Power storage device

Abstract

This power storage device comprises: a power storage element; a spacer; a housing; and an intermediate member disposed between the spacer and the housing in a second direction that is a direction intersecting a first direction which is the direction in which the power storage element and the spacer are arranged. At least one of the spacer and the housing is provided with a protrusion that protrudes toward the intermediate member in the second direction and contacts the intermediate member.

Description

Power storage device

[0001] The present invention relates to an electricity storage device.

[0002] Patent Document 1 discloses a battery pack that is configured by arranging multiple batteries with separators sandwiched between them and that cool air is blown between the batteries to cool them, and that the separator has a cooling air flow path through which the cooling air passes between the separator and the flow path surface of the battery.

[0003] JP 2012-199044 A

[0004] In the battery pack disclosed in Patent Document 1, when the separator and batteries are housed in an exterior body, if a gap is formed between the separator and the exterior body, the amount of cooling air flowing through the separator's cooling air flow path may decrease, and the batteries may not be cooled effectively. For this reason, it may be desirable to prevent the formation of a gap between the separator and the exterior body. Even when not cooling the batteries, it may be desirable to prevent the formation of a gap between the separator and the exterior body when, for example, it is desirable to prevent the batteries and separator from moving within the exterior body.

[0005] The present invention was made by the inventor of the present application by focusing on the above-mentioned problem, and aims to provide an electricity storage device that can prevent gaps from occurring between the spacer and the outer casing.

[0006] A storage device according to one embodiment of the present invention comprises a storage element, a spacer, an outer casing, and an intermediate member arranged between the spacer and the outer casing in a second direction that intersects a first direction in which the storage element and the spacer are arranged, and at least one of the spacer and the outer casing has a protrusion that protrudes toward the intermediate member in the second direction and contacts the intermediate member.

[0007] According to the electricity storage device of the present invention, it is possible to prevent a gap from being generated between the spacer and the exterior body.

[0008] FIG. 1 is a perspective view showing a configuration of an energy storage device according to an embodiment. FIG. 2 is an exploded perspective view showing energy storage elements and a spacer of an energy storage unit included in the energy storage device according to the embodiment. FIG. 3 is a perspective view showing a configuration of energy storage elements according to the embodiment. FIG. 4 is a perspective view showing a configuration of a spacer according to the embodiment. FIG. 5 is a perspective view showing a configuration of a spacer according to the embodiment. FIG. 6 is a front view showing a configuration of a protrusion and a leg portion of a spacer according to the embodiment. FIG. 7 is a perspective view showing a configuration of an exterior body main body and an intermediate member according to the embodiment. FIG. 8 is a cross-sectional view showing a positional relationship between the exterior body main body and the intermediate member and the spacer according to the embodiment. FIG. 9 is a cross-sectional view showing a configuration around a protrusion of a spacer according to the embodiment. FIG. 10A is a cross-sectional view showing a state before the spacer according to the embodiment is arranged on the exterior body main body and the intermediate member. FIG. 10B is a cross-sectional view showing a state after the spacer according to the embodiment is arranged on the exterior body main body and the intermediate member. FIG. 11 is a cross-sectional view showing a protrusion included in an exterior body according to a first modified example of the embodiment and a configuration around the protrusion.

[0009] (1) An energy storage device according to one aspect of the present invention comprises an energy storage element, a spacer, an outer casing, and an intermediate member arranged between the spacer and the outer casing in a second direction that intersects a first direction in which the energy storage element and the spacer are arranged, and at least one of the spacer and the outer casing has a protrusion that protrudes toward the intermediate member in the second direction and contacts the intermediate member.

[0010] According to one aspect of the present invention, an energy storage device includes an intermediate member between a spacer and an outer casing. This intermediate member can prevent a gap from being generated between the spacer and the outer casing. Furthermore, at least one of the spacer and the outer casing includes a protrusion that protrudes toward the intermediate member and contacts the intermediate member. This allows the protrusion to contact the intermediate member, preventing a gap from being generated between the spacer and the outer casing, even if the distance between the spacer and the outer casing varies.

[0011] (2) In the energy storage device described in (1) above, the spacer may hold the energy storage element.

[0012] According to the energy storage device described in (2) above, it is possible to prevent a gap from being generated between the spacer that holds the energy storage element and the exterior body, which makes it possible to cool the energy storage element while the spacer holds it, and to prevent the energy storage element from moving within the exterior body.

[0013] (3) In the energy storage device described in (1) or (2) above, at least one of the spacer and the outer casing may have a plurality of the protrusions arranged in a third direction that intersects the first direction and the second direction.

[0014] According to the electricity storage device described in (3) above, at least one of the spacer and the exterior body is provided with a plurality of protrusions, and the plurality of protrusions can further prevent a gap from being generated between the spacer and the exterior body.

[0015] (4) In the energy storage device according to any one of (1) to (3) above, at least a portion of the protrusion may be embedded in the intermediate member.

[0016] According to the electricity storage device described in (4) above, at least a portion of the protrusion is embedded in the intermediate member, so that it is possible to more reliably prevent a gap from being generated between the spacer and the exterior body.

[0017] (5) In the energy storage device according to any one of (1) to (4) above, the intermediate member may be disposed between the spacer and a bottom portion of the exterior body.

[0018] According to the energy storage device described in (5) above, by disposing the intermediate member between the spacer and the bottom of the exterior body, it is possible to prevent a gap from being formed between the spacer and the bottom of the exterior body, thereby effectively cooling the energy storage elements when a coolant is caused to flow between the spacer and the bottom of the exterior body, and by stably disposing the spacer at the bottom of the exterior body, it is possible to prevent the spacer from moving inside the exterior body.

[0019] (6) In the energy storage device described in (5) above, the spacer may include a leg portion that contacts the bottom portion of the exterior body.

[0020] According to the energy storage device described in (6) above, the spacer has legs that contact the bottom of the exterior body, which further reduces the occurrence of a gap between the spacer and the bottom of the exterior body. The contact of the legs of the spacer with the bottom of the exterior body allows the spacer to be more stably positioned on the bottom of the exterior body.

[0021] (7) In the energy storage device according to any one of (1) to (6) above, the protrusion may extend in the first direction.

[0022] According to the energy storage device described in (7) above, the protrusions extend in the first direction (the direction in which the energy storage elements and the spacers are arranged), thereby preventing gaps from being formed between the spacers and the exterior body along the first direction, thereby enabling the energy storage elements to be effectively cooled when a refrigerant flows in the first direction, and enabling the spacers to be stably positioned on the exterior body in the first direction.

[0023] Hereinafter, with reference to the drawings, a description will be given of an energy storage device according to an embodiment of the present invention (including modifications thereof). The embodiments described below are all comprehensive or specific examples. The numerical values, shapes, materials, components, component placement and connection configurations, manufacturing processes, and the order of manufacturing processes shown in the following embodiments are examples and are not intended to limit the present invention. In each drawing, dimensions and the like are not strictly illustrated. In each drawing, the same or similar components are designated by the same reference numerals.

[0024] In the following description and drawings, the X-axis direction is defined as the short-side direction of the exterior body, the arrangement direction of a pair of terminals of the energy storage element, or the opposing direction of a pair of short side surfaces of the container for the energy storage element. The Y-axis direction is defined as the long-side direction of the exterior body, the arrangement direction of multiple energy storage elements or multiple spacers, the arrangement direction of the energy storage element and spacers, the thickness direction (flattening direction) of the energy storage element or spacer, or the opposing direction of a pair of long side surfaces of the container for the energy storage element. The Z-axis direction is defined as the protruding direction of the terminals of the energy storage element, the arrangement direction of the container body and the container lid of the energy storage element, the arrangement direction of the exterior body body and the lid of the exterior body, the opposing direction of the opening and bottom of the exterior body, the arrangement direction of the spacer, the intermediate member, and the bottom of the exterior body, or the up-down direction. The X-axis, Y-axis, and Z-axis directions intersect each other (orthogonal in this embodiment). Depending on the usage mode, the Z-axis may not be the up-down direction; however, for convenience of explanation, the Z-axis direction will be described below as the up-down direction.

[0025] In the following description, the positive X-axis direction refers to the direction of the X-axis arrow, and the negative X-axis direction refers to the direction opposite to the positive X-axis direction. Simply referring to the X-axis direction refers to both or either of the positive X-axis direction and the negative X-axis direction. The same applies to the Y-axis and Z-axis directions. Hereinafter, the Y-axis direction will also be referred to as the first direction, the Z-axis direction as the second direction, and the X-axis direction as the third direction. Expressions indicating relative directions or attitudes, such as parallel and perpendicular, also include cases where the directions or attitudes are not strictly the same. Two directions being parallel (or perpendicular) not only means that the two directions are completely parallel (or perpendicular), but also means that the directions are substantially parallel (or perpendicular), i.e., there is a difference of a few percent. In the following description, the term "insulating" means "electrically insulating." An insulating material has a volume resistivity of 1×10 ６ Ωm or more, more preferably 1×10 ７ Ωm or more, more preferably 1×10 １０ It is preferable that the material be made of a material with a resistance of Ωm or more.

[0026] (Embodiment) [1 Description of Energy Storage Device 1] First, a schematic configuration of the energy storage device 1 according to this embodiment will be described. FIG. 1 is a perspective view showing the configuration of the energy storage device 1 according to this embodiment. FIG. 1 shows the energy storage device 1 in a state where the lid 320 is removed from the exterior body main body 310 of the exterior body 300. As a result, FIG. 1 illustrates the energy storage unit 10 arranged inside the exterior body 300. FIG. 2 is an exploded perspective view showing the energy storage elements 100 and spacers 200 of the energy storage unit 10 included in the energy storage device 1 according to this embodiment. FIG. 2 disassembles the components included in the energy storage unit 10 and illustrates two energy storage elements 100 and three spacers 200 (two spacers 200a and one spacer 200b) located at the end of the energy storage unit 10 in the negative Y-axis direction.

[0027] The power storage device 1 is a device that can charge electricity from an external source and discharge electricity to an external source. The power storage device 1 is used for power storage purposes, power supply purposes, etc. The power storage device 1 is used as a battery for driving or starting the engine of a mobile object such as an automobile, a motorcycle, a personal watercraft, a ship, a snowmobile, an agricultural machine, a construction machine, an automatic guided vehicle (AGV), or a railway vehicle for an electric railway. Examples of the automobile include an electric vehicle (EV), a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), and a fossil fuel (gasoline, diesel, liquefied natural gas, etc.) vehicle. Examples of the railway vehicle for the 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. The power storage device 1 can also be used as a stationary battery for home or business use.

[0028] 1 , the energy storage device 1 includes an energy storage unit 10 and an exterior body 300 that houses the energy storage unit 10. The energy storage device 1 also includes external terminals (a positive electrode external terminal and a negative electrode external terminal) for electrically connecting to an external device, but these are not shown or described here. In addition to the above components, the energy storage device 1 may also include electrical devices such as a circuit board and a relay that monitor or control the charge state and discharge state of the energy storage unit 10.

[0029] The energy storage unit 10 is a battery module (battery assembly) including a plurality of energy storage elements 100. The energy storage unit 10 has a generally rectangular parallelepiped shape that is elongated in the Y-axis direction (first direction) by arranging the plurality of energy storage elements 100 and spacers 200 alternately in the Y-axis direction (first direction). The energy storage unit 10 includes a plurality of energy storage elements 100 and a plurality of spacers 200 (200a, 200b). The energy storage unit 10 also includes bus bars that connect the energy storage elements 100 in series or in parallel, a bus bar frame that holds the bus bars, and bus bars that connect the energy storage elements 100 to external terminals, but these are not shown in the drawings. The bus bars may connect all of the energy storage elements 100 in series, or may connect some of the energy storage elements 100 in parallel and then connect them in series, or may connect all of the energy storage elements 100 in parallel. The energy storage unit 10 is a non-constrained type module that does not include any restraining members (end plates, side plates, etc.) that restrain the plurality of energy storage elements 100 and spacers 200 in the Y-axis direction.

[0030] The energy storage element 100 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 100 has a rectangular parallelepiped shape (square or rectangular) that is flattened in the Y-axis direction. In this embodiment, a plurality of energy storage elements 100 are arranged side by side in the Y-axis direction. However, the number of arranged energy storage elements 100 is not particularly limited and may be one, several tens of energy storage elements 100, or more. The size and shape of the energy storage element 100 are also not particularly limited and may be an elongated cylinder, an elliptical cylinder, a cylindrical shape, a polygonal prism shape other than a rectangular parallelepiped, or the like. The energy storage element 100 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 100 may be a primary battery instead of a secondary battery. The energy storage element 100 may be a battery using a solid electrolyte. The energy storage element 100 may be a pouch-type energy storage element.

[0031] The spacer 200 is a flat member in the Y-axis direction that is arranged alongside the energy storage element 100 in the Y-axis direction and provides insulation and / or thermal insulation between the energy storage element 100 and other components. The spacer 200 is an insulating or thermal insulating plate that is arranged in the positive or negative Y-axis direction of the energy storage element 100 and provides insulation and / or thermal insulation between the energy storage elements 100 and each other or between the energy storage element 100 and the exterior body 300. The spacer 200 has wall portions on both sides of the energy storage element 100 in the X-axis direction and on both sides of the energy storage element 100 in the Z-axis direction, thereby functioning as a holder that holds the energy storage element 100 and positions the energy storage element 100. The spacer 200 has flow paths formed therein through which a refrigerant (a fluid such as air) flows, and also functions to cool the energy storage element 100.

[0032] The spacer 200 is formed from an insulating material 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), polyethersulfone (PES), polyamide (PA), ABS resin, or a composite material thereof, or a material having heat insulating properties such as mica.

[0033] Hereinafter, the spacers 200 arranged between the two energy storage elements 100 (spacers 200 other than those at both ends of the energy storage unit 10 in the Y-axis direction) will also be referred to as spacers 200a. The spacers 200 arranged at both ends of the energy storage unit 10 in the Y-axis direction (between the energy storage elements 100 at the ends and the exterior body 300) will also be referred to as spacers 200b. The spacers 200 (spacers 200a, 200b) are arranged alternately with the energy storage elements 100. While FIG. 2 shows a configuration in which two energy storage elements 100, two spacers 200a, and one spacer 200b are arranged alternately, the other spacers 200a and 200b are also arranged alternately with the energy storage elements 100.

[0034] Specifically, as shown in FIG. 2 , the spacer 200a is an intermediate spacer (intermediate holder, middle holder) having walls on both sides in the X-axis direction and on both sides in the Z-axis direction of two energy storage elements 100 arranged on both sides of the spacer 200a in the Y-axis direction, and holding the two energy storage elements 100. The spacer 200b is an end spacer (end holder) having walls on both sides in the X-axis direction and on both sides in the Z-axis direction of one energy storage element 100 arranged on one side of the spacer 200b in the Y-axis direction, and holding the one energy storage element 100. The energy storage element 100 located at the end of the energy storage unit 10 in the Y-axis direction is held by the spacer 200a and the spacer 200b. The other energy storage elements 100 are held by the two spacers 200a. In this way, the spacer 200a has a double-sided support configuration in which two energy storage elements 100 are supported on both sides in the Y-axis direction, while the spacer 200b has a single-sided support configuration in which one energy storage element 100 is supported on only one side in the Y-axis direction. The spacer 200a may hold one energy storage element 100 on each half of the spacer 200a in the Y-axis direction, or may hold one energy storage element 100 on only one side of the spacer 200a in the Y-axis direction. All the spacers 200 (spacers 200a, 200b) may be made of the same material, or any of the spacers 200 may be made of a different material.

[0035] In the present embodiment, all of the spacers 200 a and 200 b are connected or fixed together. Two of the spacers 200 b are fixed to the exterior body 300 (exterior body main body 310). In this way, the entire energy storage unit 10 is fixed to the exterior body 300.

[0036] The exterior body 300 is a container (case) having a substantially rectangular parallelepiped (box-shaped) shape that constitutes the exterior body (housing, outer shell) of the energy storage device 1. The exterior body 300 is disposed outside the energy storage unit 10, fixes the energy storage unit 10 in a predetermined position, and protects it from impacts and the like. The exterior body 300 is a metal case formed from a metal member such as aluminum, aluminum alloy, stainless steel, iron, or plated steel sheet. In this embodiment, the exterior body 300 is formed by aluminum die-casting (aluminum die-casting). The exterior body 300 may be formed from an insulating member such as any resin material that can be used for the spacer 200 included in the energy storage unit 10.

[0037] As shown in FIG. 1 , the exterior body 300 includes an exterior body main body 310 that constitutes the main body of the exterior body 300, and a lid body 320 that constitutes the lid body of the exterior body 300. The exterior body main body 310 is a housing (chassis) in which a first opening 310a is formed in the positive direction of the Z axis, and accommodates the energy storage unit 10 (the energy storage element 100 and the spacer 200 (spacers 200a and 200b)). The lid body 320 is a flat, rectangular member that closes the first opening 310a of the exterior body main body 310. The rectangular first opening 310a is formed in the exterior body main body 310, and after the energy storage unit 10 is inserted through the first opening 310a, the exterior body main body 310 and the lid body 320 are joined by screwing with bolts or the like, welding, adhesive, or the like. This results in the exterior body 300 having a structure in which the interior is sealed (sealed). A terminal block for external terminals (positive external terminal and negative external terminal) may be attached to the exterior body main body 310, the lid body 320, or the spacer 200 (200b), and the external terminals may be arranged on the terminal block.

[0038] Next, the configurations of the energy storage device 100, the spacer 200 (particularly, the spacer 200a), and the exterior body 300 (particularly, the exterior body main body 310) will be described in detail.

[0039] [1.1 Description of Energy Storage Element 100] Fig. 3 is a perspective view showing the configuration of the energy storage element 100 according to this embodiment. Fig. 3 shows an enlarged view of the energy storage element 100 shown in Fig. 2. Since the multiple energy storage elements 100 included in the energy storage unit 10 all have the same configuration, Fig. 3 shows one energy storage element 100, and the configuration of one energy storage element 100 will be described in detail below.

[0040] As shown in FIG. 3 , the energy storage element 100 includes a container 110 and a pair of terminals 140 (positive and negative electrodes). The container 110 contains an electrode assembly, a pair of current collectors (positive and negative electrodes), and an electrolyte (non-aqueous electrolyte). Gaskets are disposed between the terminals 140 and current collectors and the container 110, but these are not shown (the gaskets are only partially shown). The type of electrolyte is not particularly limited as long as it does not impair the performance of the energy storage element 100, and various types can be selected. The gasket may be made of any insulating material. In addition to the above components, the energy storage element 100 may also include spacers disposed on the sides of the electrode assembly, an insulating film encasing the electrode assembly, and an insulating film (such as a shrink tube) covering the outer surface of the container 110.

[0041] The container 110 is a rectangular parallelepiped (square or box-shaped) case including a container body 120 with an opening formed therein and a container lid 130 that closes the opening of the container body 120. The container body 120 is a rectangular cylindrical member with a bottom that constitutes the main body of the container 110, and has an opening formed on the positive side of the Z axis. The container lid 130 is a rectangular plate-like member that is elongated in the X axis direction and constitutes the lid of the container 110, and is disposed in the positive direction of the Z axis of the container body 120. The container lid 130 is provided with a gas exhaust valve 131 that releases pressure inside the container 110 if the pressure inside the container 110 increases excessively, a liquid injection portion (not shown) for injecting electrolyte into the container 110, and other components. The material of the container 110 (the container body 120 and the container lid 130) is not particularly limited and can be a weldable (joinable) metal such as stainless steel, aluminum, aluminum alloy, iron, or plated steel sheet, but resin can also be used.

[0042] After the electrode assembly and the like are housed inside the container body 120, the container body 120 and the container lid 130 are joined by welding or the like, thereby sealing the interior of the container 110. The container 110 has a pair of long sides 111 on both sides in the Y-axis direction, a pair of short sides 112 on both sides in the X-axis direction, and a bottom surface 113 in the negative Z-axis direction. The long sides 111 are rectangular flat portions that form the long sides of the container 110 and are arranged opposite adjacent spacers 200 in the Y-axis direction. The long sides 111 are adjacent to the short sides 112 and the bottom surface 113 and have a larger area than the short sides 112. The short sides 112 are rectangular flat portions that form the short sides of the container 110 and are arranged opposite the walls of the spacers 200 and the exterior body 300 in the X-axis direction. The short sides 112 are adjacent to the long sides 111 and the bottom surface 113 and have a smaller area than the long sides 111. The bottom surface 113 is a rectangular flat portion that forms the bottom surface of the container 110, and is arranged opposite the wall portion of the spacer 200 and the bottom portion of the exterior body 300 in the Z-axis direction. The bottom surface 113 is arranged adjacent to the long side surface 111 and the short side surface 112.

[0043] The terminals 140 are electrode terminals (positive and negative terminals) of the energy storage element 100 that are arranged on the container lid 130. The terminals 140 are arranged to protrude from the upper surface (terminal arrangement surface) of the container lid 130 in the positive direction of the Z axis. The terminals 140 are electrically connected to the positive and negative electrode plates of the electrode body via current collectors. The terminals 140 are metal members that conduct electricity stored in the electrode body to the external space of the energy storage element 100 and introduce electricity into the internal space of the energy storage element 100 to store electricity in the electrode body. The terminals 140 are formed from aluminum, an aluminum alloy, copper, a copper alloy, or the like.

[0044] The electrode assembly 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 is a positive electrode current collector foil, which is a metal foil made of a metal such as aluminum or an aluminum alloy, on which a positive electrode active material layer is formed. The negative electrode plate is a negative electrode current collector foil, which is a metal foil made of a metal such as copper or a copper alloy, on which a negative electrode active material layer is formed. Any known material capable of absorbing and releasing charge-transporting ions can be used as the active material for the positive electrode active material layer and the negative electrode active material layer. The separator can be a microporous resin sheet or nonwoven fabric. In this embodiment, the electrode assembly is formed by stacking electrode plates (positive electrode plates and negative electrode plates) in the Y-axis direction. The electrode assembly may be of any shape, such as a wound electrode assembly formed by winding electrode plates (positive electrode plates and negative electrode plates), a stacked electrode assembly formed by stacking multiple flat electrode plates, or a bellows-shaped electrode assembly formed by folding electrode plates in an accordion-like shape.

[0045] The current collectors are conductive current collecting members (positive and negative current collectors) electrically and mechanically connected to the terminal 140 and the electrode body. The positive current collector is made of aluminum, an aluminum alloy, or the like, similar to the positive current collector foil of the positive electrode plate of the electrode body, and the negative current collector is made of copper, a copper alloy, or the like, similar to the negative current collector foil of the negative electrode plate of the electrode body.

[0046] [1.2 Description of Spacer 200a] Next, the configuration of spacer 200a among spacers 200 will be described in detail. Because the multiple spacers 200a included in the energy storage unit 10 all have the same configuration, only one spacer 200a will be illustrated below, and the configuration of that single spacer 200a will be described in detail. FIGS. 4 and 5 are perspective views showing the configuration of spacer 200 (spacer 200a) according to this embodiment. FIG. 4 is an enlarged view of spacer 200a shown in FIG. 2, viewed obliquely from below. FIG. 5 shows the configuration of spacer 200a shown in FIG. 4 rotated 180° about a line passing through the center of spacer 200a and parallel to the Z-axis. FIG. 6 is a front view showing the configuration of protrusion 230 and leg portion 240 of spacer 200 (spacer 200a) according to this embodiment. FIG. 6 is an enlarged view of the configuration of the X-axis negative end of the Z-axis negative end of spacer 200a shown in FIG. 4, viewed from the Y-axis negative direction.

[0047] 4 and 5, the spacer 200a has a shape that is similar between the positive half of the spacer 200a in the X-axis direction and the negative half of the spacer 200a in the X-axis direction. The spacer 200a has a shape that is symmetrical with respect to a plane that passes through the center position and is parallel to the YZ plane. The spacer 200a includes a spacer body 210, a spacer wall 220, a pair of protrusions 230, and a pair of legs 240.

[0048] The spacer main body 210 is a flat, rectangular portion that constitutes the main body of the spacer 200a and is disposed parallel to the XZ plane. The spacer main body 210 is a portion that faces the energy storage elements 100 in the Y-axis direction (first direction), which is the alignment direction of the energy storage elements 100 and the spacer 200a. Specifically, the spacer main body 210 is disposed between the containers 110 of the two energy storage units 10 in the Y-axis direction. The spacer main body 210 is disposed in a state that faces the long side surface 111 of the container 110 of the energy storage element 100 in the Y-axis direction and is in contact with the long side surface 111 so as to cover the entire surface of the long side surface 111.

[0049] As shown in FIG. 5 , a plurality of protrusions 211 are provided on the surface of the spacer main body 210 in the positive direction of the Y axis. The plurality of protrusions 211 are ribs (L-shaped ribs) that extend in the positive direction of the Z axis from the negative end of the spacer main body 210, curve toward both sides in the X axis direction (the positive or negative X axis direction), and extend to both sides in the X axis direction (the positive or negative X axis direction). The plurality of protrusions 211 form a plurality of spaces 212 curved in an L shape. The plurality of spaces 212 extend in the positive direction of the Z axis from the negative end of the spacer main body 210, curve toward both sides in the X axis direction, and extend to both sides in the X axis direction. The plurality of spaces 212 are spaces that are disposed between the spacer main body 210 and the energy storage device 100 when the spacer 200a and the energy storage device 100 are assembled. The spaces 212 are flow paths for a coolant that flows between the spacer main body 210 and the energy storage device 100. The refrigerant flowing through the space 212 is a fluid, such as a gas such as air or a liquid, for cooling the energy storage element 100. The space 212 can also be used as a space into which a jig is inserted when holding the energy storage element 100 during manufacturing (assembly).

[0050] The spacer wall portions 220 are walls arranged at both ends in the Z-axis direction and both ends in the X-axis direction of the spacer main body 210. The spacer wall portions 220 are arranged on both sides in the Z-axis direction and both ends in the X-axis direction of the energy storage element 100, and cover the four corners of the energy storage element 100 located at both ends in the Z-axis direction and both ends in the X-axis direction of the energy storage element 100. This allows the spacer 200a to hold the energy storage element 100. Specifically, the spacer wall portions 220 include a first spacer wall portion 221, a second spacer wall portion 222, a third spacer wall portion 223, a fourth spacer wall portion 224, and a fifth spacer wall portion 225.

[0051] The first spacer wall portion 221 includes flat wall portions parallel to the XY plane that protrude toward both sides in the Y axis direction from both X axis direction ends of the spacer main body 210 in the positive Z axis direction. Specifically, the first spacer wall portion 221 protrudes in the positive Y axis direction from the surface of the spacer main body 210 in the positive Y axis direction, and protrudes in the negative Y axis direction from the surface of the spacer main body 210 in the negative Y axis direction. These wall portions of the first spacer wall portion 221 face the container lid portion 130 of the container 110 of the energy storage device 100 in the Z axis direction in the positive Z axis direction at both X axis direction ends of the energy storage device 100, and are arranged in contact with the container lid portion 130. The second spacer wall portion 222 includes wall portions that protrude in the positive Y axis direction from both X axis direction ends of the spacer main body 210 in the negative Z axis direction, and a wall portion that protrudes in the negative Y axis direction from the X axis direction center. These walls of the second spacer wall 222 are flat plate-like portions extending in the X-axis direction and arranged parallel to the XY plane. These walls of the second spacer wall 222 are arranged in the negative Z-axis direction of the energy storage device 100, facing the bottom surface 113 of the container 110 of the energy storage device 100 in the Z-axis direction and in contact with the bottom surface 113.

[0052] The third spacer wall portion 223 includes flat wall portions parallel to the YZ plane that protrude in both directions in the Y axis direction from the ends of both ends of the spacer body 210 in the positive Z axis direction in the X axis direction. Specifically, the third spacer wall portion 223 protrudes in the positive Y axis direction from the surface of the spacer body 210 in the positive Y axis direction, and protrudes in the negative Y axis direction from the surface of the spacer body 210 in the negative Y axis direction. These wall portions of the third spacer wall portion 223 face the short side surfaces 112 of the container 110 of the energy storage device 100 in the X axis direction, on both sides of the end of the energy storage device 100 in the positive Z axis direction, and are arranged in contact with the short side surfaces 112. The fourth spacer wall portion 224 includes flat wall portions parallel to the YZ plane that protrude in both directions in the Y axis direction from the ends of both ends of the spacer body 210 in the negative Z axis direction in the X axis direction. Specifically, the fourth spacer wall portion 224 protrudes in the positive Y-axis direction from the surface of the spacer body 210 facing the positive Y-axis direction, and protrudes in the negative Y-axis direction from the surface of the spacer body 210 facing the negative Y-axis direction. These wall portions of the fourth spacer wall portion 224 are arranged to face the short side surfaces 112 of the container 110 of the energy storage device 100 in the X-axis direction on both sides of the end of the energy storage device 100 facing the negative Z-axis direction, and to be in contact with the short side surfaces 112.

[0053] With this configuration, the spacer 200 a holds the energy storage device 100 with the first spacer wall portion 221 , the second spacer wall portion 222 , the third spacer wall portion 223 and the fourth spacer wall portion 224 .

[0054] The fifth spacer wall portion 225 includes flat wall portions parallel to the XY plane that protrude in the negative Y-axis direction from both X-axis direction ends of the negative Z-axis end of the spacer main body 210. These wall portions of the fifth spacer wall portion 225 face the bottom surface 113 of the container 110 of the energy storage device 100 in the negative Z-axis direction of the energy storage device 100 in the Z-axis direction, and are spaced apart from the bottom surface 113. These wall portions of the fifth spacer wall portion 225 are located on both sides of the wall portion of the second spacer wall portion 222 that protrudes in the negative Y-axis direction, and protrude in the negative Z-axis direction from the wall portion of the second spacer wall portion 222. A pair of protrusions 230 and a pair of legs 240 are arranged on these wall portions of the fifth spacer wall portion 225. A pair of protrusions 230 and a pair of legs 240 are arranged on both X-axis direction ends of the negative Z-axis end of the spacer 200a.

[0055] As shown in FIGS. 4 to 6 , the protrusion 230 is a long protrusion (convex portion) that protrudes from the fifth spacer wall portion 225 in the negative Z-axis direction and extends in the Y-axis direction (first direction). In this embodiment, the protrusion 230 is a rectangular parallelepiped (rod-shaped) portion that is rectangular when viewed in the Y-axis direction. The protrusion 230 is continuously formed from one end of the fifth spacer wall portion 225 to the other end in the Y-axis direction. As a result, among the multiple protrusions 230 provided on the multiple spacers 200a of the energy storage unit 10, adjacent protrusions 230 are arranged in close proximity or contact with each other in the Y-axis direction, and the multiple protrusions 230 are linearly aligned in the Y-axis direction. Two (pairs) of protrusions 230 aligned in the X-axis direction are arranged for two (pairs) of wall portions of the fifth spacer wall portion 225 aligned in the X-axis direction. In this way, the spacer 200a includes multiple protrusions 230 aligned in the X-axis direction (a third direction intersecting the first and second directions).

[0056] The leg portion 240 is a long protrusion (convex portion) that protrudes from the fifth spacer wall portion 225 in the negative Z-axis direction and extends in the Y-axis direction (first direction). The leg portion 240 also protrudes from the fifth spacer wall portion 225 in the positive Y-axis direction. The multiple legs 240 included in the multiple spacers 200a of the energy storage unit 10 are arranged so as to be aligned linearly in the Y-axis direction. The leg portion 240 protrudes in the negative Z-axis direction beyond the protrusion 230. Two (a pair) of legs 240 aligned in the X-axis direction are arranged relative to two (a pair) of walls aligned in the X-axis direction included in the fifth spacer wall portion 225. In this manner, the spacer 200a includes multiple legs 240 aligned in the X-axis direction (third direction). In the present embodiment, the legs 240 are arranged outside the protrusion 230 in the X-axis direction. In the X-axis direction, two (a pair) of protrusions 230 are arranged between two (a pair) of leg portions 240. The leg portions 240 are legs of the spacer 200a, and are placed on (in contact with) step portions 311a of a bottom portion 311 of the exterior body 300 (described later), thereby supporting the spacer 200a relative to the exterior body 300. The shape, size, etc. of the leg portions 240 are not particularly limited as long as they are configured to support the spacer 200a.

[0057] In this embodiment, the two protrusions 230 and the two leg portions 240 are integrally formed (molded integrally, integrated) with other parts of the spacer 200a, but at least one of the two protrusions 230 and the two leg portions 240 may be configured separately from other parts of the spacer 200a.

[0058] [1.3 Description of the Exterior Body Main Body 310 and the Surrounding Configuration of the Protrusion 230] Next, the configuration of the exterior body main body 310 included in the exterior body 300 and the surrounding configuration of the protrusion 230 of the spacer 200a will be described in detail. FIG. 7 is a perspective view showing the configuration of the exterior body main body 310 and the intermediate member 400 according to the present embodiment. FIG. 8 is a cross-sectional view showing the positional relationship between the exterior body main body 310, the intermediate member 400, and the spacer 200a according to the present embodiment. FIG. 8 shows a cross-section of a configuration in which the intermediate member 400 and the spacer 200a are arranged on the exterior body main body 310, cut along a plane parallel to the XZ plane. FIG. 9 is a cross-sectional view showing the surrounding configuration of the protrusion 230 of the spacer 200a according to the present embodiment. FIG. 9 shows an enlarged view of the protrusion 230 in the negative X-axis direction of the spacer 200a and the surrounding configuration in the configuration shown in FIG. 8. Fig. 10A is a cross-sectional view showing a state before spacer 200a according to the present embodiment is arranged on exterior body main body 310 and intermediate member 400, and Fig. 10B is a cross-sectional view showing a state after spacer 200a according to the present embodiment has been arranged on exterior body main body 310 and intermediate member 400. Figs. 10A and 10B are views corresponding to Fig. 9.

[0059] First, the configuration of the exterior body main body 310 will be described in detail. As shown in Fig. 7 , the exterior body main body 310 includes a bottom 311, a first exterior body wall 312, a second exterior body wall 313, and a pair of third exterior body walls 314. The exterior body main body 310 includes the bottom 311 on the bottom surface facing the negative Z-axis direction, the first exterior body wall 312 on the front surface facing the negative Y-axis direction, the second exterior body wall 313 on the rear surface facing the positive Y-axis direction, and a pair of third exterior body walls 314 on both side surfaces in the X-axis direction. In this embodiment, the exterior body main body 310 is a single member in which the bottom 311, the first exterior body wall 312, the second exterior body wall 313, and the pair of third exterior body walls 314 are integrated. The exterior body main body 310 is integrally molded by aluminum die casting or the like, and is formed as a single member (one component).

[0060] The bottom 311 is a generally rectangular parallelepiped portion elongated in the Y-axis direction and located at the end of the exterior body main body 310 in the negative Z-axis direction. The bottom 311 is disposed in the negative Z-axis direction of the energy storage unit 10 so as to cover the entire surface of the energy storage unit 10 in the negative Z-axis direction, and supports the energy storage unit 10 from the negative Z-axis direction. The bottom 311 is disposed further in the negative Z-axis direction than the energy storage elements 100 and the spacers 200 (200a and 200b) (see FIG. 8 ). The bottom 311 is disposed adjacent to the first exterior body wall 312, the second exterior body wall 313, and a pair of third exterior body wall portions 314. The bottom 311 includes a pair of step portions 311a, a bottom wall 311b, and a second opening 311c.

[0061] The pair of step portions 311a are arranged at both ends of the bottom portion 311 in the X-axis direction and are stepped portions extending in the Y-axis direction. The pair of legs 240 of the spacer 200a are placed on the pair of step portions 311a, and the pair of legs 240 come into contact with the pair of step portions 311a, thereby supporting the spacer 200a.

[0062] The bottom wall 311b is a wall disposed at the end of the bottom 311 in the negative Z-axis direction. The bottom wall 311b is the bottom wall of the exterior body main body 310 (the bottom wall of the exterior body 300). The bottom wall 311b is a flat, rectangular wall portion parallel to the XY plane and elongated in the Y-axis direction, and is disposed with its main surface (the surface with the largest area) facing the Z-axis direction, forming the bottom surface of the exterior body main body 310. The bottom wall 311b is disposed opposite the energy storage unit 10 (the energy storage elements 100 and the spacers 200 (200a and 200b)) in the Z-axis direction (see FIG. 8 ). The bottom wall 311b forms a space S between the energy storage elements 100 and the spacers 200 (200a and 200b). The space S is a space located in the negative Z-axis direction within the internal space of the exterior body main body 310. The space S is a space surrounded by the energy storage device 100, the spacer 200 (200a and 200b), the pair of step portions 311a, the bottom wall 311b, and an intermediate member 400 (described later) (see FIG. 8).

[0063] The second opening 311c is a rectangular through-hole that penetrates the wall of the bottom 311 in the negative Y-axis direction. The second opening 311c is an opening that connects the external space of the exterior body main body 310 with the space S inside the exterior body main body 310. The second opening 311c is an opening that allows a refrigerant to flow into the space S, for example, by being connected to a duct (not shown) that is connected to a blower (not shown) outside the exterior body main body 310. The refrigerant is a fluid such as a gas (air) that cools the energy storage element 100.

[0064] The first exterior body wall 312 and the second exterior body wall 313 are short side walls of the exterior body main body 310 (short side walls of the exterior body 300). The first exterior body wall 312 and the second exterior body wall 313 are arranged with their main surfaces (the surfaces with the largest areas) facing the Y axis direction, and are flat, rectangular wall portions (short side walls) parallel to the XZ plane that form the side surfaces (short side surfaces) of the exterior body main body 310 in the Y axis direction. The first exterior body wall 312 and the second exterior body wall 313 are wall portions that rise in the positive direction of the Z axis from both ends of the bottom 311 in the Y axis direction, and are arranged opposite the energy storage unit 10 in the Y axis direction. The first exterior body wall 312 is adjacent to the bottom 311 and the pair of third exterior body wall portions 314. The second exterior body wall 313 is adjacent to the bottom 311 and the pair of third exterior body wall portions 314.

[0065] The pair of third exterior body walls 314 are long side walls of the exterior body main body 310 (long side walls of the exterior body 300). The pair of third exterior body walls 314 are arranged with their main surfaces (the surfaces with the largest area) facing the X axis direction, and are flat, rectangular wall portions (long side walls) that are parallel to the YZ plane and elongated in the Y axis direction, forming side surfaces (long side surfaces) in the X axis direction of the exterior body main body 310. The pair of third exterior body walls 314 are wall portions that rise in the positive direction of the Z axis from both ends of the bottom 311 in the X axis direction, and are arranged opposite the energy storage unit 10 in the X axis direction. The pair of third exterior body walls 314 are adjacent to the bottom 311, the first exterior body wall portion 312, and the second exterior body wall portion 313.

[0066] With the above configuration, a first opening 310a that opens in the positive direction of the Z axis is formed in the exterior body main body 310. The first opening 310a is formed by the first exterior body wall 312, the second exterior body wall 313, and the pair of third exterior body wall portions 314. The first opening 310a is a rectangular opening that is long in the Y axis direction when viewed from the Z axis direction, and is disposed in a position opposite the bottom 311 of the exterior body main body 310. The first opening 310a is formed to a size that allows the energy storage unit 10 to pass through in the Z axis direction.

[0067] As shown in FIGS. 7 and 8 , the energy storage device 1 further includes an intermediate member 400 inside the exterior body main body 310. The intermediate member 400 is disposed between the spacer 200 (200a and 200b) and the exterior body 300 (the bottom 311 of the exterior body main body 310) in the Z-axis direction and is a member (sealing member) that seals between the spacer 200 and the exterior body 300. Sealing between two members means that when connecting two members, the two members are brought into close contact with each other to fill the gap between the two members. In this embodiment, the intermediate member 400 is a member that fills the gap between the spacer 200 and the exterior body 300 to ensure airtightness so that the refrigerant (air, etc.) flowing through the space S does not leak (pass through).

[0068] In this embodiment, the intermediate member 400 is an elastic body that generates a reaction force when compressed. The intermediate member 400 is formed of rubber such as natural rubber (NR), nitrile rubber (NBR), silicone rubber (Si), styrene butadiene rubber (SBR), chloroprene rubber (CR), butyl rubber (IIR), ethylene propylene rubber (EPDM), urethane rubber (U), or fluororubber; sponge; or an elastic resin. The intermediate member 400 may be formed of any resin material that can be used for the spacer 200, but is preferably formed of a material that is more elastic than the spacer 200 or has a smaller elastic modulus or Young's modulus than the spacer 200. The intermediate member 400 is preferably formed of a material that has a smaller elastic modulus or Young's modulus than the exterior body 300 (exterior body main body 310). The elastic modulus or Young's modulus of the intermediate member 400 can be measured in accordance with JIS K6254:2016 when the intermediate member 400 is made of rubber, sponge, elastic resin, or the like, and in accordance with JIS K7181:2011 when the intermediate member 400 is made of plastic, etc. The larger the elastic modulus or Young's modulus, the more difficult it is to deform, and the smaller the elastic modulus or Young's modulus, the more easily it deforms.

[0069] In the present embodiment, the intermediate member 400 is an insulating member having insulating properties, but the intermediate member 400 may be a conductive member as long as the configuration ensures the insulation of the energy storage device 100 and does not cause any problems. The intermediate member 400 may also have thermal insulation properties. In the present embodiment, the intermediate member 400 is attached (pasted) to the exterior body 300 by adhesion (adhesion) or the like. The intermediate member 400 is a member made of any of the above-mentioned materials, with adhesive or double-sided tape or the like provided on its surface (one side or both sides), and is attached to the exterior body 300. The intermediate member 400 may be attached (pasted) to the spacer 200 by adhesion (adhesion) or the like.

[0070] The intermediate member 400 includes a pair of intermediate members 410 and 420. The intermediate member 410 is an elongated member extending in the Y-axis direction and having a rectangular parallelepiped shape (a rod, a rectangular column, or a column with an elliptical cross section in the XZ plane) that is rectangular when viewed from the Y-axis direction. In the case of a column with an elliptical cross section in the XZ plane, the intermediate member 410 is arranged so that the curved surface of the elliptical shape faces the X-axis direction and the flat surface of the elliptical shape faces the Z-axis direction. The intermediate member 410 extends continuously from one end to the other end of the exterior body main body 310 in the Y-axis direction. The intermediate member 410 is arranged between the spacer 200a and the exterior body 300 in the Z-axis direction (second direction), which intersects with the Y-axis direction (first direction), in which the energy storage device 100 and the spacer 200a are arranged. Specifically, the intermediate member 410 is arranged between the spacer 200a and the bottom 311 of the exterior body 300 (exterior body main body 310). More specifically, the intermediate members 410 are disposed between the portion of the fifth spacer wall portion 225 of the spacer 200a where the protrusions 230 are disposed and the step portion 311a of the bottom portion 311. A pair of intermediate members 410 are disposed at both ends in the X-axis direction of the exterior body main body 310 (bottom portion 311). A pair of intermediate members 410 are disposed aligned in the X-axis direction relative to the pair of step portions 311a and the pair of fifth spacer wall portions 225 (pair of protrusions 230).

[0071] The intermediate member 420 is an elongated member extending in the X-axis direction and having a rectangular parallelepiped shape (a rod, a rectangular column, or a column with an elliptical cross section in the YZ plane) that is rectangular when viewed in the X-axis direction. In the case of a column with an elliptical cross section in the YZ plane, the intermediate member 420 is disposed so that the curved surface of the elliptical shape faces the Y-axis direction and the flat surface of the elliptical shape faces the Z-axis direction. The intermediate member 420 extends continuously from one end to the other end of the exterior body main body 310 in the X-axis direction. The intermediate member 420 is disposed between the spacer 200b and the exterior body 300 in the Z-axis direction. Specifically, the intermediate member 420 is disposed at the end of the exterior body main body 310 (bottom 311) in the positive Y-axis direction, and is disposed between the bottom surface of the spacer 200b in the positive Y-axis direction and the bottom 311 (a pair of step portions 311a and bottom wall 311b) of the exterior body main body 310.

[0072] In this configuration, as shown in FIG. 9 , the protrusion 230 of the spacer 200 a protrudes toward the intermediate member 410 in the Z-axis direction (second direction) and comes into contact with the intermediate member 410. At least one of the surface of the protrusion 230 facing the negative Z-axis direction, the surface of the protrusion 230 facing the positive X-axis direction, and the surface of the protrusion 230 facing the negative X-axis direction comes into contact with the intermediate member 410. In this embodiment, all three surfaces of the protrusion 230 facing the negative Z-axis direction, the surface of the protrusion 230 facing the positive X-axis direction, and the surface of the protrusion 230 facing the negative X-axis direction come into contact with the intermediate member 410. Specifically, at least a portion of the protrusion 230 is embedded in the intermediate member 410. In this embodiment, the entire protrusion 230 is embedded in the intermediate member 410.

[0073] 10A and 10B , as spacer 200a is brought closer to exterior body main body 310 and intermediate member 400, fifth spacer wall portion 225 of spacer 200a compresses intermediate member 410. When leg portion 240 of spacer 200a comes into contact with bottom portion 311 (step portion 311a) of exterior body main body 310, compression of intermediate member 410 by fifth spacer wall portion 225 ends. At this time, protrusion 230 also compresses intermediate member 410 together with fifth spacer wall portion 225, so that protrusion 230 is entirely embedded in intermediate member 410.

[0074] 9 to 10B illustrate and describe the protrusions 230 of the spacer 200a in the negative X-axis direction. However, the same applies to the protrusions 230 of the spacer 200a in the positive X-axis direction. The protrusions 230 in the positive X-axis direction protrude in the Z-axis direction (second direction) toward the intermediate member 410 in the positive X-axis direction and come into contact with the intermediate member 410. Specifically, at least a portion (in this embodiment, the entirety) of the protrusions 230 is embedded in the intermediate member 410. In this manner, at least one of the spacer 200a and the exterior body 300 (the spacer 200a in this embodiment) includes protrusions 230 that protrude in the Z-axis direction (second direction) toward the intermediate member 410 and come into contact with the intermediate member 410. At least one of the spacer 200a and the exterior body 300 (the spacer 200a in this embodiment) includes a plurality of protrusions 230 aligned in the X-axis direction (third direction).

[0075] [2 Description of Effects] As described above, according to the energy storage device 1 of this embodiment, the intermediate member 410 is provided between the spacer 200a and the exterior body 300. As a result, the intermediate member 410 can prevent a gap from being formed between the spacer 200a and the exterior body 300. Furthermore, at least one of the spacer 200a and the exterior body 300 (the spacer 200a in this embodiment) has the protrusion 230 that protrudes toward the intermediate member 410 and comes into contact with the intermediate member 410. As a result, even if there is variation in the distance between the spacer 200a and the exterior body 300, the protrusion 230 can be brought into contact with the intermediate member 410, thereby preventing a gap from being formed between the spacer 200a and the exterior body 300. Therefore, the sealing performance (sealing performance, adhesion) between the spacer 200a and the exterior body 300 can be improved.

[0076] Specifically, in conventional configurations, increasing the thickness of the intermediate member 410 to prevent gaps from forming between the spacer and the exterior body 300 (improving sealing performance) can lead to increased compression of the intermediate member 410, which can increase the repulsive force and make it difficult to assemble the energy storage device. Reducing the thickness of the intermediate member 410 can lead to gaps forming between the spacer and the exterior body 300 (deteriorating sealing performance). Therefore, to mitigate the above problem, it is necessary to individually prepare intermediate members 410 with thicknesses corresponding to the gaps between the spacer and the exterior body 300. This requires additional steps, such as measuring the gap between the spacer and the exterior body 300 in advance, preparing intermediate members 410 with different thicknesses in advance, and determining the combination of the gap between the spacer and the exterior body 300 and the intermediate member 410. Adding these steps reduces the production speed of the energy storage device and is therefore unsuitable for mass production. Therefore, after extensive research, the present inventors have devised an energy storage device that reduces the above problem and is suitable for mass production.

[0077] Specifically, in this embodiment, by contacting the protrusions 230 with the intermediate member 410, even if the thickness of the intermediate member 410 is somewhat small, it is possible to prevent gaps from forming between the spacers 200a and the exterior body 300 (improving sealing). This prevents the intermediate member 410 from being too thick, thereby preventing the intermediate member 410 from being too thick, which would increase the repulsive force (making it difficult to assemble the energy storage device 1). By contacting the protrusions 230 with the intermediate member 410, the amount of compression of the intermediate member 410 can be reduced, thereby preventing the repulsive force from the intermediate member 410 from increasing. Therefore, according to the energy storage device 1, it is possible to prevent gaps from forming between the spacers 200a and the exterior body 300 while preventing the repulsive force from the intermediate member 410 from increasing, thereby improving sealing between the spacers 200a and the exterior body 300. This allows for effective cooling of the energy storage elements 100 and suppressing movement of the spacers 200a within the exterior body 300.

[0078] The energy storage device 1 can prevent gaps from occurring (improve sealing performance) between the spacers 200a (holders) that hold the energy storage elements 100 and the exterior body 300. This allows the energy storage elements 100 to be cooled while the spacers 200a hold them, and prevents the energy storage elements 100 from moving within the exterior body 300.

[0079] At least one of the spacer 200a and the outer casing 300 (in this embodiment, the spacer 200a) is provided with a plurality of protrusions 230, which can further prevent gaps from occurring between the spacer 200a and the outer casing 300 (further improving sealing performance).

[0080] Embedding at least a portion (in this embodiment, the entirety) of protrusion 230 in intermediate member 410 more reliably prevents gaps from occurring between spacer 200a and exterior body 300 (more reliably improves sealing). Contact between intermediate member 410 and at least one of the surface of protrusion 230 facing the negative Z-axis direction, the surface of protrusion 230 facing the positive X-axis direction, and the surface of protrusion 230 facing the negative X-axis direction can more reliably prevent gaps from occurring between spacer 200a and exterior body 300 (more reliably improves sealing).

[0081] By disposing the intermediate member 410 between the spacer 200a and the bottom 311 of the exterior body 300, it is possible to prevent a gap from being formed between the spacer 200a and the bottom 311 of the exterior body 300 (improving sealing performance). This allows the energy storage elements 100 to be effectively cooled when a refrigerant is caused to flow between the spacer 200a and the bottom 311 of the exterior body 300. Specifically, when a refrigerant (air, etc.) flows into the space S from the second opening 311c of the bottom 311, the intermediate member 410 prevents the refrigerant from escaping to both sides of the spacer 200a in the X-axis direction, allowing the refrigerant to flow into the space 212 of the spacer 200a. This allows a larger amount of refrigerant to flow into the space 212 disposed between the spacer 200a and the energy storage elements 100, thereby allowing the energy storage elements 100 to be effectively cooled. By preventing a gap from occurring between the spacer 200a and the bottom 311 of the outer casing 300, the spacer 200a can be stably positioned on the bottom 311 of the outer casing 300, thereby preventing the spacer 200a from moving within the outer casing 300.

[0082] By providing the spacer 200a with the legs 240 that come into contact with the bottom 311 of the exterior body 300, it is possible to further prevent a gap from occurring between the spacer 200a and the bottom 311 of the exterior body 300 (to further improve sealing performance). By having the legs 240 of the spacer 200a come into contact with the bottom 311 of the exterior body 300, it is possible to more stably position the spacer 200a on the bottom 311 of the exterior body 300.

[0083] By extending the protrusions 230 in the Y-axis direction (first direction, the direction in which the energy storage devices 100 and the spacers 200a are arranged), it is possible to prevent gaps from being formed between the spacers 200a and the exterior body 300 in the Y-axis direction (first direction) (improving sealing performance). This makes it possible to effectively cool the energy storage devices 100 when a refrigerant flows in the Y-axis direction (first direction), and to stably position the spacers 200a on the exterior body 300 in the Y-axis direction (first direction).

[0084] Since both ends of the spacer 200a in the X-axis direction (the pair of protrusions 230 and the pair of legs 240, etc.) have the same configuration, the above-mentioned effect can be similarly achieved at both ends of the spacer 200a in the X-axis direction. Since the multiple spacers 200a included in the energy storage device 1 have the same configuration, the above-mentioned effect can be similarly achieved in all of the spacers 200a.

[0085] [3 Description of Modifications] While the energy storage device 1 according to the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment. The embodiment disclosed herein is an example in all respects, and the scope of the present invention includes all modifications within the meaning and scope of the claims.

[0086] (Variation 1) In the above embodiment, spacer 200a is provided with protrusion 230, but exterior body 300 may also be provided with a protrusion. Fig. 11 is a cross-sectional view showing protrusion 311d provided on exterior body 300a according to Variation 1 of this embodiment and the surrounding configuration. Fig. 11 is a view corresponding to Fig. 9.

[0087] As shown in FIG. 9 , the spacer 200c of this modification does not include the protrusion 230 included in the spacer 200a of the above embodiment. The exterior body 300a of this modification includes a protrusion 311d. In this modification, the protrusion 311d is a long, rectangular (rod-shaped) protrusion (convex portion) that is provided on a step portion 311a of the bottom 311 of the exterior body 300a and extends in the Y-axis direction (first direction). The protrusion 311d is a rectangular parallelepiped (rod-shaped) protrusion (convex portion) that is rectangular when viewed from the Y-axis direction. The length of the protrusion 311d in the Y-axis direction is not limited, but the protrusion 311d is preferably formed continuously or intermittently from one end to the other end of the step portion 311a in the Y-axis direction. Specifically, a pair of protrusions 311d aligned in the X-axis direction is provided for a pair of step portions 311a aligned in the X-axis direction. The exterior body 300a includes a plurality of protrusions 311d aligned in the X-axis direction (third direction). Like the protrusion 230 of the spacer 200a in the above embodiment, the protrusion 311d protrudes toward the intermediate member 410 in the Z-axis direction (second direction) and comes into contact with the intermediate member 410. Specifically, at least a portion (in this embodiment, the entire protrusion 311d) is embedded in the intermediate member 410. The other configurations of this modification are the same as those of the above embodiment, and therefore will not be described.

[0088] This modification can also achieve the same effects as the above embodiment. In this modification, the spacer 200c may also have the protrusions 230, similar to the spacer 200a in the above embodiment. In this manner, at least one of the spacer and the exterior body has protrusions that protrude toward the intermediate member 410 in the Z-axis direction (second direction) and come into contact with the intermediate member 410. At least one of the spacer and the exterior body has a plurality of protrusions aligned in the X-axis direction (third direction).

[0089] (Other Modifications) In the above embodiment, the protrusions 230 of the spacer 200a extend in the Y-axis direction, but they may extend in a direction inclined from the Y-axis direction or in the X-axis direction. The protrusions 230 do not have to be elongated (rod-shaped), and the shape and size of the protrusions 230 are not particularly limited.

[0090] In the above embodiment, the spacer 200a includes the protrusion 230. However, in addition to the spacer 200a, or instead of the spacer 200a, the spacer 200b may include the protrusion 230. In this case, the protrusion 230 included in the spacer 200b in the positive Y-axis direction may extend in the X-axis direction. As a result, the protrusion 230 protrudes toward the intermediate member 420 in the Z-axis direction (second direction) and comes into contact with the intermediate member 420. At least a portion of the protrusion 230 is embedded in the intermediate member 420. In this case, similar to the first modification example, the exterior body 300 may include a protrusion that extends in the X-axis direction, protrudes toward the intermediate member 420, and comes into contact with (is embedded in) the intermediate member 420. In particular, when the intermediate member 420 is attached (bonded) to the spacer 200b, it is preferable that the exterior body 300 include a protrusion.

[0091] In the above embodiment, the spacer 200a is provided with a plurality of protrusions 230 aligned in the X-axis direction, but the spacer 200a may be provided with a plurality of protrusions 230 aligned in a direction inclined from the X-axis direction or aligned in the Y-axis direction. The same applies to the leg portions 240.

[0092] In the above embodiment, the spacer 200a includes a pair of protrusions 230 and a pair of legs 240. However, the number of protrusions 230 and the number of legs 240 are not limited. The spacer 200a may include only one protrusion 230, or three or more protrusions 230. Specifically, in the above embodiment, a pair of legs 240 is disposed at the end of the spacer 200a in the positive direction of the X-axis and the end in the negative direction of the X-axis, and one pair of protrusions 230 is disposed on each of the legs 240 at the end in the positive direction of the X-axis and the end in the negative direction of the X-axis. However, this is not limiting, and two protrusions 230 may be disposed on each of the legs 240 at the end in the positive direction of the X-axis and the end in the negative direction of the X-axis. In this case, the two protrusions 230 can extend in the Y-axis direction and be aligned in the X-axis direction. The spacer 200a may include only one leg 240, or three or more legs 240. The spacer 200 a does not necessarily have to include the legs 240 .

[0093] In the above embodiment, at least a portion of the protrusion 230 of the spacer 200a is embedded in the intermediate member 410, but the protrusion 230 may be in contact with the intermediate member 410 without being embedded in the intermediate member 410.

[0094] In the above embodiment, the leg portions 240 of the spacer 200a are in direct contact with the bottom portion 311 of the exterior body 300, but they may be in indirect contact with each other via another member.

[0095] In the above embodiment, the spacer body 210 of the spacer 200b has the plurality of protrusions 211 shown in Fig. 5, but there are no particular limitations on the number, size, or shape of the protrusions 211. The spacer body 210 does not have to have the protrusions 211. This also makes it possible to cool the energy storage elements 100 by flowing a refrigerant through the space between the spacer 200b and the energy storage elements 100.

[0096] In the above embodiment, the spacer wall 220 of the spacer 200a includes the first spacer wall 221, the second spacer wall 222, the third spacer wall 223, the fourth spacer wall 224, and the fifth spacer wall 225. However, the spacer 200a is not limited to including all of these walls. The spacer 200a may be a holder that holds the energy storage elements 100 by including at least one of these walls, or may be a plate-shaped spacer that does not include all of the walls (does not hold the energy storage elements 100). If the spacer 200a does not include the fifth spacer wall 225, the protrusion 230 and the leg 240 may be located on another wall or on the spacer body 210.

[0097] In the above embodiment, all the spacers 200 a have the above configuration, but it is not necessary for any of the spacers 200 a to have the above configuration. In the above embodiment, it is not necessary for the spacers 200 a to have the above configuration on both sides in the X-axis direction.

[0098] In the above embodiment, the spacers 200 (200a and 200b) are arranged alternately with the energy storage elements 100 in the Y-axis direction, but a configuration in which none of the spacers 200 is arranged may be used. Alternatively, a configuration in which only one spacer 200a is arranged may be used.

[0099] In the above embodiment, the intermediate member 400 is an elastic body having a smaller elastic modulus (Young's modulus) than both the spacer 200 and the exterior body 300, but this is not limiting. The intermediate member 400 may be an elastic body having a smaller elastic modulus (Young's modulus) than only one of the spacer 200 and the exterior body 300. The intermediate member 400 may be a member having the same elastic modulus as both the spacer 200 and the exterior body 300, or a member having a larger elastic modulus than both of them.

[0100] In the above embodiment, the intermediate member 410 extends continuously from one end to the other end of the exterior body main body 310 in the Y-axis direction. However, the intermediate member 410 may be divided into multiple members and arranged on the exterior body main body 310. Specifically, in the above embodiment, one intermediate member 410 is arranged at each of the end of the exterior body main body 310 in the positive direction of the X-axis and the end of the exterior body main body 310 in the negative direction of the X-axis. This is not limiting, and two intermediate members 410 may be arranged at each of the end of the exterior body main body 310 in the positive direction of the X-axis and the end of the exterior body main body 310 in the negative direction of the X-axis. In this case, the two intermediate members 410 can extend in the Y-axis direction and be aligned in the X-axis direction. When one protrusion 230 and two intermediate members 410 are arranged on one side in the X-axis direction, the one protrusion 230 can be arranged at a position corresponding to either the inner or outer intermediate member 410 of the two intermediate members 410 in the X-axis direction. When two protrusions 230 and two intermediate members 410 are arranged on one side in the X-axis direction, each protrusion 230 and intermediate member 410 can be arranged in a pair. The same applies to the intermediate member 420.

[0101] In the above embodiment, intermediate member 410 is arranged on bottom 311 of exterior body 300, but it may also be arranged on a wall other than bottom 311 of exterior body 300 (such as a side wall of exterior body main body 310 or a side wall or top wall of lid 320). In this case, protrusion 230 of spacer 200a protrudes toward intermediate member 410 arranged on that wall and comes into contact with (is embedded in) intermediate member 410. Protrusion 230 may protrude in a direction other than the negative Z-axis direction.

[0102] In the above embodiment, the bottom 311 of the exterior body 300 includes the step 311 a, but the step 311 a may not be included. In this case, the leg 240 and the intermediate member 410 of the spacer 200 a may be disposed on the bottom wall 311 b or another portion of the bottom 311.

[0103] In the above embodiment, the height of the exterior body main body 310 in the Z-axis direction is not particularly limited. The exterior body main body 310 may be configured to have a sufficient height in the Z-axis direction to accommodate the power storage unit 10, so that the power storage unit 10 does not protrude from the exterior body main body 310 in the positive direction of the Z-axis. The exterior body main body 310 may have a height of about two-thirds or half of the power storage unit 10 in the Z-axis direction, so that the portion of the power storage unit 10 in the negative direction of the Z-axis is accommodated, and the portion of the power storage unit 10 in the positive direction of the Z-axis is exposed and not accommodated. In this case, the lid 320 may have a height of about one-third or half of the power storage unit 10 in the Z-axis direction, so that the portion of the power storage unit 10 in the positive direction of the Z-axis is accommodated.

[0104] In the above embodiment, a plurality of power storage units 10 aligned in the X-axis direction may be housed inside the exterior body 300. A plurality of power storage units 10 aligned in the Y-axis direction may be housed inside the exterior body 300. When a plurality of power storage units 10 are housed in the exterior body 300, the above-described configuration may be provided for each of the plurality of power storage units 10, or the above-described configuration may not be provided for any of the power storage units 10.

[0105] In the above embodiment, the exterior body 300 includes the exterior body main body 310 and the lid body 320, but the lid body 320 may not be included.

[0106] In the above embodiment, the energy storage unit 10 may include restraining members (end plates, side plates, etc.) that restrain the plurality of energy storage elements 100 and the spacers 200 .

[0107] Any combination of the components of the above-described embodiment and its modifications is also included within the scope of the present invention.

[0108] The present invention can be applied to an electricity storage device or the like that includes an electricity storage element such as a lithium ion secondary battery.

[0109] REFERENCE SIGNS LIST 1 Energy storage device 10 Energy storage unit 100 Energy storage element 110 Container 140 Terminal 200, 200a, 200b, 200c Spacer 210 Spacer body 211 Convex portion 212 Space 220 Spacer wall portion 221 First spacer wall portion 222 Second spacer wall portion 223 Third spacer wall portion 224 Fourth spacer wall portion 225 Fifth spacer wall portion 230, 311d Protrusion 240 Leg portion 300, 300a Exterior body 310 Exterior body body 310a First opening 311 Bottom portion 311a Step portion 311b Bottom wall 311c Second opening 312 First exterior body wall portion 313 Second exterior body wall portion 314 Third exterior body wall portion 320 Lid 400, 410, 420 Intermediate member

Claims

1. An energy storage device comprising: an energy storage element; a spacer; an outer casing; and an intermediate member disposed between the spacer and the outer casing in a second direction that intersects with a first direction in which the energy storage element and the spacer are arranged, wherein at least one of the spacer and the outer casing has a protrusion that protrudes toward the intermediate member in the second direction and comes into contact with the intermediate member.

2. The energy storage device according to claim 1, wherein the spacer holds the energy storage element.

3. The energy storage device according to claim 1 or 2, wherein at least one of the spacer and the exterior body has a plurality of the protrusions arranged in a third direction that intersects with the first direction and the second direction.

4. The electricity storage device according to claim 1 or 2, wherein at least a portion of the protrusion is embedded in the intermediate member.

5. The energy storage device according to claim 1 or 2, wherein the intermediate member is disposed between the spacer and the bottom of the exterior body.

6. The energy storage device according to claim 5, wherein the spacer has legs that contact the bottom of the exterior body.

7. The electricity storage device according to claim 1 or 2, wherein the protrusion extends in the first direction.

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