Power storage device and vehicle

Abstract

To improve the durability of a power storage device having a cell connection.SOLUTION: A power storage device (battery 100) comprises a case 300 and a cell connection (cell connections 10, 20) housed within the case 300. The cell connection comprises a plurality of power storage cells (power storage cells 11 to 14, 21 to 24) and connection sections (connection sections 2A, 2B) that electrically connect the power storage cells to each other. The power storage device further comprises holding members (holding members 51, 52) for holding at least one power storage cell between the inner surface of the case 300 and the cell connection.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a power storage device and a vehicle equipped with the power storage device. [Background technology]

[0002] JP 2023-502457 A (Patent Document 1) discloses a rectangular parallelepiped battery (electricity storage device) having a length L of 400 mm to 2500 mm and a ratio of length L to width H (L / H) of 4 to 21. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2023-502457 Summary of the Invention [Problem to be solved by the invention]

[0004] In the energy storage device described in Patent Document 1, a plurality of electrode assembly sets (energy storage cells) connected in series and arranged in a row are disposed in a case (housing). Hereinafter, a series of a plurality of energy storage cells connected in a row will be referred to as a "cell series."

[0005] In the electricity storage device described in Patent Document 1, if the cell assembly moves excessively within the case, the connections between the electricity storage cells are likely to be damaged.

[0006] The present disclosure has been made to solve the above-mentioned problems, and an object of the present disclosure is to improve the durability of an electricity storage device including a cell connected body. [Means for solving the problem]

[0007] According to an embodiment of a first aspect of the present disclosure, there is provided a power storage device as described below.

[0008] (Item 1) The energy storage device includes a case and a cell assembly housed in the case. The cell assembly includes a plurality of energy storage cells and connection parts that electrically connect the energy storage cells to each other. The energy storage device further includes one or more holding members that hold at least one of the plurality of energy storage cells between the inner surface of the case and the cell assembly.

[0009] In the above configuration, at least one of the plurality of energy storage cells included in the cell assembly is held by the holding member, making the cell assembly less likely to move. This makes the connections between the energy storage cells less susceptible to damage. The above configuration improves the durability of the energy storage device against external impacts and the like. The connection may be a conductive member. The connection may electrically connect the electrodes of adjacent energy storage cells by connecting the electrodes of the adjacent energy storage cells. The positive electrode of one of two adjacent energy storage cells may be connected to the negative electrode of the other energy storage cell by the connection.

[0010] (Item 2) In the energy storage device described in item 1, the one or more holding members include a first holding member formed along the cell assembly and holding a first surface of each of the plurality of energy storage cells.

[0011] As described above, one holding member (first holding member) holds the first surfaces of the energy storage cells included in the connected cell body, so that the number of parts can be reduced and the connected cell body can be held appropriately.

[0012] (Item 3) The electricity storage device according to item 2 includes a plate-shaped first main body portion and one or more first protrusions protruding from the first main body portion toward the cell connected body.

[0013] According to the first holding member having the above configuration, the movement of the cell connected body can be easily restricted by the first protrusion.

[0014] (Item 4) In the energy storage device described in item 2 or 3, the one or more holding members further include a second holding member formed along the cell assembly and holding a second surface opposite to the first surface of each of the plurality of energy storage cells.

[0015] The second holding member holds the second surfaces of the energy storage cells included in the cell assembly, so that the first holding member and the second holding member can sandwich the energy storage cells included in the cell assembly. This configuration makes it easier to hold the cell assembly accurately.

[0016] (Item 5) In the electricity storage device described in item 4, the second holding member includes a plate-shaped second main body portion and one or more second protrusions protruding from the second main body portion toward the cell connected body.

[0017] According to the second holding member having the above-described configuration, the movement of the cell connected body can be more easily restricted by the second protrusion.

[0018] (Item 6) In the energy storage device described in any one of items 2 to 5, at least one of the first holding member and the second holding member is formed with a flow path for discharging gas generated from at least one of the plurality of energy storage cells.

[0019] According to the above configuration, gas generated from the electricity storage cell can be easily and appropriately discharged.

[0020] (Item 7) In the electricity storage device according to any one of items 2 to 6, at least one of the first holding member and the second holding member has a hollow structure.

[0021] As described above, by forming a cavity inside at least one of the first holding member and the second holding member, external impacts applied to the case can be more easily absorbed by at least one of the first holding member and the second holding member.

[0022] (Item 8) In the electricity storage device according to any one of items 4 to 7, the second holding member has higher thermal conductivity than the first holding member.

[0023] In the above-described electricity storage device, the second holding member located on the second surface side of the electricity storage cell has high thermal conductivity, so that the electricity storage cell can be easily heated or cooled from the second surface side of the electricity storage cell.

[0024] (Item 9) In the electricity storage device described in item 8, the second holding member includes metal, and the first holding member includes resin.

[0025] As described above, the second holding member containing metal increases the thermal conductivity of the second holding member, while the first holding member containing resin has excellent toughness and formability, making it easier to hold the energy storage cells included in the cell assembly.

[0026] (Item 10) In the electricity storage device according to any one of items 4 to 9, the first holding member and the second holding member each have a tapered surface at an end thereof.

[0027] As described above, by forming a tapered surface at the end of each holding member, it becomes easier to insert the cell assembly to which the first holding member and the second holding member are attached into the case.

[0028] (Item 11) In the energy storage device according to any one of items 4 to 10, the cell connected body, the first holding member, and the second holding member are integrated by winding a wire-, band-, or sheet-shaped member.

[0029] By integrating the cell connected body, the first holding member, and the second holding member as described above, misalignment is less likely to occur.

[0030] (Item 12) In the energy storage device according to any one of items 1 to 11, the case has a rectangular parallelepiped outer shape. The case has four faces extending in the connecting direction of the cell assembled body and two faces covering the ends of the cell assembled body. The four faces include a pair of opposing faces, that is, first opposing faces, and a second opposing face, that is, an opposing face having an area larger than that of the first opposing faces. The holding member is disposed on the first opposing faces.

[0031] As described above, by arranging the holding members on the opposing surfaces (a pair of opposing surfaces) with small areas, it becomes easier to reduce the dimensions of the holding members that hold the energy storage cells.

[0032] According to an embodiment of the second aspect of the present disclosure, there is provided a vehicle as follows.

[0033] (13) The vehicle includes the power storage device according to any one of the first to twelfth paragraphs.

[0034] In the vehicle, the durability of the power storage device including the cell connected body is improved. [Effects of the Invention]

[0035] According to the present disclosure, it is possible to improve the durability of an electricity storage device including a cell connected body. [Brief explanation of the drawings]

[0036] [Figure 1] 1 is a diagram illustrating a configuration of a power storage device according to an embodiment of the present disclosure. [Figure 2] 2 is an enlarged perspective view showing the inside of a case of the electricity storage device shown in FIG. 1. FIG. [Figure 3] 2 is a diagram for explaining the configuration of each cell connected body shown in FIG. 1. FIG. [Figure 4] 2 is an exploded perspective view of a storage cell included in each of the cell connected bodies shown in FIG. 1. FIG. [Figure 5] FIG. 2 is a cross-sectional view taken along line VV in FIG. [Figure 6] FIG. 2 is a cross-sectional view taken along line VI-VI in FIG. [Figure 7] FIG. 2 is a diagram showing a first modified example of the power storage device shown in FIG. [Figure 8] 6 is a cross-sectional view corresponding to FIG. 5 of a power storage device according to a first modified example. FIG. [Figure 9] 7 is a cross-sectional view corresponding to FIG. 6 of a power storage device according to a first modified example. FIG. [Figure 10] 1. FIG. 5 is a diagram showing a second modified example of the power storage device shown in FIG. [Figure 11] 1. FIG. 6 is a diagram showing a third modified example of the power storage device shown in FIG. [Figure 12] 1. FIG. 6 is a diagram showing a fourth modified example of the power storage device shown in FIG. [Figure 13] 1. FIG. 9 is a diagram showing a fifth modified example of the power storage device shown in FIG. [Figure 14] 1. FIG. 9 is a diagram showing a sixth modified example of the power storage device shown in FIG. [Figure 15] 1. FIG. 10 is a diagram showing a seventh modification of the power storage device shown in FIG. [Figure 16] 1. FIG. 10 is a diagram illustrating an eighth modification of the power storage device illustrated in FIG. [Figure 17] 1. FIG. 13 is a diagram illustrating a ninth modification of the power storage device illustrated in FIG. [Figure 18] FIG. 13 is a diagram illustrating a tenth modification of the power storage device shown in FIG. [Figure 19] FIG. 13 is a diagram illustrating an eleventh modification of the power storage device shown in FIG. [Figure 20] FIG. 13 is a diagram showing a twelfth modification of the power storage device shown in FIG. [Figure 21] FIG. 21 is a cross-sectional view taken along line XXI-XXI in FIG. 20. [Figure 22] FIG. 1 is a diagram illustrating an example of a power storage module including a plurality of batteries. [Figure 23] 23 is a diagram showing an example of a vehicle equipped with the power storage module shown in FIG. 22. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0037] Embodiments of the present disclosure will be described in detail with reference to the drawings. In the drawings, identical or corresponding parts are designated by the same reference numerals, and their description will not be repeated. In each of the drawings used below, of the mutually orthogonal X-axis, Y-axis, and Z-axis, the X-axis indicates a first in-plane direction of the battery (e.g., the length direction), the Y-axis indicates a second in-plane direction of the battery (e.g., the width direction), and the Z-axis indicates the height direction of the battery. Hereinafter, the directions indicated by the arrows of the X-axis, Y-axis, and Z-axis will be indicated with a "+" and the opposite directions will be indicated with a "-".

[0038] Fig. 1 is a diagram for explaining the configuration of the electricity storage device according to this embodiment. "Case internal configuration diagram-Z" in Fig. 1 is a diagram of the contents of the case as seen from the +Z side. "Case internal configuration diagram-Y" in Fig. 1 is a diagram of the contents of the case as seen from the +Y side.

[0039] The power storage device according to this embodiment is a battery 100 shown in FIG. 1. The battery 100 is a secondary battery such as a lithium-ion battery, a nickel-metal hydride battery, or a sodium-ion battery. Examples of lithium-ion batteries include an LFP battery that uses lithium iron phosphate as the positive electrode active material, or a ternary battery that uses NMC (nickel-manganese-cobalt) as the positive electrode active material. The secondary battery may be a liquid secondary battery or an all-solid-state secondary battery. As will be described in detail later, the battery 100 includes multiple storage cells that each function as a secondary battery. The battery 100 may include only storage cells of the same type (e.g., only LFP batteries) or may include storage cells of different types (e.g., an LFP battery and a ternary battery).

[0040] The battery 100 includes a case 300. The case 300 has a rectangular parallelepiped outer shape. The case 300 has a pair of faces F1 and F2 (first opposing faces) facing each other in the Z direction, a pair of faces F3 and F4 (second opposing faces) facing each other in the Y direction, and faces F5 and F6 (X-direction end faces) located at the ends in the X direction. The area of ​​each of the faces F1 and F2 is smaller than the area of ​​each of the faces F3 and F4. The length (dimension in the X direction) of the case 300 is longer than the width (dimension in the Y direction) of the case 300. The length of the case 300 may be 250 mm or more and 5000 mm or less, for example, approximately 1000 mm. The width of the case 300 may be 10 mm or more and 1250 mm or less, for example, approximately 50 mm. The ratio of the length of the case 300 to the width of the case 300 may be 4 or more and 25 or less. The height (dimension in the Z direction) of the case 300 may be 10 mm or more and 1250 mm or less, for example, about 100 mm, but the dimensions of the case 300 are not limited to the above.

[0041] The case 300 includes a main body 310 and a lid 320. The main body 310 is, for example, a cylindrical housing with a bottom and an opening on the end face on the +X side, and houses the cell assemblies 10 and 20. The lid 320 is a plate-like member (cover member) having an outer shape corresponding to the opening of the main body 310, and closes the opening on the +X side of the main body 310. The main body 310 and the lid 320 may be made of the same material or different materials. For example, metal can be used as the material constituting each of the main body 310 and the lid 320. The case 300 may be made of aluminum. However, these materials can be changed as appropriate. For example, the lid 320 may be made of an insulating material.

[0042] The cell connected body 10 includes four energy storage cells 11 to 14 and three connection parts 2A that electrically connect the energy storage cells to each other. The energy storage cells 11 to 14 are connected in a row in the X direction within the case 300. The cell connected body 20 includes four energy storage cells 21 to 24 and three connection parts 2B that electrically connect the energy storage cells to each other within the case 300. The energy storage cells 21 to 24 are connected in a row in the X direction within the case 300. In this manner, the cell connected body 10 and the cell connected body 20 are arranged parallel to the X direction. Each of the faces F1 to F4 of the case 300 extends in the connecting direction (X direction) of the cell connected bodies 10 and 20. Each of the faces F5 and F6 of the case 300 covers the end portions of the cell connected bodies 10 and 20 in the X direction. Each of the energy storage cells included in the cell connected bodies 10 and 20 is configured to be able to store electricity.

[0043] The cell assembly 10 and the cell assembly 20 are electrically connected within the case 300 of the battery 100. Specifically, as shown in FIG. 1, the -X side end of the cell assembly 10 (the energy storage cell 14) and the -X side end of the cell assembly 20 (the energy storage cell 24) are electrically connected within the case 300 via, for example, a U-shaped connection portion 2C. The connection portion 2C basically has the same structure as the connection portion 2A or 2B, except that it is formed in a different shape (the connection portion 2C has a U-shaped cross section, while the connection portions 2A and 2B each have an I-shaped cross section). The connection portion 2C may be an integrally molded product or a composite of a plurality of separately molded parts. For example, the connection portion 2C may be formed by connecting a protrusion 144B (FIG. 3) protruding from the energy storage cell 14 and a protrusion 144B (FIG. 3) protruding from the energy storage cell 24 via a conductive material (beam portion). The protrusion 144B will be described later.

[0044] The cell connected bodies 10 and 20 are arranged such that the positions of the storage cells and the connection parts are aligned. The storage cells 11, 12, 13, and 14 included in the cell connected body 10 overlap with the storage cells 21, 22, 23, and 24 included in the cell connected body 20 in the Y direction, respectively. That is, all the storage cells included in the cell connected body 10 are arranged so as to face any of the storage cells included in the cell connected body 20 in the Y direction. Hereinafter, the end face on the -Z side of each storage cell may be referred to as a "first face," and the end face on the +Z side of each storage cell (the end face opposite to the first face) may be referred to as a "second face."

[0045] The case 300 further accommodates holding members 51 and 52. Each of the holding members 51 and 52 is located between the inner surface of the case 300 (more specifically, the inner surface of the main body 310) and the connected cell bodies 10 and 20. Each of the connected cell bodies 10 and 20 is formed parallel to the X direction. Each of the holding members 51 and 52 is formed along the connected cell bodies 10 and 20 and is elongated in the X direction. The holding member 51 holds first surfaces of the energy storage cells 11 to 14 included in the connected cell body 10 and first surfaces of the energy storage cells 21 to 24 included in the connected cell body 20. The holding member 52 holds second surfaces of the energy storage cells 11 to 14 included in the connected cell body 10 and second surfaces of the energy storage cells 21 to 24 included in the connected cell body 20. The connected cell bodies 10 and 20 are sandwiched between the holding members 51 and 52. The holding members 51 and 52 make it possible to appropriately hold the cell connected bodies 10 and 20 while reducing the number of parts. The holding members 51 and 52 are examples of the "first holding member" and the "second holding member" according to the present disclosure, respectively. Details of the holding members 51 and 52 will be described later (see FIGS. 5 and 6).

[0046] The +X side end (energy storage cell 11) of the cell connected body 10 is connected to the lid body 320 via a connection terminal T1. The +X side end (energy storage cell 21) of the cell connected body 20 is connected to the lid body 320 via a connection terminal T2. Fig. 2 is an enlarged perspective view showing the +X side end of the cell connected bodies 10, 20 in a state where the holding members 51, 52 have been removed.

[0047] The cover 320 has a sealing hole 321, an external terminal 322, and a connector 323. The sealing hole 321 may be a pressure adjustment hole that adjusts the pressure inside the case 300. The sealing hole 321 has a sealing structure, for example, made of a metal cap (outside the case) and a sealing member (inside the case). This sealing structure ensures airtightness inside the case 300, and when the pressure inside the case 300 exceeds a predetermined level, gas is discharged to the outside of the case 300 through the sealing hole 321. The external terminal 322 includes an electrode tab 322A joined (e.g., laser welded) to the connection terminal T1 ( FIG. 1 ) of the cell assembly 10, and an electrode tab 322B joined (e.g., laser welded) to the connection terminal T2 ( FIG. 1 ) of the cell assembly 20. The electrode tabs 322A and 322B are electrically connected to the energy storage cells 11 and 21, respectively. Each of the electrode tabs 322A and 322B may have an insulating sealing structure made of ceramic, for example, around the periphery of the electrode. In this embodiment, electrode tabs 322A and 322B function as a negative electrode tab and a positive electrode tab, respectively. However, the present invention is not limited to this, and the polarities may be reversed, with electrode tab 322B serving as a negative electrode tab and electrode tab 322A serving as a positive electrode tab. Connector 323 includes, for example, an output terminal that outputs a detection signal indicating a state inside case 300 (e.g., the temperature of each storage cell) detected by one or more sensors inside case 300 to the outside of the case, and an input terminal that inputs a control signal from the outside of the case to one or more devices inside case 300. For example, a temperature sensor may be provided for each storage cell inside case 300.

[0048] The cell assemblies 10 and 20 are inserted into the main body 310 with the holding members 51 and 52 attached. Holding each of the energy storage cells by the holding members 51 and 52 makes it easier to insert the cell assemblies 10 and 20 into the main body 310. The holding members 51 and 52 may be attached before or after welding of the connection portions 2A and 2B (for example, welding of the protrusions 144A and 144B, which will be described later). After the cell assemblies 10 and 20 are inserted into the main body 310 together with the holding members 51 and 52, the main body 310 and the lid 320 are joined together. The main body 310 and the lid 320 are welded together, for example, by laser.

[0049] In this embodiment, the cell connected body 10 and the cell connected body 20 basically have the same configuration. Therefore, hereinafter, when there is no need to distinguish between the energy storage cells 11 to 14 and 21 to 24, they will be referred to as "energy storage cells 1," and when there is no need to distinguish between the connection parts 2A and 2B, they will be referred to as "connection part 2."

[0050] FIG. 3 is a diagram illustrating the configuration of each of the cell connected bodies 10 and 20. As shown in FIG. 3, each cell connected body includes four energy storage cells 1. Connection portions 2 are provided between adjacent energy storage cells 1, and the connection portions 2 electrically connect the energy storage cells 1. Each cell connected body is configured such that the energy storage cells 1 and the connection portions 2 are arranged alternately. In each of the cell connected bodies 10 and 20, the energy storage cells 1 are connected to each other via the connection portions 2. The rigidity of the connection portions 2 is lower than the rigidity of the energy storage cells 1. The energy storage cells 11 to 14 and 21 to 24 are configured from the same energy storage cells 1. By forming the cell connected bodies 10 and 20 using common energy storage cells 1, the manufacture of the battery 100 becomes easier and the manufacturing cost can be reduced.

[0051] However, the configurations of the cell connected bodies 10 and 20 are not limited to the above. Each cell connected body may include energy storage cells of different dimensions or shapes. The number of energy storage cells housed in the case 300 is not limited to eight and can be changed as appropriate. The number of energy storage cells included in each cell connected body may be less than four, may be between five and nineteen, or may be twenty or more.

[0052] In this embodiment, the energy storage cell 1 is a laminate cell having one or more wound bodies. In a laminate cell, one or more wound bodies that function as electrode bodies are covered with a laminate exterior body. In FIG. 2, the energy storage cell is illustrated without the laminate exterior body. The wound body has a structure in which, for example, a positive electrode sheet and a negative electrode sheet are wound with a separator interposed therebetween. Each of the positive electrode sheet and the negative electrode sheet includes an electrode foil and an active material layer.

[0053] Fig. 4 is an exploded perspective view of the energy storage cell 1. The structures of the energy storage cell 1 and the connection portion 2 will be described below with reference to the cross-sectional view in Fig. 3 (XY cross-sectional view of the periphery of the connection portion 2) and Fig. 4.

[0054] As shown in FIG. 4, the energy storage cell 1 includes two wound bodies 110A and 110B, spacers 120A and 120B, terminal members 130A and 130B, and covers 150A and 150B.

[0055] The wound bodies 110A and 110B have coated portions 111A and 111B, electrode tabs 112A and 112B, and electrode tabs 113A and 113B, respectively. Each of the coated portions 111A and 111B is a region of the electrode foil on the positive electrode sheet or the negative electrode sheet where an active material layer is provided. Each of the electrode tabs 112A, 112B, 113A, and 113B is a region of the positive electrode sheet or the negative electrode sheet where the electrode foil is exposed (an uncoated portion where no active material layer is provided). The electrode tabs 112A and 112B are located at the +X side ends of the wound bodies 110A and 110B, respectively. The electrode tabs 113A and 113B are located at the −X side ends of the wound bodies 110A and 110B, respectively.

[0056] The electrode tabs 112A and 112B are arranged to overlap in the Y direction, and a spacer 120A and a terminal member 130A are provided between the electrode tabs 112A and 112B (see FIG. 3). The electrode tabs 113A and 113B are arranged to overlap in the Y direction, and a spacer 120B and a terminal member 130B are provided between the electrode tabs 113A and 113B (see FIG. 3).

[0057] Each of the spacers 120A, 120B contains an insulating material (e.g., synthetic resin) and is insulating. Each of the spacers 120A, 120B has a shape in which the dimension in the Y direction increases with increasing distance from the coated portions 111A, 111B (see FIG. 3). The terminal member 130A is connected to an end face on the +X side of the spacer 120A. The terminal member 130B is connected to an end face on the -X side of the spacer 120B. Each of the terminal members 130A, 130B contains a conductive material (e.g., a metal such as aluminum or copper) and is conductive. The wound body 110A and the wound body 110B are joined to each other (e.g., laser welded) via the terminal members 130A and 130B.

[0058] Each of the current collecting terminals 140A, 140B is a component that constitutes a part of the connection portion 2. The current collecting terminals 140A, 140B have support portions 142A, 142B and protrusions 144A, 144B, respectively. One of the current collecting terminals 140A and 140B functions as a positive electrode current collecting terminal, and the other functions as a negative electrode current collecting terminal. In one example, the positive electrode current collecting terminal is made of aluminum, and the negative electrode current collecting terminal is made of copper.

[0059] Each of the current collecting terminals 140A, 140B is formed in an L-shape. Each of the support portions 142A, 142B is formed in a plate shape on the YZ plane, and each of the protrusions 144A, 144B is formed in a plate shape on the XZ plane. The support portion 142A and the protrusion 144A may be formed separately and then joined together, or may be formed in an integrated state by bending. The support portion 142B and the protrusion 144B may also be formed separately and then joined together, or may be formed in an integrated state by bending. The support portion 142A is joined (e.g., laser welded) to the end surface on the +X side of the terminal member 130A (see FIG. 3). The support portion 142B is joined (e.g., laser welded) to the end surface on the -X side of the terminal member 130B (see FIG. 3).

[0060] The cover 150A covers the end portion of the energy storage cell 1 on the +X side (including the electrode tabs 112A and 112B). However, the cover 150A is provided with a through-hole h1 for the protrusion 144A. The protrusion 144A passes through the through-hole h1 and protrudes toward the +X side of the energy storage cell 1 (see FIG. 3). The cover 150B covers the end portion of the energy storage cell 1 on the -X side (including the electrode tabs 113A and 113B). However, the cover 150B is provided with a through-hole h2 for the protrusion 144B. The protrusion 144B passes through the through-hole h2 and protrudes toward the -X side of the energy storage cell 1 (see FIG. 3).

[0061] As shown in Fig. 3, at the connection portion 2, of two adjacent energy storage cells 1, the protruding portion 144A of one energy storage cell 1 is joined (for example, by laser welding) to the protruding portion 144B of the other energy storage cell 1. The welded portion may be protected with tape or the like. Although not shown in Fig. 4, a laminated outer casing 160 shown in Fig. 3 is provided on the surfaces of the two wound bodies 110A and 110B. The laminated outer casing 160 is, for example, a laminated film, and is provided on the surfaces of the energy storage cells 1.

[0062] The above-described configuration is merely one example of the configuration of the energy storage cell 1 and can be modified as appropriate. For example, the number of wound bodies included in the energy storage cell 1 is not limited to two, and may be one, three, or more. Furthermore, a laminate (for example, a laminate in which a positive electrode sheet and a negative electrode sheet are laminated with a separator interposed therebetween) may be used as the electrode body instead of the wound body.

[0063] Fig. 5 is a cross-sectional view taken along line VV in Fig. 1. Fig. 6 is a cross-sectional view taken along line VI-VI in Fig. 1.

[0064] 5 and 6, an insulating layer 3 containing a resin such as PET (polyethylene terephthalate) is provided on the inner surface of the main body 310 of the case 300. This electrically insulates the case 300 from the components inside the case 300. However, in batteries that ensure sufficient insulation, the insulating layer 3 can be omitted.

[0065] As shown in FIGS. 5 and 6, the holding member 51 is basically formed in a plate shape. However, the holding member 51 includes, in addition to a plate-shaped main body portion (first main body portion), convex portions P11 to P14 (first convex portions) that protrude from the main body portion toward the cell connected bodies 10 and 20. Each of the convex portions P11 to P14 protrudes toward the cell connected bodies 10 and 20 (+Z side). The holding member 52 is also basically formed in a plate shape. However, in addition to a plate-shaped main body portion (second main body portion), the holding member 52 includes convex portions P21 to P24 (second convex portions) that protrude from the main body portion toward the cell connected bodies 10 and 20. Each of the convex portions P21 to P24 protrudes toward the cell connected bodies 10 and 20 (-Z side). Each of the holding members 51 and 52 contains an insulating material (e.g., resin) and has insulating properties. Each of the holding members 51 and 52 may be a single-piece molded product, or may be a composite in which a plurality of separately molded members are joined together.

[0066] As shown in FIG. 5 , the protrusions P11 to P13 have shapes corresponding to the first surfaces of the power storage cells 13 and 23 adjacent to each other in the Y direction, and hold the first surfaces so as to hold the power storage cells 13 and 23 in predetermined positions. Specifically, the protrusions P11 and P12 are located at the ends (corners) of the first surfaces of the power storage cells 13 and 23 in the Y direction, and function as claws. The protrusion P11 catches on the corners of the power storage cell 13, suppressing movement of the power storage cell 13 toward the +Y side. The protrusion P12 catches on the corners of the power storage cell 23, suppressing movement of the power storage cell 23 toward the -Y side. The protrusion P13 engages with the boundary between the first surfaces of the power storage cells 13 and 23, suppressing misalignment of the power storage cells 13 and 23. The protrusions P21 to P23 have shapes corresponding to the second surfaces of the power storage cells 13 and 23 adjacent to each other in the Y direction, and hold the second surfaces so as to hold the power storage cells 13 and 23 in predetermined positions. Specifically, the protrusions P21 and P22 are located at the ends (corners) of the second surfaces of the energy storage cells 13 and 23 in the Y direction and function as claws. The protrusion P21 catches on the corners of the energy storage cell 13 and suppresses movement of the energy storage cell 13 toward the +Y side. The protrusion P22 catches on the corners of the energy storage cell 23 and suppresses movement of the energy storage cell 23 toward the -Y side. The protrusion P23 engages with the boundaries of the second surfaces of the energy storage cells 13 and 23 and suppresses misalignment of the energy storage cells 13 and 23.

[0067] Figure 5 shows only the protrusions P11 to P13 and P21 to P23 that are arranged for the pair of storage cells 13 and 23 adjacent in the Y direction as representative examples, but the protrusions P11 to P13 and P21 to P23 also support other pairs of storage cells adjacent in the Y direction (the pair of storage cells 11, 21, the pair of storage cells 12, 22, and the pair of storage cells 14, 24) using a similar structure.

[0068] As shown in FIG. 6, each of the protrusions P14 and P24 is located between adjacent energy storage cells in the cell assembly 10, similar to the connection portion 2A. Each of the protrusions P14 and P24 has a dimension (dimension in the X direction) corresponding to the spacing between the energy storage cells and functions as a spacer. The protrusion P14 holds the first surfaces of each of two adjacent energy storage cells in the cell assembly 10, and acts to keep the spacing between the adjacent energy storage cells constant. The protrusion P24 holds the second surfaces of each of two adjacent energy storage cells in the cell assembly 10, and acts to keep the spacing between the adjacent energy storage cells constant. For example, as shown in FIG. 6, each of the protrusions P14 and P24 restricts movement of the energy storage cell 12 toward the −X side and movement of the energy storage cell 13 toward the +X side, thereby preventing the energy storage cells 12 and 13 from coming too close to each other.

[0069] 6 shows only the protrusions P14 and P24 arranged around the pair of energy storage cells 12 and 13 as a representative example, but the protrusions P14 and P24 also hold other pairs of adjacent energy storage cells in the cell assembly 10 (the pair of energy storage cells 11 and 12 and the pair of energy storage cells 13 and 14) with a similar structure. Furthermore, each of the holding members 51 and 52 also holds each pair of adjacent energy storage cells in the cell assembly 20 (the pair of energy storage cells 21 and 22, the pair of energy storage cells 22 and 23, and the pair of energy storage cells 23 and 24) with a protrusion having a structure similar to that of the protrusions P14 and P24 for the cell assembly 10 shown in FIG. 6. The protrusions P14 and P24 may be arranged between the connection portion 2A and the connection portion 2B in the Y direction. The protrusions P14 and P24 arranged in this manner function as a spacer common to the cell assembly 10 and 20.

[0070] In the battery 100 according to this embodiment, holding members 51 and 52 are provided between the inner surface of the case 300 and each of the cell connected bodies 10 and 20. The respective energy storage cells included in the cell connected bodies 10 and 20 are held by the holding members 51 and 52. This makes it difficult for the cell connected bodies 10 and 20 to move, and the connections between the energy storage cells are less susceptible to damage. This configuration improves the durability of the battery 100 (energy storage device) against external impacts and the like.

[0071] 1, 5, and 6, the holding members 51 and 52 are arranged on the first opposing surfaces (faces F1 and F2) that are smaller in area than the second opposing surfaces (faces F3 and F4). By arranging the holding members 51 and 52 on the opposing surfaces (faces F1 and F2) that have smaller areas in this way, it becomes easier to reduce the dimensions of the holding members 51 and 52 that hold the respective energy storage cells included in the cell connected bodies 10 and 20. However, without being limited to this, the holding members 51 and 52 may be provided on the second opposing surfaces instead of or in addition to the first opposing surfaces.

[0072] The holding members 51 and 52 may be fixed to the case 300 with an adhesive. However, not using this type of fixing method tends to increase the recyclability of the energy storage device. In the battery 100 (energy storage device) according to this embodiment, the holding members 51 and 52 hold the energy storage cells included in the cell assemblies 10 and 20. This makes it possible to omit the adhesive or to weaken the adhesive strength of the adhesive used. This improves the recyclability of the energy storage device. Even if the cell assemblies 10 and 20 move within the case 300 while being held by the holding members 51 and 52, the positional relationship between the energy storage cells does not change, and therefore the connection portions 2A to 2C are unlikely to be damaged.

[0073] Fig. 7 is a diagram showing a first modified example of the battery shown in Fig. 1. Fig. 8 is a cross-sectional view of the battery according to the first modified example, corresponding to Fig. 5. Fig. 9 is a cross-sectional view of the battery according to the first modified example, corresponding to Fig. 6.

[0074] As shown in FIG. 7, the battery 100A according to the first modification has a configuration basically similar to that of the battery 100 shown in FIG. 1. However, the battery 100A includes a case 300A instead of the case 300 (FIG. 1) and holding members 51A and 52A instead of the holding members 51 and 52 (FIG. 1). The case 300A includes a main body 310A and lids 320 and 330. The main body 310A is a cylindrical housing having openings on both end faces in the X direction (the end face on the +X side and the end face on the −X side) and accommodates the cell assemblies 10 and 20. The lid 320 shown in FIG. 7 is the same as the lid 320 shown in FIG. 1 and closes the opening on the +X side of the main body 310A. The lid 320 has a sealing hole 321. The lid 330 closes the opening on the −X side of the main body 310A. The lid 330 has a sealing hole 331. Each of the sealing holes 321, 331 has a sealing structure, for example, with a metal cap (outside the case) and a sealing member (inside the case). This sealing structure ensures airtightness inside the case 300A, and when the pressure inside the case 300A exceeds a predetermined level, gas is discharged to the outside of the case 300A through the sealing holes 321, 331.

[0075] As shown in FIGS. 7 to 9, the holding members 51A and 52A are holding members 51 and 52 (see FIG. 1) in which flow paths GL1 and GL2 are formed, respectively. Each of the flow paths GL1 and GL2 is a flow path for discharging gas generated from the energy storage cells. Specifically, the protrusions P14A and P24A shown in FIG. 9 are protrusions P14 and P24 (see FIG. 6) in which through-holes (for example, holes penetrating in the Z direction) are formed, connecting the spaces between two adjacent energy storage cells in the X direction to the flow paths GL1 and GL2. Each of these through-holes and the flow paths GL1 and GL2 guides gas generated from each energy storage cell included in the cell connected bodies 10 and 20 housed in the case 300A to the sealing hole 321 or 331. Each of the sealing holes 321 and 331 is configured to be able to discharge gas inside the case 300A to the outside of the case 300A. This configuration makes it easier to appropriately discharge gas generated from the energy storage cells.

[0076] The flow paths GL1 and GL2 form cavities inside the holding members 51A and 52A, respectively. In this way, each of the holding members 51A and 52A has a hollow structure. This makes it easier for the holding members 51A and 52A to absorb shocks applied to the case 300A from the outside. Each of the flow paths GL1 and GL2 may be formed by mechanical processing or chemically by etching or the like. A flow path may be formed in only one of the holding members 51 and 52 shown in FIG. 1.

[0077] FIG. 10 is a diagram showing a second modified example of the battery shown in FIG. 1. As shown in FIG. 10, the battery 100B according to the second modified example has a configuration basically similar to that of the battery 100A shown in FIG. 7. However, the battery 100B includes holding members 51B and 52B instead of holding members 51A and 52A (FIG. 7). The holding members 51B and 52B are the holding members 51 and 52 (see FIG. 1) having cavities R1 and R2, respectively, that do not function as gas discharge channels. Multiple cavities R1 are formed inside the holding member 51B. Multiple cavities R2 are formed inside the holding member 52B. As described above, each of the holding members 51B and 52B has a hollow structure. This allows the holding members 51B and 52B to more easily absorb external impacts applied to the case 300A. Each of the cavities R1 and R2 may be formed of a porous material. A cavity may be formed in only one of the holding members 51 and 52 shown in FIG. 1.

[0078] Fig. 11 is a diagram showing a third modified example of the battery shown in Fig. 1. As shown in Fig. 11, battery 100C according to the third modified example has a configuration in which holding member 52A (Fig. 7) is removed from battery 100A shown in Fig. 7. In battery 100C, a space (region R3) between the second surface of each storage cell included in cell connected bodies 10 and 20 and the inner surface (top surface) of case 300A functions as a gas discharge flow path (a flow path that guides gas generated from each storage cell to sealing hole 321 or 331).

[0079] FIG. 12 is a diagram illustrating a fourth modified example of the battery shown in FIG. 1. As shown in FIG. 12, a battery 100D according to the fourth modified example has basically the same configuration as the battery 100 shown in FIG. 1. However, the battery 100D includes holding members 51D and 52D instead of holding members 51 and 52 (FIG. 1). Tapered surfaces TP1 and TP2 are formed at the −X side ends of the holding members 51D and 52D, respectively. Each of the tapered surfaces TP1 and TP2 is a slope whose dimension in the Z direction decreases toward the end (−X side). The tapered surfaces formed at the ends of the holding members 51D and 52D make it easier to insert the cell assemblies 10 and 20, to which the holding members 51D and 52D are attached, into the main body 310 of the case 300 from the −X side end.

[0080] FIG. 13 is a diagram showing a fifth modified example of the battery shown in FIG. 1. As shown in FIG. 13, battery 100E according to the fifth modified example has basically the same configuration as battery 100A shown in FIG. 7. However, battery 100E includes holding members 51E and 52E instead of holding members 51A and 52A (FIG. 7). Tapered surfaces TP1 and TP2 are formed at the -X side ends of holding members 51E and 52E, respectively. Each of tapered surfaces TP1 and TP2 is a slope whose dimension in the Z direction decreases toward the first end (-X side). Tapered surfaces TP3 and TP4 are formed at the +X side ends of holding members 51E and 52E, respectively. Each of tapered surfaces TP3 and TP4 is a slope whose dimension in the Z direction decreases toward the second end (+X side). The tapered surfaces formed on both ends of each of the holding members 51E and 52E make it easier to insert the cell combinations 10 and 20 to which the holding members 51E and 52E are attached into the main body 310A of the case 300A.

[0081] FIG. 14 is a diagram showing a sixth modified example of the battery shown in FIG. 1. As shown in FIG. 14, a battery 100F according to the sixth modified example basically has the same cross-sectional structure as the battery 100 shown in FIG. 5. However, the battery 100F includes a holding member 52F instead of the holding member 52 (FIG. 5). The thermal conductivity of the holding member 52F is higher than that of the holding member 51. Specifically, the holding member 52F includes a metal, and the holding member 51 includes a resin. The holding member 52F may be formed entirely of a metal. The holding member 51 may be formed entirely of a resin. The holding member 52F is provided with protrusions P21F, P22F, and P23F having shapes similar to the protrusions P21, P22, and P23 shown in FIG. 5, respectively. Although not shown in FIG. 14, the holding member 52F further includes a protrusion corresponding to the protrusion P24 shown in FIG. 6. In battery 100F, the holding member 52F located on the +Z side of each storage cell has high thermal conductivity, making it easier to heat or cool each storage cell from outside the +Z side of each storage cell (for example, from a temperature control device 800 shown in Figure 22 described below).

[0082] In the battery 100F, the holding member 52F contains a metal, which increases the thermal conductivity of the holding member 52F. On the other hand, the holding member 52F containing a resin has excellent toughness and formability, and therefore easily holds the storage cells included in the cell connected bodies 10 and 20. The holding member 52F may include a main body made of metal and protrusions (the above-mentioned protrusions) made of resin. The holding member 52F may also have a structure in which particulate metal (e.g., metal filler) is dispersed in a binder (e.g., a resin binder).

[0083] FIG. 15 is a diagram showing a seventh modified example of the battery shown in FIG. 1. As shown in FIG. 15, a battery 100G according to the seventh modified example basically has the same cross-sectional structure as that of the battery 100F shown in FIG. 14. However, the battery 100G includes a holding member 52G instead of the holding member 52F (FIG. 14). The holding member 52G has a configuration in which the above-described protrusions of the holding member 52F are removed. The holding member 52G is a metal plate-like member (a flat-plate-shaped main body portion formed of metal) and has higher thermal conductivity than the resin holding member 51. This structure makes it easier to heat or cool each storage cell from the outside on the +Z side of each storage cell (for example, a temperature control device 800 shown in FIG. 22, which will be described later). The holding member 52G may have a structure in which particulate metal (for example, metal filler) is dispersed in a binder (for example, a resin binder).

[0084] FIG. 16 is a diagram illustrating an eighth modified example of the battery shown in FIG. 1. As shown in FIG. 16, the battery 100H according to the eighth modified example has basically the same configuration as the battery 100 shown in FIG. 1. However, in the battery 100H, the cell assembly 10, 20, and the holding members 51, 52 are integrated by winding a strip-shaped member 170. The member 170 is wound around each energy storage cell and the holding members 51 and 52 located on both sides of the cell assembly 10, 20, for example, by winding the member 170 around the X-axis as the axis of rotation. This reduces the likelihood of misalignment of the cell assembly 10, 20, and the holding members 51, 52. Furthermore, the cell assembly 10, 20, to which the holding members 51 and 52 are attached, can be easily inserted into the main body 310 of the case 300.

[0085] The member 170 may be a tape having adhesive properties on one or both sides. To improve recyclability, a tape that can be peeled off with a specific organic solvent may be used as the member 170. The member 170 is not limited to a strip-shaped tape. The member 170 may be formed in a linear shape like a string. For example, a resin member, a heat-shrinkable member, an elastic body (e.g., a rubber band), etc. may also be used as the member 170.

[0086] FIG. 17 is a diagram illustrating a ninth modification of the battery shown in FIG. 1. As shown in FIG. 17, a battery 100I according to the ninth modification has basically the same configuration as the battery 100 shown in FIG. 1. However, in the battery 100I, the cell assembled bodies 10 and 20 and the holding members 51 and 52 are integrated by winding a sheet-like member 180. The member 180 is wound around the entire cell assembled bodies 10 and 20 and the holding members 51 and 52, for example, by winding it around the Y axis. This reduces the likelihood of misalignment of the cell assembled bodies 10 and 20 and the holding members 51 and 52. This also makes it easier to insert the cell assembled bodies 10 and 20, to which the holding members 51 and 52 are attached, into the main body 310 of the case 300. The member 180 may be a resin film (e.g., a film containing vinyl chloride resin, polyvinylidene chloride, polyethylene, or polyolefin). The member 180 may also be a heat-shrinkable sheet.

[0087] Fig. 18 is a diagram showing a tenth modification of the battery shown in Fig. 1. As shown in Fig. 18, a battery 100J according to the tenth modification basically has the same cross-sectional structure as that of the battery 100 shown in Fig. 5. However, in the battery 100J, a gap is formed between a storage cell (e.g., storage cell 13) of the cell connected body 10 and a storage cell (e.g., storage cell 23) of the cell connected body 20 that are adjacent in the Y direction, and the holding members 51J and 52J have convex portions P13J and P23J formed to fit into the gap, instead of the convex portions P13 and P23 (Fig. 1), respectively. The convex portions P13J and P23J each have a dimension (dimension in the Y direction) corresponding to the spacing between the storage cells and function as a spacer. As shown in FIG. 18, for example, the protrusions P13J and P23J restrict movement of the power storage cell 13 to the −Y side and movement of the power storage cell 23 to the +Y side, thereby preventing the power storage cells 13 and 23 from coming too close to each other.

[0088] FIG. 19 is a diagram showing an eleventh modification of the battery shown in FIG. 1. As shown in FIG. 19, a battery 100K according to the eleventh modification has basically the same cross-sectional structure as the cross-sectional structure of the battery 100J shown in FIG. 18. However, in the battery 100K, each of the holding members 51K and 52K does not have a convex portion (the convex portions P13J and P23J shown in FIG. 18) that fits between a storage cell (e.g., storage cell 13) of the cell connected body 10 and a storage cell (e.g., storage cell 23) of the cell connected body 20 that are adjacent in the Y direction. Instead of these convex portions, a metal plate 190 is provided so as to fit between the storage cells. An end portion of the metal plate 190 on the −Z side is in contact with the holding member 51K, and an end portion of the metal plate 190 on the +Z side is in contact with the holding member 52K. The metal plate 190 is, for example, an aluminum plate. However, the present invention is not limited to this, and the metal plate 190 may be formed of a metal other than aluminum. The metal plate 190 may be, for example, a copper plate or a stainless steel plate.

[0089] According to the above configuration, for example, heat from each power storage cell is easily released to the outside of the case 300 through the metal plate 190. Furthermore, when each power storage cell is heated from the outside of the case 300 (for example, from a temperature adjustment device 800 shown in FIG. 22 described later), heat is easily transferred to each power storage cell through the metal plate 190. However, in a configuration in which sufficient thermal conductivity is ensured, at least one end of the metal plate 190 in the Z direction does not need to be in contact with the holding member.

[0090] It is not essential that a plurality of cell assemblies be housed in the case, and the number of cell assemblies housed in the case may be one. Fig. 20 is a diagram showing a twelfth modified example of the battery shown in Fig. 1. Fig. 21 is a cross-sectional view taken along line XXI-XXI in Fig. 20.

[0091] As shown in FIG. 20 , a battery 100L according to the twelfth modification includes a case 300B and a cell assembly 10 housed in the case 300B. The case 300B houses the cell assembly 10 but does not house the cell assembly 20. The case 300B includes a main body 310B and lids 320B and 330B. The main body 310B is a cylindrical housing having openings on both end faces in the X direction (the end face on the +X side and the end face on the −X side) and houses one cell assembly (the cell assembly 10). The lid 320B closes the opening on the +X side of the main body 310B. The lid 330B closes the opening on the −X side of the main body 310B. The lids 320B and 330B are provided with electrode tabs T3B and T4B, respectively. A connection terminal T1B is provided on the energy storage cell 11 located at one end (+X side) of the cell connected body 10 in the X direction, and a connection terminal T2B is provided on the energy storage cell 14 located at the other end (-X side) of the cell connected body 10 in the X direction. The electrode tabs T3B and T4B are electrically connected to the connection terminals T1B and T2B, respectively. The electrode tabs T3B and T4B function as, for example, a negative electrode tab and a positive electrode tab, respectively. However, without being limited to this, the polarities may be reversed, with the electrode tab T4B being the negative electrode tab and the electrode tab T3B being the positive electrode tab.

[0092] As shown in FIG. 21 , the holding member 51L is basically formed in a plate shape. However, the holding member 51L includes, in addition to a plate-shaped main body portion (first main body portion), convex portions P11L and P12L (first convex portions) that protrude from the main body portion toward the cell connected body 10. Each of the convex portions P11L and P12L protrudes toward the cell connected body 10 side (+Z side). The holding member 52L is also basically formed in a plate shape. However, in addition to a plate-shaped main body portion (second main body portion), the holding member 52L includes, in addition to a plate-shaped main body portion, convex portions P21L and P22L (second convex portions) that protrude from the main body portion toward the cell connected body 10. Each of the convex portions P21L and P22L protrudes toward the cell connected body 10 side (-Z side). Each of the holding members 51L and 52L includes an insulating material (e.g., resin) and has insulating properties. The holding members 51L and 52L hold each of the storage cells (including the storage cell 13 shown in FIG. 21) included in the cell connected body 10 so as to hold them in place. Specifically, the protrusions P11L and P12L are located at the ends (corners) of the first surfaces of the storage cells in the Y direction and function as claws. This prevents the storage cells from shifting in position. The protrusions P21L and P22L are located at the ends (corners) of the second surfaces of the storage cells in the Y direction and function as claws. This prevents the storage cells from shifting in position.

[0093] It is not essential that all of the energy storage cells included in the connected cell body be held by the holding member. For example, of the energy storage cells 11 to 14 included in the connected cell body 10, only the energy storage cells 12 and 13, i.e., only the center portion of the connected cell body 10 in the X direction, may be held by the holding member. Also, of the energy storage cells 11 to 14 included in the connected cell body 10, only the energy storage cells 11 and 14, i.e., only both end portions of the connected cell body 10 in the X direction, may be held by the holding member. The rectangular parallelepiped case that houses the connected cell body may be assembled by joining (for example, laser welding) six separately formed plates that constitute six faces (faces F1 to F6) to each other.

[0094] The above-described batteries 100, 100A to 100L and their variations can function as a power storage device on their own, but a plurality of such batteries may also be combined to form a module.

[0095] Fig. 22 is a diagram showing an example of a power storage module including multiple batteries. Fig. 22 shows the up-down direction, the front-rear direction, and the left-right direction, which are perpendicular to one another. "Down" corresponds to the vertical direction (the direction of gravity), and "up" corresponds to the opposite direction. The diagram showing the power storage module from above shows the internal structure of the power storage module 200.

[0096] The energy storage module 200 shown in FIG. 22 includes a plurality of batteries 100. In the energy storage module 200, the plurality of batteries 100 (see FIG. 1) are arranged so that the +Z side surface of each battery faces upward and the −Z side surface of each battery faces downward. However, for each of the plurality of batteries 100, it is possible to arbitrarily set whether the lid body 320 (the +X side surface) shown in FIGS. 1 and 2 faces left or right. For example, all of the batteries 100 in the energy storage module 200 may face the same direction. Alternatively, the energy storage module 200 may include both batteries 100 with the lid body 320 facing right and batteries 100 with the lid body 320 facing left. The plurality of batteries 100 may be electrically connected in series or in parallel. The energy storage module 200 functions as an energy storage device.

[0097] In the example shown in FIG. 22, a temperature adjustment device 800 is provided on the upper surface of the power storage module 200. The temperature adjustment device 800 is configured to adjust the temperature of each of the multiple batteries 100 included in the power storage module 200. The temperature adjustment device 800 may include at least one of a heater and a cooler. The temperature adjustment device 800 is controlled by a control device 900. The control device 900 includes, for example, a processor and a storage device, and is connected to each connector 323 ( FIG. 1 ) of the multiple batteries 100 included in the power storage module 200 via signal lines. The control device 900 receives signals (for example, sensor detection values) from the connector 323 of each battery and sends control commands to the temperature adjustment device 800. The control device 900 may control the temperature adjustment device 800 based on the state of each battery. Note that in the power storage module 200, another battery (any of the batteries 100A to 100L, or batteries with the various modifications described above) may be used instead of the battery 100. The temperature adjustment device 800 may also be provided on the lower surface of the power storage module 200.

[0098] The above-described batteries 100, 100A to 100L and their variations, as well as the power storage module 200, may be mounted on, for example, a mobile object. Examples of mobile objects include automobiles (electric vehicles, hybrid vehicles, etc.), vehicles other than automobiles (ships, airplanes, etc.), mobile machines (agricultural machines, construction machines, etc.), and unmanned mobile objects (automated guided vehicles, robots, etc.). However, the power storage device may be used for any purpose, and may be for stationary purposes.

[0099] FIG. 23 is a diagram showing an example of a vehicle equipped with the power storage module shown in FIG. 22. The vehicle 2000 shown in FIG. 23 includes a battery pack 1000. The battery pack 1000 includes a plurality of power storage modules 200 and functions as a power storage device. The battery pack 1000 may further include the temperature adjustment device 800 shown in FIG. 22. The battery pack 1000 may be installed either above or below the floor of the vehicle 2000. The vehicle 2000 is, for example, an electric vehicle configured to be able to run using power output from the battery pack 1000. The battery pack 1000 may supply power to a traction motor mounted on the vehicle 2000. In the battery pack 1000, the power storage modules 200 are electrically connected to each other via, for example, a bus bar. The battery pack 1000 may include 100 or more power storage cells.

[0100] The various features of the power storage device described above (the features described in the embodiments and modifications) may be implemented in any combination. The power storage device may be applied to devices other than vehicles.

[0101] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, not by the description of the above embodiments, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0102] 1, 11 to 14, 21 to 24: storage cells; 2, 2A to 2C: connection parts; 10, 20: cell assemblies; 51, 51A, 51B, 51D, 51E, 51J, 51K, 51L, 52, 52A, 52B, 52D, 52E, 52F, 52G, 52J, 52K, 52L: holding members; 100, 100A to 100L: batteries; 200: storage modules; 300, 300A, 300B: cases; 1000: battery packs; 2000: vehicles.

Claims

1. An electricity storage device, The power storage device includes a case and a cell assembly housed in the case, the cell assembly includes a plurality of energy storage cells and connection portions that electrically connect the energy storage cells to each other, The power storage device further includes one or more holding members that hold at least one of the plurality of power storage cells between the inner surface of the case and the cell assembly.

2. The energy storage device according to claim 1 , wherein the one or more holding members include a first holding member formed along the cell array and holding a first surface of each of the plurality of energy storage cells.

3. The power storage device according to claim 2 , wherein the first holding member includes a plate-shaped first main body portion and one or more first protrusions protruding from the first main body portion toward the cell connected body.

4. 3. The energy storage device according to claim 2, wherein the one or more holding members further include a second holding member formed along the cell assembly and holding a second surface of each of the plurality of energy storage cells opposite to the first surface.

5. The power storage device according to claim 4 , wherein the second holding member includes a plate-shaped second main body portion and one or more second protrusions protruding from the second main body portion toward the cell connected body.

6. The power storage device according to claim 4 , wherein at least one of the first holding member and the second holding member has a flow path formed therein for discharging gas generated from at least one of the plurality of power storage cells.

7. The power storage device according to claim 4 , wherein at least one of the first holding member and the second holding member has a hollow structure.

8. The power storage device according to claim 4 , wherein the second holding member has a higher thermal conductivity than the first holding member.

9. The power storage device according to claim 8 , wherein the second holding member includes a metal, and the first holding member includes a resin.

10. The power storage device according to claim 4 , wherein a tapered surface is formed at each end of the first holding member and the second holding member.

11. The power storage device according to claim 4 , wherein the cell connected body, the first holding member, and the second holding member are integrated by winding a wire-shaped, band-shaped, or sheet-shaped member.

12. The case has a rectangular parallelepiped outer shape, the case has four surfaces extending in the connecting direction of the cell assembly and two surfaces covering the ends of the cell assembly, the four surfaces include a first opposing surface that is a pair of opposing surfaces, and a second opposing surface that is an opposing surface having an area larger than that of the first opposing surfaces, The power storage device according to claim 1 , wherein the holding member is disposed on the first opposing surface.

13. A vehicle comprising the power storage device according to any one of claims 1 to 12.

Images