Power storage device

Abstract

To provide a power storage device capable of suppressing positional deviation of a shim.SOLUTION: An energy storage apparatus includes an energy storage unit including an energy storage device, a shim 300 disposed adjacently to the energy storage unit, and a case which accommodates the energy storage unit and the shim, wherein the case includes a bottom portion on one side in a second direction Z which intersects with a first direction Y along which the energy storage unit and the shim are arranged, the energy storage unit includes a projecting portion 237 which projects toward the shim, and the shim includes a restricting portion 322 which is disposed on the other side in the second direction with respect to the projecting portion and restricts movement of the shim toward one side in the second direction with respect to the energy storage unit.SELECTED DRAWING: Figure 6

Description

[Technical Field]

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

[0002] Patent Document 1 discloses a battery module in which a shim is placed between a battery stack and a housing case, and the shim is used to pressurize the battery stack with a predetermined pressure, thereby making it possible to suppress variations in the pressure even if manufacturing errors occur in the battery stack and the housing case. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-44183 Summary of the Invention [Problem to be solved by the invention]

[0004] In the battery module disclosed in Patent Document 1, if the shim is misaligned when it is placed between the battery stack and the housing case, problems such as the battery stack not being able to be compressed with an appropriate pressure may occur. If the bottom of the housing case has a rounded portion (rounded corner), and the shim is placed in a tilted state in contact with the rounded portion, the shim may cause wear on the housing case or a deterioration in vibration resistance.

[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 misalignment of a shim. [Means for solving the problem]

[0006] An energy storage device according to one aspect of the present invention comprises an energy storage unit having an energy storage element, a shim arranged adjacent to the energy storage unit, and a case that houses the energy storage unit and the shim, wherein the case has a bottom on one side in a second direction that intersects with a first direction in which the energy storage unit and the shim are arranged, the energy storage unit has a convex portion that protrudes toward the shim, and the shim is arranged on the other side of the convex portion in the second direction and has a limiting portion that limits movement of the shim toward the one side in the second direction relative to the energy storage unit. [Effects of the Invention]

[0007] According to the electricity storage device of the present invention, it is possible to suppress misalignment of the shim. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view showing the configuration of an electricity storage device according to an embodiment. [Figure 2] FIG. 2 is an exploded perspective view showing the energy storage elements, spacers, and shims of the energy storage unit included in the energy storage device according to the embodiment. [Figure 3] FIG. 3 is a perspective view showing the configuration of the energy storage element according to the embodiment. [Figure 4] FIG. 4 is a perspective view showing the configuration of a spacer according to the embodiment. [Figure 5] FIG. 5 is a perspective view showing the configuration of a shim according to the embodiment. [Figure 6] FIG. 6 is a perspective view showing a configuration in which the shim according to the embodiment is placed on a spacer. [Figure 7A] FIG. 7A is a cross-sectional view showing the positional relationship between a shim, an electricity storage unit (spacer), and a case (case main body) according to the embodiment. [Figure 7B] FIG. 7B is a perspective view showing the configuration around the shim protrusion of the shim according to the embodiment. [Figure 7C] FIG. 7C is a cross-sectional view showing the configuration around the end of the shim according to the embodiment. [Figure 8] FIG. 8 is a perspective view showing a configuration of a shim according to the first modification of the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] (1) An energy storage device according to one aspect of the present invention comprises an energy storage unit having an energy storage element, a shim arranged adjacent to the energy storage unit, and a case that houses the energy storage unit and the shim, wherein the case has a bottom on one side in a second direction that intersects with a first direction in which the energy storage unit and the shim are arranged, the energy storage unit has a convex portion that protrudes toward the shim, and the shim is arranged on the other side of the convex portion in the second direction and has a limiting portion that limits movement of the shim toward the one side in the second direction relative to the energy storage unit.

[0010] In an energy storage device according to one aspect of the present invention, the case includes a bottom portion on one side in the second direction, and the shim is disposed on the other side in the second direction of the convex portion of the energy storage unit and includes a limiting portion that limits movement of the shim to one side in the second direction relative to the energy storage unit. In this way, in the energy storage device, the limiting portion of the shim limits movement of the shim to one side in the second direction relative to the energy storage unit, thereby positioning the shim relative to the energy storage unit and preventing misalignment of the shim.

[0011] (2) In the energy storage device described in (1) above, the energy storage unit may further include a spacer facing the shim, and the protrusion may be formed on the spacer.

[0012] According to the electricity storage device described in (2) above, by forming a convex portion on the spacer included in the electricity storage unit, it is possible to easily form a convex portion on the electricity storage unit.

[0013] (3) In the energy storage device described in (1) or (2) above, the limiting portion may be a portion of the shim that protrudes in a third direction that intersects with the first direction and the second direction.

[0014] According to the energy storage device described in (3) above, by using the portion of the shim that protrudes in the third direction as the limiting portion, the limiting portion can be easily formed in the shim. Even if the thickness of the shim in the first direction is thin, the size of the limiting portion can be increased by increasing the amount of protrusion of the limiting portion in the third direction.

[0015] (4) In the energy storage device described in any one of (1) to (3) above, the shim may have an opening formed therein into which the protrusion is inserted, and the limiting portion may be a portion of the shim located on the other side of the opening in the second direction.

[0016] According to the electricity storage device described above in (4), the restricting portion can be easily formed in the shim by forming an opening in the shim and configuring a portion of the shim located on the other side of the opening in the second direction as the restricting portion. Even if the thickness of the shim in the first direction is thin, the size of the restricting portion can be increased by increasing the size of the opening.

[0017] (5) In the energy storage device according to any one of (1) to (4) above, the protrusion may be disposed on the other side in the second direction relative to the case.

[0018] According to the electricity storage device described in (5) above, the convex portion of the electricity storage unit is disposed on the other side of the case in the second direction, thereby making it possible to prevent the convex portion from coming into contact with the case.

[0019] 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 its modified examples). 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 only 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.

[0020] In the following description and drawings, the X-axis direction is defined as the short-side direction of the energy storage device, the opposing direction of a pair of long sides of the case for the energy storage device, the arranging direction of a pair of terminals of the energy storage element, or the opposing direction of a pair of short sides of the container for the energy storage element. The Y-axis direction is defined as the long-side direction of the energy storage device, the opposing direction of the pair of short sides of the case for the energy storage device, the arranging direction of the energy storage unit and the shim, the arranging direction of multiple energy storage elements or multiple spacers, the arranging direction of the energy storage element and spacers, the thickness direction of the shim, the thickness direction (flattening direction) of the energy storage element or spacer, or the opposing direction of the pair of long sides of the container for the energy storage element. The Z-axis direction is defined as the arranging direction of the case body and the lid of the case for the energy storage device, the arranging direction of the opening of the case body and the bottom, the arranging direction of the energy storage unit and the shim and the bottom of the case, the protruding direction of the terminals of the energy storage element, the arranging direction of the container body and the container lid for the energy storage element, or the up-and-down direction. The X-axis, Y-axis, and Z-axis directions intersect with each other (orthogonal in this embodiment). Depending on the mode of use, the Z-axis direction may not be the up-down direction, but for the sake of convenience, the following description will be given assuming that the Z-axis direction is the up-down direction.

[0021] 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. The X-axis direction simply refers to both or either of the positive and negative X-axis directions. The terms one side and the other side of the X-axis direction refer to one and the other of the positive and negative X-axis directions. Unless otherwise specified, the center and end portions of a component in the X-axis direction refer to the central and end portions when the component is divided into thirds along the X-axis. 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 orientations, such as "parallel" and "orthogonal," may also refer to cases where the directions are not strictly those directions or orientations. Two directions being parallel (or orthogonal) not only means that the two directions are completely parallel (or orthogonal) but also means that the two directions are substantially parallel (or orthogonal), i.e., there is a difference of, for example, a few percent. In the following explanation, the term "insulation" means "electrical insulation." The volume resistivity of an insulating material is 1×10 6 Ωm or more is preferable, and 1×10 7 Ωm or more is preferable, and 1×10 10 More preferably, it is Ωm or more.

[0022] (Embodiment) [1. Description of the Energy Storage Device 1] First, a schematic configuration of an energy storage device 1 according to the present embodiment will be described. FIG. 1 is a perspective view showing the configuration of the energy storage device 1 according to the present embodiment. FIG. 1 shows the energy storage device 1 in a state where a lid 420 is removed from a case body 410 of a case 400. As a result, FIG. 1 illustrates a portion of the energy storage unit 10 and the shim 300 disposed inside the case 400. FIG. 2 is an exploded perspective view showing the energy storage elements 100 and spacers 200 of the energy storage unit 10 provided in the energy storage device 1 according to the present embodiment, as well as the shim 300. FIG. 2 disassembles the components provided in the energy storage unit 10, illustrating 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, as well as the shim 300.

[0023] The power storage device 1 is a device that can charge with 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 moving 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 rolling stock 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 rolling stock for an electric railway include an electric train, a monorail, a linear motor car, and a hybrid electric 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, etc.

[0024] 1, the energy storage device 1 includes an energy storage unit 10, a shim 300, and a case 400 that houses the energy storage unit 10 and the shim 300. The energy storage device 1 also includes external terminals (a positive external terminal and a negative 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.

[0025] 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 rectangular parallelepiped here refers to a hexahedron with all faces formed of rectangles or squares. The same applies below. 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-constraint type module that does not include any constraint members (end plates, side plates, etc.) that constrain the plurality of energy storage elements 100 and spacers 200 in the Y-axis direction.

[0026] 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, 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 elements, 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 pillar 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 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.

[0027] The spacer 200 is a member that is flat in the Y-axis direction and is arranged alongside the energy storage element 100 in the Y-axis direction, insulating and / or thermally insulating the energy storage element 100 from other components. The spacer 200 is an insulating or thermally insulating plate that is arranged in the positive or negative Y-axis direction of the energy storage element 100, and that insulates and / or thermally insulating the energy storage elements 100 from each other, or from the energy storage element 100 to the shim 300 or the case 400. 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 holding the energy storage element 100 and functioning as a holder that positions the energy storage element 100. The spacer 200 has flow paths through which a refrigerant (a fluid such as air) flows, and thus also functions to cool the energy storage element 100.

[0028] 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 heat-insulating material such as mica.

[0029] Hereinafter, the spacers 200 arranged between 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 200a are arranged opposite the two energy storage elements 100. 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 shim 300 or the case 400) will also be referred to as spacers 200b. The spacers 200b in the negative Y-axis direction are arranged opposite the energy storage elements 100 at the ends in the negative Y-axis direction and the shim 300. The spacers 200b in the positive Y-axis direction are arranged opposite the energy storage elements 100 at the ends in the positive Y-axis direction and the side wall of the case 400. The spacers 200 (spacers 200a, 200b) are arranged alternately with the energy storage elements 100. FIG. 2 shows a configuration in which two energy storage elements 100, two spacers 200a, and one spacer 200b are alternately arranged, but the other spacers 200a and 200b are also alternately arranged with the energy storage elements 100 in a similar manner.

[0030] Specifically, as shown in FIG. 2 , the spacer 200a is an intermediate spacer (intermediate holder, middle holder) that has wall portions 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 that holds the two energy storage elements 100. The spacer 200b is an end spacer (end holder) that has wall portions 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 that holds the one energy storage element 100. In other words, 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 that supports two energy storage elements 100 on both sides in the Y-axis direction, and the spacer 200b has a single-sided support configuration that supports one energy storage element 100 on only one side in the Y-axis direction. The spacer 200a may have a single-sided support structure. All of 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.

[0031] In this embodiment, all of the spacers 200 (spacers 200a, 200b) are connected or fixed to each other so that adjacent spacers 200 are connected or fixed to each other. The energy storage unit 10 is compressed by a constant pressure load by the shim 300 inside the case 400 (case body 410). As a result, the entire energy storage unit 10 is fixed to the case 400 (case body 410).

[0032] The shim 300 is a plate-like, substantially rectangular member disposed adjacent to the energy storage unit 10. The shim 300 is disposed alongside the energy storage unit 10 in the Y-axis direction (first direction). The shim 300 is disposed facing the energy storage unit 10 (the spacer 200b in the negative Y-axis direction) in the negative Y-axis direction of the energy storage unit 10, and is a member (shim) that compresses the energy storage unit 10 at a constant pressure in the Y-axis direction. The shim 300 is formed of a metal member such as iron, stainless steel, plated steel plate, aluminum, or aluminum alloy, but may also be formed of a non-metallic member with high strength (hardness), such as ceramics or high-hardness resin. In this embodiment, the shim 300 is formed of a single shim, but may also be formed of multiple shims. The thickness of one shim in the Y-axis direction is approximately 0.3 mm to 5 mm, preferably approximately 0.5 mm to 3.5 mm. The thickness and number of shims constituting the shim 300 are appropriately changed depending on the amount of compression of the electricity storage unit 10 in the Y-axis direction when the electricity storage unit 10 is compressed at a constant pressure in the Y-axis direction.

[0033] The case 400 is a substantially rectangular parallelepiped (box-shaped) container (module case) that constitutes the exterior body (housing, outer shell) of the energy storage device 1. The case 400 is arranged outside the energy storage unit 10 and the shim 300, fixes the energy storage unit 10 and the like in predetermined positions, and protects them from impacts and the like. The case 400 is a metal case made of a metal member such as aluminum, aluminum alloy, stainless steel, iron, or plated steel sheet. In this embodiment, the case 400 is formed (integrally molded) by die-casting aluminum (aluminum die-casting). The case 400 may be made of an insulating member such as any resin material that can be used for the spacer 200 included in the energy storage unit 10.

[0034] 1, case 400 includes case main body 410 constituting the main body of case 400, and lid body 420 constituting the lid of case 400. Case main body 410 is a housing (casing) with an opening 410a formed in the positive direction of the Z axis, and accommodates power storage unit 10 and shim 300. A bottom portion (bottom wall portion) of case main body 410 located at the end in the negative direction of the Z axis is referred to as bottom portion 411, and a side portion (side wall portion) of case main body 410 located at the end in the negative direction of the Y axis is referred to as side portion 412.

[0035] The bottom 411 is a portion of the case 400 (case main body 410) that is arranged on one side in the Z-axis direction (second direction) that intersects with the Y-axis direction (first direction) that is the arrangement direction of the power storage units 10 and the shim 300. The bottom 411 is a portion of the case 400 (case main body 410) that is arranged on one side in the Z-axis direction (second direction) that intersects with the Y-axis direction (first direction) that is the arrangement direction of the power storage units 10 and the shim 300. The bottom 411 is arranged in the Z-axis direction of the power storage unit 10 so as to cover the entire surface of the power storage unit 10 in the Z-axis direction, and supports the power storage unit 10 from the Z-axis direction. The bottom 411 is arranged adjacent to the side portion 412.

[0036] The side portion 412 is a portion of the case 400 (case main body 410) that is disposed in the negative Y-axis direction (one side in the first direction). The side portion 412 is a short side wall (short side wall of the case 400) of the case main body 410 in the negative Y-axis direction. The side portion 412 is disposed with its main surface (the surface with the largest area) facing the Y-axis direction, and is a flat, rectangular wall portion that is parallel to the XZ plane and forms a side surface (short side surface) of the case main body 410 in the negative Y-axis direction. The side portion 412 is a wall portion that rises in the positive Z-axis direction from the end of the bottom portion 411 in the negative Y-axis direction, and is disposed opposite the shim 300 in the Y-axis direction.

[0037] The lid 420 is a flat, rectangular member that closes the opening 410a of the case body 410. The opening 410a is a rectangular opening that is elongated in the Y-axis direction when viewed from the Z-axis direction and is disposed at a position opposite the bottom 411 of the case body 410. The opening 410a is large enough to allow the power storage unit 10 and the shim 300 to pass through in the Z-axis direction. After the power storage unit 10 and the shim 300 are inserted through the opening 410a of the case body 410, the case body 410 and the lid 420 are joined together by screwing with bolts or the like, welding, adhesive bonding, or the like. This results in the case 400 having a structure in which the interior is sealed (hermetically sealed). A terminal block for external terminals (positive external terminal and negative external terminal) may be attached to the case body 410, the lid 420, the spacer 200 (200b), or the like, and the external terminals may be disposed on the terminal block.

[0038] Next, the configurations of the energy storage devices 100, the spacers 200 (particularly the spacers 200b), and the shims 300 will be described in detail.

[0039] [1.1 Description of the energy storage element 100] Fig. 3 is a perspective view showing the configuration of an 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 device 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 the current collectors and the container 110, but these are not shown in the figure (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 device 100, and various types can be selected. The gasket may be made of any insulating material. In addition to the above-mentioned components, the energy storage device 100 may also include spacers disposed on the sides of the electrode assembly, insulating films encasing the electrode assembly, and insulating films (such as shrink tubes) 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 when the pressure inside the container 110 increases excessively, a liquid injection part (not shown) for injecting electrolyte into the container 110, and the like. 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 wall portions of the spacers 200 and the case 400 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 disposed opposite the wall portion of the spacer 200 and the bottom portion 411 of the case 400 in the Z-axis direction. The bottom surface 113 is disposed 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 and are arranged on the container lid 130. The terminals 140 are arranged protruding 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 assembly via current collectors. The terminals 140 are metal members that conduct electricity stored in the electrode assembly 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 assembly. The terminals 140 are made of 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. As the active material used in the positive electrode active material layer and the negative electrode active material layer, any known material capable of absorbing and releasing charge-transporting ions can be used. 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 in which electrode plates are folded in an accordion-like shape.

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

[0046] 1.2 Description of spacer 200b Next, the configuration of spacer 200b of spacer 200 will be described in detail. FIG. 4 is a perspective view showing the configuration of spacer 200 (spacer 200b) according to this embodiment. FIG. 4 shows an enlarged view of spacer 200b located at the end of energy storage unit 10 in the negative Y-axis direction shown in FIG. 2, and a further enlarged view of protruding portion wall portion 236 (convex portion 237) of spacer protrusion 231. Spacer 200b located at the end of energy storage unit 10 in the positive Y-axis direction may not include protruding portion wall portion 236 (convex portion 237), but otherwise has the same configuration as spacer 200b located at the end of energy storage unit 10 in the negative Y-axis direction. Therefore, hereinafter, spacer 200b located at the end of energy storage unit 10 in the negative Y-axis direction will be illustrated, and the configuration of spacer 200b will be described in detail.

[0047] 4, the spacer 200b has a shape in which the positive half of the spacer 200b in the X-axis direction and the negative half of the spacer 200b in the X-axis direction have the same shape. In other words, the spacer 200b 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 200b includes a spacer main body 210, a spacer wall 220, a spacer protrusion 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 200b and is disposed parallel to the XZ plane. The spacer main body 210 is disposed in the negative Y-axis direction of the energy storage element 100 that is located at the end of the energy storage unit 10 in the negative Y-axis direction. The spacer main body 210 is disposed opposite the long side surface 111 in the Y-axis direction of the container 110 of the energy storage element 100, covering the entire surface of the long side surface 111 that faces the spacer main body 210, and in contact with the long side surface 111. The surface of the spacer main body 210 in the positive Y-axis direction is provided with a plurality of protrusions (not shown) that form flow paths for a refrigerant (gas such as air or liquid, etc.) that flows between the spacer main body 210 and the energy storage element 100.

[0049] The spacer wall portions 220 are walls arranged on both sides in the Z-axis direction and both sides in the X-axis direction of the energy storage element 100. The spacer wall portions 220 include spacer wall portions 221 arranged on both sides in the Z-axis direction at both ends in the X-axis direction of the energy storage element 100, and spacer wall portions 222 arranged on both sides in the X-axis direction at both ends in the Z-axis direction of the energy storage element 100. The spacer wall portions 221 are flat plate-shaped portions parallel to the XY plane protruding in the positive direction of the Y-axis from both Z-axis direction end edges at both ends in the X-axis direction of the spacer main body portion 210, and are arranged opposite the container lid portion 130 and the bottom surface 113 of the container 110 of the energy storage element 100 in the Z-axis direction. The spacer wall portions 222 are flat plate-shaped portions parallel to the YZ plane protruding in the positive direction of the Y-axis from both X-axis direction end edges at both ends in the Z-axis direction of the spacer main body portion 210, and are arranged opposite a pair of short side surfaces 112 of the container 110 of the energy storage element 100 in the X-axis direction. In this way, the spacer walls 220 (221 and 222) are arranged to cover the four corners located at both ends in the Z-axis direction and both ends in the X-axis direction of the energy storage device 100. In this way, the spacer 200b holds the energy storage device 100.

[0050] The spacer protrusion 230 is a protrusion that protrudes from the spacer main body 210 in the negative direction of the Y axis. The spacer protrusion 230 protrudes toward the shim 300. The spacer protrusion 230 is disposed facing the shim 300 in the Y axis direction and in contact with the shim 300. The spacer protrusion 230 is a portion of the energy storage unit 10 that receives a constant pressure load from the shim 300. In this embodiment, five spacer protrusions 230 that protrude from the spacer main body 210 in the negative direction of the Y axis are arranged side by side at intervals in the X axis direction. The five spacer protrusions 230 are also referred to as spacer protrusion 231, spacer protrusion 232, spacer protrusion 233, spacer protrusion 234, and spacer protrusion 235, in that order, from the spacer protrusion 230 at the end in the positive direction of the X axis to the spacer protrusion 230 at the end in the negative direction of the X axis.

[0051] The spacer protrusions 230 (231 to 235) are protrusions that protrude in the negative Y-axis direction from the surface of the spacer main body 210 facing the negative Y-axis direction and are long in the Z-axis direction. When manufacturing the energy storage device 1, a manufacturing device for the energy storage device 1 is inserted into the gaps between the spacer protrusions 230 (231 to 235) to hold the energy storage unit 10 and insert the energy storage unit 10 into the case 400 (case main body 410) in a state where the energy storage unit 10 is compressed in the Y-axis direction. The spacer protrusions 230 (231 to 235) have multiple recesses, each recessed in the surface facing the negative Y-axis direction, arranged side by side in the Z-axis direction (and the X-axis direction), but the arrangement position and number of the recesses are not limited.

[0052] The spacer protrusion 231 includes a protrusion wall 236 at its end in the positive direction of the Z axis. The protrusion wall 236 is a flat plate-shaped wall that protrudes in the positive direction of the Z axis from the surface of the spacer protrusion 231 in the positive direction of the Z axis and extends in the Y axis direction from one end to the other end of the spacer protrusion 231 in the Y axis direction, and is parallel to the YZ plane. The protrusion wall 236 includes a convex portion 237 at its end in the negative direction of the Y axis. The convex portion 237 is a protrusion (projection) that protrudes in the negative direction of the Y axis from the surface of the spacer protrusion 231 in the negative direction of the Y axis. Similarly, the spacer protrusion 235 includes a protrusion wall 236 (convex portion 237) at its end in the positive direction of the Z axis. The protrusion wall 236 (convex portion 237) of the spacer protrusion 235 has the same configuration as the protrusion wall 236 (convex portion 237) of the spacer protrusion 231, and therefore description thereof will be omitted. In this way, the spacer 200b has two protruding wall portions 236 (convex portions 237) at both ends in the X-axis direction.

[0053] The pair of legs 240 are protrusions (convex portions) that protrude in the negative Z-axis direction from both ends in the X-axis direction at the negative Z-axis direction ends of the spacer main body 210 and extend in the Y-axis direction. The pair of legs 240 are legs of the spacer 200b, and are placed on the bottom 411 of the case 400 to support the spacer 200b relative to the case 400. The number, shape, size, etc. of the legs 240 are not particularly limited as long as they are configured to support the spacer 200b.

[0054] [1.3 Explanation of Sim 300] Next, the configuration of the shim 300 and the positional relationship between the shim 300, the energy storage unit 10 (spacer 200b), and the case 400 (case main body 410) will be described in detail. FIG. 5 is a perspective view showing the configuration of the shim 300 according to this embodiment. FIG. 5 shows an enlarged view of the shim 300 shown in FIG. 2. FIG. 6 is a perspective view showing the configuration of the shim 300 according to this embodiment when placed on the spacer 200b. FIG. 6 shows a view of the shim 300 shown in FIG. 5 attached to the spacer 200b shown in FIG. 4, and an enlarged view of the configuration around the shim protrusion 320 of the shim 300. FIG. 7A is a cross-sectional view showing the positional relationship between the shim 300 according to this embodiment, the energy storage unit 10 (spacer 200b), and the case 400 (case main body 410). 7A shows a cross section of the configuration in which the energy storage unit 10 and the shim 300 are arranged in the case main body 410 shown in FIG. 1 , taken along a plane that includes the VIIA-VIIA line located in the positive direction of the X-axis of the spacer protrusion 231 and is parallel to the YZ plane. FIG. 7B is a perspective view showing the configuration around the shim protrusion 320 of the shim 300 according to this embodiment. FIG. 7B shows an enlarged view of the configuration around the shim protrusion 320 of the shim 300 shown in FIG. 7A, viewed obliquely from above. FIG. 7C is a cross section showing the configuration around the shim end portion 330 of the shim 300 according to this embodiment. FIG. 7C shows an enlarged view of the configuration around the shim end portion 330 of the shim 300 shown in FIG. 7A.

[0055] As shown in FIG. 5, the shim 300 includes a shim main body 310, a shim protruding portion 320, and a shim end portion 330.

[0056] [1.3.1 Description of the shim body 310] The shim main body 310 is a flat, rectangular portion constituting the main body of the shim 300 and is disposed parallel to the XZ plane. The shim main body 310 is a flat portion oriented in the Y-axis direction with a constant thickness in the Y-axis direction. As shown in FIG. 7A , the shim main body 310 is disposed in the negative Y-axis direction of the energy storage unit 10 and is in contact with the energy storage unit 10. Specifically, the shim main body 310 is disposed in the negative Y-axis direction of the spacer protrusion 230 of the spacer 200b included in the energy storage unit 10 so as to cover almost the entire surface of the spacer protrusion 230 when viewed from the Y-axis direction. The shim main body 310 is disposed opposite the spacer protrusion 230 in the Y-axis direction and in contact with the spacer protrusion 230. The shim main body 310 is disposed in the positive Y-axis direction of the side portion 412 of the case body 410 and is disposed opposite the side portion 412 in the Y-axis direction and in contact with the side portion 412. As a result, the shim main body 310 is disposed between the spacer protruding portion 230 of the spacer 200b and the side portion 412 of the case main body 410, in a state where it is sandwiched between the spacer protruding portion 230 and the side portion 412.

[0057] [1.3.2 Explanation of shim protrusion 320] The shim protrusion 320 is a protrusion that protrudes from the shim main body 310 in the positive direction of the Z axis (the other side in the second direction). The shim protrusion 320 is a plate-like portion that is generally inverted L-shaped when viewed in the Y axis direction. Two shim protrusions 320 are arranged to protrude in the positive direction of the Z axis from both ends of the shim main body 310 in the X axis direction. In other words, the shim 300 includes two shim protrusions 320 that are aligned in the X axis direction (a third direction intersecting the first and second directions). Each of the two shim protrusions 320 includes an intermediate portion 321 and a limiting portion 322. The thickness of the shim protrusions 320 (the intermediate portion 321 and the limiting portion 322) in the Y axis direction is not particularly limited, but in this embodiment, the thickness of each shim protrusion 320 (the intermediate portion 321 and the limiting portion 322) in the Y axis direction is the same as the thickness of the shim main body 310 in the Y axis direction.

[0058] The two shim protrusions 320 have shapes that are symmetrical with respect to a plane that passes through the center position of the shim 300 and is parallel to the YZ plane. Therefore, the two shim protrusions 320 have opposite orientations in the X-axis direction. When describing the outward direction in the X-axis direction, the shim protrusion 320 in the positive X-axis direction is referred to as the "positive X-axis direction," while the shim protrusion 320 in the negative X-axis direction is referred to as the "negative X-axis direction." When describing the inward direction in the X-axis direction, the shim protrusion 320 in the positive X-axis direction is referred to as the "negative X-axis direction," while the shim protrusion 320 in the negative X-axis direction is referred to as the "positive X-axis direction." The following describes the shim protrusion 320 in the positive X-axis direction of the two shim protrusions 320. The description of the shim protrusion 320 in the negative X-axis direction is omitted because it can be interpreted by reversing its orientation in the X-axis direction.

[0059] The intermediate portion 321 is a flat plate-like portion parallel to the XZ plane that protrudes in the positive Z direction from the edge of the shim main body 310 in the positive Z direction at the end of the X direction. The surface of the intermediate portion 321 on the outer side in the X direction (positive X direction) extends parallel to the Z direction, and the surface on the inner side in the X direction (negative X direction) inclines outward in the X direction (positive X direction) as it approaches the positive Z direction. As a result, the width of the intermediate portion 321 in the X direction decreases as it approaches the positive Z direction. The end of the intermediate portion 321 in the positive Z direction is connected to the limiting portion 322. In other words, the intermediate portion 321 is a portion that connects the shim main body 310 and the limiting portion 322.

[0060] The limiting portion 322 is a flat portion parallel to the XZ plane that protrudes from the intermediate portion 321 outward in the X-axis direction (positive X-axis direction). The surface of the limiting portion 322 facing the negative Z-axis direction extends parallel to the X-axis direction, and the surface facing the positive Z-axis direction inclines in the negative Z-axis direction as it moves outward in the X-axis direction (positive X-axis direction). As a result, the width of the limiting portion 322 in the Z-axis direction decreases as it moves outward in the X-axis direction (positive X-axis direction). In this way, the limiting portion 322 is a portion of the shim 300 that protrudes in the X-axis direction (third direction intersecting the first and second directions).

[0061] The intermediate portion 321 protrudes from the shim main body 310 in the positive direction of the Z axis, and the limiting portion 322 protrudes from the intermediate portion 321 outward in the X axis direction (positive direction of the X axis), thereby forming an opening 323 on the outer side of the intermediate portion 321 in the X axis direction (positive direction of the X axis). The opening 323 is a recess (notch) formed by recessing the surface of the shim protruding portion 320 on the outer side in the X axis direction (positive direction of the X axis) inward in the X axis direction (negative direction of the X axis), and penetrates in the Y axis direction. As shown in FIG. 6 , a protrusion 237 of the protrusion wall portion 236 of the spacer 200b is inserted into the opening 323. That is, the energy storage unit 10 (spacer 200b) has a protrusion 237 that protrudes toward the shim 300, and the protrusion 237 is inserted into the opening 323. The protrusion 237 penetrates the opening 323 in the Y axis direction and protrudes from the shim protruding portion 320 in the negative direction of the Y axis.

[0062] The limiting portion 322 is a portion of the shim 300 located in the positive Z-axis direction (the other side in the second direction) of the opening 323. Therefore, the limiting portion 322 is located in the positive Z-axis direction (the other side in the second direction) of the protruding portion 237. The limiting portion 322 is located in contact with the protruding portion 237 in the positive Z-axis direction of the protruding portion 237 and is supported by the protruding portion 237. This limits movement of the limiting portion 322 in the negative Z-axis direction relative to the spacer 200b. The limiting portion 322 limits movement of the shim 300 in the negative Z-axis direction (one side in the second direction) relative to the energy storage unit 10 (spacer 200b). The intermediate portion 321 is a portion of the shim 300 located inward in the X-axis direction (the negative X-axis direction) of the opening 323. Therefore, the intermediate portion 321 is located inward in the X-axis direction (the negative X-axis direction) of the protruding portion 237. In the present embodiment, the intermediate portion 321 is disposed apart from the protruding portion 237, but may be disposed in contact with the protruding portion 237. This limits the movement of the intermediate portion 321 outward in the X-axis direction (positive direction of the X-axis) relative to the spacer 200b. The intermediate portion 321 limits the movement of the shim 300 outward in the X-axis direction (positive direction of the X-axis) relative to the energy storage unit 10 (spacer 200b).

[0063] In this way, the shim protrusion 320 functions as a portion that limits (positions) the movement of the shim 300 relative to the energy storage unit 10 (spacer 200b). Two shim protrusions 320 are arranged at both ends of the shim 300 in the X-axis direction, and the convex portion 237 of the protrusion wall 236 of the spacer protrusion 231 of the spacer 200b is arranged on the shim protrusion 320 facing the positive X-axis direction. The convex portion 237 of the protrusion wall 236 of the spacer protrusion 235 of the spacer 200b is arranged on the shim protrusion 320 facing the negative X-axis direction. Therefore, the two limiting portions 322 of the two shim protrusions 320 stably position the shim 300 in the Z-axis direction. The two intermediate portions 321 of the two shim protrusions 320 limit the movement of the shim 300 to both sides in the X-axis direction. Shim protrusion 320 can also be used as a portion to be grasped by manufacturing equipment for power storage device 1 when shim 300 is transported during the manufacture of power storage device 1.

[0064] As shown in FIGS. 7A and 7B , the shim protrusion 320 is disposed so as to protrude in the positive direction of the Z axis from the side portion 412 of the case main body 410 of the case 400. Specifically, the middle portion 321 is disposed so as to protrude in the positive direction of the Z axis from the side portion 412. Similarly, the protrusion wall portion 236 of the spacer 200b is disposed so as to protrude in the positive direction of the Z axis from the side portion 412. The protrusion 237 protrudes in the negative direction of the Y axis until it reaches a position on the side portion 412 in the positive direction of the Z axis, and the end of the protrusion 237 in the negative direction of the Y axis is disposed in the positive direction of the Z axis from the side portion 412. In this way, the protrusion 237 is disposed in the positive direction of the Z axis (the other side in the second direction) from the case 400 (case main body 410). The lid 420 is disposed in the positive direction of the Z axis from the case main body 410, but the lid 420 is formed in a shape that does not contact the protrusion 237.

[0065] 1.3.3 Shim End 330 The shim end 330 is a portion of the shim main body 310 that is located in the negative Z-axis direction (one side in the second direction). The shim end 330 is a portion of the shim 300 that extends in the X-axis direction and is located at the end of the shim 300 in the negative Z-axis direction. As shown in FIGS. 7A and 7C , the shim end 330 does not contact the energy storage unit 10. That is, the portion of the end of the shim 300 in the negative Z-axis direction that does not contact the energy storage unit 10 is referred to as the shim end 330. Specifically, the shim end 330 is located at a position that does not face the spacer protrusion 230 in the Y-axis direction, and is therefore not in contact with the spacer protrusion 230. The shim end 330 is located so as to protrude from the spacer protrusion 230 in the negative Z-axis direction. The shim end 330 is located in the positive Y-axis direction of the side 412 of the case main body 410, faces the side 412 in the Y-axis direction, and is in contact with the side 412. The shim end 330 is disposed apart from the bottom 411 of the case body 410. This will be described in detail below.

[0066] As shown in FIGS. 7A and 7C , the bottom 411 includes a bottom wall 411a and a step portion 411b, and the step portion 411b includes a case end portion 411c. The bottom wall 411a is the bottom wall of the case main body 410 (case 400) and is disposed at the end of the bottom 411 in the negative Z-axis direction. The bottom wall 411a is a flat, rectangular wall portion that is 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. The bottom wall 411a is disposed opposite the energy storage unit 10 in the Z-axis direction. The step portion 411b is disposed at the end of the bottom 411 in the negative Y-axis direction and is a stepped (step-like) portion that extends in the X-axis direction. The step portion 411b protrudes from the side portion 412 in the positive Y-axis direction and is disposed in the negative Z-axis direction of the shim 300. The bottom 411 may have a space that serves as a flow path for a refrigerant (gas such as air or liquid, etc.) that cools the storage element 100, and an opening (through hole) that connects the space to the outside of the case 400.

[0067] In this configuration, the step portion 411b is disposed at a distance from the shim end portion 330 of the shim 300. That is, the case end portion 411c located at the end portion of the step portion 411b in the positive Z-axis direction is disposed at a distance from the shim end portion 330. The case end portion 411c is a connecting portion of the bottom portion 411 with the side portion 412. The case end portion 411c is a corner portion of the inner surface of the bottom portion 411 of the case 400 (case main body 410). The case end portion 411c is an end portion (an end portion in the negative Z-axis direction) of the case 400 (case main body 410) on one side in the Z-axis direction (a second direction) that intersects with the Y-axis direction (a first direction) in which the power storage unit 10 and the shim 300 are arranged. The surface of the case end portion 411c in the positive Z-axis direction has an inclined surface that inclines in the positive Z-axis direction as it approaches the negative Y-axis direction (a curved surface that curves in the positive Z-axis direction). That is, a rounded portion (corner radius) is formed on case end portion 411c, which is the connecting portion of bottom portion 411 with side portion 412.

[0068] In this way, the shim end 330 faces the case end 411c in the Z-axis direction (second direction) and is disposed at a distance from the case end 411c. In other words, the shim 300 is disposed at a distance from the bottom 411 of the case 400. This prevents the shim 300 (shim end 330) from coming into contact with the rounded portion of the bottom 411 (case end 411c).

[0069] [2. Description of Manufacturing Method of Energy Storage Device 1] The energy storage device 1 configured as described above is manufactured by a manufacturing apparatus (not shown) for the energy storage device 1 as follows. First, the manufacturing apparatus stacks a plurality of energy storage elements 100 and a plurality of spacers 200 (200a and 200b) to form an energy storage unit 10. The manufacturing apparatus inserts a jig between the plurality of spacer protrusions 230 provided on the spacer 200b to sandwich and hold the energy storage unit 10 from both sides in the Y-axis direction, and compresses the energy storage unit 10 in the Y-axis direction. In the energy storage element 100, the container 110 may bulge in the Y-axis direction depending on the electrode assembly housed therein and the amount and composition of the electrolyte. The spacer 200 may have a material and shape that allows elastic deformation. The manufacturing apparatus compresses the bulging amounts of the plurality of energy storage elements 100 provided in the energy storage unit 10 and the elastically deformable amount of the spacer 200.

[0070] At this time, the manufacturing device transports the shim 300 by, for example, air-sucking the shim 300 or gripping the shim protrusion 320, and positions the limiting portion 322 of the shim 300 in the positive direction of the Z axis of the protrusion 237 of the spacer 200b. As a result, the shim 300 is supported (held) by the energy storage unit 10 (spacer 200b), and movement of the shim 300 in the negative direction of the Z axis relative to the energy storage unit 10 is limited.

[0071] Next, the manufacturing equipment inserts the energy storage unit 10 and the shim 300 into the case body 410 while compressing the energy storage unit 10 in the Y-axis direction. As a result, the energy storage unit 10 and the shim 300 are disposed in the case body 410 with the shim 300 spaced apart from the side portion 412 of the case body 410. Next, the manufacturing equipment releases the compression of the energy storage unit 10. As a result, the bulging portions of the compressed energy storage elements 100 and the elastically deformable portion of the spacer 200 return to their original state, the energy storage unit 10 expands in the Y-axis direction, and the shim 300 comes into contact with the side portion 412 of the case body 410. Because the shim 300 is positioned and held by the spacer 200b, the shim end 330 is spaced apart from the case end 411c. Thereafter, the manufacturing equipment is removed, resulting in the state shown in FIG. 7A.

[0072] Before or after the energy storage unit 10 is inserted into the case body 410, bus bars, bus bar frames, and the like are arranged for the plurality of energy storage elements 100. Then, the case body 410 and the lid 420 are joined together to house the energy storage unit 10 in the case 400, and the energy storage device 1 is manufactured.

[0073] [3 Explanation of effects] As described above, in the energy storage device 1 according to the present embodiment, the case 400 has the bottom 411 in the negative Z-axis direction (one side in the second direction). The shim 300 is disposed in the positive Z-axis direction (the other side in the second direction) of the protrusion 237 of the energy storage unit 10, and has the limiting portion 322 that limits movement of the shim 300 in the negative Z-axis direction (one side in the second direction) relative to the energy storage unit 10. In this way, in the energy storage device 1, the limiting portion 322 of the shim 300 limits movement of the shim 300 in the negative Z-axis direction (one side in the second direction) relative to the energy storage unit 10, thereby enabling the shim 300 to be positioned relative to the energy storage unit 10, and thus misalignment of the shim 300 can be suppressed.

[0074] The limiting portion 322 of the shim 300 can limit the movement of the shim 300 in the negative Z-axis direction (towards the bottom 411 of the case 400), so that the shim 300 can be prevented from moving (falling) in the negative Z-axis direction with a simple configuration. This can prevent the shim 300 from coming into contact with a rounded portion (corner radius) even if the bottom 411 of the case 400 has such a rounded portion. This can prevent the shim 300 from being disposed in an inclined state, thereby preventing problems such as scraping of the case 400 or deterioration of vibration resistance caused by the shim 300.

[0075] The shim 300 receives the load from the electricity storage unit 10 at a location different from the limiting portion 322 that performs positioning. By separating the portion of the shim 300 that receives the load from the portion that performs positioning, it is possible to suppress the positioning of the shim 300 from affecting the load (constant pressure load) that the shim 300 receives.

[0076] By forming the convex portion 237 on the spacer 200b included in the electricity storage unit 10, the convex portion 237 can be easily formed on the electricity storage unit 10.

[0077] By making the portion of shim 300 that protrudes in the X-axis direction (third direction) into limiting portion 322, limiting portion 322 can be easily formed on shim 300. Even if the thickness of shim 300 in the Y-axis direction (first direction) is thin, the size of limiting portion 322 can be increased by increasing the amount of protrusion of limiting portion 322 in the X-axis direction. While intermediate portion 321 limits movement of shim protruding portion 320 to one side in the X-axis direction, clearance can be maintained on the other side of shim protruding portion 320 in the X-axis direction.

[0078] By forming an opening 323 in the shim 300 and designating a portion of the shim 300 located in the positive direction of the Z axis (the other side in the second direction) of the opening 323 as the limiting portion 322, the limiting portion 322 can be easily formed in the shim 300. Even if the thickness of the shim 300 in the Y axis direction (first direction) is thin, the size of the limiting portion 322 can be increased by increasing the size of the opening 323.

[0079] By arranging the protrusion 237 of the energy storage unit 10 in the positive Z-axis direction (the other side in the second direction) relative to the case 400 (case main body 410), it is possible to prevent the protrusion 237 from coming into contact with the case 400 (case main body 410).

[0080] [4 Explanation of Variations] Although 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.

[0081] (Variation 1) In the above embodiment, the limiting portion 322 of the shim 300 protrudes outward in the X-axis direction, but the configuration of the limiting portion 322 is not limited thereto. The limiting portion 322 may protrude inward in the X-axis direction, or may protrude on both sides in the X-axis direction. The limiting portion 322 may not protrude in the X-axis direction. An example of the configuration of the limiting portion 322 will be described below. FIG. 8 is a perspective view showing the configuration of a shim 301 according to a first modification of this embodiment. FIG. 8 is a view corresponding to FIG. 5.

[0082] 8, shim 301 in this modification has two shim protrusions 320a at both ends in the X-axis direction, instead of the two shim protrusions 320 at both ends in the X-axis direction of shim 300 in the above embodiment. Each of the two shim protrusions 320a has an opening 324, a pair of intermediate portions 325, and a limiting portion 326. In other words, by forming opening 324 in the center of shim protrusion 320a, a pair of intermediate portions 325 are disposed on both sides of opening 324 in the X-axis direction, and limiting portion 326 is disposed in the positive Z-axis direction of opening 324. Opening 324 is a through-hole that penetrates shim protrusion 320a in the Y-axis direction and is circular when viewed from the Y-axis direction.

[0083] The protrusion 237 of the protrusion wall 236 of the spacer 200b is inserted into the opening 324. Therefore, the limiting portion 326 is disposed in the positive Z-axis direction of the protrusion 237 (the other side in the second direction). The limiting portion 326 is disposed in contact with the protrusion 237 in the positive Z-axis direction of the protrusion 237 and is supported by the protrusion 237. As a result, the limiting portion 326 limits movement of the shim 301 in the negative Z-axis direction (one side in the second direction) relative to the energy storage unit 10 (spacer 200b). The pair of intermediate portions 325 are disposed on both sides of the protrusion 237 in the X-axis direction. The intermediate portions 325 may be disposed spaced apart from the protrusion 237 or may be disposed in contact with the protrusion 237. As a result, the intermediate portions 325 limit movement of the shim 301 in both sides in the X-axis direction relative to the energy storage unit 10 (spacer 200b). The other configurations of this modified example are the same as those of the above embodiment, and therefore description thereof will be omitted.

[0084] This modification can also achieve the same effects as the above-described embodiment. In this modification, a through hole (opening 324) is formed in the shim 301, and a portion located in the positive direction of the Z axis (the other side in the second direction) of the through hole (opening 324) is set as the limiting portion 326, thereby easily forming the limiting portion 326 in the shim 301. Even if the thickness of the shim 301 in the Y axis direction (first direction) is thin, the size of the limiting portion 326 can be increased by increasing the size of the through hole (opening 324). The pair of intermediate portions 325 can limit movement of the shim 301 in both directions in the X axis direction relative to the energy storage unit 10 (spacer 200b).

[0085] In this modification, the shape of opening 324 as viewed in the Y-axis direction is not limited to a circle, but may be an ellipse, an oval, a rectangle, or another polygonal shape. The size of opening 324 is also not particularly limited. Opening 324 may be located at the end of shim protrusion 320a.

[0086] (Other variations) In the above embodiment, the protrusion wall portions 236 of both the spacer protrusions 231 and 235 of the spacer 200b are provided with the convex portions 237, but this is not limiting. Only one of the spacer protrusions 231 and 235 may be provided with the convex portion 237. A portion of the spacer protrusions 231 and 235 other than the protrusion wall portion 236 may be provided with the convex portion 237. Any of the spacer protrusions 232 to 234 may be provided with the convex portion 237. A portion of the spacer 200b other than the spacer protrusion 230 may be provided with the convex portion 237. A member of the energy storage unit 10 (such as the energy storage element 100) other than the spacer 200b may be provided with the convex portion 237. The limiting portion 322 and the like of the shim 300 are arranged at positions corresponding to the positions of the convex portions 237.

[0087] In the above embodiment, the protrusion 237 is arranged in the positive direction of the Z axis relative to the case body 410, but depending on the shape of the case body 410, it may not be arranged in the positive direction of the Z axis relative to the case body 410.

[0088] In the above embodiment, the limiting portion 322 is a portion in the positive Z-axis direction of the opening 323 formed in the shim 300, but this is not limited to this. The limiting portion 322 may be a portion that protrudes in the X-axis direction from the edge of the shim main body 310 in the X-axis direction, or the limiting portion 322 may be disposed without forming an opening 323 in the shim 300.

[0089] In the above embodiment, the shim 300 is described as having two shim protrusions 320, but the number of shim protrusions 320 is not particularly limited, and the shim 300 may have only one shim protrusion 320. The shim 300 may have three or more shim protrusions 320. In this case, the shim protrusion 320 and its surrounding structure added to the above structure may have the same structure as the above, or may have a different structure from the above.

[0090] In the above embodiment, the shim 300 is arranged at a distance from the bottom 411 of the case 400, but as long as the shim 300 can be positioned relative to the energy storage unit 10, the shim 300 may be arranged in contact with the bottom 411.

[0091] In the above embodiment, the spacer wall 220 of the spacer 200b has a plurality of walls, but this is not limiting. The spacer 200b may be a holder that holds the energy storage elements 100 by including at least one of the walls included in the spacer wall 220, or may be a spacer that does not hold the energy storage elements 100 by not including all of the walls.

[0092] In the above embodiment, bottom 411 of case 400 has step 411b, but it does not have to have step 411b. In this case, case end 411c may be the connection portion between bottom wall 411a and side portion 412.

[0093] In the above embodiment, the height of the case body 410 in the Z-axis direction is not particularly limited. That is, the case body 410 may be configured to have a sufficient height in the Z-axis direction to accommodate the power storage unit 10, and the power storage unit 10 may not protrude from the case body 410 in the positive direction of the Z-axis. The case body 410 may have a height of about two-thirds or half of the power storage unit 10 in the Z-axis direction, to accommodate a portion of the power storage unit 10 in the negative direction of the Z-axis, and to expose a portion of the power storage unit 10 in the positive direction of the Z-axis. In this case, the lid 420 may have a height of about one-third or half of the power storage unit 10 in the Z-axis direction, and to accommodate a portion of the power storage unit 10 in the positive direction of the Z-axis.

[0094] In the above embodiment, a plurality of power storage units 10 arranged in the X-axis direction may be housed inside the case 400. A plurality of power storage units 10 arranged in the Y-axis direction may be housed inside the case 400. When a plurality of power storage units 10 are housed in the case 400, 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.

[0095] In the above embodiment, the case 400 is provided with the case body 410 and the lid 420, but the lid 420 may not be provided.

[0096] In the above embodiment, the energy storage unit 10 may not include the spacer 200a or may not include the spacer 200b. When the energy storage unit 10 does not include the spacer 200b, it is sufficient that a member of the energy storage unit 10, such as the energy storage element 100, other than the spacer 200b, includes the convex portion 237.

[0097] Any combination of the components of the above-described embodiment and its modifications is also included within the scope of the present invention. [Industrial Applicability]

[0098] 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]

[0099] 1. Energy storage device 10 Energy storage unit 100 Energy storage element 110 Container 140 terminals 200, 200a, 200b spacers 210 Spacer body 220, 221, 222 Spacer wall 230, 231, 232, 233, 234, 235 Spacer protrusions 236 Projection Wall 237 Convex 300, 301 Sim 310 Shim body 320, 320a Shim protrusion 321, 325 middle section 322, 326 Restricted Section 323, 324, 410a opening 330 Shim end 400 cases 410 Case body 411 Bottom 411a Bottom wall 411b Step 411c Case end 412 Side 420 Lid

Claims

1. a power storage unit including a power storage element; a shim disposed adjacent to the power storage unit; a case that houses the power storage unit and the shim, the case includes a bottom portion on one side in a second direction that intersects with a first direction that is an arrangement direction of the power storage unit and the shim, the power storage unit includes a protrusion that protrudes toward the shim, The shim includes a limiting portion that is disposed on the other side of the protruding portion in the second direction and that limits movement of the shim toward the one side in the second direction relative to the power storage unit. Energy storage device.

2. the power storage unit further includes a spacer facing the shim; The convex portion is formed on the spacer. The power storage device according to claim 1 .

3. The limiting portion is a portion of the shim that protrudes in a third direction that intersects with the first direction and the second direction. The electricity storage device according to claim 1 or 2.

4. The shim has an opening formed therein into which the protrusion is inserted, The limiting portion is a portion of the shim that is located on the other side of the opening in the second direction. The electricity storage device according to claim 1 or 2.

5. The protrusion is disposed on the other side of the case in the second direction. The electricity storage device according to claim 1 or 2.

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