Power storage device

Abstract

A power storage device comprising a power storage element, an insulating member that is disposed along the power storage element and supports the power storage element, and a side member that is disposed along an outer surface of the insulating member, wherein: the insulating member comprises a support part that supports the power storage element; the support part comprises a first support part that supports a first side surface of the power storage element and extends toward one side in a first direction along the first side surface, a connection part provided to the end section of the first support part on the one side thereof in the first direction, and a second support part which is connected to the connection part and extends toward the other side in the first direction; the side member comprises a supported part disposed between the first support part and the second support part; one part among the second support part and the supported part comprises a first protruding part that protrudes toward the other of said parts; one part among the second support part and the supported part comprises a second protruding part that protrudes toward the other of said parts; and the second protruding part is disposed between the first protruding part and the connection part in the first direction.

Description

Power storage device

[0001] The present invention relates to a power storage device.

[0002] Patent Document 1 discloses a power storage stack including a plurality of power storage cells, a plurality of cell holders, and a plurality of bus bars. The cell holder holds a power storage cell having a bottom surface. The cell holder includes an upper plate portion and a bottom plate portion that face each other in the vertical direction with the power storage cell disposed therebetween, a main wall portion, and a pair of lip portions provided at both ends of the bottom plate portion in the width direction of the cell holder. The pair of lip portions is provided so as to be elastically biased toward the upper plate portion while contacting the bottom surface of the power storage cell.

[0003] Japanese Patent Application Laid-Open No. 2023-69845

[0004] In the above conventional power storage stack, the cell holder elastically biases the power storage cell toward the upper plate portion by the pair of lip portions, so that the power storage cell abuts against the upper plate portion. In this state, for example, when the power storage cell tries to move downward due to vibration or impact, the pair of lip portions is deformed so as to bend downward. In this case, the stress concentrated on the root portions of the pair of lip portions tends to increase, and as a result, the pair of lip portions may be damaged.

[0005] The present invention has been made by the inventors of the present application newly paying attention to the above problems, and an object thereof is to provide a power storage device with improved reliability.

[0006] A power storage device according to one aspect of the present invention comprises a power storage element, an insulating member arranged along the power storage element and supporting the power storage element, and a side member arranged along the outer surface of the insulating member, wherein the insulating member includes a support portion for supporting the power storage element, the support portion is a first support portion that supports the first side surface of the power storage element and includes a first support portion extending to one side in a first direction along the first side surface, a connecting portion provided at the end of the first support portion on the one side in the first direction, and a second support portion connected to the connecting portion and extending to the other side in the first direction, the side member includes a supported portion arranged between the first support portion and the second support portion, one of the second support portion and the supported portion includes a first protruding portion projecting toward the other, one of the second support portion and the supported portion includes a second protruding portion projecting toward the other, and the second protruding portion is arranged between the first protruding portion and the connecting portion in the first direction.

[0007] According to the present invention, an energy storage device with improved reliability can be provided.

[0008] Figure 1 is a perspective view showing the external appearance of the energy storage device according to the embodiment. Figure 2 is an exploded perspective view of the energy storage device according to the embodiment. Figure 3 is a first perspective view of the energy storage element and insulating member according to the embodiment. Figure 4 is a second perspective view of the energy storage element and insulating member according to the embodiment. Figure 5 is a first cross-sectional view showing the configuration of the support part and its surroundings according to the embodiment. Figure 6 is a second cross-sectional view showing the configuration of the support part and its surroundings according to the embodiment. Figure 7 is a third cross-sectional view showing the configuration of the support part and its surroundings according to the embodiment. Figure 8 is a cross-sectional view showing the configuration of the support part and its surroundings according to a modified example of the embodiment.

[0009] (1) An energy storage device according to one aspect of the present invention comprises an energy storage element, an insulating member arranged along the energy storage element and supporting the energy storage element, and a side member arranged along the outer surface of the insulating member, wherein the insulating member includes a support portion for supporting the energy storage element, the support portion is a first support portion that supports the first side surface of the energy storage element and comprises a first support portion extending to one side in a first direction along the first side surface, a connecting portion provided at the end of the first support portion on the one side in the first direction, and a second support portion connected to the connecting portion and extending to the other side in the first direction, the side member includes a supported portion arranged between the first support portion and the second support portion, one of the second support portion and the supported portion includes a first protruding portion projecting toward the other, one of the second support portion and the supported portion includes a second protruding portion projecting toward the other, and the second protruding portion is arranged between the first protruding portion and the connecting portion in the first direction.

[0010] According to one aspect of the present invention, the supported portion of the side member is positioned between the first and second support portions of the support portion of the insulating member. This restricts the movement of the insulating member and the energy storage element by the side member. Furthermore, one of the second support portion and the supported portion has a second projection that protrudes toward the other, located closer to the connection portion than the first projection. Therefore, when the energy storage element attempts to move away from the supported portion due to shock or vibration, the second projection contacts the other, preventing the support portion from deforming and opening. As a result, stress concentration in the support portion is alleviated. This suppresses damage to the insulating member, etc. Thus, according to one aspect of the present invention, the movement of the energy storage element can be restricted by the insulating member, and the resistance of the insulating member to vibration or shock is improved. Therefore, the energy storage device according to one aspect of the present invention is an energy storage device with improved reliability.

[0011] (2) In the energy storage device described in (1) above, the first protrusion and the second protrusion may be provided on the second support.

[0012] According to the energy storage device described in (2) above, the second support portion is provided with a first protrusion that primarily serves to restrict the movement of the insulating member under normal conditions, and a second protrusion that primarily serves to suppress large deformation of the support portion. In other words, since the second support portion, which is a single part, has at least two functions, the reliability of the energy storage device is improved with a simple configuration.

[0013] (3) In the energy storage device described in (1) or (2) above, the insulating member may include a first insulating member and a second insulating member arranged on one side and the other side of the energy storage element in a second direction intersecting the first direction, the side member may be arranged along the outer surfaces of the first insulating member and the second insulating member, and the supported portion may be arranged between the first support portion and the second support portion provided by the support portion of the first insulating member and the second insulating member.

[0014] According to the energy storage device described in (3) above, the side member can collectively restrict the movement of the first insulating member and the second insulating member. Therefore, it is easy to maintain the energy storage element in a state where its movement is restricted by the first insulating member and the second insulating member.

[0015] (4) In the energy storage device described in any one of (1) to (3) above, when viewed from a third direction which is the direction in which the first side surface faces, the energy storage element may have an exposed portion on one side of the support portion in the first direction in which a part of the first side surface is exposed.

[0016] According to the energy storage device described in (4) above, the support portion has an exposed portion on a part of the first side surface that is supported by the support portion whose movement in a third direction is restricted by the side member. Therefore, for example, temperature control of the energy storage element using the exposed portion is easy. This contributes to improving the reliability of the energy storage device.

[0017] (5) In the energy storage device described in any one of (1) to (4) above, the second support portion may be provided with an inclined portion that forms an inclined surface on the other side in the first direction from the first protrusion, in which the inclined surface moves away from the first support portion as it moves toward the other side.

[0018] According to the energy storage device described in (5) above, the supported part can be smoothly inserted between the first support part and the second support part. As a result, problems such as the supported part colliding with a part of the second support part in the insertion direction when inserting the supported part between the first support part and the second support part are less likely to occur. In other words, defects such as damage to insulating members or side members during the manufacturing of the energy storage device are less likely to occur.

[0019] (6) In the energy storage device described in any one of (1) to (5) above, a gap may be formed between the second protruding portion and the other of the second support portion and the supported portion.

[0020] According to the energy storage device described in (6) above, the second protruding part is less likely to get in the way when inserting the supported part between the first and second support parts. Therefore, the work of inserting the supported part between the first and second support parts can be performed efficiently.

[0021] The following description of an energy storage device according to embodiments and modifications thereof of the present invention will be given with reference to the drawings. The embodiments and modifications described below are general or specific examples. The numerical values, shapes, materials, components, arrangement and connection configurations of components, manufacturing processes, and manufacturing process sequences shown in the following embodiments and modifications are examples only and are not intended to limit the present invention. Furthermore, dimensions and other specifications in the drawings are not strictly illustrated. Additionally, the same or similar components are denoted by the same reference numerals in each drawing.

[0022] In the following description and drawings, the direction in which a pair of terminals are aligned in one energy storage element, the direction in which a pair of short sides of one energy storage element are opposed to each other, or the direction in which a pair of side members are aligned is defined as the X-axis direction. The direction in which multiple energy storage elements are aligned, the direction in which multiple spacers are aligned, the direction in which a pair of end members are aligned, the direction in which a pair of long sides of one energy storage element are opposed to each other, or the thickness direction of an energy storage element or end member is defined as the Y-axis direction. The direction in which the container body and the lid plate of an energy storage element are aligned, 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.

[0023] 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 referred to as the X-axis direction, it refers to either the X-axis positive direction or the X-axis negative direction, or either direction. The same applies to the Y-axis and Z-axis directions. In the following, the X-axis direction may be referred to as the first direction, the Y-axis direction as the second direction, and the Z-axis direction as 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, when two directions are orthogonal, it means not only that the two directions are perfectly orthogonal, but also that they are substantially orthogonal, i.e., that they include a difference of, for example, a few percent. In the following explanation, when "insulation" is used, it means "electrical insulation". The volume resistivity of an insulating material is 1 × 10⁻⁶ ６ Preferably Ωm or more, 1 × 10 ７ Ωm or greater is more preferable, 1 × 10 １０ A value of Ωm or greater is even more preferable.

[0024] (Embodiment) [1. General Description of the Energy Storage Device] First, a general description of the energy storage device 10 according to this embodiment will be given using Figures 1 and 2. Figure 1 is a perspective view showing the external appearance of the energy storage device 10 according to this embodiment. Figure 2 is an exploded perspective view of the energy storage device 10 according to this embodiment.

[0025] The energy storage device 10 is a device that can charge electricity from an external source and discharge electricity to an external source. The energy storage device 10 is a battery module (battery pack) used for power storage or power supply purposes. Specifically, the energy storage device 10 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, automated guided vehicles (AGVs), 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 10 can also be used as a stationary battery for household or commercial use.

[0026] As shown in Figures 1 and 2, the energy storage device 10 comprises an energy storage element array 30 including a plurality of energy storage elements 20, a pair of end members 400, and a pair of side members 500. In this embodiment, the pair of end members 400 and the pair of side members 500 constitute a restraining member 600 that restrains the energy storage element array 30 in the Y-axis direction.

[0027] The energy storage element array 30 includes insulating members 100 arranged along the energy storage elements 20. The insulating members 100 are positioned next to the energy storage elements 20 in the Y-axis direction. More specifically, in this embodiment, the insulating member 100 includes insulating members 100B positioned at both ends in the direction of arrangement of the plurality of energy storage elements 20 (the Y-axis direction in this embodiment), and insulating members 100A positioned between two adjacent energy storage elements 20. In other words, in this embodiment, the insulating member 100 is composed of a pair of insulating members 100B and a plurality of insulating members 100A. The direction in which the energy storage element 20 faces the main body (insulating main body 101, see Figures 3 and 4 described later) of the insulating member 100A or 100B adjacent to the energy storage element 20 is an example of a second direction. In this embodiment, the second direction coincides with the direction of arrangement of the plurality of energy storage elements 20 and the Y-axis direction.

[0028] The energy storage device 10 also includes busbars that connect the energy storage elements 20 in series or parallel, but their illustration and description are omitted. In addition to the above components, the energy storage device 10 may also include an insulating (resin) busbar frame for positioning the busbars, an outer casing for housing the above components, external terminals connected to external busbars, etc., and electrical equipment such as a circuit board, fuses, relays, and connectors for monitoring or controlling the charging and discharging states of the energy storage elements 20.

[0029] The energy storage element 20 is a secondary battery (single cell), more specifically, a non-aqueous electrolyte secondary battery such as a lithium-ion secondary battery. The energy storage element 20 has a flattened rectangular parallelepiped shape (gonal). A rectangular parallelepiped, as used here, is a hexahedron in which all faces are rectangles or squares. In this embodiment, eight energy storage elements 20 are arranged in the Y-axis direction. The size, shape, and number of energy storage elements 20 included in the energy storage element array 30 are not limited. The number of energy storage elements 20 included in the energy storage element array 30 should be one or more. The energy storage element 20 may be a secondary battery other than a non-aqueous electrolyte secondary battery, or it may be a capacitor. The energy storage element 20 may be a primary battery. The energy storage element 20 may be a pouch-type energy storage element. The energy storage element 20 may be a battery using a solid electrolyte.

[0030] The insulating member 100 includes a support portion 120 that supports the first side surface 21a of the energy storage element 20. In this embodiment, each of the insulating members 100A and 100B included in the insulating member 100 is provided with a support portion 120. The configuration of the support portion 120 and its surrounding area will be described later with reference to Figures 3 to 7. The first side surface 21a supported by the support portion 120 may also be described as the end portion of the energy storage element 20 facing the support portion 120 (for example, referred to as the "side portion"). In cases where the energy storage element 20 is a pouch-type energy storage element or a cylindrical energy storage element, the portion of the energy storage element 20 supported by the support portion 120 does not need to be flat, but may be a curved surface or a bent surface, etc.

[0031] The insulating members 100A and 100B are positioned adjacent to the energy storage element 20 and support the energy storage element 20. More specifically, insulating member 100A is positioned between two adjacent energy storage elements 20 in the Y-axis direction and is an inter-cell spacer that insulates one of these two energy storage elements 20 from the other. Insulating member 100B is positioned between an end energy storage element 20 in the energy storage element row 30 and an end member 400 and is an end spacer that insulates the energy storage element 20 from the end member 400. In this embodiment, each of the insulating members 100A and 100B also functions as a cell holder that holds the energy storage element 20.

[0032] In this embodiment, the energy storage element array 30 has seven insulating members 100A and a pair (two) insulating members 100B arranged to correspond to eight energy storage elements 20. The number of insulating members 100A and 100B can be appropriately changed depending on the number of energy storage elements 20 (one or more) provided in the energy storage device 10. The insulating members 100A and 100B are 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 coated metals, or from insulating materials such as aggregates of mica pieces.

[0033] The restraining member 600 compresses (restrains) the energy storage element array 30 in the arrangement direction (Y-axis direction) by the end member 400 and the side member 500. The end member 400 and the side member 500 are made of metal such as steel or stainless steel for the sake of ensuring strength, but their material is not particularly limited. The end member 400 and the side member 500 may be made of, for example, a highly insulating material. The surfaces of the metal end member 400 and the side member 500 may be treated with an insulating treatment such as a resin coating.

[0034] The end members 400 are positioned on both sides of the energy storage element array 30 in the Y-axis direction and support the energy storage element array 30 by sandwiching it from both sides in the arrangement direction (Y-axis direction). In this embodiment, the end members 400 are block-shaped members. However, for example, a plate-shaped member (for example, called an "end plate") with its thickness direction oriented in the Y-axis direction may be used as the end members 400. The end members 400 have fixing holes 430 that penetrate in the Z-axis direction, and fixing members 710, such as long bolts, which are positioned to penetrate the fixing holes 430, are connected to screw holes 810 provided in, for example, the installation member 800. In this way, the end members 400 are fixed to the installation member 800. There are no particular limitations on the installation member 800, but examples include a shelf of a rack that houses the energy storage device 10, a floor wall of a housing that houses one or more energy storage devices 10, or a metal member inside a vehicle on which the energy storage device 10 is mounted. In this embodiment, each of the pair of end members 400 is fixed to the installation member 800 by two fixing members 710.

[0035] The side members 500 are plate-shaped and elongated members positioned laterally to the energy storage element row 30 in the X-axis direction, which is perpendicular to the Y-axis direction, which is the arrangement direction (second direction). Specifically, the side members 500 are positioned in the X-axis positive direction and the X-axis negative direction of the energy storage element row 30. An insulating sheet made of an insulating material such as resin may be placed between each of the pair of side members 500 and the energy storage element row 30. The side members 500 are attached to a pair of end members 400 at both ends in the Y-axis direction, and the energy storage element row 30 is constrained by connecting the pair of end members 400. The X-axis direction is an example of the first direction.

[0036] In this embodiment, the side member 500 comprises a side main body portion 501 facing the energy storage element row 30 in the X-axis direction, and a supported portion 510 supported by the support portion 120 of the insulating member 100 in at least the Z-axis direction. The Z-axis direction is an example of a third direction.

[0037] The side member 500 is connected to the end member 400 by two bolts 750 aligned in the Z-axis direction. The end member 400 is provided with through holes 450 through which the bolts 750 pass. The connection of the side member 500 to the end member 400 is not limited to fixing with bolts 750, but may also be made by welding or riveting. The number of connection points between one side member 500 and one end member 400 does not have to be two, but may be one or three or more. For example, one side member 500 and one end member 400 may be connected by three or more bolts 750.

[0038] Thus, the side member 500 is connected to the end member 400, and the end member 400 is fixed to the mounting member 800 as described above. As a result, the side member 500 is fixed to the mounting member 800 via the end member 400. The side member 500, whose position relative to the mounting member 800 is fixed, can suppress movement (shift) of the energy storage element 20 in the Z-axis direction via the insulating member 100.

[0039] The energy storage device 10 according to this embodiment does not need to include a restraining member 600. Specifically, the energy storage device 10 only needs to include at least one side member 500 from a pair of end members 400 and a pair of side members 500. In this case, the side member 500 may be fixed to the installation member 800 directly or via other members.

[0040] [2. Description of the Energy Storage Element 20 and Insulating Member 100A] Figure 3 is a first perspective view of the energy storage element 20 and insulating member 100A according to the embodiment. Figure 4 is a second perspective view of the energy storage element 20 and insulating member 100A according to the embodiment. Figures 3 and 4 focus on one energy storage element 20, and show the energy storage element 20 and two insulating members 100A that support the energy storage element 20. In Figures 3 to 8 and the following description, when distinguishing between these two insulating members 100A, the insulating member 100A positioned in the negative Y-axis direction of the energy storage element 20 will be referred to as the first insulating member 100Aa, and the insulating member 100A positioned in the positive Y-axis direction of the energy storage element 20 will be referred to as the second insulating member 100Ab. In this embodiment, the first insulating member 100Aa and the second insulating member 100Ab have the same configuration. Therefore, the explanation of the configuration of the first insulating member 100Aa also applies to the second insulating member 100Ab.

[0041] As shown in Figures 3 and 4, the energy storage element 20 comprises a container 21 and a pair of terminals 22 (positive and negative electrodes). Inside the container 21 are electrode bodies, a pair of current collectors (positive and negative electrodes), and an electrolyte (non-aqueous electrolyte), 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 20, and various types can be selected.

[0042] In addition to the above-mentioned components, the energy storage element 20 may also have spacers or the like positioned to the side or below the electrode body. The container 21 is a rectangular parallelepiped (box-shaped) case. The container 21 has a container body 24 and a lid plate 25 that closes the opening of the container body 24. After the electrode body and the like are housed inside the container body 24, the container body 24 and the lid plate 25 are joined by welding or the like to seal the inside of the container 21. The material of the container body 24 and the lid plate 25 is not particularly limited, but it is preferable that they be weldable metals such as stainless steel, aluminum, aluminum alloy, iron, or plated steel sheet.

[0043] As shown in FIG. 3, the container 21 includes a first side surface 21a in the negative Z-axis direction, a second side surface 21b in the positive Y-axis direction and the negative Y-axis direction, a third side surface 21c in the positive X-axis direction and the negative X-axis direction, and a fourth side surface 21d in the positive Z-axis direction. In the present embodiment, the first side surface 21a is the bottom surface of the container 21, a part of which is covered by the insulating member 100 and the other part is exposed from the insulating member 100. That is, the first side surface 21a includes an exposed portion 21a1 (described later using FIG. 5) that is not covered by the insulating member 100. The second side surface 21b is the long side surface of the container 21, the third side surface 21c is the short side surface of the container 21, and the fourth side surface 21d is the terminal arrangement surface of the container 21. The first side surface 21a, the second side surface 21b, and the third side surface 21c are formed by the container body 24, and the fourth side surface 21d is formed by the cover plate 25.

[0044] The first side surface 21a, which is the bottom surface of the container 21 (power storage element 20), can be described as the downward surface when the power storage element 20 is in use, or the surface facing the direction opposite to the direction (positive Z-axis direction) in which the terminals 22 of the power storage element 20 are arranged (negative Z-axis direction). When the container 21 of the power storage element 20 is composed of the container body 24 and the cover plate 25 (see FIG. 3), the first side surface 21a, which is the bottom surface of the power storage element 20, may be described as the outer surface of the wall portion of the container body 24 facing the cover plate 25.

[0045] The second side surface 21b, which is the long side surface, is arranged to face the insulating main body portion 101 of the first insulating member 100Aa or the second insulating member 100Ab in the Y-axis direction. The third side surface 21c, which is the short side surface, is adjacent to the first side surface 21a, the second side surface 21b, and the fourth side surface 21d and has a smaller area than the second side surface 21b. A pair of terminals 22 are arranged on the fourth side surface 21d. A gas discharge valve or the like for releasing the pressure when the pressure inside the container 21 rises excessively may be arranged on the fourth side surface 21d.

[0046] The terminal 22 is a terminal that is electrically connected to the electrode body via a current collector. The terminal 22 is formed of aluminum, an aluminum alloy, copper, a copper alloy, or the like. In the present embodiment, the terminal 22 has a flat surface portion to which a conductive member such as a bus bar is welded. The terminal 22 may have a shaft portion for fixing a conductive member such as a bus bar using a nut.

[0047] The electrode body includes a positive electrode plate, a negative electrode plate, and a separator, and is a power storage element (power generation element) that can store electricity. The positive electrode plate is a plate (electrode plate) in which a positive electrode active material layer is formed on the surface of a positive electrode current collector foil that is a long strip-shaped metal foil. The negative electrode plate is a plate (electrode plate) in which a negative electrode active material layer is formed on the surface of a negative electrode current collector foil that is a long strip-shaped metal foil. Aluminum or an aluminum alloy or the like is used for the positive electrode current collector foil. Copper or a copper alloy or the like is used for the negative electrode current collector foil. As the positive electrode active material and the negative electrode active material, any known material can be appropriately used as long as it can occlude and release charge transport ions. As the separator, a microporous sheet or non-woven fabric made of resin can be used. In the present embodiment, the electrode body is formed by laminating electrode plates in the Y-axis direction. The electrode body included in the power storage element 20 may be any form of electrode body, such as a wound-type electrode body formed by winding electrode plates, a stacked-type (stacked-type) electrode body formed by laminating a plurality of flat electrode plates, or a bellows-type electrode body formed by folding electrode plates in a bellows shape.

[0048] As shown in FIGS. 3 and 4, the insulating member 100A according to the present embodiment includes a support portion 120 disposed along the first side surface 21a of the power storage element 20 and an insulating main body portion 101 disposed along the second side surface 21b of the power storage element 20. That is, the support portion 120 faces the power storage element 20 in the Z-axis direction, and the insulating main body portion 101 faces the power storage element 20 in the Y-axis direction.

[0049] More specifically, the support portion 120 faces the first side surface 21a in the Z-axis direction at the X-axis end of the first side surface 21a. In this embodiment, the support portion 120 faces the X-axis positive end of the first side surface 21a and the X-axis negative end of the first side surface 21a in the Z-axis direction. In other words, the support portion 120 is provided at the Z-axis negative edge of the insulating body portion 101, and at both ends in the X-axis direction. Each of the pair of support portions 120 supports the energy storage element 20 from the Z-axis negative direction. In other words, the movement of the energy storage element 20 in the Z-axis negative direction is restricted by the pair of support portions 120.

[0050] Each of the pair of support portions 120 comprises a first support portion 121, a second support portion 125, and a connecting portion 128. The first support portion 121 supports the first side surface 21a and extends to one side in the X-axis direction along the first side surface 21a of the energy storage element 20. The connecting portion 128 is provided at the end of the first support portion 121 on that side in the X-axis direction. The second support portion 125 is connected to the connecting portion 128 and extends to the other side in the X-axis direction.

[0051] For example, the configuration of the support portion 120 in the positive X-axis direction of a pair of support portions 120 can be described as follows. The first support portion 121 extends in the negative X-axis direction, and the connecting portion 128 is provided at the end of the first support portion 121 in the negative X-axis direction. Furthermore, the second support portion 125 is connected to the connecting portion 128 and extends in the positive X-axis direction. In the support portion 120, the first support portion 121 extends in the X-axis direction, the orientation of the support portion 120 in the Z-axis direction is changed by the connecting portion 128 at the X-axis end of the first support portion 121, and the second support portion 125 extends in the X-axis direction at the Z-axis end of the connecting portion 128. The support portion 120 has a shape that is continuous with the second support portion 125 by folding back from the first support portion 121 by the connecting portion 128.

[0052] The insulating member 100A has support portions 120 (i.e., a first support portion 121, a connecting portion 128, and a second support portion 125) in the Z-axis negative direction of the insulating main body portion 101, both in the Y-axis positive direction and the Y-axis negative direction of the insulating main body portion 101. The first support portion 121, located in the Y-axis positive direction and the Y-axis negative direction of the insulating main body portion 101, is formed continuously with the Z-axis negative ends of the insulating main body portion 101 and the side wall portion 102, which will be described later. The connecting portion 128 and the second support portion 125, located in the Y-axis positive direction and the Y-axis negative direction of the insulating main body portion 101, are formed to be continuously connected from one side to the other in the Y-axis direction of the insulating main body portion 101. In other words, the connecting portion 128 and the second support portion 125 are connected on the front and back sides in the Y-axis direction of the insulating main body portion 101.

[0053] The insulating body portion 101 is positioned between two energy storage elements 20 aligned in the Y-axis direction, thereby suppressing contact between the second side surface 21b of the insulating body portion 101 located in the positive Y-axis direction and the second side surface 21b of the insulating body portion 101 located in the negative Y-axis direction.

[0054] The insulating member 100A according to this embodiment further comprises a side wall portion 102 and an upper wall portion 103. The side wall portions 102 are positioned in the positive X-axis direction and the negative X-axis direction of the insulating main body portion 101, respectively, and face the third side surface 21c (see Figure 3) of the energy storage element 20. In other words, the movement of the energy storage element 20 in the X-axis direction is restricted by the pair of side wall portions 102. The upper wall portion 103 is positioned in the positive Z-axis direction of the insulating main body portion 101 and faces the fourth side surface 21d (see Figure 3) of the energy storage element 20. In other words, the movement of the energy storage element 20 in the positive Z-axis direction is restricted by the upper wall portion 103.

[0055] Thus, in this embodiment, the energy storage element 20 is surrounded from the X-axis direction, Y-axis direction, and Z-axis direction by insulating members 100A arranged along the energy storage element 20. In other words, the insulating member 100A according to this embodiment has a structure for holding the energy storage element 20. More specifically, as shown in Figures 3 and 4, the support portion 120, the side wall portion 102, and the upper wall portion 103 extend from the insulating main body portion 101 in both the Y-axis positive direction and the Y-axis negative direction. Therefore, one insulating member 100A can hold two energy storage elements 20 arranged on both sides of the insulating main body portion 101 in the Y-axis direction. In the insulating member 100B arranged at the Y-axis end of the energy storage element row 30, the side wall portion 102 and the upper wall portion 103 extend from the insulating main body portion 101 in both the Y-axis positive direction and the Y-axis negative direction (see Figure 2). In other words, the insulating member 100B is configured to hold one energy storage element 20 facing each other in the Y-axis direction.

[0056] Each of the six energy storage elements 20 in the energy storage element row 30, excluding the energy storage elements 20 at both ends, is held by two adjacent insulating members 100A in the Y-axis direction. These six energy storage elements 20 are each fitted inside a frame shape formed by the support portion 120, side wall portion 102, and upper wall portion 103 of the insulating member 100A. The energy storage elements 20 at the ends of the energy storage element row 30 are held by insulating members 100A and 100B. These end energy storage elements 20 are each fitted inside a frame shape formed by the support portion 120, side wall portion 102, and upper wall portion 103 of the insulating members 100A and 100B.

[0057] In this embodiment, the support portion 120 of the insulating member 100A and insulating member 100B is configured such that a gap is provided between the first support portion 121 and the second support portion 125, which are aligned in the Z-axis direction, so that the supported portion 510 of the side member 500 can be inserted. The configuration of the support portion 120 and its surroundings in the energy storage device 10 according to this embodiment will be further described with reference to Figures 5 to 7.

[0058] [3. Configuration of the support portion 120 and its surroundings] Figure 5 is a first cross-sectional view showing the configuration of the support portion 120 and its surroundings according to the embodiment. In Figure 5, a cross-section of the insulating member 100 (more specifically, the first insulating member 100Aa) and the energy storage element 20 is simply shown, parallel to the XZ plane passing through the V-V line in Figure 4. Figure 6 is a second cross-sectional view showing the configuration of the support portion 120 and its surroundings according to the embodiment. In Figure 6, a cross-section is simply shown in which the supported portion 510 of the side member 500 is inserted into the support portion 120. Figure 7 is a third cross-sectional view showing the configuration of the support portion 120 and its surroundings according to the embodiment. In Figure 7, the support portion 120 is shown in cross-section when the insulating member 100 moves in the Z-axis positive direction relative to the side member 500. The positions of the cross-sections in Figures 6 and 7 correspond to the positions of the cross-sections in Figure 5.

[0059] The insulating member 100 according to this embodiment supports the energy storage element 20 and includes a support portion 120 that can contact the side member 500 in the Z-axis direction. More specifically, as shown in Figures 2 to 4, each of the multiple insulating members 100A and 100B included in the insulating member 100 is provided with a pair of support portions 120. Since these support portions 120 have a common configuration, the following description will focus on the support portion 120 in the X-axis positive direction of the pair of support portions 120 provided by the insulating member 100A, as shown in Figures 5 to 7, and will explain its configuration and other details.

[0060] As shown in Figures 5 to 7, the support portion 120 comprises a first support portion 121 and a second support portion 125 that are spaced apart and facing each other in the Z-axis direction, and a connecting portion 128 that connects the first support portion 121 and the second support portion 125. The first support portion 121 is a plate-shaped portion that is connected to the side wall portion 102 of the insulating member 100A in the X-axis positive direction and extends in the X-axis negative direction. The first support portion 121 can support the energy storage element 20 by facing the first side surface 21a of the energy storage element 20 in the Z-axis direction and having the Z-axis positive surface of the first support portion 121 contact the first side surface 21a. In other words, the first support portion 121 restricts the movement of the energy storage element 20 in the Z-axis negative direction. A connecting portion 128 is provided at the X-axis negative end of the first support portion 121, which bends from that end and extends in the Z-axis negative direction. A second support portion 125 is connected to the Z-axis negative end of the connecting portion 128. The second support portion 125 is a plate-shaped part that bends from the Z-axis negative end of the connecting portion 128 and extends in the X-axis positive direction. With this configuration, the support portion 120 as a whole has a U-shape that opens in the X-axis positive direction.

[0061] As shown in Figure 6, the supported portion 510 of the side member 500 is inserted between the first support portion 121 and the second support portion 125 of the support portion 120. The first support portion 121 has a surface in the negative Z-axis direction that contacts the supported portion 510, thereby restricting the movement of the support portion 120 in the Z-axis direction. The supported portion 510 is a plate-shaped portion with its thickness direction oriented in the Z-axis direction. In this embodiment, as shown in Figures 1, 2, 6, and 7, the side member 500 is arranged along the outer surface 102a of the insulating member 100. In this embodiment, the outer surface 102a of the insulating member 100 is the surface of the side wall portion 102 of the insulating member 100 that is opposite to the energy storage element 20. More specifically, the side member 500 is arranged such that the side body portion 501 is aligned with the outer surface 102a of the plurality of insulating members 100A and 100B included in the insulating member 100. As a result, the supported portion 510 of the side member 500 is positioned between the first support portion 121 and the second support portion 125 in each of the multiple support portions 120.

[0062] In the energy storage device 10 according to this embodiment, there are two protrusions between the supported portion 510 and the second support portion 125, which protrude from one of the supported portion 510 and the second support portion 125 toward the other and are spaced apart in the X-axis direction. This allows the position of the insulating member 100 in the Z-axis direction to be determined with high precision and reduces stress concentration in the support portion 120. More specifically, in this embodiment, as shown in Figures 5 to 7, the second support portion 125 includes a first protrusion 131 and a second protrusion 135 that protrude toward the supported portion 510. In the second support portion 125 extending in the X-axis direction, the first protrusion 131 is positioned near the edge in the positive X-axis direction, and the second protrusion 135 is positioned near the connecting portion 128.

[0063] In this embodiment, as shown in Figure 5, before the supported portion 510 is positioned between the first support portion 121 and the second support portion 125, the first protrusion 131 is closer to the first support portion 121 in the Z-axis direction than the second protrusion 135. Therefore, as shown in Figure 6, when the supported portion 510 is positioned between the first support portion 121 and the second support portion 125, the support portion 120 can be elastically deformed by the contact between the first protrusion 131 and the supported portion 510. The resulting restoring force of the support portion 120 acts to align the position of the first support portion 121 of the support portion 120 in the Z-axis direction with respect to the supported portion 510.

[0064] In other words, the position in the Z-axis direction of the insulating member 100A equipped with the support portion 120 is determined to a predetermined position with respect to the supported portion 510. As a result, the Z-axis position of the energy storage element 20 supported by the support portion 120 (more specifically, the first support portion 121) of the insulating member 100A is precisely aligned to the correct position. This effect can be obtained in multiple support portions 120 into which the supported portion 510 extending in the Y-axis direction is inserted. In other words, the Z-axis positions of multiple insulating members 100A and 100B arranged in the Y-axis direction can be aligned by the supported portion 510 extending in the Y-axis direction.

[0065] Therefore, for example, it becomes easy to bring multiple energy storage elements 20 into contact with a temperature control member (not shown) that is placed on the installation member 800 (see Figure 1) and is used for cooling the energy storage device 10. An example of a temperature control member is a device that exchanges heat with multiple energy storage elements 20 by a liquid or gas flowing inside. The temperature control member may also be a device that cools or heats multiple energy storage elements 20 by electrical means, for example. Other materials such as a heat conductive sheet or a heat conductive adhesive may be interposed between the multiple energy storage elements 20 and the temperature control member. In this case, the other material such as the heat conductive sheet or heat conductive adhesive can come into contact with the first side surface 21a of the energy storage element 20. When the temperature control member comes into contact with the bottom surface (first side surface 21a) of the multiple energy storage elements 20, at least a portion of the load from the energy storage device 10 may be borne by the temperature control member.

[0066] In this embodiment, the second projection 135 is positioned between the first projection 131 and the connecting portion 128 in the X-axis direction. As shown in Figure 6, when the supported portion 510 is positioned between the first support portion 121 and the second support portion 125, a gap (space) is formed between the second projection 135 and the supported portion 510 in the Z-axis direction. Under normal conditions, when the energy storage device 10 is not experiencing vibration or shock, the first support portion 121 and the supported portion 510 are in contact, and the first projection 131 and the supported portion 510 are also in contact. However, the second projection 135 and the supported portion 510 are separated and do not come into contact. Under normal conditions, the distance between the first projection 131 and the first support portion 121 is the same as the thickness of the supported portion 510, and the distance between the second projection 135 and the first support portion 121 is greater than the thickness of the supported portion 510.

[0067] In this state, for example, if the energy storage element 20 attempts to move in the positive Z-axis direction due to vibration or shock to the energy storage device 10, as shown in Figure 7, the second support portion 125 of the insulating member 100A receives a force in the negative Z-axis direction from the supported portion 510 via the first projection portion 131. As a result, the second support portion 125 elastically deforms so that its end in the positive X-axis direction is displaced in the negative Z-axis direction. Specifically, the supported portion 510 and the second support portion 125 are displaced in the XZ plane. Depending on the direction of the vibration or shock, the supported portion 510 and the second support portion 125 may be displaced so that they tilt and rotate in the XZ plane around the Y-axis direction. At this time, there is a second projection portion 135 that protrudes toward the supported portion 510 at a position closer to the connection portion 128 than the first projection portion 131. As a result, the second projection portion 135 comes into contact with the supported portion 510. Unlike the normal state, if the energy storage device 10 experiences vibration or shock, the second protrusion 135 does not contact the supported portion 510, but instead a gap is created between the first support portion 121 and the supported portion 510, causing them to separate. As a result, the external force from the supported portion 510 is absorbed by the second protrusion 135, which is less likely to be displaced or deformed due to its proximity to the connection portion 128. Therefore, the amount of deformation of the second support portion 125 is smaller than the amount of deformation that would occur if the second protrusion 135 were not present. Note that the first protrusion 131 and the supported portion 510 remain in contact, both in the normal state and in abnormal states.

[0068] In other words, the stress concentration in the support portion 120 due to the large deformation of the second support portion 125 is alleviated, and as a result, damage to the insulating member 100A caused by stress concentration is suppressed. These effects of the first protrusion 131 and the second protrusion 135 are also achieved when at least one of the first protrusion 131 and the second protrusion 135 is provided to protrude from the supported portion 510 toward the second support portion 125. A configuration in which the supported portion 510 has two protrusions that protrude toward the second support portion 125 will be described later as a modification of the embodiment.

[0069] In this embodiment, the first protrusion 131 and the second protrusion 135 are integrally provided on the second support portion 125. As shown in Figures 5 to 7, the thickness of the portion of the second support portion 125 that forms the second protrusion 135 is greater than the thickness of the portion of the second support portion 125 that forms the first protrusion 131. This makes the second support portion 125 less susceptible to deformation when the second protrusion 135 is subjected to a force in the negative Z-axis direction. In this embodiment, the thickness of the connecting portion 128 is greater than the thickness of the portion of the second support portion 125 that forms the second protrusion 135. This makes the second support portion 125 even less susceptible to deformation when the second protrusion 135 is subjected to a force in the negative Z-axis direction.

[0070] The technical features of the energy storage device 10 according to the embodiment configured as described above can be explained, for example, as follows.

[0071] The energy storage device 10 according to this embodiment includes an energy storage element 20, an insulating member 100 arranged along the energy storage element 20 and supporting the energy storage element 20, and a side member 500 arranged along the outer surface 102a of the insulating member 100. The insulating member 100 includes a support portion 120 that supports the energy storage element 20. The support portion 120 includes a first support portion 121, a connecting portion 128, and a second support portion 125. The first support portion 121 supports the first side surface 21a of the energy storage element 20 and extends to one side in the X-axis direction (in this embodiment, the negative X-axis direction) along the first side surface 21a. The connecting portion 128 is provided at the end of the first support portion 121 in the negative X-axis direction. The second support portion 125 is connected to the connecting portion 128 and extends to the other side in the X-axis direction (in this embodiment, the positive X-axis direction). The side member 500 includes a supported portion 510 positioned between the first support portion 121 and the second support portion 125. One of the second support portion 125 and the supported portion 510 has a first projection 131 that protrudes toward the other, and one of the second support portion 125 and the supported portion 510 has a second projection 135 that protrudes toward the other. The second projection 135 is positioned between the first projection 131 and the connecting portion 128 in the X-axis direction.

[0072] As described above, in the energy storage device 10 according to this embodiment, the supported portion 510 of the side member 500 is positioned between the first support portion 121 and the second support portion 125 of the support portion 120 provided by the insulating member 100. As a result, the insulating member 100 and the energy storage element 20 can be restricted from moving by the side member 500. Furthermore, one of the second support portion 125 and the supported portion 510 has a second protrusion 135 that protrudes toward the other at a position closer to the connection portion 128 than the first protrusion 131. Therefore, when the energy storage element 20 attempts to move away from the supported portion 510 due to impact or vibration, the second protrusion 135 comes into contact with the other, preventing the support portion 120 from deforming and opening. As a result, stress concentration in the support portion 120 is alleviated. This prevents damage to the insulating member 100, etc. Thus, according to the energy storage device 10 of this embodiment, the movement of the energy storage element 20 can be restricted by the insulating member 100, and the resistance of the insulating member 100 to vibration or shock is improved. Therefore, the energy storage device 10 of this embodiment is an energy storage device with improved reliability.

[0073] In this embodiment, the insulating member 100A that supports the energy storage elements 20 on both sides in the Y-axis direction, and the insulating member 100B that supports the energy storage element 20 on one side in the Y-axis direction, each have a support portion 120. Therefore, the above-mentioned effect of improved resistance to vibration or shock is achieved in each of the insulating members 100A and 100B.

[0074] The insulating member 100 does not need to be composed of multiple insulating members 100A and 100B. In other words, the insulating member 100 does not need to be composed of multiple spacers or cell holders. For example, the insulating member 100 may be realized by other insulating members that collectively cover the third side surfaces 21c (see Figures 3 and 4) of multiple energy storage elements 20 arranged in the Y-axis direction. Even in this case, the other insulating members can be provided with support parts as shown in Figures 5 to 7, etc., to improve resistance to vibration or shock.

[0075] In this embodiment, as shown in Figures 5 to 7, the first protrusion 131 and the second protrusion 135 are provided on the second support portion 125. More specifically, the first protrusion 131 and the second protrusion 135 are integrally provided on the second support portion 125.

[0076] In this configuration, the second support portion 125 is provided with a first protrusion 131 that primarily serves to restrict the movement of the insulating member 100 under normal conditions, and a second protrusion 135 that primarily serves to suppress large deformation of the support portion 120. In other words, since the second support portion 125, which is a single part, has at least two functions, the reliability of the energy storage device 10 is improved with a simple configuration.

[0077] In this embodiment, as shown in Figures 3 and 4, the insulating member 100 includes a first insulating member 100Aa and a second insulating member 100Ab, which are arranged on one side and the other side of the energy storage element 20 in the Y-axis direction. The side member 500 is arranged along the outer surfaces 102a of the first insulating member 100Aa and the second insulating member 100Ab, and the supported portion 510 is arranged between the first support portion 121 and the second support portion 125 of the support portion 120 of the first insulating member 100Aa and the second insulating member 100Ab.

[0078] Thus, in this embodiment, the side member 500 can collectively restrict the movement of the first insulating member 100Aa and the second insulating member 100Ab, which are adjacent to each other in the Y-axis direction with the energy storage element 20 in between. Therefore, it is easy to maintain the energy storage element 20 in a state where its movement is restricted by the first insulating member 100Aa and the second insulating member 100Ab. In this embodiment, the movement of the insulating member 100B (see Figure 2) and the insulating member 100A adjacent to insulating member 100B is also collectively restricted by the side member 500. In other words, at the support portions 120 of the respective insulating members 100A and 100B adjacent to each other in the Y-axis direction, the supported portion 510 is positioned between the first support portion 121 and the second support portion 125.

[0079] In this embodiment, the support portion 120 that supports the first side surface 21a of the energy storage element 20 covers only a part of the first side surface 21a, so a part of the first side surface 21a is exposed. That is, when viewed from the Z-axis direction (more specifically the negative Z-axis direction), which is the direction in which the first side surface 21a faces, the energy storage element 20 has an exposed portion 21a1 in the negative X-axis direction of the support portion 120 (see Figures 5 and 6), where a part of the first side surface 21a is exposed. The exposed portion 21a1 is formed by a part of the first side surface 21a. More specifically, since the insulating members 100A and 100B have a pair of support portions 120, when viewed from the negative Z-axis direction, the first side surface 21a has an exposed portion 21a1 between the pair of support portions 120 in the X-axis direction.

[0080] In this configuration, the support portion 120 is restricted from moving in the Z-axis direction by the side member 500, and an exposed portion 21a1 is provided on a part of the first side surface 21a supported by the support portion 120. Therefore, temperature control of the energy storage element 20 using the exposed portion 21a1 is easy. For example, it is easy to bring a temperature control member (not shown) into contact with the exposed portion 21a1 of the energy storage element 20. This allows for efficient cooling or heating of the energy storage element 20. This contributes to improving the reliability of the energy storage device 10. In this embodiment, the exposed portions 21a1 of multiple energy storage elements 20 are aligned in the Y-axis direction, and misalignment of these multiple exposed portions 21a1 in the Z-axis direction is suppressed. Therefore, it is easy to bring multiple exposed portions 21a1 into contact with the temperature control member all at once.

[0081] In this embodiment, as shown in Figures 5 to 7, the second support portion 125 is provided with an inclined portion 132 on the other side in the X-axis direction from the first protruding portion 131 (the positive X-axis direction in Figures 5 to 7). The inclined portion 132 forms an inclined surface 132a that moves away from the first support portion 121 as it moves toward the positive X-axis direction.

[0082] This configuration allows the supported portion 510 to be smoothly inserted between the first support portion 121 and the second support portion 125. As a result, problems such as a part of the second support portion 125 colliding with the supported portion 510 in the insertion direction when inserting the supported portion 510 between the first support portion 121 and the second support portion 125 are less likely to occur. In other words, defects such as damage to the insulating member 100 or the side member 500 during the manufacturing of the energy storage device 10 are less likely to occur.

[0083] In this embodiment, as shown in Figures 5 to 7, the inclined surface 132a and the Z-axis positive surface of the first projection 131 are continuous, but a clear boundary may exist between the inclined surface 132a and the Z-axis positive surface of the first projection 131. It may also be described as the inclined surface 132a being formed by a part of the first projection 131.

[0084] In this embodiment, a gap is formed between the second protrusion 135 provided on one of the second support portion 125 and the supported portion 510, and the other of the second support portion 125 and the supported portion 510. More specifically, as shown in Figure 6, a gap is formed between the second protrusion 135 provided on the second support portion 125 and the supported portion 510.

[0085] With this configuration, the second protrusion 135 is less likely to get in the way when inserting the supported portion 510 between the first support portion 121 and the second support portion 125. Therefore, the work of inserting the supported portion 510 between the first support portion 121 and the second support portion 125 can be performed efficiently. When a gap is provided between the second protrusion 135 and the supported portion 510, deformation of the second support portion 125 in the range up to the point where the second protrusion 135 and the supported portion 510 come into contact becomes more permissible. This is advantageous from the viewpoint of obtaining the effect of the support portion 120 in absorbing the dimensional tolerance of the supported portion 510.

[0086] The above description of the energy storage device 10 according to the embodiment focuses on the configuration of the support portion 120 and its surroundings provided by the insulating member 100. However, the configuration of the support portion 120 and its surroundings in the energy storage device 10 may differ from the configuration shown in Figures 2 to 7. Therefore, the following describes modified examples of the configuration of the support portion 120 and its surroundings, focusing on the differences from the above embodiment.

[0087] [4. Modified Forms] Figure 8 is a cross-sectional view showing the configuration of the support portion 120a and its surrounding area according to a modified form of the embodiment. The position of the cross-section in Figure 8 corresponds to the position of the cross-section in Figure 5. In Figure 8, the cross-sections of the insulating member 100 (more specifically the first insulating member 100Aa), the energy storage element 20, and the side member 500a according to this modified form are simply illustrated.

[0088] The modified energy storage device 10a comprises an energy storage element 20 and an insulating member 100. The insulating member 100 includes a support portion 120a. Figure 8 shows the configuration of the support portion 120a and its surroundings provided by the insulating member 100A included in the insulating member 100. The modified energy storage device 120a comprises a first support portion 121 and a second support portion 125a. A supported portion 510a provided by a side member 500a is positioned between the first support portion 121 and the second support portion 125a. One of the second support portion 125a and the supported portion 510a has a first protruding portion 131a that protrudes toward the other. One of the second support portion 125a and the supported portion 510a has a second protruding portion 135a that protrudes toward the other. The second protruding portion 135a is positioned between the first protruding portion 131a and the connecting portion 128 in the X-axis direction. These configurations are common to the energy storage device 10 according to the embodiment.

[0089] In the modified energy storage device 10a, the support portion 120a has a first protruding portion 131a and a second protruding portion 135a that protrude toward the second support portion 125a, and in this respect it differs from the energy storage device 10 according to the embodiment.

[0090] In the modified support portion 120a, as shown in Figure 8, when the supported portion 510a is positioned between the first support portion 121 and the second support portion 125a, the support portion 120a can be elastically deformed by the contact between the second support portion 125a and the first projection portion 131a. The resulting restoring force of the support portion 120a acts to align the position of the first support portion 121 of the support portion 120a in the Z-axis direction with respect to a predetermined position relative to the supported portion 510a. Furthermore, when the second support portion 125a deforms due to receiving a force in the negative Z-axis direction from the supported portion 510a via the first projection portion 131a, the second projection portion 135a contacts the contact portion 126 of the second support portion 125a. As a result, the external force from the second projection portion 135a is received by the contact portion 126, which is less likely to be displaced because it is close to the connection portion 128. Therefore, the amount of deformation of the second support portion 125a is smaller than the amount of deformation that would occur if the second protrusion portion 135a were absent. In other words, the stress concentration in the support portion 120a caused by the large deformation of the second support portion 125a is alleviated, and as a result, damage to the insulating member 100A caused by stress concentration is suppressed.

[0091] In this modified example, the first protrusion 131a and the second protrusion 135a are formed by a part of the plate-shaped supported portion 510a bulging out in the negative Z-axis direction, and recesses are provided on the back side of each of the first protrusion 131a and the second protrusion 135a. However, this configuration is not essential. The first protrusion 131a and the second protrusion 135a may each be provided on the supported portion 510a as a thickened portion of the plate-shaped supported portion 510a.

[0092] In this modified example, both the first protrusion 131a and the second protrusion 135a are provided on the supported portion 510a, but only one of the first protrusion 131a and the second protrusion 135a may be provided on the supported portion 510a. For example, a second support portion 125 having only the first protrusion 131 of the first and second protrusions 131 and the supported portion 510a having only the second protrusion 135a of the first and second protrusions 131a and the second protrusions 135a may be combined. Alternatively, a second support portion 125 having only the second protrusion 135 of the first and second protrusions 131 and the second protrusions 135 may be combined with a supported portion 510a having only the first protrusion 131a of the first and second protrusions 135a.

[0093] [5. Other Modifications] The energy storage device 10 according to this embodiment and its modifications have been described above, but the present invention is not limited to the above embodiment and its modifications. The embodiments disclosed herein are illustrative and not restrictive in all respects, and the scope of the present invention includes all modifications in the sense and scope equivalent to the claims.

[0094] The support portion 120 of the insulating member 100 may be positioned to support the fourth side surface 21d, which is the terminal arrangement surface of the container 21, rather than the first side surface 21a. In other words, the first side surface of the container 21 supported by the support portion 120 may be the terminal arrangement surface of the container 21. That is, the support portion 120 may be positioned at the Z-axis end of the insulating main body 101, and the configuration of the support portion 120 may be the inverse of the configuration shown in Figures 5 to 7. Even in this case, the insulating member 100 and the energy storage element 20 can be restricted from moving by the side member 500, and the second protrusion 135 contacts the supported portion 510, which prevents the support portion 120 from deforming to open.

[0095] The first protrusion 131 and the second protrusion 135 provided on the support portion 120 may be separate components from the second support portion 125 and the supported portion 510. For example, by arranging a component on the surface of the flat second support portion (for example, the second support portion 125a shown in Figure 8) facing the supported portion 510, at least one of the first protrusion 131 and the second protrusion 135 may be formed by the component. In this case, the options for the material forming the first protrusion 131 and / or the second protrusion 135 are broadened. For example, the material forming the first protrusion 131 and / or the second protrusion 135 may be made of a material with higher or lower rigidity than the material forming the insulating member 100.

[0096] It is not necessary for all of the multiple insulating members 100A and 100B included in the insulating member 100 to have the support portion 120 shown in Figures 5 to 7. If one or more of the multiple insulating members 100A and 100B have a support portion 120 provided with a first protrusion 131 and a second protrusion 135, the resistance to vibration or shock will be improved in that one or more insulating members 100A or 100B.

[0097] The insulating member 100 does not necessarily have to include an insulating member 100A capable of supporting two energy storage elements 20 arranged on both sides of the insulating main body 101 in the Y-axis direction. For example, an insulating member 100B (see Figure 2) that supports only one energy storage element 20 may be placed for each of the multiple energy storage elements 20. However, from the viewpoint of more stably supporting each of the multiple energy storage elements 20, it is preferable to place an insulating member 100A between two adjacent energy storage elements 20 in the Y-axis direction.

[0098] It is not essential that the exposed portion 21a1 is formed by a part of the first side surface 21a of the energy storage element 20. The portion of the first side surface 21a corresponding to the exposed portion 21a1 may be covered by an insulating member 100 or other member. In this case, for example, the energy storage element 20 may be cooled by bringing a temperature control member into contact with the third side surface 21c, which is the short side of the container 21, or the fourth side surface 21d, which is the terminal arrangement surface of the container 21.

[0099] The second support portion 125 does not necessarily have an inclined portion 132 that forms an inclined surface 132a. If the second support portion 125 does not have an inclined portion 132, it is preferable that the curved surface of the first projection 131 that protrudes toward the supported portion 510 forms a bent surface, from the viewpoint of enabling the supported portion 510 to be smoothly inserted between the first support portion 121 and the second support portion 125.

[0100] The various supplementary details regarding the energy storage device 10 according to the above embodiment may be appropriately applied to the modified energy storage device 10a (see Figure 8). Configurations constructed by arbitrarily combining the components included in the above embodiment and its modified form are also within the scope of the present invention.

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

[0102] 10, 10a Energy storage device 20 Energy storage element 21a First side surface 21a1 Exposed part 30 Energy storage element row 100, 100A, 100B Insulating member 100Aa First insulating member 100Ab Second insulating member 101 Insulating main body part 102a Outer surface 120, 120a Support part 121 First support part 125, 125a Second support part 128 Connection part 131, 131a First protruding part 132 Inclined part 132a Inclined surface 135, 135a Second protruding part 500, 500a Side member 510, 510a Supported part

Claims

1. An energy storage device comprising: an energy storage element; an insulating member disposed along the energy storage element and supporting the energy storage element; and a side member disposed along the outer surface of the insulating member, wherein the insulating member includes a support portion for supporting the energy storage element; the support portion includes a first support portion that supports the first side surface of the energy storage element and extends to one side in a first direction along the first side surface; a connecting portion provided at the end of the first support portion on the one side in the first direction; and a second support portion connected to the connecting portion and extending to the other side in the first direction; the side member includes a supported portion disposed between the first support portion and the second support portion; one of the second support portion and the supported portion includes a first protruding portion that protrudes toward the other; one of the second support portion and the supported portion includes a second protruding portion that protrudes toward the other; and the second protruding portion is disposed between the first protruding portion and the connecting portion in the first direction.

2. The energy storage device according to claim 1, wherein the first projection and the second projection are provided on the second support portion.

3. The energy storage device according to claim 1 or 2, wherein the insulating member includes a first insulating member and a second insulating member, respectively, arranged on one side and the other side of the energy storage element in a second direction intersecting the first direction, the side member is arranged along the outer surfaces of the first insulating member and the second insulating member, and the supported portion is arranged between the first support portion and the second support portion provided by the support portions of the first insulating member and the second insulating member.

4. The energy storage device according to claim 1 or 2, wherein, when viewed from a third direction which is the direction in which the first side surface faces, the energy storage element has an exposed portion on one side of the support portion in the first direction in which a part of the first side surface is exposed.

5. The energy storage device according to claim 1 or 2, wherein the second support portion is provided with an inclined portion that forms an inclined surface on the other side in the first direction from the first protrusion portion, in which the inclined surface moves away from the first support portion as it moves toward the other side.

6. The energy storage device according to claim 1 or 2, wherein a gap is formed between the second protruding portion and the other of the second support portion and the supported portion.

Images