openable / closable manner (openable / closable).

[0031] The two side surface parts 211 are flat, rectangular wall parts disposed on both sides of the rack main body part 210 in the X-axis direction. The top surface part 212 is a flat, rectangular wall part disposed on the Z-axis positive direction side of the rack main body part 210. The bottom surface part 213 is a flat, rectangular wall part disposed on the Z-axis negative direction side of the rack main body part 210. The back surface part 214 is a flat, rectangular wall part disposed on the Y-axis positive direction side of the rack main body part 210. The back surface part 214 may be a cover member (door) that closes an opening on the surface (back surface) on the Y-axis positive direction side of the rack main body part 210 in an openable / closable manner (openable / closable). The partition part 215 is a flat, rectangular wall part that separates the storage space 230 in which the power storage unit 100 is accommodated from the storage space 240 in which equipment other than the power storage unit 100, such as a control device, is accommodated.

[0032] The support member 220 is a flat rectangular shelf plate arranged in the negative Z-axis direction (second direction intersecting with the first direction) of the power storage unit 100 and supporting the power storage unit 100 from below (negative Z-axis direction). In this embodiment, a plurality of (four) support members 220 parallel to the XY plane are arranged side by side in the Z-axis direction to divide the space inside the rack main body 210. As a result, four storage spaces 230 arranged side by side in the Z-axis direction are formed inside the rack main body 210. The storage space 230 is a rectangular parallelepiped space in which one or more power storage units 100 (three power storage units 100 in this embodiment) are stored. That is, the rack 200 has four storage spaces 230, and three power storage units 100 are stored in each of the four storage spaces 230. In other words, the three power storage units 100 are placed on the four support members 220, respectively. The configuration of the support member 220 will be described in detail later.

[0033] [2. Description of the Configuration of Energy Storage Element 110] Next, the configuration of the energy storage element 110 will be described in detail. Since all the energy storage elements 110 in the energy storage unit 100 have the same configuration, the configuration of one energy storage element 110 will be described in detail below. Fig. 3 is a perspective view showing the configuration of an energy storage element 110 according to this embodiment.

[0034] As shown in FIG. 3, the energy storage element 110 includes a container 111 and a pair of electrode terminals 114 (positive and negative terminals). Inside the container 111, an electrode body, a current collector (positive and negative current collectors), an electrolyte (non-aqueous electrolyte), and the like are contained, but these are not shown. The type of electrolyte is not particularly limited as long as it does not impair the performance of the energy storage element 110, and various electrolytes can be selected. Between the container 111 (container lid 113 described below) and the electrode terminal 114, and between the container 111 (container lid 113) and the current collectors, gaskets and the like are arranged to improve insulation and airtightness, but these are also not shown. A spacer may be arranged on the side of the current collector, or an insulating sheet covering the outer surface of the container 111 may be arranged.

[0035] Container 111 is a rectangular parallelepiped (corner-shaped) container having container body 112 with an opening formed therein, and container lid 113 that closes the opening of container body 112. The material of container 111 is not particularly limited, but is preferably a weldable metal such as stainless steel, aluminum, aluminum alloy, iron, or plated steel sheet.

[0036] The container body 112 is a rectangular cylindrical member having a bottom, which constitutes the main body of the container 111. The container body 112 has a pair of opposing rectangular and planar long side portions on both sides in the Y-axis direction, a pair of opposing rectangular and planar short side portions on both sides in the X-axis direction, and a rectangular and planar bottom portion on the Z-axis minus direction side. The container lid 113 is a flat and rectangular member which constitutes the lid of the container 111, and is disposed in the Z-axis plus direction of the container body 112, extending in the X-axis direction. The container lid 113 is provided with a gas exhaust valve 115 which releases pressure when the pressure inside the container 111 rises. The container 111 (for example, the container lid 113) may also be provided with a liquid injection portion for injecting an electrolyte into the container 111.

[0037] The electrode terminals 114 are terminals (positive and negative terminals) of the energy storage element 110 disposed on the container lid 113 of the container 111, and are electrically connected to the positive and negative plates of the electrode body via current collectors. In other words, the electrode terminals 114 are metal members for conducting electricity stored in the electrode body to the external space of the energy storage element 110 and for introducing electricity into the internal space of the energy storage element 110 to store electricity in the electrode body. The electrode terminals 114 are formed of aluminum, an aluminum alloy, copper, a copper alloy, or the like.

[0038] The electrode body is an electricity storage element (power generating element) formed by stacking a positive electrode plate, a negative electrode plate, and a separator. The positive electrode plate of the electrode body is a positive electrode active material layer formed on a positive electrode base material layer which is a current collector foil made of a metal such as aluminum or an aluminum alloy. The negative electrode plate is a negative electrode active material layer formed on a negative electrode base material layer which is a current collector foil made of a metal such as copper or a copper alloy. As the positive electrode active material used in the positive electrode active material layer and the negative electrode active material used in the negative electrode active material layer, any suitable known material can be used as long as it can absorb and release lithium ions. The separator is a microporous sheet, and any suitable known material such as resin can be used. The electrode body may be a stack type electrode body formed by stacking a plurality of flat electrode plates (positive electrode plates and negative electrode plates), a bellows type electrode body in which the electrode plates are folded in a bellows shape, or a wound type electrode body formed by winding the electrode plates.

[0039] The current collectors are conductive members (positive and negative current collectors) electrically connected to the electrode terminal 114 and the electrode body. The positive current collector is made of aluminum or an aluminum alloy, similar to the positive electrode base layer of the positive electrode plate, and the negative current collector is made of copper or a copper alloy, similar to the negative electrode base layer of the negative electrode plate.

[0040] [3. Description of the Configuration of Support Member 220] Next, the configuration of the support member 220 will be described in detail. Fig. 4 is a perspective view showing the configuration of the support member 220 according to this embodiment. Since all the support members 220 of the rack 200 have the same configuration, Fig. 4 shows the configuration of one support member 220. Fig. 5 is a perspective view showing the positional relationship between the support member 220 according to this embodiment and the power storage unit 100. Specifically, Fig. 5 shows a state in which the power storage unit 100 is placed on the support member 220 at a portion on the positive side of the X-axis of the support member 220.

[0041] The support member 220 is a member that supports multiple (three in this embodiment) energy storage units 100 from below, and has a plate-shaped portion 221, a first support portion 222, and a second support portion 223, as shown in Figures 4 and 5.

[0042] The plate-shaped portion 221 is a flat rectangular portion parallel to the XY plane, and is disposed in the negative Z-axis direction (second direction) of the power storage unit 100, facing the power storage unit 100 and spaced apart from the power storage unit 100. Specifically, the plate-shaped portion 221 is disposed in the Z-axis direction next to the multiple (three) power storage units 100 at an interval. The plate-shaped portion 221 is also disposed so as to extend in the X-axis direction across the multiple power storage units 100, and to extend in the Y-axis direction from one end (one edge) to the other end (the other edge) of the multiple power storage units 100 in the Y-axis direction. As a result, the plate-shaped portion 221 is disposed so as to cover the entire multiple power storage units 100 when viewed from the negative Z-axis direction (second direction).

[0043] The first support portion 222 is a flat, rectangular portion parallel to the YZ plane that protrudes from the plate-shaped portion 221 in the positive direction of the Z axis and extends in the Y axis direction from one end to the other end of the plate-shaped portion 221. In the present embodiment, three first support portions 222 are arranged on both sides in the X axis direction and at the center of the plate-shaped portion 221 in correspondence with the three electricity storage units 100. The first support portion 222 may be joined to the plate-shaped portion 221 (and the second support portion 223) by welding, fitting, engagement, bolt fastening, adhesion, melting, or the like, or may be formed integrally with the plate-shaped portion 221 (and the second support portion 223) by casting, forging, press processing, or the like.

[0044] Each first support portion 222 is disposed in the center of the power storage unit 100 in the X-axis direction and extends from one end to the other end in the Y-axis direction (first direction) of the power storage unit 100. The first support portion 222 is disposed in the negative Z-axis direction of the power storage unit 100, and supports the power storage unit 100 by placing it thereon in a state of contact with a surface of the power storage unit 100 in the negative Z-axis direction (a bottom wall portion of the exterior body 120). The surface (upper surface) of the first support portion 222 in the positive Z-axis direction is formed as a flat surface (horizontal surface), and the power storage unit 100 is placed and supported in a state of contact with the flat surface.

[0045] In this manner, the first support portion 222 is disposed apart from the end portion in the X-axis direction of the power storage unit 100 (a third direction intersecting the first and second directions). That is, the first support portion 222 is disposed at a position not overlapping with the end portion in the X-axis direction of the power storage unit 100 when viewed from the Z-axis direction. The end portion in the X-axis direction is, for example, a region located at an end portion when the width in the X-axis direction of the power storage unit 100 (exterior body 120) is divided into thirds. The end portion in the X-axis direction is more preferably a region located at an end portion when the width in the X-axis direction of the power storage unit 100 (exterior body 120) is divided into fifths, and even more preferably a region located at an end portion when the width in the X-axis direction of the power storage unit 100 (exterior body 120) is divided into ten equal parts.

[0046] The second support portion 223 is a flat rectangular portion parallel to the XZ plane that protrudes from the plate-like portion 221 in the positive direction of the Z axis and extends in the X axis direction from one end (one edge) to the other end (the other edge) of the plate-like portion 221 in the X axis direction. Specifically, two second support portions 223 that protrude in the positive direction of the Z axis from both edges of the plate-like portion 221 in the Y axis direction are disposed at both ends of the plate-like portion 221 in the Y axis direction. The two second support portions 223 are disposed at positions sandwiching the three first support portions 222 in the Y axis direction and connected to both ends of the three first support portions 222.

[0047] In this embodiment, the second support portion 223 is connected to the plate-shaped portion 221 and is formed integrally with the plate-shaped portion 221 (integrally formed). For example, the plate-shaped portion 221 and the second support portion 223 can be formed by bending an end portion of a single flat plate-shaped member. The second support portion 223 may be integrally formed with the plate-shaped portion 221 (and the first support portion 222) by casting, forging, press processing, or the like. The second support portion 223 may be formed separately from the plate-shaped portion 221 and joined to the plate-shaped portion 221 (and the first support portion 222) by welding, fitting, engagement, bolt fastening, adhesion, melting, or the like.

[0048] The second support portion 223 supports an end portion of the energy storage unit 100 in the Y-axis direction (first direction). That is, at both ends in the Y-axis direction of the plurality (three) of energy storage units 100, two second support portions 223 are arranged extending in the X-axis direction across the plurality of energy storage units 100, and support both ends in the Y-axis direction of the plurality of energy storage units 100. The second support portion 223 is arranged in the negative Z-axis direction of the energy storage unit 100, and supports the energy storage unit 100 by placing it thereon in a state of abutting against a surface (bottom wall portion of the exterior body 120) of the energy storage unit 100 in the negative Z-axis direction. The surface (upper surface) of the second support portion 223 in the positive Z-axis direction is formed as a flat surface (horizontal surface), and the energy storage unit 100 is placed and supported in a state of abutting against the flat surface.

[0049] In this way, the two second support parts 223 are disposed at positions overlapping both end parts (both end edges) of the energy storage unit 100 in the Y axis direction as viewed from the Z axis direction. Since the first support part 222 is disposed between the two second support parts 223, the first support part 222 supports a part different from the end part of the energy storage unit 100 in the Y axis direction as viewed from the Z axis direction. In other words, the first support part 222 abuts against a part different from the edge of the energy storage unit 100 (exterior body 120) in the Y axis direction and supports the part different from the edge.

[0050] [4. Description of Effects] As described above, the energy storage device 10 according to the embodiment of the present invention includes a support member 220 that supports the energy storage unit 100 from below in the second direction (negative Z-axis direction) of the energy storage unit 100 having a plurality of energy storage elements 110 and an exterior body 120 arranged in a first direction (Y-axis direction). The support member 220 has a first support portion 222 that is disposed apart from an end portion of the energy storage unit 100 in the third direction (X-axis direction). Here, the inventors of the present application have found that if the first support portion 222 is in contact with the end portion of the energy storage unit 100 in the third direction, when the energy storage elements 110 overheat, the end portion of the exterior body 120 in the third direction may melt, and the melting of the exterior body 120 may spread in the first direction via the first support portion 222 that is in contact with the end portion. When the heat of melting of the exterior body 120 spreads in the first direction (the arrangement direction of the multiple energy storage elements 110), the heat is transferred to other surrounding energy storage elements 110, which may cause a thermal chain reaction of the energy storage elements 110. For this reason, the first support portion 222 of the support member 220 is disposed away from the end portion in the third direction of the energy storage unit 100. As a result, even if the energy storage element 110 overheats and the end portion in the third direction of the exterior body 120 of the energy storage unit 100 melts, the melting of the exterior body 120 is prevented from spreading in the first direction, and therefore, the occurrence of a thermal chain reaction of the energy storage elements 110 can be prevented.

[0051] In the support member 220, by arranging the plate-shaped portion 221 in the second direction of the energy storage unit 100 while being spaced from the energy storage unit 100, even if the energy storage element 110 overheats and the exterior body 120 melts, the melting of the exterior body 120 is suppressed from spreading in the first direction. In other words, if the plate-shaped portion 221 abuts against a portion where the exterior body 120 has melted, the melting of the exterior body 120 may spread in the first direction, but since the plate-shaped portion 221 is arranged spaced from the exterior body 120, the melting of the exterior body 120 is suppressed from spreading in the first direction. This suppresses the heat of melting of the exterior body 120 from being transferred to other energy storage elements 110, and thus the occurrence of a thermal chain reaction of the energy storage elements 110 can be suppressed. Furthermore, even if the melted material of exterior body 120 falls from exterior body 120, it remains on plate-shaped portion 221, and thus thermal chain reaction to other power storage units 100 below the power storage unit 100 can be suppressed.

[0052] By having the first support portion 222 of the support member 220 extend from one end to the other end in the first direction of the energy storage unit 100, the energy storage unit 100 can be stably supported while suppressing the occurrence of thermal chain reaction of the energy storage elements 110.

[0053] By arranging first support portion 222 at a position that does not overlap with the end portion in the third direction of energy storage unit 100 when viewed from the second direction, even if the end portion in the third direction of exterior body 120 melts, the molten material is prevented from falling onto first support portion 222. This prevents melting of exterior body 120 from spreading in the first direction, and thus prevents thermal chain reaction of energy storage element 110.

[0054] The first support portion 222 supports the energy storage unit 100 other than the end portion in the first direction. In other words, by arranging another support portion (second support portion 223) that supports the end portion in the third direction at the end portion in the first direction of the energy storage unit 100, the energy storage unit 100 can be stably supported.

[0055] The energy storage unit 100 has a shape that is elongated in the first direction, which can suppress the melting of the exterior body 120 from spreading in the longitudinal direction of the energy storage unit 100. Furthermore, the support member 220 has the second support portion 223 that supports the end portion of the energy storage unit 100 in the longitudinal direction (first direction), which can stably support the energy storage unit 100. As a result, the energy storage unit 100 can be stably supported while suppressing the occurrence of thermal chain reaction of the energy storage elements 110.

[0056] Because the exterior body 120 of the energy storage unit 100 is made of resin, the exterior body 120 is likely to melt when the energy storage element 110 overheats, and therefore, in the conventional configuration, thermal chain reaction is likely to occur in the energy storage element 110. In contrast, the configuration of the present embodiment prevents the melting of the exterior body 120 from spreading even when the exterior body 120 melts, and therefore, it is possible to prevent thermal chain reaction of the energy storage element 110 from occurring even when the exterior body 120 is made of resin.

[0057] [5. Explanation of Variations] (Variation 1) Next, a first modification of the above embodiment will be described. Fig. 6 is a perspective view showing a configuration of a support member 220a according to the first modification of the present embodiment, and a positional relationship between the support member 220a and the electricity storage unit 100. Specifically, Fig. 6 is a view corresponding to Fig. 5.

[0058] 6, a support member 220a in this modification has a first support portion 222a instead of the first support portion 222 of the support member 220 in the above embodiment. The other configurations are similar to those in the above embodiment, so detailed description will be omitted.

[0059] The first support portion 222a is a columnar portion protruding in the positive direction of the Z axis from the center in the Y axis direction of the plate-shaped portion 221. In this modification, three first support portions 222a are arranged at the center in the X axis direction and the center in the Y axis direction of the power storage units 100 corresponding to the three power storage units 100. The first support portion 222a may be joined to the plate-shaped portion 221 by welding, fitting, engagement, bolt fastening, adhesion, melting, or the like, or may be formed integrally with the plate-shaped portion 221 by casting, forging, press processing, or the like.

[0060] Each of the first support portions 222a is disposed at a center in the X-axis direction and a center in the Y-axis direction of the power storage unit 100 in the negative Z-axis direction, and supports the power storage unit 100 by placing it thereon in contact with a surface of the power storage unit 100 in the negative Z-axis direction (a bottom wall portion of the exterior body 120). The surface (upper surface) of the first support portion 222a in the positive Z-axis direction is formed as a flat surface (horizontal surface), and the power storage unit 100 is placed and supported in contact with the flat surface. In this manner, the first support portion 222a is disposed away from an end portion of the power storage unit 100 in the X-axis direction (third direction).

[0061] As described above, the energy storage device according to this modification can achieve the same effects as those of the above embodiment. As described above, the first support portion 222a only needs to be disposed apart from the end portion in the X-axis direction of the energy storage unit 100, and the position and shape of the first support portion 222a are not particularly limited. Note that, in this modification, the first support portion 222a may be disposed at a position shifted from the center portion in the X-axis direction and the center portion in the Y-axis direction of the energy storage unit 100, and may have a shape other than a cylindrical shape, such as a tubular shape such as an oval cylinder shape, an elliptical cylinder shape, a rectangular cylinder shape, or a cylindrical shape, or a hollow shape.

[0062] (Variation 2) Next, a second modification of the above embodiment will be described. Fig. 7 is a perspective view showing a configuration of a support member 220b according to the second modification of the present embodiment, and a positional relationship between the support member 220b and the electricity storage unit 100. Specifically, Fig. 7 is a view corresponding to Fig. 5.

[0063] 7, a support member 220b in this modification has a first support portion 222b instead of the first support portion 222 of the support member 220 in the above embodiment. The other configurations are similar to those in the above embodiment, so detailed description will be omitted.

[0064] The first support portion 222b is a flat rectangular portion parallel to the XZ plane, protruding from a center portion in the Y-axis direction of the plate-shaped portion 221 in the positive Z-axis direction and extending in the X-axis direction from one end (one edge) to the other end (the other edge) of the plate-shaped portion 221 in the X-axis direction. In this modification, the first support portion 222b is disposed at the center portion in the Y-axis direction of the plurality (three) of power storage units 100, extending in the X-axis direction across the plurality of power storage units 100, and supports the center portions in the Y-axis direction of the plurality of power storage units 100. The first support portion 222b is disposed at the center portion in the Y-axis direction of the power storage unit 100 in the negative Z-axis direction, and supports the power storage unit 100 by placing it thereon in a state of abutting against a surface of the power storage unit 100 in the negative Z-axis direction (the bottom wall portion of the exterior body 120). The first support portion 222b has a surface (upper surface) in the positive direction of the Z axis formed as a flat surface (horizontal surface), and the electricity storage unit 100 is placed and supported in a state of being in contact with the flat surface.

[0065] The first support portion 222b has a recess 224 recessed in the negative Z-axis direction at a position facing the end portion of the power storage unit 100 in the X-axis direction. In this modification, the recess 224 is a recess recessed in a semicircular shape when viewed from the Y-axis direction. Thus, the first support portion 222b is disposed at a position overlapping with the end portion of the power storage unit 100 in the X-axis direction when viewed from the Z-axis direction, but is disposed apart from the end portion of the power storage unit 100 in the X-axis direction. The first support portion 222b may be joined to the plate-shaped portion 221 by welding, fitting, engagement, bolt fastening, adhesion, welding, or the like, or may be formed integrally with the plate-shaped portion 221 by casting, forging, press processing, or the like.

[0066] As described above, the energy storage device according to this modification can achieve the same effects as those of the above embodiment. As described above, the first support portion 222b only needs to be disposed apart from the end portion in the X-axis direction of the energy storage unit 100, and the position and shape of the first support portion 222b are not particularly limited. In this modification, the shape of the recess 224 of the first support portion 222b is not particularly limited, and may be a shape other than a semicircular shape, such as a semi-oval shape, a semi-elliptical shape, a rectangular shape, a triangular shape, or another polygonal shape, as viewed from the Y-axis direction. The first support portion 222b may be divided into three parts and disposed in correspondence with the three energy storage units 100.

[0067] (Variation 3) Next, a third modification of the above embodiment will be described. Fig. 8 is a perspective view showing a configuration of a support member 220c according to the third modification of the present embodiment, and a positional relationship between the support member 220c and the electricity storage unit 100. Specifically, Fig. 8 is a view corresponding to Fig. 5.

[0068] 8, a support member 220c in this modification has a first support portion 222c instead of the first support portion 222 and the second support portion 223 of the support member 220 in the above embodiment. The other configurations are similar to those in the above embodiment, so detailed description will be omitted.

[0069] The first support portion 222c is an inverted U-shaped portion as viewed from the Y-axis direction, which protrudes from the plate-shaped portion 221 in the positive direction of the Z-axis and extends from one end (one edge) of the plate-shaped portion 221 in the Y-axis direction to the other end (the other edge) of the plate-shaped portion 221 in the Y-axis direction. That is, the first support portion 222c has a shape in which a surface in the negative direction of the Z-axis of a rectangular parallelepiped prism extending in the Y-axis direction is recessed in a rectangular shape in the positive direction of the Z-axis. In this modification, two first support portions 222c aligned in the X-axis direction are disposed for each power storage unit 100. The first support portion 222c may be joined to the plate-shaped portion 221 by welding, fitting, engagement, bolt fastening, adhesion, welding, or the like, or may be integrally formed with the plate-shaped portion 221 by casting, forging, or the like.

[0070] Each of the first support portions 222c is disposed at a position avoiding an end portion of the power storage unit 100 in the X-axis direction and extending from one end portion to the other end portion in the Y-axis direction (first direction) of the power storage unit 100. That is, the first support portions 222c are disposed apart from the end portion of the power storage unit 100 in the X-axis direction (third direction). The first support portions 222c are disposed in the negative Z-axis direction of the power storage unit 100, and support the power storage unit 100 by placing it thereon in a state of abutting against a surface of the power storage unit 100 in the negative Z-axis direction (a bottom wall portion of the exterior body 120). The surface (upper surface) of the first support portion 222c in the positive Z-axis direction is formed as a flat surface (horizontal surface), and the power storage unit 100 is placed and supported in a state of abutting against the flat surface.

[0071] As described above, the power storage device according to this modification can achieve the same effect as the above embodiment. In particular, in this modification, the support member 220c does not have the second support portion 223 that the support member 220 in the above embodiment has, but even with this configuration, the same effect as the above embodiment can be achieved. In this modification, the shape of the first support portion 222c is not particularly limited, and the face in the Z-axis positive direction may be concave, the other faces may be concave, or none of the faces may be concave, and the shape may be a semicircle, semi-oval, semi-ellipse, triangle, or other polygonal shape when viewed from the Y-axis direction. The number of first support portions 222c is also not particularly limited, and three or more first support portions 222c may be arranged in the X-axis direction, or one first support portion 222c with a large width in the X-axis direction may be arranged.

[0072] (Other variations) Although the power storage device according to the embodiment of the present invention (including its modified examples) has been described above, the present invention is not limited to this embodiment. The embodiment disclosed here is illustrative in all respects, and the scope of the present invention includes all modifications within the meaning and scope of the claims.

[0073] For example, in the above embodiment, the support member is disposed vertically below the energy storage unit 100 (second direction) and supports the energy storage unit 100 from below. However, the support member may be disposed in a direction slightly inclined from below the vertical direction of the energy storage unit 100 and supports the energy storage unit 100 from below. In other words, the second direction may be defined as a direction inclined from below the vertical direction.

[0074] In the above embodiment, the support member has the plate-shaped portion 221, but it is not essential that the support member has the plate-shaped portion 221.

[0075] In the above embodiment, the energy storage unit 100 has a shape elongated in the Y-axis direction, and the second support portion 223 supports an end portion of the energy storage unit 100 in the longitudinal direction. However, the energy storage unit 100 may have a shape elongated in the X-axis direction (a shape in which the Y-axis direction is short), and the second support portion 223 may support an end portion of the energy storage unit 100 in the lateral direction. Alternatively, the energy storage unit 100 may have a shape elongated in the Z-axis direction.

[0076] In the above embodiment, the rack 200 has a plurality of (four) support members, but the number of support members that the rack 200 has is not particularly limited, and the rack 200 may have only one support member. In addition, the support member is a member that supports a plurality of (three) power storage units 100, but the number of power storage units 100 supported by the support member is not particularly limited, and the support member may support only one power storage unit 100. In other words, the support member may have only a first support portion or the like that corresponds to one power storage unit 100.

[0077] In the above embodiment, all the support members of the rack 200 have the above configuration, but any of the support members may not have the above configuration. Also, one support member has the above configuration for all the power storage units 100, but any of the power storage units 100 may not have the above configuration.

[0078] In the above embodiment, the energy storage unit 100 is placed and supported in contact with the support member. However, the energy storage unit 100 may be placed in indirect contact with the support member via an insulating member or the like, rather than in direct contact with the support member. Even in this case, if the insulating member or the like is included in the support member, or if the insulating member or the like is defined as being included in the energy storage unit 100, the energy storage unit 100 will be placed in direct contact with the support member.

[0079] Any combination of the above-described embodiments and modifications is also included within the scope of the present invention.

[0080] The present invention can be realized not only as such an electricity storage device, but also as a support member. [Industrial Applicability]

[0081] The present invention can be applied to an electricity storage device including an electricity storage element such as a lithium ion secondary battery. [Explanation of symbols]

[0082] 10. Energy storage device 100 Energy Storage Unit 110 Energy storage element 111 Container 114 Electrode terminal 120 Exterior body 200 racks 210 Rack body 211 Side part 212 Top part 213 Bottom part 214 Back part 215 Partition 220, 220a, 220b, 220c Support members 221 Plate-shaped part 222, 222a, 222b, 222c First support part 223 Second support part 224 Recess 230, 240 Storage space

Claims

1. an energy storage unit including a plurality of energy storage elements arranged in a first direction and an exterior body that houses the plurality of energy storage elements; a rack that houses the power storage unit; the rack is arranged in a second direction intersecting the first direction of the power storage unit and includes a shelf plate supporting the power storage unit from below; The shelf board is a first support portion disposed apart from an end portion of the electricity storage unit in a third direction intersecting the first direction and the second direction; a plate-shaped portion disposed in the second direction of the power storage unit, facing the power storage unit and spaced apart from the power storage unit; Energy storage device.

2. an energy storage unit including a plurality of energy storage elements arranged in a first direction and an exterior body that houses the plurality of energy storage elements; a rack that houses the power storage unit; the rack is arranged in a second direction intersecting the first direction of the power storage unit and includes a shelf plate supporting the power storage unit from below; the shelf board has a first support portion arranged to be spaced apart from an end portion of the electricity storage unit in a third direction intersecting the first direction and the second direction, The first support portion is disposed at a position facing a center portion of the energy storage unit in the third direction. Energy storage device.

3. The first support portion is disposed to extend from one end portion to the other end portion of the electricity storage unit in the first direction. The power storage device according to claim 1 or 2.

4. The power storage unit has an elongated shape in the first direction, The shelf board further includes a second support portion that supports an end portion of the power storage unit in the first direction. The power storage device according to any one of claims 1 to 3.

5. The exterior body is formed of resin. The power storage device according to any one of claims 1 to 4.

Images