Energy storage device

Abstract

To provide a power storage device that can improve vibration resistance or impact resistance.SOLUTION: A power storage device 1 includes a power storage element 100 and a spacers 200 (holder 200a) arranged in a first direction, a case 300 has a case body 310 in which an opening 310a is formed on one side in a second direction perpendicular to the first direction, and houses the power storage element 100 and the spacer 200 (holder 200a). The spacer 200 (holder 200a) has a first opposing surface 231a facing the case 300 in a posture facing one side in the second direction. The case 300 has second opposing surfaces 312b and 313b facing the first opposing surface 231a in a posture facing the other side in the second direction. The second opposing surfaces 312b and 313b limit movement of the spacer 200 (holder 200a) to one side in the second direction by contacting the first opposing surface 231a.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to an electricity storage device including an electricity storage element, a spacer, and a case.

Background Art

[0002] Conventionally, an electricity storage device including an electricity storage element, a spacer, and a case that accommodates the electricity storage element and the spacer has been widely known. For example, Patent Document 1 discloses a power supply device (electricity storage device) in which prismatic battery cells (electricity storage elements) and separators (spacers) are accommodated in an outer case (case).

Prior Art

Patent Literature

[0003]

Patent Document 1

Summary of the Invention

Problem to be Solved by the Invention

[0004] In an electricity storage device in which an electricity storage element and a spacer are accommodated in a case, it is desired to restrict the movement of the electricity storage element and the spacer in the case and improve vibration resistance or impact resistance (resistance to external vibration or impact). However, in the electricity storage device having the above conventional configuration, the electricity storage element and the spacer move within the case, and there is a possibility that the improvement of vibration resistance or impact resistance cannot be achieved.

[0005] The present invention was made by the inventor of the present application by newly focusing on the above problem, and an object of the present invention is to provide an electricity storage device capable of improving vibration resistance or impact resistance.

Means for Solving the Problem

[0006] An energy storage device according to one aspect of the present invention comprises an energy storage device having energy storage elements and spacers arranged in a first direction, and a case body having an opening formed on one side in a second direction perpendicular to the first direction, and a case for housing the energy storage elements and the spacers, wherein the spacers have a first opposing surface facing the case in a position facing one side in the second direction, and the case has a second opposing surface facing the first opposing surface in a position facing the other side in the second direction, and the second opposing surface contacts the first opposing surface to restrict the movement of the spacers to one side in the second direction. [Effects of the Invention]

[0007] The energy storage device according to the present invention can improve vibration resistance or shock resistance. [Brief explanation of the drawing]

[0008] [Figure 1] This is a perspective view showing the configuration of the energy storage device according to the embodiment. [Figure 2] This is an exploded perspective view showing the energy storage element and spacer of the energy storage unit included in the energy storage device according to the embodiment. [Figure 3] This is a perspective view showing the configuration of the energy storage element according to the embodiment. [Figure 4] This is a perspective view showing the configuration of a spacer (holder) according to an embodiment. [Figure 5] These are perspective views and cross-sectional views showing the configuration of the case body according to the embodiment. [Figure 6] This is a cross-sectional view showing the positional relationship between the case body and the spacer (holder) according to the embodiment. [Figure 7] This is a perspective view showing the configuration of a spacer (holder) according to a modified example 1 of the embodiment. [Figure 8] This is a perspective view showing the configuration of a spacer (holder) according to a modified example 2 of the embodiment. [Modes for carrying out the invention]

[0009] An energy storage device according to one aspect of the present invention comprises an energy storage device having energy storage elements and spacers arranged in a first direction, and a case body having an opening formed on one side in a second direction perpendicular to the first direction, and a case for housing the energy storage elements and the spacers, wherein the spacers have a first opposing surface facing the case in a position facing one side in the second direction, and the case has a second opposing surface facing the first opposing surface in a position facing the other side in the second direction, and the second opposing surface contacts the first opposing surface to restrict the movement of the spacers to one side in the second direction.

[0010] According to this, in the energy storage device, the energy storage element and the spacer are housed in a case, and the second opposing surface of the case contacts the first opposing surface of the spacer, thereby restricting the movement of the spacer in one direction (towards the opening of the case body). In this way, the first and second opposing surfaces are arranged on the spacer and the case, restricting the spacer from moving towards the opening of the case body within the case. As a result, the movement of the spacer within the case is restricted, which in turn restricts the movement of the energy storage element along with the spacer, thereby improving the vibration resistance or shock resistance of the energy storage device.

[0011] The case body has a bottom wall positioned to face the second direction and a side wall positioned to face a third direction perpendicular to the first and second directions, and the second opposing surface may be provided on the side wall.

[0012] According to this, the second opposing surface of the case is provided on the side wall of the case body. This makes it easy to provide a second opposing surface on the case that restricts the movement of the spacer, thus easily realizing a configuration that improves the vibration resistance or shock resistance of the energy storage device.

[0013] One of the spacer and the case has a protrusion, and the other has a recess or through hole into which the protrusion is inserted, and the first opposing surface and the second opposing surface may be two surfaces that face each other in the second direction, having the protrusion and the recess or through hole.

[0014] According to this configuration, a convex portion is provided on one of the spacer and the case, and a concave portion or a through hole into which the convex portion is inserted is provided on the other, and the mutually opposing surfaces of the convex portion and the concave portion or the through hole are defined as a first opposing surface and a second opposing surface. With this arrangement, inserting the convex portion into the concave portion or the through hole allows the second opposing surface to be disposed at a position in contact with the first opposing surface, so that the movement of the spacer within the case can be restricted with a simple configuration. Accordingly, a configuration for improving the vibration resistance or impact resistance of the power storage device can be easily realized.

[0015] The power storage device may include a plurality of said spacers arranged in the first direction together with said power storage element, and each of said plurality of spacers may have said first opposing surface respectively.

[0016] According to this configuration, in the power storage device, each of the plurality of spacers has the first opposing surface, so that the second opposing surface of the case comes into contact with the plurality of first opposing surfaces of the plurality of spacers, thereby restricting the movement of the spacers. This allows the movement of the plurality of spacers within the case to be restricted, so that the vibration resistance or impact resistance of the power storage device can be further improved.

[0017] Said second opposing surface may be a surface that is continuous across said plurality of first opposing surfaces provided on said plurality of spacers.

[0018] According to this configuration, the second opposing surface of the case is formed continuously across the plurality of first opposing surfaces provided on the plurality of spacers. This eliminates the need to form a plurality of second opposing surfaces on the case, so that the second opposing surface can be formed on the case with a simple configuration. Accordingly, the movement of the plurality of spacers within the case can be restricted with a simple configuration, so that a configuration for improving the vibration resistance or impact resistance of the power storage device can be easily realized.

[0019] At least one of said spacer and said case may include a deformable portion that deforms so that at least one of said first opposing surface and said second opposing surface is movable relative to the other in a third direction orthogonal to said first direction and said second direction.

[0020] According to this aspect, since at least one of the spacer and the case has the deformable portion, when the spacer is inserted into the case, the distance between the first opposing surface and the second opposing surface in the third direction can be adjusted by the deformable portion. This can suppress insertion difficulty caused by a portion having the first opposing surface hitting the case or a portion having the second opposing surface hitting the spacer when inserting the spacer into the case. Therefore, the spacer can be easily inserted into the case, and the second opposing surface can be easily arranged at a position in contact with the first opposing surface, so that a configuration for improving the vibration resistance or impact resistance of the power storage device can be easily realized.

[0021] The power storage device includes two power storage elements that sandwich the spacer in the first direction, and the first opposing surface may be arranged between the two power storage elements in the first direction.

[0022] When inserting the spacer into the case, or when the power storage device receives external vibration, impact or the like, the portion of the spacer provided with the first opposing surface may move toward the inside of the case. For this reason, the first opposing surface of the spacer is arranged between the two power storage elements. Thereby, even when the portion of the spacer provided with the first opposing surface moves toward the inside of the case, contact with (compression of) the power storage elements can be suppressed. Therefore, the vibration resistance or impact resistance of the power storage device can be improved while suppressing the influence on the power storage elements.

[0023] Hereinafter, a power storage device according to an embodiment of the present invention (including modifications thereof) will be described with reference to the drawings. All of the embodiments described below are illustrative of general or specific examples. Numerical values, shapes, materials, constituent elements, arrangement positions and connection modes of constituent elements, manufacturing steps, order of manufacturing steps, and the like shown in the following embodiments are merely examples, and are not intended to limit the present invention. In each drawing, dimensions and the like are not strictly illustrated. In each drawing, identical or similar constituent elements are denoted by the same reference numerals.

[0024] In the following description and drawings, the direction in which the pair of electrode terminals of an energy storage element are aligned, the direction in which the pair of short sides of the energy storage element's container are opposed, or the direction in which the energy storage unit is aligned is defined as the X-axis direction. The direction in which the pair of long sides of the energy storage element's container are opposed, the thickness direction (flattening direction) of the energy storage element's container, the direction in which the multiple energy storage elements of an energy storage unit are aligned, or the direction in which the energy storage elements and spacers (holders) of an energy storage unit are aligned is defined as the Y-axis direction. The direction in which the electrode terminals of an energy storage element protrude, the direction in which the container body and the container lid of an energy storage element are aligned, the direction in which the case body and the lid of a case are aligned, the direction in which the opening and bottom wall of the case body are opposed, or the vertical direction is defined as the Z-axis direction. These X-axis, Y-axis, and Z-axis directions intersect each other (orthogonal in this embodiment). Depending on the usage, the Z-axis direction may not be the vertical direction, but for the sake of explanation below, the Z-axis direction will be described as the vertical direction.

[0025] In the following explanation, the X-axis positive direction refers to the direction of the X-axis arrow, and the X-axis negative direction refers to the opposite direction. When simply referring to the X-axis direction, it refers to either the X-axis positive direction or the X-axis negative direction, or one of them. When referring to one side and the other side of the X-axis direction, it refers to one and the other of the X-axis positive direction and the X-axis negative direction. The same applies to the Y-axis direction and the Z-axis direction. In the following, the Y-axis direction will also be called the first direction, the Z-axis direction the second direction, and the X-axis direction the third direction. Expressions indicating relative directions or orientations, such as parallel and orthogonal, include cases where they are not strictly those directions or orientations. For example, two directions being parallel means not only that the two directions are perfectly parallel, but also that they are substantially parallel, i.e., that they include a difference of, for example, a few percent. In the following explanation, when the term "insulation" is used, it means "electrical insulation".

[0026] (Embodiment) [1. Description of Energy Storage Device 1] First, the general configuration of the energy storage device 1 in this embodiment will be described. Figure 1 is a perspective view showing the configuration of the energy storage device 1 according to this embodiment. In Figure 1, the lid 320 has been removed from the case body 310 of the case 300 in the energy storage device 1. As a result, Figure 1 shows two energy storage units 10 arranged inside the case 300. Figure 2 is an exploded perspective view showing the energy storage elements 100 and spacers 200 of the energy storage unit 10 in the energy storage device 1 according to this embodiment. Figure 2 shows the components of the energy storage unit 10 disassembled, illustrating two of the energy storage elements 100 and three spacers 200 (holders 200a).

[0027] The energy storage device 1 is a device that can charge electricity from an external source and discharge electricity to an external source. The energy storage device 1 is used for power storage or power supply purposes. The energy storage device 1 is used as a battery for driving or starting the engine of mobile vehicles such as automobiles, motorcycles, watercraft, ships, snowmobiles, agricultural machinery, construction machinery, or railway vehicles for electric railways. Examples of automobiles include electric vehicles (EVs), hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), and fossil fuel (gasoline, diesel, liquefied natural gas, etc.) vehicles. Examples of railway vehicles for electric railways include electric trains, monorails, maglev trains, and hybrid trains equipped with both diesel engines and electric motors. The energy storage device 1 can also be used as a stationary battery for household or commercial use.

[0028] As shown in Figure 1, the energy storage device 1 comprises an energy storage unit 10 and a case 300 that houses the energy storage unit 10. The energy storage device 1 also includes external terminals (positive external terminal and negative external terminal) for electrically connecting to external devices, but their illustration and description are omitted. In addition to the above components, the energy storage device 1 may also include a circuit board and electrical equipment such as relays for monitoring or controlling the charging and discharging states of the energy storage unit 10.

[0029] The energy storage unit 10 is a battery module (battery pack) having a plurality of energy storage elements 100. The energy storage unit 10 has a roughly rectangular parallelepiped shape that is long in the Y-axis direction, as the plurality of energy storage elements 100 are arranged alternately with spacers 200 in the Y-axis direction (first direction). In this embodiment, two energy storage units 10 arranged in the X-axis direction are housed inside the case 300. The energy storage unit 10 has a plurality of energy storage elements 100 and a plurality of spacers 200 (holders 200a, 200b, and 200c). The energy storage unit 10 also includes busbars for connecting the energy storage elements 100 in series or parallel, a busbar frame for holding the busbars, and busbars for connecting the energy storage elements 100 to external terminals, but these are not shown in the illustration. The busbars may connect all the energy storage elements 100 in series, or any of the energy storage elements 100 may be connected in parallel and then connected in series, or all the energy storage elements 100 may be connected in parallel.

[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 flattened rectangular parallelepiped shape (square, prism) in the Y-axis direction. In this embodiment, multiple energy storage elements 100 are arranged in line in the Y-axis direction, but the number of energy storage elements 100 arranged is not particularly limited; it may be one, several dozen, or more. The size and shape of the energy storage element 100 are also not particularly limited; it may be an elongated cylindrical shape, an elliptical cylindrical shape, a cylindrical shape, a polygonal prism shape other than a rectangular parallelepiped, etc. The energy storage element 100 is not limited to a non-aqueous electrolyte secondary battery; it may be a secondary battery other than a non-aqueous electrolyte secondary battery, or it may be a capacitor. The energy storage element 100 may not be a secondary battery, but a primary battery that allows the user to use the stored electricity without charging. 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 flattened member in the Y-axis direction, positioned alongside the energy storage element 100 in the Y-axis direction, and insulating and / or heat-insulating the energy storage element 100 from other members. The spacer 200 is an insulating or heat-insulating plate positioned in the positive or negative Y-axis direction of the energy storage element 100, and insulating and / or heat-insulating the energy storage elements 100 from each other or from the energy storage element 100 to the case 300. Spacer 200 is formed from insulating materials 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), polyetheretherketone (PEEK), tetrafluoroethylene perfluoroalkyl vinyl ether (PFA), polytetrafluoroethylene (PTFE), polyethersulfone (PES), polyamide (PA), ABS resin, or composite materials thereof, or from insulating materials such as mica.

[0032] The spacer 200 has walls on both sides of the energy storage element 100 in the X-axis direction and on both sides of the Z-axis direction, thereby holding the energy storage element 100 and functioning as a holder for positioning the energy storage element 100. For this reason, the spacer 200 positioned at the center position in the Y-axis direction of the energy storage unit 10 (between the two energy storage elements 100 at the center position) is referred to as holder 200b. The spacers 200 positioned at both ends in the Y-axis direction of the energy storage unit 10 (between the end energy storage elements 100 and the case 300) are referred to as holder 200c. The spacer 200 positioned between holder 200b and holder 200c (between the two energy storage elements 100 other than the center position) is referred to as holder 200a. Holders 200a, 200b, and 200c are arranged alternately with the energy storage elements 100. Figure 2 shows a configuration in which the energy storage elements 100 and holders 200a are arranged alternately, but the energy storage elements 100 and holders 200b and 200c are also arranged alternately in a similar manner.

[0033] Specifically, as shown in Figure 2, holder 200a is an intermediate holder (intermediate spacer) that holds two energy storage elements 100 arranged on both sides of the holder 200a in the Y-axis direction, with walls on both sides of the X-axis direction and the Z-axis direction of the two energy storage elements 100. Similarly, holder 200b is a center plate (center holder or center spacer) that holds two energy storage elements 100 arranged on both sides of the holder 200b in the Y-axis direction, with walls on both sides of the X-axis direction and the Z-axis direction of the two energy storage elements 100. Holder 200b has the function of increasing the rigidity of the energy storage unit 10 which is long in the Y-axis direction. Holder 200c is an end holder (end spacer) that holds one energy storage element 100 arranged on one side of holder 200c in the Y-axis direction, with walls on both sides of the X-axis direction and the Z-axis direction of the one energy storage element 100.

[0034] In other words, the energy storage element 100 located in the center of the energy storage unit 10 in the Y-axis direction is held by holders 200a and 200b. The energy storage element 100 located at the ends of the energy storage unit 10 in the Y-axis direction is held by holders 200a and 200c. The remaining energy storage elements 100 are held by the two holders 200a. All spacers 200 (holders 200a, 200b, and 200c) may be made of the same material, or any of the spacers 200 may be made of a different material.

[0035] The case 300 is a roughly rectangular parallelepiped (box-shaped) container that constitutes the outer casing (shell) of the energy storage device 1. The case 300 is positioned outside the energy storage unit 10, fixing the energy storage unit 10 in a predetermined position and protecting it from impacts, etc. The case 300 is a metal case formed from a metal component such as aluminum, aluminum alloy, stainless steel, iron, or plated steel sheet. In this embodiment, the case 300 is formed from die-cast aluminum (aluminum die-cast). The case 300 may also be formed from an insulating component such as any resin material that can be used for the spacer 200 of the energy storage unit 10.

[0036] As shown in Figure 1, the case 300 comprises a case body 310 that constitutes the main body of the case 300 and a cover 320 that constitutes the cover of the case 300. The case body 310 is a housing with an opening 310a formed in the Z-axis positive direction (one side of the second direction perpendicular to the first direction) and houses the energy storage unit 10 (energy storage element 100 and spacers 200 (holders 200a, 200b, and 200c)). The cover 320 is a flat rectangular member that closes the opening 310a of the case body 310. The case body 310 has two rectangular openings 310a arranged in the X-axis direction, and after the energy storage unit 10 is inserted through each opening 310a, the case body 310 and the cover 320 are joined by bolts, welding, adhesive, etc. This results in a sealed structure inside the case 300. The case body 310 or the lid 320 may have a terminal block for external terminals (positive external terminal and negative external terminal) attached to it, and the external terminals may be arranged on the terminal block.

[0037] Next, the configuration of the energy storage element 100, the spacer 200 (especially the holder 200a), and the case 300 (especially the case body 310) will be described in detail.

[0038] [1.1 Description of the energy storage element 100] Figure 3 is a perspective view showing the configuration of the energy storage element 100 according to this embodiment. Figure 3 shows an enlarged view of the energy storage element 100 shown in Figure 2. Since all of the multiple energy storage elements 100 in the energy storage unit 10 have the same configuration, Figure 3 shows one energy storage element 100, and the configuration of this one energy storage element 100 will be described in detail below.

[0039] As shown in Figure 3, the energy storage element 100 has a container 110 and a pair of electrode terminals 140 (positive and negative). Inside the container 110 are the electrode body, the pair of current collectors (positive and negative), and the electrolyte (non-aqueous electrolyte). A gasket is placed between the electrode terminals 140 and the current collectors and the container 110, but these are not shown in the illustration. There are no particular restrictions on the type of electrolyte 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 material as long as it has insulating properties. In addition to the above components, the energy storage element 100 may also have a spacer placed to the side of the electrode body, an insulating film that encloses the electrode body, etc., and an insulating film (shrink tubing, etc.) that covers the outer surface of the container 110.

[0040] The container 110 is a rectangular parallelepiped (square or box-shaped) case having a container body 120 with an opening 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 on the Z-axis positive side. The container lid 130 is a rectangular plate-shaped member that is long in the X-axis direction and constitutes the lid of the container 110, and is positioned in the Z-axis positive direction of the container body 120. The container lid 130 is provided with a gas discharge valve 131 that releases pressure when the pressure inside the container 110 rises excessively, and an injection part (not shown) for injecting electrolyte into the container 110. The material of the container 110 (container body 120 and container lid 130) is not particularly limited and can be made of weldable (joinable) metals such as stainless steel, aluminum, aluminum alloy, iron, plated steel sheet, etc., but resin can also be used.

[0041] The container 110 is sealed inside by welding or other means to the container body 120 after the electrode body and other components are housed inside the container body 120. 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 on the Z-axis negative side. The long sides 111 are rectangular planar portions that form the long sides of the container 110 and are positioned 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 planar portions that form the short sides of the container 110 and are positioned opposite the walls of the spacers 200 and the case 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 surface that forms the bottom of the container 110, and is positioned opposite the wall of the spacer 200 and the bottom wall of the case 300 in the Z-axis direction. The bottom surface 113 is positioned adjacent to the long side surface 111 and the short side surface 112.

[0042] The electrode terminals 140 are terminal members (positive and negative electrode terminals) of the energy storage element 100, positioned on the container lid 130. Specifically, the electrode terminals 140 are positioned so as to protrude in the positive Z-axis direction from the upper surface (terminal placement surface) of the container lid 130. The electrode terminals 140 are electrically connected to the positive and negative electrode plates of the electrode body via a current collector. In other words, the electrode terminals 140 are metal members that lead the 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 electrode terminals 140 are made of aluminum, aluminum alloy, copper, copper alloy, etc.

[0043] The electrode body is an energy storage element (power generation element) formed by laminating a positive electrode plate, a negative electrode plate, and a separator. The positive electrode plate has a positive electrode active material layer formed on a positive electrode base layer which is a current collector foil made of a metal such as aluminum or an aluminum alloy. The negative electrode plate has a negative electrode active material layer formed on a negative electrode base layer which is a current collector foil made of a metal such as copper or a copper alloy. As for the active material used in the positive electrode active material layer and the negative electrode active material layer, any known material can be used as long as it is capable of intercalating and releasing lithium ions. The separator can be a microporous sheet or nonwoven fabric made of resin. In this embodiment, the electrode body is formed by laminating electrode plates (positive electrode plate and negative electrode plate) in the Y-axis direction. The electrode body may be of any form, such as a wound electrode body formed by winding electrode plates (positive electrode plate and negative electrode plate), a laminated (stacked) electrode body formed by laminating a plurality of flat electrode plates, or a bellows-type electrode body in which the electrode plates are folded in a bellows shape.

[0044] The current collector is a conductive current collector (positive electrode current collector and negative electrode current collector) that is electrically and mechanically connected to the electrode terminals 140 and the electrode body. The positive electrode current collector is made of aluminum or an aluminum alloy, similar to the positive electrode base layer of the positive electrode plate of the electrode body, and the negative electrode current collector is made of copper or a copper alloy, similar to the negative electrode base layer of the negative electrode plate of the electrode body.

[0045] [1.2 Description of Spacer 200 (Holder 200a)] Next, the configuration of the holder 200a among the spacers 200 will be described in detail. Figure 4 is a perspective view showing the configuration of the spacer 200 (holder 200a) according to this embodiment. Specifically, Figure 4(a) shows an enlarged view of the holder 200a shown in Figure 2, and Figure 4(b) shows a further enlarged view of the movement limiting portion 230 and its surrounding configuration of the holder 200a shown in Figure 4(a). Since all of the multiple holders 200a of the energy storage unit 10 have the same configuration, Figure 4 shows one holder 200a, and below, the configuration of one holder 200a will be described in detail.

[0046] As shown in Figure 4, the holder 200a has similar shapes at both ends in the X-axis direction. In other words, the holder 200a has a shape that is symmetrical with respect to a plane passing through the center position and parallel to the YZ plane. The holder 200a includes a holder body 210, a holder wall portion 220, and a movement limiting portion 230.

[0047] The holder body 210 is a flat, rectangular portion that constitutes the main body of the holder 200a and is arranged parallel to the XZ plane. In this embodiment, the holder body 210 is positioned facing the long side 111 in the Y-axis direction and in contact with the long side 111, so as to cover the entire surface of the long side 111 of the container 110 of the energy storage element 100 in the Y-axis positive or Y-axis negative direction of the energy storage element 100. The holder body 210 has a plurality of L-shaped curved grooves through which a cooling gas (air) passes.

[0048] The holder wall portion 220 is a wall positioned on both sides of the energy storage element 100 in the Z-axis direction and on both sides of the X-axis direction. Specifically, the holder wall portion 220 has a pair of first holder wall portions 221 and 222 positioned on both sides of the energy storage element 100 in the Z-axis direction (second direction), and a pair of second holder wall portions 223 and a pair of second holder wall portions 224 positioned on both sides of the energy storage element 100 in the X-axis direction (third direction perpendicular to the first and second directions).

[0049] The first holder wall portion 221 is a flat plate-shaped portion that protrudes in the Y-axis direction from the Z-axis positive end of the holder body 210 and is arranged parallel to the XY plane. Specifically, a pair of first holder wall portions 221 are arranged at both ends of the holder 200a in the X-axis direction, protruding in both directions in the Y-axis direction from both ends of the Z-axis positive end of the holder body 210. The first holder wall portion 221 is arranged along the container lid portion 130 of the container 110 of the energy storage element 100 in the Z-axis positive direction. More specifically, the first holder wall portion 221 is arranged opposite the container lid portion 130 in the Z-axis direction at both ends of the energy storage element 100 in the X-axis direction, so as to cover approximately half of the container lid portion 130 on the Y-axis positive side or the Y-axis negative side.

[0050] The first holder wall portion 222 is a flat plate-shaped portion that protrudes in the Y-axis direction from the Z-axis negative end of the holder body 210 and extends in the X-axis direction, and is arranged parallel to the XY plane. Specifically, the first holder wall portion 222 is arranged extending in the X-axis direction, protruding on both sides in the Y-axis direction, from one end to the other in the X-axis direction at the Z-axis negative end of the holder body 210. The first holder wall portion 222 is arranged along the bottom surface 113 of the container 110 of the energy storage element 100 in the Z-axis negative direction. More specifically, the first holder wall portion 222 is arranged facing the bottom surface 113 in the Z-axis direction, so as to cover approximately half of the bottom surface 113 on the Y-axis positive side or the Y-axis negative side, from one end to the other in the X-axis direction of the bottom surface 113.

[0051] The second holder wall portion 223 is a flat plate-shaped portion that protrudes in the Y-axis direction from the X-axis end and Z-axis positive end of the holder body 210, and is arranged parallel to the YZ plane. Specifically, a pair of second holder wall portions 223 are arranged at both ends of the holder 200a in the X-axis direction, protruding on both sides in the Y-axis direction from the Z-axis positive ends of both ends of the holder body 210 in the X-axis direction. The second holder wall portion 223 is arranged along the short side 112 of the container 110 of the energy storage element 100. More specifically, the second holder wall portion 223 is arranged opposite the short side 112 in the X-axis direction at the Z-axis positive ends on both sides of the energy storage element 100 in the X-axis direction, so as to cover approximately half of the Y-axis positive side or the Y-axis negative side of the short side 112.

[0052] The second holder wall portion 224 is a flat plate-shaped portion that protrudes in the Y-axis direction from the X-axis end and Z-axis negative end of the holder body 210, and is arranged parallel to the YZ plane. Specifically, a pair of second holder wall portions 224 are arranged at both ends of the holder 200a in the X-axis direction, protruding on both sides in the Y-axis direction from the Z-axis negative ends of both ends of the holder body 210 in the X-axis direction. The second holder wall portion 224 is arranged along the short side 112 of the container 110 of the energy storage element 100. More specifically, the second holder wall portion 224 is arranged opposite the short side 112 in the X-axis direction at the Z-axis negative ends on both sides of the energy storage element 100 in the X-axis direction, so as to cover approximately half of the Y-axis positive side or the Y-axis negative side of the short side 112.

[0053] In this way, the holder wall portion 220 is positioned to 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. As a result, the holder 200a holds the energy storage element 100.

[0054] The movement-restricting portion 230 is a part that restricts the movement of the holder 200a in the Z-axis positive direction (one side of the second direction) by contacting the case 300. In this embodiment, the movement-restricting portion 230 is provided on each of the pair of second holder wall portions 223 on both sides in the X-axis direction. That is, the movement-restricting portion 230 is located at both ends of the holder 200a in the X-axis direction and at the Z-axis positive end. Specifically, a rectangular through hole 223a that penetrates in the X-axis direction is formed in the second holder wall portion 223, and the movement-restricting portion 230 is located within the through hole 223a. Alternatively, a rectangular recess that is recessed in the X-axis direction may be formed in the second holder wall portion 223, and the movement-restricting portion 230 may be located within this recess. Each movement-restricting portion 230 has a convex portion 231 and a deformable portion 232.

[0055] The protrusion 231 is a projection (claw) that protrudes in the X-axis direction from the Z-axis negative end of the deformable portion 232. Specifically, the movement restricting portion 230 provided on the second holder wall portion 223 in the X-axis positive direction has a protrusion 231 that protrudes in the X-axis positive direction, and the movement restricting portion 230 provided on the second holder wall portion 223 in the X-axis negative direction also has a protrusion 231 that protrudes in the X-axis negative direction. Each protrusion 231 has a first opposing surface 231a on the Z-axis positive direction surface, which is a plane (flat surface) parallel to the XY plane. The first opposing surface 231a is the surface that faces the case 300 in an orientation facing the Z-axis positive direction (one side of the second direction) (see Figure 6).

[0056] The deformable portion 232 is a part that deforms to be movable in the X-axis direction (third direction) relative to the first opposing surface 231a. The deformable portion 232 is located inside the through hole 223a of the second holder wall portion 223 and is a flat, rectangular portion that extends from the Z-axis positive edge of the through hole 223a in the Z-axis negative direction. It can also be said that the deformable portion 232 is formed by providing two slits aligned in the Y-axis direction in the second holder wall portion 223 from both ends of the convex portion 231 in the Y-axis direction toward the Z-axis positive direction. As a result, the deformable portion 232 deforms so as to bend in the X-axis direction, making the convex portion 231 (first opposing surface 231a) movable in the X-axis direction.

[0057] [1.3 Description of Case Body 310] Next, the configuration of the case body 310 of the case 300 will be described in detail. Figure 5 is a perspective view and a cross-sectional view showing the configuration of the case body 310 according to this embodiment. Specifically, Figure 5(a) is a perspective view showing the configuration of the case body 310, and Figure 5(b) is a cross-sectional view showing the case body 310 shown in Figure 5(a) when cut by a plane passing through the Vb-Vb line and parallel to the XZ plane. Figure 6 is a cross-sectional view showing the positional relationship between the case body 310 and the spacer 200 (holder 200a) according to this embodiment. Specifically, Figure 6(a) is a cross-sectional view showing the case body 310 when cut by a plane parallel to the XZ plane with the holder 200a placed on the case body 310. Figure 6(b) is an enlarged cross-sectional view showing the configuration of the movement limiting portion 230 and its surroundings in the case body 310 and holder 200a shown in Figure 6(a) when cut by a plane parallel to the XZ plane. Since the case body 310 has the same configuration in the positive X-axis direction and the negative X-axis direction, Figure 6 illustrates the positive X-axis direction, and the following explanation of Figure 6 will be given with respect to that positive X-axis direction.

[0058] As shown in Figure 5, the case body 310 has a bottom wall 311 and case wall portions 312, 313, and 314. In other words, the case body 310 has a bottom wall 311 on the bottom surface in the negative Z-axis direction (the other side of the second direction), a pair of case wall portions 312 on the side surfaces on both sides in the X-axis direction, a case wall portion 313 in the center in the X-axis direction, and a pair of case wall portions 314 on the side surfaces on both sides in the Y-axis direction. The case body 310 is a single component in which the bottom wall 311, the two case wall portions 312, the case wall portion 313, and the two case wall portions 314 are integrated. That is, the case body 310 is integrally formed as a single component (single part) by integral molding using aluminum die casting or the like.

[0059] The bottom wall 311 is a flat, rectangular wall portion parallel to the XY plane and elongated in the Y-axis direction, positioned with its main surface facing the Z-axis direction (second direction), forming the bottom surface of the case body 310. The bottom wall 311 is positioned opposite the energy storage unit 10 (energy storage element 100 and spacers 200 (holders 200a, 200b, and 200c)) in the Z-axis direction. Specifically, the bottom wall 311 is positioned in the Z-axis direction of the energy storage unit 10 so as to cover the entire surface of the Z-axis negative direction of the energy storage unit 10, and supports the energy storage unit 10 from the Z-axis negative direction. The bottom wall 311 is positioned adjacent to the case wall portions 312, 313, and 314.

[0060] The case wall portion 312 is a flat, rectangular wall portion (side wall) that is parallel to the YZ plane and elongated in the Y-axis direction, with its main surface facing the X-axis direction (third direction), forming the X-axis side surface (long side surface) of the case body 310. The case wall portion 312 is a wall portion that rises in the Z-axis positive direction from the X-axis end of the bottom wall 311, and is positioned opposite the energy storage unit 10 (energy storage element 100 and spacers 200 (holders 200a, 200b, and 200c)) in the X-axis direction (third direction). The case wall portion 312 is adjacent to the bottom wall 311 and the case wall portion 314. In this embodiment, two case wall portions 312 are positioned opposite each other at both ends of the case body 310 in the X-axis direction. The case wall portion 312 in the X-axis positive direction is positioned in the X-axis positive direction of the energy storage unit 10 so as to cover the entire surface of the X-axis positive direction of the energy storage unit 10 in the X-axis positive direction. The case wall portion 312 in the negative X-axis direction is positioned in the negative X-axis direction of the energy storage unit 10 so as to cover the entire surface of the energy storage unit 10 in the negative X-axis direction.

[0061] The case wall 313 is a rectangular parallelepiped-shaped wall that is elongated in the Y-axis direction and is positioned with its main surface facing the X-axis direction (third direction), partitioning the space inside the case body 310. The case wall 313 is a wall that rises from the center of the bottom wall 311 in the X-axis direction in the Z-axis direction, and is positioned opposite the energy storage unit 10 (energy storage element 100 and spacers 200 (holders 200a, 200b, and 200c)) in the X-axis direction (third direction). Specifically, the case wall 313 is positioned between two energy storage units 10 that are aligned in the X-axis direction. In other words, the energy storage device 1 comprises an energy storage element 100 and other energy storage elements 100 housed in the case 300 and aligned with the energy storage element 100 in the X-axis direction (third direction). The case wall 313 is a wall positioned inside the case 300 between the energy storage element 100 and the other energy storage elements 100. As a result, the case wall portion 313 is positioned in the negative X-axis direction of the energy storage unit 10 so as to cover the entire surface of the energy storage unit 10 in the negative X-axis direction, which is in the positive X-axis direction. The case wall portion 313 is positioned in the positive X-axis direction of the energy storage unit 10 so as to cover the entire surface of the energy storage unit 10 in the positive X-axis direction, which is in the negative X-axis direction. The case wall portion 313 is adjacent to the bottom wall 311 and the case wall portion 314.

[0062] The case wall portion 314 is a flat, rectangular wall portion (side wall) that is parallel to the XZ plane and elongated in the X-axis direction, with its main surface facing the Y-axis direction (first direction), forming the Y-axis side (short side) of the case body 310. The case wall portion 314 is a wall portion that rises in the Z-axis positive direction from the Y-axis end of the bottom wall 311, and is positioned opposite the energy storage unit 10 (holder 200c of the spacer 200) in the Y-axis direction (first direction). The case wall portion 314 is adjacent to the bottom wall 311, and the case wall portions 312 and 313. In this embodiment, two case wall portions 314 are positioned opposite each other at both ends of the case body 310 in the Y-axis direction. The case wall portion 314 in the Y-axis positive direction is positioned in the Y-axis positive direction of the energy storage unit 10 (holder 200c) so as to cover almost the entire surface of the Y-axis positive direction of the energy storage unit 10 (holder 200c). The case wall portion 314 in the negative Y-axis direction is positioned in the negative Y-axis direction of the energy storage unit 10 (holder 200c) so as to cover almost the entire surface of the energy storage unit 10 (holder 200c in the negative Y-axis direction).

[0063] With the above configuration, the case body 310 has an opening 310a that opens toward the Z-axis positive direction (one side of the second direction). In other words, the two case wall sections 312, case wall section 313, and two case wall sections 314 form two openings 310a aligned in the X-axis direction. The opening 310a is a rectangular opening that is elongated in the Y-axis direction when viewed from the Z-axis direction, and is positioned opposite the bottom wall 311 of the case body 310. The opening 310a is positioned opposite the energy storage unit 10 in the Z-axis direction and is formed to a size that allows the energy storage unit 10 to pass through in the Z-axis direction. In other words, the opening 310a is an opening on the Z-axis positive side of the case body 310.

[0064] A recess 312a is formed on the surface of the case wall 312 facing the energy storage unit 10, closer to the positive Z-axis direction, and recessed in the X-axis direction. In other words, in the case wall 312 in the positive X-axis direction, a recess 312a is formed on the surface in the negative X-axis direction, closer to the positive Z-axis direction. In the case wall 312 in the negative X-axis direction, a recess 312a is formed on the surface in the positive X-axis direction, closer to the positive Z-axis direction. The recess 312a is a rectangular recess (groove) that extends in the Y-axis direction from one end to the other of the case wall 312 in the Y-axis direction, and is viewed from the Y-axis direction. The recess 312a has a second opposing surface 312b on its inner surface in the positive Z-axis direction, which is a plane (flat surface) parallel to the XY plane.

[0065] Similarly, a recess 313a is formed on the surface of the case wall 313 facing the energy storage unit 10, closer to the positive Z-axis direction. In other words, on the case wall 313 closer to the positive Z-axis direction, a recess 313a is formed on the surface in the positive X-axis direction, and a recess 313a is formed on the surface in the negative X-axis direction. The recess 313a is a rectangular recess (groove) that extends in the Y-axis direction from one end to the other of the case wall 313 in the Y-axis direction, as viewed from the Y-axis direction. The recess 313a has a second opposing surface 313b on its inner surface in the positive Z-axis direction, which is a plane (flat surface) parallel to the XY plane. Thus, the second opposing surfaces 312b and 313b of the recesses 312a and 313a are provided on the side walls (case wall portions 312 and 313) located on the sides of the case body 310 where the energy storage unit 10 is located.

[0066] As shown in Figure 6, a pair of protrusions 231 provided on a pair of movement-restricting portions 230 of the holder 200a are inserted into the recesses 312a and 313a. In other words, the holder 200a of the spacer 200 has protrusions 231, and the case 300 has recesses 312a and 313a into which the protrusions 231 are inserted. As a result, the first opposing surface 231a of the pair of protrusions 231 and the second opposing surfaces 312b and 313b of the recesses 312a and 313a face each other in the Z-axis direction. That is, the first opposing surface 231a and the second opposing surfaces 312b and 313b are two surfaces of the protrusions 231 and recesses 312a and 313a that face each other in the Z-axis direction (second direction). Specifically, the second opposing surface 312b is the surface that faces the first opposing surface 231a in the negative Z-axis direction (the other side of the second direction). The second opposing surface 313b is the surface that faces the first opposing surface 231a, with its orientation facing the negative Z-axis direction (the other side of the second direction).

[0067] During the process in which the protrusion 231 is inserted into the recess 312a or 313a, the deformable portion 232 deforms so that the first opposing surface 231a is movable relative to the second opposing surface 312b or 313b in the X-axis direction (third direction). In other words, when the holder 200a is inserted into the case body 310 from the opening 310a of the case body 310, the pair of protrusions 231 come into contact with the edge of the opening 310a, and the deformable portion 232 deforms so that the pair of protrusions 231 move closer to each other in the X-axis direction. Then, when the pair of protrusions 231 are inserted into the recesses 312a and 313a, the deformable portion 232 deforms so that the pair of protrusions 231 move further apart from each other in the X-axis direction. In this way, the deformable portion 232 deforms so that the protrusion 231 (first opposing surface 231a) is movable in the X-axis direction. In other words, the deformable portion 232 deforms in the X-axis direction such that the convex portion 231 (first opposing surface 231a) is movable relative to the concave portion 312a or 313a (second opposing surface 312b or 313b).

[0068] When the convex portion 231 is inserted into the recess 312a or 313a, the second opposing surface 312b or 313b contacts the first opposing surface 231a, thereby restricting the movement of the spacer 200 (holder 200a) in the Z-axis positive direction (one side of the second direction). In this embodiment, the second opposing surface 312b or 313b is in contact with the first opposing surface 231a, restricting the movement of the holder 200a in the Z-axis positive direction. The second opposing surface 312b or 313b does not necessarily have to be in contact with the first opposing surface 231a; it is sufficient if it is located near the first opposing surface 231a (there may be a small gap between it and the first opposing surface 231a). Even in this case, the second opposing surface 312b or 313b can restrict the movement of the holder 200a in the Z-axis positive direction if the holder 200a moves slightly in the Z-axis positive direction and comes into contact with the first opposing surface 231a (when contact occurs). Thus, the second opposing surface 312b or 313b should be configured to restrict the movement of the holder 200a (perform positioning) when it comes into contact with the first opposing surface 231a. The second opposing surface 312b or 313b can also be described as a movement restricting part that restricts the movement of the holder 200a in the Z-axis positive direction, or a positioning part that positions the holder 200a.

[0069] In this embodiment, the energy storage device 1 includes a plurality of spacers 200 (a plurality of holders 200a) arranged in the Y-axis direction (first direction) together with the energy storage element 100, and each of the plurality of spacers 200 (a plurality of holders 200a) has a first opposing surface 231a of the protrusion 231. The second opposing surfaces 312b and 313b are surfaces that are continuous across the plurality of first opposing surfaces 231a of the plurality of spacers 200 (a plurality of holders 200a). In other words, the second opposing surfaces 312b and 313b contact the plurality of first opposing surfaces 231a of the plurality of holders 200a, thereby restricting the movement of the plurality of holders 200a in the Z-axis positive direction.

[0070] [2. Explanation of Effects] As described above, in the energy storage device 1 according to this embodiment, the energy storage element 100 and the spacer 200 (holder 200a) are housed in the case 300. The second opposing surfaces 312b and 313b of the case 300 contact the first opposing surface 231a of the spacer 200 (holder 200a), thereby restricting the movement of the spacer 200 (holder 200a) toward one side in the second direction (the positive Z-axis direction, toward the opening 310a of the case body 310). In this way, the first opposing surface 231a and the second opposing surfaces 312b and 313b are arranged on the spacer 200 (holder 200a) and the case 300, thereby restricting the movement of the spacer 200 (holder 200a) toward the opening 310a of the case body 310 within the case 300. This restricts the movement of the spacer 200 (holder 200a) within the case 300, thereby preventing the energy storage element 100 from moving along with the spacer 200 (holder 200a), and improving the vibration resistance or shock resistance of the energy storage device 1.

[0071] By positioning the first opposing surface 231a and the second opposing surfaces 312b and 313b on the spacer 200 (holder 200a) and case 300, the spacer 200 (holder 200a) can be positioned relative to the case 300. This improves the positioning of the energy storage element 100 and the spacer 200 (holder 200a) when inserting them into the case 300. In particular, the energy storage unit 10 has a long length in the Y-axis direction and is difficult to position relative to the case 300, so the effect of improving positioning is significant. The movement of the spacer 200 (holder 200a) within the case 300 can be restricted without providing joining members such as bolts and nuts. Therefore, there is no need for space to place joining members, nor is there space to place tools for joining the joining members, thus saving space in the energy storage device 1. The same applies to the following.

[0072] The second opposing surfaces 312b and 313b of case 300 are provided on the side walls (case wall portions 312 and 313) of the case body 310. This makes it easy to provide the second opposing surfaces 312b and 313b, which restrict the movement of the spacer 200 (holder 200a), on case 300, thus easily realizing a configuration that improves the vibration resistance or shock resistance of the energy storage device 1.

[0073] A protrusion 231 is provided on one of the spacer 200 (holder 200a) and the case 300 (in this embodiment, the holder 200a), and recesses 312a and 313a into which the protrusion 231 is inserted are provided on the other (in this embodiment, the case 300). The opposing surfaces of the protrusion 231 and the recesses 312a and 313a are designated as the first opposing surface 231a and the second opposing surfaces 312b and 313b. As a result, by inserting the protrusion 231 into the recesses 312a and 313a, the second opposing surfaces 312b and 313b can be positioned to contact the first opposing surface 231a, thus restricting the movement of the spacer 200 (holder 200a) within the case 300 with a simple configuration. Therefore, a configuration that improves the vibration resistance or shock resistance of the energy storage device 1 can be easily realized.

[0074] Since each of the multiple spacers 200 (holders 200a) has a first opposing surface 231a, the second opposing surfaces 312b and 313b of the case 300 come into contact with the multiple first opposing surfaces 231a of the multiple spacers 200 (holders 200a), thereby restricting the movement of the spacers 200 (holders 200a). This restricts the movement of the multiple spacers 200 (holders 200a) within the case 300, thereby further improving the vibration resistance or shock resistance of the energy storage device 1.

[0075] The second opposing surfaces 312b and 313b of the case 300 are formed continuously over the multiple first opposing surfaces 231a of the multiple spacers 200 (holders 200a). This eliminates the need to form multiple second opposing surfaces 312b and 313b on the case 300, allowing for the formation of the second opposing surfaces 312b and 313b on the case 300 with a simple configuration. Therefore, the movement of the multiple spacers 200 (holders 200a) within the case 300 can be restricted with a simple configuration, making it easy to realize a configuration that improves the vibration resistance or shock resistance of the energy storage device 1.

[0076] At least one of the spacer 200 (holder 200a) and the case 300 (in this embodiment, the holder 200a) has a deformable portion 232. Therefore, when inserting the spacer 200 (holder 200a) into the case 300, the deformable portion 232 can adjust the distance in the third direction (X-axis direction) between the first opposing surface 231a and the second opposing surfaces 312b, 313b. This prevents the spacer 200 (holder 200a) from hitting the case 300 with the portion having the first opposing surface 231a, or from hitting the spacer 200 (holder 200a) with the portions having the second opposing surfaces 312b, 313b, making insertion difficult. Therefore, the spacer 200 (holder 200a) can be easily inserted into the case 300, and the second opposing surfaces 312b and 313b can be easily positioned to contact the first opposing surface 231a, thus easily realizing a configuration that improves the vibration resistance or shock resistance of the energy storage device 1.

[0077] [3 Explanation of variations] Although an embodiment of the present invention, the energy storage device 1, has been described above, the present invention is not limited to the above embodiment. The embodiments disclosed herein are illustrative in all respects, and the scope of the present invention includes all modifications in the sense and scope equivalent to the claims.

[0078] (Variation 1) In the above embodiment, the position of the movement limiting portion 230 provided on the spacer 200 (holder 200a) is not particularly limited. The movement limiting portion 230 does not have to be placed at the Z-axis positive end (second holder wall portion 223) of the holder 200a, but may be placed at the Z-axis central part of the holder 200a, or at the Z-axis negative end (second holder wall portion 224, etc.). The movement limiting portion 230 may be placed at the Y-axis central position of the spacer 200 (holder 201), as shown in Figure 7. Figure 7 is a perspective view showing the configuration of the spacer 200 (holder 201) according to Modification 1 of this embodiment. Figure 7 is a diagram corresponding to Figure 4.

[0079] As shown in Figure 7, in this modified example, the holder 201 has a movement limiting portion 230 positioned at the center of the second holder wall portion 223 in the Y-axis direction. Specifically, the movement limiting portion 230 is positioned within the width range of the holder body 210 in the Y-axis direction. As a result, the movement limiting portion 230 is positioned between the two energy storage elements 100 that sandwich the holder 201 in the Y-axis direction. In other words, the energy storage device 1 is equipped with two energy storage elements 100 that sandwich the spacer 200 (holder 201) in the Y-axis direction (first direction), and the first opposing surface 231a of the protrusion 231 of the movement limiting portion 230 is positioned between the two energy storage elements 100 in the Y-axis direction (first direction). The other configurations of this modified example are the same as in the above embodiment, so a detailed explanation is omitted.

[0080] As described above, the energy storage device 1 according to this modified example can achieve the same effects as the above embodiment. In particular, when inserting the spacer 200 (holder 201) into the case 300, or when the energy storage device 1 is subjected to external vibration or shock, the portion of the spacer 200 (holder 201) on which the first opposing surface 231a is provided may move inward into the case 300. That is, in the holder 201, the movement limiting portion 230 may move toward the holder body 210 in the X-axis direction. For this reason, the first opposing surface 231a (movement limiting portion 230) of the spacer 200 (holder 201) is positioned between the two energy storage elements 100 that sandwich the holder 201. This prevents the portion of the spacer 200 (holder 201) on which the first opposing surface 231a is provided (movement limiting portion 230) from contacting (compressing) the energy storage elements 100 even when it moves inward into the case 300. Therefore, it is possible to improve the vibration resistance or shock resistance of the energy storage device 1 while suppressing the impact on the energy storage element 100.

[0081] (Modification 2) In the above embodiment, the shape of the movement limiting portion 230 provided on the spacer 200 (holder 200a) is not particularly limited and can be formed in various shapes. Figure 8 is a perspective view showing the configuration of the spacer 200 (holder 202) according to a modified example 2 of this embodiment. Figure 8 corresponds to Figure 4.

[0082] As shown in Figure 8, the holder 202 in this modified example has a movement limiting portion 240 instead of the movement limiting portion 230 that the holder 200a in the above embodiment has. The other configurations of this modified example are the same as in the above embodiment, so a detailed explanation is omitted.

[0083] The movement-restricting portion 240 has a protrusion 241 and a deformable portion 242. The protrusion 241 is a projection (claw) that protrudes in the X-axis direction from the Z-axis negative end of the deformable portion 242. Specifically, the movement-restricting portion 240 provided on the second holder wall portion 223 in the X-axis positive direction has a protrusion 241 that protrudes in the X-axis positive direction from the X-axis positive and Z-axis negative end of the deformable portion 242. The same applies to the movement-restricting portion 240 provided on the second holder wall portion 223 in the X-axis negative direction. Each protrusion 241 has a first opposing surface 241a on the Z-axis positive direction surface, which is a plane (flat surface) parallel to the XY plane. The first opposing surface 241a is a surface that can face and contact the second opposing surface 312b or 313b of the case 300 in an orientation facing the Z-axis positive direction (one side of the second direction), similar to the first opposing surface 231a in the above embodiment.

[0084] The deformable portion 242, similar to the deformable portion 232 in the above embodiment, is a portion that deforms to make the first opposing surface 241a movable in the X-axis direction (third direction). The deformable portion 242 is a plate-shaped portion (spring) that protrudes in the X-axis direction from the Z-axis positive edge of the through hole 223a of the second holder wall portion 223, curves in the Z-axis positive direction, and further curves in the Z-axis negative direction. The deformation of the deformable portion 242 makes the convex portion 241 (first opposing surface 241a) movable in the X-axis direction. When the deformable portion 242 deforms so that the first opposing surface 241a is movable relative to the second opposing surface 312b or 313b in the X-axis direction (third direction), the first opposing surface 241a is positioned to face the second opposing surface 312b or 313b. As a result, the second opposing surface 312b or 313b contacts the first opposing surface 241a, restricting the movement of the spacer 200 (holder 202) in the Z-axis positive direction (one side of the second direction).

[0085] As described above, the energy storage device 1 according to this modified example can achieve the same effects as the embodiment described above. In particular, in this modified example, the deformable portion 242 has a curved spring shape and protrudes in the X-axis direction, so the spring's repulsive force presses the convex portion 241 toward the case wall portion 312 or 313 in the X-axis direction. This also restricts the movement of the spacer 200 (holder 202) in the X-axis direction.

[0086] (Other variations) In the above embodiment, the second opposing surface 312b or 313b of the case 300 that contacts the first opposing surface 231a of the spacer 200 (holder 200a) is provided in a recess 312a or 313a formed in the case wall portion 312 or 313 of the case body 310, but it is not limited to this. The second opposing surface 312b or 313b may be provided in a recess formed in the side wall of the lid 320. The surface of the lid 320 in the negative Z-axis direction may also be the second opposing surface 312b or 313b. In other words, by sandwiching the convex portion 231 of the holder 200a between the case body 310 and the lid 320, the surface of the lid 320 in the negative Z-axis direction may be brought into contact with the first opposing surface 231a of the convex portion 231, thereby restricting the movement of the holder 200a in the positive Z-axis direction. The second opposing surface 312b or 313b may be provided at any other position on the case 300 besides those described above. Multiple sets of first opposing surfaces 231a and second opposing surfaces 312b (or multiple sets of first opposing surfaces 231a and second opposing surfaces 313b) may be provided for a single holder 200a.

[0087] In the above embodiment, the movement-restricting portion 230 of the spacer 200 (holder 200a) has a protrusion 231, and the case 300 has a recess 312a or 313a into which the protrusion 231 is inserted, but the embodiment is not limited to this. The case 300 may have a through hole (a through hole penetrating the case wall portion 312 or 313 in the X-axis direction) into which the protrusion 231 is inserted, instead of a recess 312a or 313a. Alternatively, the case 300 may have a protrusion, and the spacer 200 (holder 200a) may have a recess or through hole into which the protrusion is inserted. In other words, it is sufficient if one of the spacer 200 (holder 200a) or the case 300 has a protrusion, and the other has a recess or through hole into which the protrusion is inserted. In this case, the first opposing surface 231a and the second opposing surfaces 312b, 313b may be two surfaces that face each other in the Z-axis direction (second direction) of the protrusion and the recess or through hole. In this case, the protrusion may be a portion of the holder 200a and case 300 in which the male thread of a bolt is formed, and the recess or through hole may be a portion of the other of the holder 200a and case 300 in which the female thread that connects to the bolt is formed. Alternatively, the first opposing surface 231a and the second opposing surfaces 312b, 313b may be two surfaces of the protrusion and the protrusion, or surfaces provided on a stepped portion, or surfaces provided on an end face, or any other surfaces of the holder 200a and case 300. These can also achieve the same effects as the above embodiment.

[0088] In the above embodiment, the second opposing surfaces 312b and 313b of the case 300 are assumed to be continuous surfaces extending across the multiple first opposing surfaces 231a of the multiple spacers 200 (multiple holders 200a), but the embodiment is not limited to this. The second opposing surfaces 312b and 313b may be divided and provided intermittently for each of the several first opposing surfaces 231a, or they may be provided for each first opposing surface 231a. In this case, the recess 312a or 313a is divided and intermittently provided, and the protrusion 231 of the holder 200a is inserted into each of the recesses, thereby restricting the movement of the holder 200a in the Y-axis direction as well.

[0089] In the above embodiment, the movement-restricting portion 230 of the spacer 200 (holder 200a) is assumed to have a deformable portion 232. However, the case 300 may also have a deformable portion that deforms the second opposing surfaces 312b and 313b to be movable relative to the first opposing surface 231a in the X-axis direction (third direction). In other words, it is sufficient that at least one of the spacer 200 (holder 200a) and the case 300 has a deformable portion that deforms at least one of the first opposing surface 231a and the second opposing surfaces 312b and 313b to be movable relative to the other in the X-axis direction (third direction). This also produces the same effects as the above embodiment. However, if the case 300 is a metal case, it is preferable that the spacer 200 (holder 200a) has a deformable portion 232 because it is difficult to deform. Alternatively, neither the spacer 200 (holder 200a) nor the case 300 has a deformable portion.

[0090] In the above embodiment, the length of the protrusion 231 and the first opposing surface 231a in the X-axis direction was described the same for any spacer 200 (holder 200a) arranged in the Y-axis direction, but this is not essential. Depending on the formation accuracy of the case 300 in the Y-axis direction, even if the length of the recesses 312a, 313a and the second opposing surfaces 312b, 313b in the X-axis direction changes depending on any position in the Y-axis direction, a spacer 200 (holder 200a) with a longer or shorter length of the protrusion 231 and the first opposing surface 231a in the X-axis direction may be used depending on any position in the Y-axis direction.

[0091] In the above embodiment, the movement limiting sections 230 were described as being provided on the second holder wall sections 223 located in the positive Z-axis direction, but this is not essential. The movement limiting sections 230 may also be provided on the second holder wall sections 224 located in the negative Z-axis direction, or they may be provided on both the second holder wall sections 223 and 224, resulting in a total of four movement limiting sections 230 on one spacer 200 (holder 200a).

[0092] In the above embodiment, two energy storage units 10 arranged in the X-axis direction are housed inside the case 300. However, three or more energy storage units 10 arranged in the X-axis direction may be housed, or only one energy storage unit 10 may be housed. If only one energy storage unit 10 is housed inside the case 300, the case 300 will have a pair of case walls 312 without a case wall 313. Multiple energy storage units 10 arranged in the Y-axis direction may be housed inside the case 300. In these cases as well, it is sufficient that the spacer 200 (holder 200a) and the case 300 are provided with a first opposing surface 231a and second opposing surfaces 312b, 313b.

[0093] In the above embodiment, the case body 310 has sufficient height in the Z-axis direction to house the energy storage unit 10, and is configured so that the energy storage unit 10 is not exposed when viewed from the XY plane, but this is not essential. The case body 310 may have a height of about two-thirds or half of the energy storage unit 10 in the Z-axis direction to house the portion of the energy storage unit 10 in the negative Z-axis direction, and leave the portion of the energy storage unit 10 in the positive Z-axis direction exposed. In this case, the lid 320 may have a height of about one-third or half of the energy storage unit 10 in the Z-axis direction to house the portion of the energy storage unit 10 in the positive Z-axis direction.

[0094] In the above embodiment, all spacers 200 (all holders 200a) are assumed to have the above configuration, but it is not necessary for any of the spacers 200 (holders 200a) to have the above configuration. In the above embodiment, both sides of the spacer 200 (holder 200a) in the X-axis direction are assumed to have the above configuration, but it is not necessary for one side in the X-axis direction to have the above configuration.

[0095] In the above embodiment, the spacer 200 (holder 200a) is provided with a pair of first holder wall portions 221 and 222 and a pair of second holder wall portions 223 and a pair of second holder wall portions 224, but it is not limited to having all of these wall portions. The spacer 200 (holder 200a) may be a holder that holds the energy storage element 100 by having at least one of these wall portions, or it may be a plate-shaped or the like spacer that does not have any wall portions (and does not hold the energy storage element 100).

[0096] In the above embodiment, the spacer 200 having the above configuration whose movement is restricted by the case 300 is defined as a holder 200a, but the spacer 200 may also be a holder 200b or a holder 200c. In other words, any of the multiple spacers 200 may have the same configuration as the holder 200a.

[0097] In the above embodiment, the spacers 200 (holders 200a, 200b, and 200c) are arranged alternately in the Y-axis direction with respect to the energy storage element 100, but a configuration in which none of the spacers 200 are arranged is also possible. A configuration in which only one spacer 200 (holder 200a, 200b, or 200c) is arranged is also possible.

[0098] In the above embodiment, the case 300 is assumed to have a case body 310 and a lid 320, but it is not necessary to have a lid 320.

[0099] In the above embodiment, the energy storage unit 10 may include restraining members (end plates, side plates, etc.) that restrain a plurality of energy storage elements 100 and spacers 200.

[0100] The present invention also includes forms constructed by arbitrarily combining the components of the above embodiments and their variations. [Industrial applicability]

[0101] This invention can be applied to energy storage devices equipped with energy storage elements such as lithium-ion secondary batteries. [Explanation of symbols]

[0102] 1. Energy storage device 10 Energy storage units 100 energy storage elements 110 Container 111 Long side 112 short side 113 Bottom 140 Electrode terminal 200 Spacer 200a, 200b, 200c, 201, 202 holders 210 Holder body 220 Holder wall 221, 222 First holder wall 223, 224 Second holder wall 223a Through hole 230, 240 Movement restriction section 231, 241 Convex part 231a, 241a First facing surface 232, 242 Deformed parts 300 cases 310 Case Body 310a aperture 311 Bottom wall 312, 313, 314 Case wall section 312a, 313a recess 312b, 313b Second facing surface 320 Lid

Claims

1. A power storage device comprising: a case having energy storage elements and spacers arranged in a first direction, and a case body having an opening formed on one side in a second direction perpendicular to the first direction, and housing the energy storage elements and spacers, The spacer has a first opposing surface that faces the case in a position facing one side of the second direction, The case has a second opposing surface that faces the first opposing surface in a orientation that faces the other side of the second direction, The second opposing surface, by contacting the first opposing surface, restricts the movement of the spacer to one side in the second direction. The spacer and the case each have a portion extending in the second direction and a protrusion provided at the tip of the portion in the second direction, The other of the spacer and the case has a recess or through hole into which the protrusion is inserted. The first opposing surface and the second opposing surface are two surfaces that face each other in the second direction, formed by the convex portion and the concave portion or the through hole. Energy storage device.

2. A power storage device comprising: a case having energy storage elements and spacers arranged in a first direction, and a case body having an opening formed on one side in a second direction perpendicular to the first direction, and housing the energy storage elements and spacers, The spacer has a first opposing surface that faces the case in a position facing one side of the second direction, The case has a second opposing surface that faces the first opposing surface in a orientation that faces the other side of the second direction, The second opposing surface, by contacting the first opposing surface, restricts the movement of the spacer to one side in the second direction. At least one of the spacer and the case has a deformable portion that deforms at least one of the first opposing surface and the second opposing surface so as to be movable relative to the other in a third direction perpendicular to the first and second directions. Energy storage device.

3. The case body has a bottom wall positioned to face the second direction, and side walls positioned to face a third direction perpendicular to the first and second directions. The second opposing surface is provided on the side wall. The energy storage device according to claim 1 or 2.

4. The energy storage device comprises a plurality of spacers arranged in the first direction together with the energy storage element, Each of the aforementioned plurality of spacers has the first opposing surface. The energy storage device according to any one of claims 1 to 3.

5. The second opposing surface is a surface that is continuous with the plurality of first opposing surfaces that the plurality of spacers have. The energy storage device according to claim 4.

6. The energy storage device comprises two energy storage elements that sandwich the spacer in the first direction, The first opposing surface is positioned between the two energy storage elements in the first direction. The energy storage device according to any one of claims 1 to 5.

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