Electricity storage device

Abstract

A power storage device (10) is provided with: a power storage element unit (210) having a power storage element (211); an outer case (100) that has an outer case main body (110) that is open on one side in the first direction, and that houses the power storage element unit (210); and a first member (inner case upper wall (310)) disposed on one side of the power storage element unit (210) in the first direction, the outer case (100) having: an outer case bottom wall (111) disposed on the other side in the first direction; and outer case side walls (112) that face each other in a second direction that intersects the first direction. The first member is fixed to a second member (counterweight (400)) that is fixed to the outer case side walls (112), or the first member is fixed to the outer case side walls (112).

Description

Technical Field

[0001] The present invention relates to an electric storage device including an electric storage element unit having an electric storage element. Background Art

[0002] In the past, there is known a power storage device having a power storage element unit having a power storage element and an outer shell that accommodates the power storage element unit. Patent document 1 discloses a power supply device (power storage device) that accommodates a battery (power storage element) in a waterproof shell (outer shell), and fixes the battery in the waterproof shell by a fixing member. In Patent document 1, the battery is fixed to the bottom plate of the fixing member, and the peripheral edge of the top plate of the fixing member contacts the inner wall of the waterproof shell to suppress the top plate from moving in the horizontal direction, thereby suppressing the fixing member from moving in the horizontal direction in the waterproof shell.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2013-206816 Summary of the invention

[0006] Problems to be solved by the invention

[0007] In the above-mentioned conventional power storage device, it may not be easy to suppress the movement of the power storage element unit relative to the outer shell, and thus it is not easy to improve the vibration resistance or impact resistance. In the power supply device (power storage device) disclosed in Patent Document 1, it is necessary to make the periphery of the top plate of the fixing member contact the inner wall of the waterproof shell, so the dimensional accuracy of the top plate is required. In the case where the size of the top plate is large, the fixing member cannot be inserted into the waterproof shell, and in the case where the size of the top plate is small, the fixing member may move inside the waterproof shell. As described above, in the above-mentioned conventional power storage device, it may not be easy to improve the vibration resistance or impact resistance.

[0008] The present invention was made by the inventors of the present application with new attention paid to the above-mentioned problems, and an object of the present invention is to provide a power storage device capable of easily improving vibration resistance or impact resistance.

[0009] Solutions to Solve Problems

[0010] An electrical storage device according to one embodiment of the present invention comprises: an electrical storage element unit having an electrical storage element; an outer shell having an outer shell main body opened on one side in a first direction and accommodating the electrical storage element unit; and a first member arranged on one side of the electrical storage element unit in the first direction, the outer shell having: an outer shell bottom wall arranged on the other side in the first direction; and an outer shell side wall opposite in a second direction intersecting the first direction, the first member being fixed to a second member fixed to the outer shell side wall, or the first member being fixed to the outer shell side wall.

[0011] Effects of the Invention

[0012] According to the power storage device of the present invention, vibration resistance or impact resistance can be easily improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a perspective view showing the structure of the power storage device according to the embodiment.

[0014] Figure 2 It is a perspective view showing the internal structure of an outer casing of the power storage device according to the embodiment.

[0015] Figure 3 It is an exploded perspective view showing each component when the power storage unit included in the power storage device according to the embodiment is exploded.

[0016] Figure 4 It is a perspective view showing the structure of the electric storage element unit according to the embodiment.

[0017] Figure 5 It is a perspective view showing a structure in which the upper wall of the inner casing according to the embodiment is fixed to the counterweight.

[0018] Figure 6 This is a front view showing a structure in which an upper wall of an inner casing according to an embodiment is fixed to a counterweight.

[0019] Figure 7 This is a front view showing a structure in which an upper wall of an inner casing is fixed to a side wall of an outer casing according to a modification of the embodiment.

[0020] Figure 8 It is a front view showing a structure in which a first member according to another modification of the embodiment is fixed to a side wall of an outer casing. DETAILED DESCRIPTION

[0021] (1) An electric storage device according to one embodiment of the present invention comprises: an electric storage element unit having an electric storage element; an outer shell having an outer shell main body opened on one side in a first direction and accommodating the electric storage element unit; and a first member arranged on one side of the electric storage element unit in the first direction, the outer shell having: an outer shell bottom wall arranged on the other side in the first direction; and outer shell side walls opposed in a second direction intersecting the first direction, the first member being fixed to a second member fixed to the outer shell side wall, or the first member being fixed to the outer shell side wall.

[0022] Thus, in the power storage device, the power storage element unit is sandwiched by the first member and the bottom wall of the outer shell, and the first member is fixed to the second member fixed to the side wall of the outer shell or the side wall of the outer shell. Thus, the power storage element unit can be easily fixed relative to the outer shell, so that the movement of the power storage element unit relative to the outer shell can be restricted by a simple structure. Therefore, the vibration resistance or impact resistance of the power storage device can be improved.

[0023] (2) In the power storage device described in (1) above, the second member may be a weight.

[0024] Thus, by fixing the first member to the counterweight fixed to the side wall of the outer shell, the first member can be fixed to the side wall of the outer shell via the counterweight. Thus, the storage element unit can be easily fixed to the outer shell, and the movement of the storage element unit relative to the outer shell can be restricted by a simple structure.

[0025] (3) In the power storage device described in (1) or (2) above, the first member may include an extension portion extending toward the outer case side wall, and the extension portion may be fixed to the second member or the outer case side wall.

[0026] Thus, by providing the extension portion on the first member and fixing the extension portion to the second member or the outer shell side wall, the storage element unit can be easily fixed to the outer shell. Thus, the movement of the storage element unit relative to the outer shell can be restricted by a simple structure.

[0027] (4) In the power storage device described in any one of (1) to (3) above, the power storage device may further include an inner case housed in the outer case and housing and holding the power storage element unit, and the first member may be an upper wall of the inner case.

[0028] Thus, by providing the first member as the upper wall of the inner case housing the storage element unit, the storage element unit can be easily fixed to the outer case using the upper wall of the inner case. Thus, the movement of the storage element unit relative to the outer case can be restricted by a simple structure.

[0029] (5) In the power storage device described in (4) above, the inner case may include three or more walls that are separate from each other.

[0030] Thus, by assembling the inner case from three or more walls that are separately formed, each wall can be easily arranged on the outer surface of the storage element unit. Since each wall can be arranged on the outer surface of the storage element unit, it is easy to restrict the movement of the storage element unit.

[0031] (6) In the power storage device described in (4) or (5), the power storage element unit may include a side member disposed on a side of the power storage element, and the side member may be in contact with an inner surface of the inner case.

[0032] Thus, the side members of the electric storage element unit are brought into contact with the inner surface of the inner case, thereby restricting the movement of the electric storage element unit in the inner case.

[0033] Hereinafter, the power storage device involved in the embodiments of the present invention (including its modified examples) will be described with reference to the drawings. The embodiments described below all represent general or specific examples. The numerical values, shapes, materials, components, configuration positions and connection methods of components, manufacturing processes, and the order of manufacturing processes shown in the following embodiments are examples and are not intended to limit the present invention. In each figure, dimensions, etc. are not strictly illustrated. In each figure, the same or identical components are marked with the same figure marks.

[0034] In the following description and drawings, the opposing direction of a pair of short side walls of the outer shell of the storage device, the arrangement direction of a pair of external terminals of the storage element unit, the opposing direction of a pair of side members of the storage element unit, the opposing direction of the long side of the storage element and the side member of the storage element unit, the arrangement direction (opposing direction) of the side member of the storage element unit and the short side wall of the inner shell, or the opposing direction of a pair of long side faces of the storage element is defined as the X-axis direction. The opposing direction of the long side walls of the outer shell of the storage device, the protruding direction of the external terminals of the storage element unit, the opposing direction of a pair of short side faces of the container of the storage element, or the arrangement direction of a pair of electrode terminals of the storage element is defined as the Y-axis direction. The arrangement direction of the opening of the main body of the outer shell of the storage device and the bottom wall of the outer shell, the arrangement direction of the storage element unit and the bottom wall of the outer shell, the arrangement direction (opposing direction) of the upper wall of the inner shell and the bottom wall of the inner shell, the arrangement direction of the main body and the cover of the container of the storage element, the protruding direction of the electrode terminal of the storage element, or the up-down direction is defined as the Z-axis direction. The X-axis direction, the Y-axis direction, and the Z-axis direction are directions that intersect with each other (in the present embodiment, are orthogonal).

[0035] In the following description, the so-called positive direction of the X-axis indicates the direction of the arrow of the X-axis, and the so-called negative direction of the X-axis indicates the direction opposite to the positive direction of the X-axis. When it is only referred to as the X-axis direction, it indicates the two directions or any one direction of the positive direction of the X-axis and the negative direction of the X-axis. The same is true for the Y-axis direction and the Z-axis direction. In the following, the Z-axis direction is sometimes referred to as the first direction (the positive direction of the Z-axis is referred to as one side in the first direction, and the negative direction of the Z-axis is referred to as the other side in the first direction), the X-axis direction is referred to as the second direction, and the Y-axis direction is referred to as the third direction. The X-axis direction is sometimes described as the left and right direction. Expressions such as parallel and orthogonal that indicate relative directions or postures also include situations where the directions or postures are not strictly speaking. The so-called parallelism of two directions not only means that the two directions are completely parallel, but also means that they are substantially parallel, that is, including a difference of about a few percent. In the following description, when expressed as "insulation", it means "electrical insulation".

[0036] (Implementation Method)

[0037] [1 Overall Description of Power Storage Device 10]

[0038] First, the overall description of the power storage device 10 in the present embodiment will be given. Figure 1 is a perspective view showing the structure of the power storage device 10 according to the present embodiment. Figure 1 , a state in which the outer case cover 120 is removed from the outer case main body 110 of the outer case 100 included in the power storage device 10 is shown. Figure 2 1 is a perspective view showing the internal structure of the outer case 100 of the power storage device 10 according to the present embodiment. Figure 2 , a state is shown in which the power storage cell 20 inside the outer case 100 provided in the power storage device 10 is taken out from the outer case main body 110 . Figure 3 It is an exploded perspective view showing each component when the power storage unit 20 included in the power storage device 10 according to the present embodiment is exploded.

[0039] The power storage device 10 is a device that can charge electricity from the outside and discharge electricity to the outside. In the present embodiment, it has a rectangular parallelepiped shape. The power storage device 10 is used for power storage purposes or power supply purposes. The power storage device 10 is used as a battery for driving or starting the engine of a mobile body such as a car, a motorcycle, a forklift, a jet ski, a ship, a snowmobile, an agricultural machine, a construction machine, or a railway vehicle for an electric railway. As the above-mentioned car, an electric car (EV), a hybrid electric car (HEV), a plug-in hybrid electric car (PHEV) and a fossil fuel (gasoline, light oil, liquefied natural gas, etc.) car are exemplified. As the above-mentioned railway vehicle for the electric railway, a tram, a monorail, a linear motorcar, and a hybrid electric car with both a diesel engine and an electric motor are exemplified. The power storage device 10 can also be used as a battery for fixed installation for home or business use.

[0040] like Figure 1~Figure 3 As shown, the power storage device 10 includes an outer case 100, a power storage cell 20, and a weight 400. The power storage cell 20 includes a power storage cell group 200 composed of a plurality of power storage element cells 210 and an inner case 300. In addition to the above-mentioned structure, the power storage device 10 also includes a positive terminal and a negative terminal of the power storage device 10, a conductive member (wire, bus bar, etc.) connecting the power storage element cells 210 to each other or the power storage element cells 210 to the main terminal, and a circuit substrate for monitoring or controlling the state (voltage, temperature, charge and discharge state, etc.) of the power storage element cells 210, a relay, a fuse, a current sensor, and a connector and other electrical components, but the drawings and detailed descriptions are omitted.

[0041] The outer shell 100 is a shell that accommodates the storage element unit 210. The outer shell 100 is a rectangular (box-shaped) container (outer box) that constitutes the outer shell (external body, shell, shell) of the storage device 10. The outer shell 100 is arranged on the outer side of the storage unit 20 (storage element unit group 200, inner shell 300) and the counterweight 400, etc., and fixes them at a predetermined position to protect them from impact, etc. The outer shell 100 is a metal shell formed of a metal member such as aluminum, aluminum alloy, stainless steel, iron, plated steel plate, etc. The outer shell 100 can also be formed of an insulating member such as any resin material that can be used for the cover member 216 of the storage element unit 210 described later.

[0042] like Figure 1As shown, the outer shell 100 includes an outer shell body 110 constituting the main body of the outer shell 100 and an outer shell cover 120 constituting the cover of the outer shell 100. The outer shell body 110 is a bottomed rectangular cylindrical container opened in the positive direction of the Z axis (one side in the first direction), and accommodates the storage cell 20 (storage element cell group 200, inner shell 300) and the counterweight 400, etc., and fixes them at a predetermined position.

[0043] Specifically, if Figure 2 As shown, the outer shell body 110 is formed with a rectangular opening 110a in the positive direction of the Z axis (one side in the first direction), and an outer shell bottom wall 111 is formed as the bottom wall of the outer shell in the up-down direction in the negative direction of the Z axis (the other side in the first direction). The outer shell bottom wall 111 is formed in a flat plate and rectangular shape. The outer shell body 110 has a pair of flat plate and rectangular short side walls, namely, outer shell side walls 112, on both sides of the X axis direction, and a pair of flat plate and rectangular long side walls, namely, outer shell side walls 113, on both sides of the Y axis direction. The outer shell side walls 112 are walls that are opposite (orthogonal) in the X axis direction (a second direction intersecting the first direction), and are arranged at the end of the outer shell body 110 in the X axis direction (the second direction). The outer shell side walls 113 are walls that are opposite (orthogonal) in the Y axis direction (a third direction intersecting the first direction and the second direction), and are arranged at the end of the outer shell body 110 in the Y axis direction (the third direction). The pair of outer casing side walls 112 are opposed to each other in the X-axis direction (a second direction intersecting the first direction) and the pair of outer casing side walls 113 are opposed to each other in the Y-axis direction (a third direction intersecting the first direction and the second direction).

[0044] The outer shell cover 120 is a plate-shaped and rectangular cover that blocks the opening 110a of the outer shell body 110. The outer shell body 110 and the outer shell cover 120 are joined by screw fastening based on bolts, etc. As a result, the outer shell 100 becomes a structure in which the interior is sealed. The outer shell body 110 and the outer shell cover 120 can also be joined by welding or bonding, etc. The outer shell body 110 and the outer shell cover 120 can be formed by components of the same material or by components of different materials. According to the structure (quantity, size, shape, etc.) of the contents of the outer shell 100, the outer shell body 110 (the outer shell bottom wall 111, the outer shell side walls 112, 113) and the outer shell cover 120 can be any shape. In this case, the outer shell side wall 112 can also be a long side wall, and the outer shell side wall 113 can be a short side wall.

[0045] like Figure 3As shown, the storage element unit group 200 has a plurality of storage element units 210. In the present embodiment, the storage element unit group 200 is composed of six storage element units 210 arranged in two layers along the Z-axis direction, which are arranged in three storage element units 210 arranged in the X-axis direction. The number of storage element units 210 included in the storage element unit group 200 is not particularly limited, and several storage element units 210 may be arranged in the Z-axis direction, several storage element units 210 may be arranged in the X-axis direction, or multiple storage element units 210 may be arranged in the Y-axis direction. The storage element unit group 200 may also have only one storage element unit 210. In the present embodiment, the storage element units 210 arranged in the Z-axis direction are connected in series, and the storage element units 210 arranged in the X-axis direction are connected in parallel, but any storage element unit 210 may be connected in series or in parallel. A detailed description of the structure of the storage element unit 210 will be described later.

[0046] The inner housing 300 is a housing for housing the electric storage element unit 210. The inner housing 300 is a container (inner box) of a substantially rectangular parallelepiped shape (box shape) constituting the housing (frame) inside the electric storage device 10. The inner housing 300 is arranged outside the electric storage element unit group 200, and houses and holds the electric storage element unit group 200 (electric storage element unit 210) to protect it from impact, etc. The inner housing 300 is a metal housing formed of a member made of metal such as aluminum, aluminum alloy, stainless steel, iron, plated steel plate, etc. In the present embodiment, the inner housing 300 may be formed of a member of the same material as the outer housing 100, or may be formed of a member of a different material from the outer housing 100. The inner housing 300 may also be formed of an insulating member such as any resin material that can be used for the cover member 216 of the electric storage element unit 210 described later. In the present embodiment, the inner housing 300 housing the electric storage element unit 210 is housed in the outer housing 100.

[0047] like Figure 2 as well as Figure 3 As shown in the figure, the inner housing 300 has an inner housing upper wall 310 as an upper wall in the up-down direction of the inner housing 300 and an inner housing bottom wall 320 as a bottom wall in the up-down direction of the inner housing 300. The inner housing 300 has inner housing side walls 330 to 360 constituting four side walls in the X-axis direction or the Y-axis direction of the inner housing 300. In this embodiment, the inner housing upper wall 310, the inner housing bottom wall 320, and the inner housing side walls 330 to 360 are all separately constituted. That is, the inner housing 300 has six walls that are separately constituted.

[0048] The inner housing upper wall 310 is a flat and rectangular upper wall parallel to the XY plane (opposite in the Z-axis direction (orthogonal to the Z-axis direction)) arranged in the positive direction of the Z-axis (one side in the first direction) of the storage element unit group 200. The inner housing upper wall 310 is arranged between the storage element unit group 200 and the outer housing cover 120 in the Z-axis direction. The inner housing upper wall 310 is joined to the ends of the inner housing side walls 330, 340 and 360 in the positive direction of the Z-axis by screws 313. In the present embodiment, the inner housing upper wall 310 is arranged in the positive direction of the Z-axis of the inner housing side walls 330, 340 and 360, and is joined to the ends of the inner housing side walls 330, 340 and 360 in the positive direction of the Z-axis in the Z-axis direction. Electrical components such as circuit boards, relays, fuses, current sensors, and connectors that monitor or control the state (voltage, temperature, charge and discharge state, etc.) of the power storage element unit 210 may be disposed on the upper surface of the inner case upper wall 310 .

[0049] In the present embodiment, the inner housing upper wall 310 is fixed to the counterweight 400. Specifically, the inner housing upper wall 310 has extensions 311 extending to both sides in the X-axis direction at both ends thereof, and the extensions 311 are fixed to the counterweight 400. A detailed description of the structure in which the inner housing upper wall 310 is fixed to the counterweight 400 will be described later. The inner housing upper wall 310 is an example of a "first member". The first member (the inner housing upper wall 310) is a part of the inner housing 300 and is joined to other parts of the inner housing 300 (the inner housing side walls 330, 340, 360).

[0050] The inner housing bottom wall 320 is a flat and rectangular bottom wall arranged in the negative Z-axis direction (the other side in the first direction) of the storage element unit group 200 and parallel to the XY plane (opposite in the Z-axis direction (orthogonal to the Z-axis direction)). The inner housing bottom wall 320 is arranged between the storage element unit group 200 and the outer housing bottom wall 111 in the Z-axis direction. The inner housing bottom wall 320 is joined to the negative Z-axis end of the inner housing side walls 330 to 360 by threaded fastening based on bolts, etc. In the present embodiment, the inner housing bottom wall 320 is arranged between the inner housing side walls 330 and 340 in the X-axis direction, and is joined to the negative Z-axis end of the inner housing side walls 330 and 340 in the X-axis direction. The inner housing bottom wall 320 is arranged between the inner housing side walls 350 and 360 in the Y-axis direction, and is joined to the negative Z-axis end of the inner housing side walls 350 and 360 in the Y-axis direction. The inner housing bottom wall 320 may also be bonded (fixed) to the outer housing bottom wall 111 by adhesive or double-sided tape.

[0051] The inner housing side walls 330 and 340 are short side walls of a flat plate shape and a rectangular shape, which are parallel to the YZ plane (opposite in the X-axis direction (orthogonal to the X-axis direction)) and are arranged on both sides in the X-axis direction (second direction) of the storage element unit group 200. The inner housing side wall 330 is arranged in the positive direction of the X-axis of the storage element unit group 200, and the inner housing side wall 340 is arranged in the negative direction of the X-axis of the storage element unit group 200. The inner housing side walls 330 and 340 are arranged between the storage element unit group 200 and the outer housing side wall 112 (between the storage element unit group 200 and the counterweight 400) in the X-axis direction. The inner housing side walls 330 and 340 are joined to the X-axis direction ends of the inner housing upper wall 310, the inner housing bottom wall 320, and the inner housing side walls 350 and 360 by screw fastening based on bolts or the like. In this embodiment, the inner housing side walls 330 and 340 are arranged outside the inner housing bottom wall 320 and the inner housing side wall 360 in the X-axis direction, and are joined to both ends of the inner housing bottom wall 320 and the inner housing side wall 360 in the X-axis direction. Specifically, bolts ( Figure 3 The bolts 331 and 341, etc.) and the threaded holes ( Figure 3 Thus, the storage element unit group 200 can be firmly restrained by the inner case side walls 330 and 340. It is also possible to easily accommodate the storage element unit group 200 in the inner case 300.

[0052] The inner housing side walls 350 and 360 are long flat rectangular side walls arranged on both sides in the Y-axis direction (third direction) of the storage element unit group 200 and parallel to the XZ plane (opposite in the Y-axis direction (orthogonal to the Y-axis direction)). The inner housing side wall 350 is arranged in the negative direction of the Y-axis of the storage element unit group 200, and the inner housing side wall 360 is arranged in the positive direction of the Y-axis of the storage element unit group 200. The inner housing side walls 350 and 360 are arranged between the storage element unit group 200 and the outer housing side wall 113 in the Y-axis direction. The inner housing side wall 350 is joined to the negative end of the Y-axis of the inner housing bottom wall 320 and the inner housing side walls 330 and 340 by screw fastening with bolts or the like. In the present embodiment, the inner housing side wall 350 is arranged in the negative direction of the Y axis of the inner housing bottom wall 320, the inner housing side walls 330 and 340, and is joined to the negative end of the Y axis in the Y axis direction of the inner housing bottom wall 320, the inner housing side walls 330 and 340. The inner housing side wall 360 is joined to the positive end of the Y axis in the inner housing upper wall 310, the inner housing bottom wall 320, the inner housing side walls 330 and 340 by screw fastening with bolts or the like. In the present embodiment, the inner housing side wall 360 is arranged in the positive direction of the Y axis of the inner housing bottom wall 320, and is joined to the positive end of the Y axis in the Y axis direction of the inner housing bottom wall 320.

[0053] The inner case 300 restricts the movement of the storage element unit group 200 by making at least one of the inner case upper wall 310, the inner case bottom wall 320, and the inner case side walls 330 to 360 contact the storage element unit group 200. In the present embodiment, the inner case upper wall 310, the inner case bottom wall 320, the inner case side walls 330, 340, and 360 contact the storage element unit group 200, but the inner case side wall 350 may also contact the storage element unit group 200. Alternatively, at least one of the inner case upper wall 310, the inner case bottom wall 320, and the inner case side walls 330 to 360 may have a plate-like member such as a rubber plate or a resin member for tolerance absorption, vibration suppression, or anti-slip on the inner surface, and contact the storage element unit group 200 through the plate-like member.

[0054] The walls of the inner shell upper wall 310, the inner shell bottom wall 320, and the inner shell side walls 330~360 can also be joined to each other by welding or bonding. For the inner shell upper wall 310, the inner shell bottom wall 320, and the inner shell side walls 330~360, all walls can be formed by components of the same material, or any wall can be formed by components of different materials. Depending on the size and shape of the storage element unit group 200, the inner shell upper wall 310, the inner shell bottom wall 320, and the inner shell side walls 330~360 can be walls of any shape. In this case, the inner shell side walls 330 and 340 can also be long side walls, and the inner shell side walls 350 and 360 can be short side walls.

[0055] The counterweight 400 is a weight disposed inside the outer case 100 and outside the inner case 300. The counterweight 400 is a counterweight (balance weight) for adjusting the weight of the power storage device 10. In the present embodiment, the counterweight 400 has a rectangular parallelepiped shape that is flat in the X-axis direction (see Figure 5 ). The counterweight 400 is arranged in a state of being opposed to the outer shell side wall 112 of the outer shell body 110 of the outer shell 100 and in contact with the outer shell side wall 112. In the present embodiment, the counterweight 400 is joined to (fixed to) the outer shell side wall 112 by welding (spot welding, etc.). The counterweight 400 may also be joined to (fixed to) the outer shell side wall 112 by bonding, welding, bolting, or riveting with an adhesive or double-sided tape, etc. In the present embodiment, two counterweights 400 are arranged on both sides of the storage cell 20 (storage element cell group 200, inner shell 300) in the X-axis direction (see Figure 5 as well as Figure 6 Specifically, two counterweights 400 are disposed between the inner housing side wall 330 and the outer housing side wall 112 in the positive direction of the X axis and between the inner housing side wall 340 and the outer housing side wall 112 in the negative direction of the X axis.

[0056] The weight of the counterweight 400 is appropriately determined to be the weight required to adjust the weight of the power storage device 10. In the present embodiment, the weight of one counterweight 400 is about 50 to 60 kg. The total weight of all (two in the present embodiment) counterweights 400 provided by the power storage device 10 is preferably 1 / 5 or more of the total weight of the power storage device 10, more preferably 1 / 4 or more, and further preferably 1 / 3 or more. The material of the counterweight 400 is not particularly limited, and can be formed by any metal member that can be used for the outer shell 100 and the inner shell 300, such as aluminum, aluminum alloy, stainless steel, and iron. In the present embodiment, the two counterweights 400 are formed by members of the same material as the outer shell 100 and the inner shell 300, but can also be formed by members of different materials from the outer shell 100 and the inner shell 300, and the two counterweights 400 can also be formed by members of different materials. The counterweight 400 is an example of a "second member".

[0057] [2 Description of the power storage element unit 210]

[0058] Next, the structure of the power storage element unit 210 will be described in detail. Figure 4 2 is a perspective view showing the structure of the power storage element unit 210 according to the present embodiment. Figure 4 In Figure 3 One of the storage element cells 210 shown in FIG. 1 is enlarged, and the storage element 211 and the external terminal 215 located inside are shown by dotted lines. All of the plurality of storage element cells 210 provided in the storage device 10 (storage cell 20, storage element cell group 200) have the same structure. Figure 4 , one power storage element unit 210 is shown, and the structure of one power storage element unit 210 will be described in detail below.

[0059] The power storage element unit 210 is a substantially rectangular parallelepiped battery module (battery pack) that can charge electricity from the outside and discharge electricity to the outside. Figure 4 As shown, the storage element unit 210 includes a plurality of storage elements 211, a pair of end plates 212, a pair of side plates 213, an outer casing 214, a pair of (positive and negative) external terminals 215, and a pair of (positive and negative) cover members 216. In addition to the above-mentioned structure, the storage element unit 210 further includes a spacer disposed between the storage elements 211, a bus bar connecting the electrode terminals 211b of the plurality of storage elements 211 to each other, and a bus bar frame for positioning the bus bar, etc., but illustration and detailed description are omitted.

[0060] The storage element 211 is a secondary battery (single cell) that can charge and discharge electricity, more specifically, a non-aqueous electrolyte secondary battery such as a lithium ion secondary battery. In the present embodiment, a plurality of storage elements 211 are arranged along the X-axis direction and the Y-axis direction, but the arrangement direction and number of the storage elements 211 are not particularly limited, and it can also be configured to have only one storage element 211. In the present embodiment, when the storage element 211 is arranged in such a way that the direction in which a pair of electrode terminals 211b are arranged becomes the Y-axis direction, the storage element 211 is in a rectangular parallelepiped shape (square) flat in the X-axis direction, and has a long side and a short side. In the storage element 211, the X-axis direction becomes the thickness direction of the storage element 211. The shape of the storage element 211 is not limited to a rectangular parallelepiped shape, and may also be a polygonal prism shape, a cylindrical shape, a long cylindrical shape, an elliptical cylindrical shape, etc. other than a rectangular parallelepiped shape. The storage element 211 is not limited to a non-aqueous electrolyte secondary battery, and may be a secondary battery other than a non-aqueous electrolyte secondary battery, or may be a capacitor. The power storage element 211 may not be a secondary battery but a primary battery that allows the user to use the stored electricity even if the user does not charge the battery. The power storage element 211 may be a battery using a solid electrolyte. The power storage element 211 may be a pouch-type power storage element.

[0061] The storage element 211 has: a container 211a having a long side and a short side and a pair of electrode terminals 211b (positive and negative electrodes). An electrode body, a pair of current collectors (positive and negative electrodes), and an electrolyte (non-aqueous electrolyte) are housed inside the container 211a, but their illustrations and detailed descriptions are omitted. The container 211a has a container body with an opening and a cover that closes the opening of the container body, and the electrode terminal 211b is arranged in a state of protruding from the cover in the positive direction of the Z axis. The electrode terminal 211b is electrically connected to the positive electrode plate and the negative electrode plate of the electrode body via a conductive current collector. The electrode body is a storage element (power generation element) formed by stacking positive electrode plates, negative electrode plates, and separators.

[0062] The end plates are components arranged at both ends of the arrangement when a plurality of storage elements are arranged in such a manner that the long sides of each storage element are opposed to each other. The side plates are components connected to the end plates at both ends. A pair of end plates 212 is sandwiched from both sides in the arrangement direction (X-axis direction) when a plurality of storage elements 211 are arranged in such a manner that the long sides of each storage element 211 are opposed to each other. The pair of end plates 212 is a restraining component that presses (restrains) the plurality of storage elements 211 from both sides in the arrangement direction (X-axis direction). A pair of side plates 213 is connected to the pair of end plates that restrain the plurality of storage elements 211. From the perspective of ensuring strength, etc., the end plates 212 and the side plates 213 are formed of metal components such as steel or stainless steel, but the material thereof is not particularly limited, and it may be formed of a component with high strength and insulation, or the metal component may be subjected to insulation treatment.

[0063] The end plate 212 is a plate-shaped and rectangular member arranged in the X-axis direction of the storage element 211. A pair of end plates 212 are arranged on both sides of the multiple storage elements 211 in the X-axis direction, and the multiple storage elements 211 are sandwiched from both sides in the X-axis direction (the arrangement direction of the storage elements 211) to be retained. The end plate 212 is arranged opposite to the long side of the storage element 211. The end plate 212 may not be a plate-shaped member, but a flat block-shaped member. The end plate 212 is an example of a "side member" arranged on the side of the storage element 211. In other words, the "side member" is a member arranged on the side of the storage element 211 and arranged on the surface intersecting with the surface of the storage element unit 210 on which the external terminal 215 is arranged.

[0064] When the storage element unit 210 (storage element unit group 200 ) is arranged in the inner case 300 , the end plate 212 (side member) of the storage element unit 210 located at the end in the X-axis direction is in contact with the inner surface of the inner case 300 (see Figure 6 ). That is, the end plates 212 of the storage element unit group 200 located at both ends in the X-axis direction are in contact (surface contact) with the inner surfaces of the inner shell side walls 330 and 340. When the inner shell side wall 330 or 340 has a plate-like member on the inner surface as described above, the end plate 212 is in contact (surface contact) with the plate-like member. When other members (plate-like members) are sandwiched between the end plate 212 and the inner surface of the inner shell 300, the end plate 212 is indirectly in contact with the inner surface of the inner shell 300 via the other members (plate-like members). Two storage element units 210 adjacent to each other in the X-axis direction are arranged in a state where the end plates 212 facing each other in the X-axis direction are in contact (surface contact) with each other (overlapping in the X-axis direction). Similarly, two storage element units 210 adjacent to each other in the Z-axis direction are arranged in a state where the end plates 212 facing each other in the Z-axis direction are in contact with each other (overlapping in the Z-axis direction). When another member is interposed between the end plates 212 , the end plates 212 are in indirect contact with each other via the other member.

[0065] As described above, the outer shape of the storage element unit 210 has no part protruding from the end plate 212 except for the surface in the negative direction of the Y axis. For the end plate 212, the outer surface in the X axis direction is flat (plane), and the end surfaces on both sides of the Y axis direction and both sides of the Z axis direction are also all flat (plane). Therefore, the storage element units 210 can be arranged in a manner that the storage element units 210 are in contact with each other in the X axis direction without shaking, so that they can be directly stacked in the Z axis direction. The storage element unit 210 can also be arranged in a manner that the storage element unit 210 is in contact with the inner surface of the inner case 300 without shaking.

[0066] The side plate 213 is a plate-shaped and rectangular member arranged in the Y-axis direction of the storage element 211. That is, a pair of side plates 213 are arranged on both sides of the multiple storage elements 211 in the Y-axis direction. The side plates 213 are arranged opposite to the short sides of the storage elements 211. The side plates 213 constrain the multiple storage elements 211 by mounting the two ends in the X-axis direction on the ends in the Y-axis direction of a pair of end plates 212 to connect the pair of end plates 212. That is, the side plate 213 extends in the X-axis direction in a manner spanning across the multiple storage elements 211, and applies a restraining force in the X-axis direction to the multiple storage elements 211. In the present embodiment, the side plate 213 is joined to the end plate 212 (fixed to the end plate 212) by bolts and nuts (not shown), but it can also be joined (fixed) by welding or bonding. The side plate 213 may not be a plate-shaped member, but a long strip-shaped member, etc.

[0067] The outer casing 214 is a member covering the plurality of storage elements 211 and the like in the positive direction of the Z axis, and protects the plurality of storage elements 211 and the like from external impacts, etc. The outer casing 214 is mounted and fixed to a pair of side plates 213. In the present embodiment, the outer casing 214 is a metal member, but may also be a resin member.

[0068] The external terminal 215 is electrically connected to the electrode terminal 211b of the storage element 211, and is an external terminal for charging electricity from the outside and discharging electricity to the outside. In other words, the external terminal 215 is a terminal member different from the electrode terminal 211b of the storage element 211. The external terminal 215 is formed of a conductive member made of a metal such as aluminum, aluminum alloy, copper, copper alloy, nickel, or a combination thereof, or a conductive member other than a metal. The external terminal 215 is arranged at the end of the storage element unit 210 in the Y-axis direction. In this embodiment, a pair of (positive and negative) external terminals 215 arranged in the X-axis direction are arranged at the end of the storage element unit 210 in the Y-axis negative direction, the end in the Z-axis positive direction, and the two ends in the X-axis direction. The external terminal 215 is arranged in a state of protruding from the main body of the storage element unit 210 (the part where the storage element 211 is arranged) in the Y-axis negative direction. Specifically, the external terminal 215 protrudes in the negative Y-axis direction from the negative Y-axis surface of the side plate 213 and the negative Y-axis surface of the exterior member 214 .

[0069] The cover member 216 is a cover member of the external terminal 215 that is configured to cover the external terminal 215 to insulate and protect the external terminal 215. The cover member 216 is formed of insulating members 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 their composite materials. The cover member 216 can also be formed of a metal with an insulating coating. The cover member 216 protects the external terminal 215 and prevents the external terminal 215 from contacting with external metal members.

[0070] [3 Description of the structure of fixing the inner casing upper wall 310 to the counterweight 400]

[0071] Next, the structure in which the inner casing upper wall 310 (first member) is fixed to the counterweight 400 (second member) will be described in detail. Figure 5 It is a perspective view showing a structure in which the inner casing upper wall 310 according to the present embodiment is fixed to the counterweight 400 . Figure 5 FIG. 2 shows a state before the inner case upper wall 310 (electric storage unit 20) is fixed to the counterweight 400. When the inner case upper wall 310 (electric storage unit 20) is fixed to the counterweight 400, the counterweight 400 is fixed to the outer case side wall 112 of the outer case 100. Figure 5 In the figure, the outer shell 100 is omitted for convenience of explanation. Figure 6 It is a front view showing a structure in which the inner casing upper wall 310 according to the present embodiment is fixed to the counterweight 400 . Figure 6 The state after the inner case upper wall 310 (electric storage unit 20 ) is fixed to the counterweight 400 is shown. Figure 6 The figure is a view of the structure in which the outer case side wall 113 and the inner case side wall 350 in the negative direction of the Y axis are removed from the outer case body 110 in a state where the storage cells 20 (storage element cell group 200 , inner case 300 ) and the weight 400 are housed for convenience of explanation, as viewed from the negative direction of the Y axis.

[0072] The inner housing upper wall 310 (first component) is fixed to the counterweight 400 (second component) fixed to the outer housing side wall 112. Specifically, the inner housing upper wall 310 (first component) has an extension portion 311 extending toward the outer housing side wall 112, and the extension portion 311 is fixed to the counterweight 400 (second component) or the outer housing side wall 112. In this embodiment, Figure 5 as well as Figure 6As shown, the inner housing upper wall 310 (first component) is fixed to the counterweight 400 (second component) fixed to the outer housing side wall 112. That is, the extension portion 311 of the inner housing upper wall 310 (first component) extending toward the outer housing side wall 112 is fixed to the counterweight 400 (second component).

[0073] The extension portion 311 is disposed at both ends of the inner case upper wall 310 in the X-axis direction. The extension portion 311 is a plate-shaped portion that is longer in the Y-axis direction. The extension portion 311 is a portion that extends from the side wall of the inner case 300 in the X-axis direction. The extension portion 311 extends beyond the end of the storage element unit group 200 when viewed from the Y-axis direction. The extension portion 311 in the positive direction of the X-axis extends from the inner case side wall 330 in the positive direction of the X-axis, and the extension portion 311 in the negative direction of the X-axis extends from the inner case side wall 340 in the negative direction of the X-axis.

[0074] The extension portion 311 is provided with a fixing member 311a for fixing to the counterweight 400. In the present embodiment, three fixing members 311a arranged in the Y-axis direction are arranged in one extension portion 311. On the counterweight 400, three fixed portions 400a arranged in the Y-axis direction are formed at positions corresponding to the three fixing members 311a at the end portion in the positive direction of the Z-axis. In the present embodiment, the fixing member 311a is a bolt extending in the negative direction of the Z-axis and having an external threaded portion, and the fixed portion 400a is a threaded hole recessed in the negative direction of the Z-axis and formed with an internal threaded portion. The fixing member 311a is inserted into the fixed portion 400a for connection (combination), so that the extension portion 311 is fixed to the counterweight 400. Thus, the extension portion 311 of the inner shell upper wall 310 is overlapped and arranged in the positive direction of the Z-axis of the counterweight 400, and the inner shell upper wall 310 is fixed to the counterweight 400 in the Z-axis direction.

[0075] In this way, the inner housing upper wall 310 is fixed to the two counterweights 400 on both sides of the X-axis direction at both ends of the inner housing 300 in the positive direction of the Z-axis. In other words, the inner housing upper wall 310 is fixed to the counterweights 400 at a position in the inner housing 300 close to the opening 110a of the outer housing main body 110. Thus, when the inner housing upper wall 310 is fixed to the counterweights 400, the fixing operation becomes easy, thereby improving the workability.

[0076] When the inner housing upper wall 310 is fixed to the counterweight 400, a gap is formed between the inner housing 300 and the counterweight 400. That is, a gap is formed between the inner housing side wall 330 and the counterweight 400 in the positive direction of the X-axis, and a gap is formed between the inner housing side wall 340 and the counterweight 400 in the negative direction of the X-axis. A gap is also formed between the inner housing side walls 350 and 360 and the outer housing body 110. That is, a gap is formed between the inner housing side wall 350 and the outer housing side wall 113 in the negative direction of the Y-axis, and a gap is formed between the inner housing side wall 360 and the outer housing side wall 113 in the positive direction of the Y-axis (not shown). As a result, when the storage cell 20 is inserted into the outer housing body 110, the insertion operation becomes easy, thereby improving the workability. By forming this gap, when an impact from the X-axis direction is applied to the storage device 10, the gap can absorb the force of the impact.

[0077] The storage element unit 210 is configured in a manner that it is sandwiched by the inner shell upper wall 310 (first component) and the outer shell bottom wall 111 in the Z-axis direction (first direction). The so-called being sandwiched by two components refers to a state of directly contacting the two components without being sandwiched by other components, or a state of indirectly contacting the two components with other components sandwiched therebetween. In other words, the storage element unit 210 is in direct or indirect contact with the inner shell upper wall 310 and the outer shell bottom wall 111 in the Z-axis direction. In the present embodiment, the storage element unit 210 is in indirect contact with the inner shell upper wall 310 and the outer shell bottom wall 111 with other storage element units 210 and the inner shell bottom wall 320, and is thereby sandwiched (clamped) by the inner shell upper wall 310 and the outer shell bottom wall 111. It can also be said that the plurality of electricity storage element cells 210 (electricity storage element cell group 200 ) are in indirect contact with the inner case upper wall 310 and the outer case bottom wall 111 via the inner case bottom wall 320 , and are sandwiched (held) by the inner case upper wall 310 and the outer case bottom wall 111 .

[0078] A plate-shaped member such as a rubber plate or resin member or other member such as a weight for tolerance absorption, vibration suppression or anti-slip may also be arranged between the inner housing bottom wall 320 and the outer housing bottom wall 111. In this case, it can be defined that the inner housing bottom wall 320 or the outer housing bottom wall 111 has the plate-shaped member or other member such as a weight. In this case, it can also be said that the storage element unit 210 is arranged in a manner sandwiched by the inner housing upper wall 310 and the outer housing bottom wall 111.

[0079] [4. Description of the Effect]

[0080] As described above, according to the power storage device 10 involved in the embodiment of the present invention, the power storage element unit 210 (power storage element unit group 200) is sandwiched by the first member and the outer shell bottom wall 111, and the first member is fixed to the second member fixed to the outer shell side wall 112. As a result, the power storage element unit 210 (power storage element unit group 200) can be easily fixed to the outer shell 100, so the movement of the power storage element unit 210 (power storage element unit group 200) relative to the outer shell 100 can be restricted by a simple structure. Therefore, the vibration resistance or impact resistance of the power storage device 10 can be easily improved. In the case where the first member is fixed to the second member fixed to the outer shell side wall 112 by welding or the like, it is necessary to provide a screw hole or the like for connection with the first member in the outer shell side wall 112, so it is effective from the viewpoint of waterproofing.

[0081] By fixing the first member to the weight 400 fixed to the outer case side wall 112, the first member can be fixed to the outer case side wall 112 via the weight 400. As a result, the storage element unit 210 (storage element unit group 200) can be easily fixed to the outer case 100, so that the movement of the storage element unit 210 (storage element unit group 200) relative to the outer case 100 can be restricted by a simple structure. Since the weight is a heavy object, the vibration resistance or impact resistance can be improved.

[0082] By providing the first member as the inner case upper wall 310 serving as the upper wall of the inner case 300 that accommodates the electric storage element cell 210 (electric storage element cell group 200), the electric storage element cell 210 (electric storage element cell group 200) can be easily fixed to the outer case 100 using the inner case upper wall 310. Thus, the movement of the electric storage element cell 210 (electric storage element cell group 200) relative to the outer case 100 can be restricted by a simple structure.

[0083] The inner case 300 is assembled from three or more walls that are separate from each other (six walls, namely, the inner case upper wall 310, the inner case bottom wall 320, and the inner case side walls 330 to 360 in this embodiment). As a result, each wall can be easily arranged on the outer surface of the storage element unit 210 (storage element unit group 200). Since each wall can be arranged on the outer surface of the storage element unit 210 (storage element unit group 200), it is easy to restrict the movement of the storage element unit 210 (storage element unit group 200).

[0084] By providing the extension portion 311 on the inner case upper wall 310 (first member) and fixing the extension portion 311 to the counterweight 400 (second member), the electric storage element unit 210 (electric storage element unit group 200) can be easily fixed to the outer case 100. Thus, the movement of the electric storage element unit 210 (electric storage element unit group 200) relative to the outer case 100 can be restricted by a simple structure.

[0085] By bringing the end plate 212 (side member) of the electric storage element unit 210 into contact with the inner surface of the inner case 300 (inner case side walls 330, 340), the movement of the electric storage element unit 210 (electric storage element unit group 200) in the inner case 300 can be restricted. Since the end plate 212 (side member) can be firmly restrained by the inner case 300 after making surface contact with the inner surface of the inner case 300, the vibration resistance or impact resistance of the electric storage device 10 can be improved.

[0086] [5. Description of Modifications]

[0087] Although the power storage device 10 according to the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment. The embodiment disclosed herein is illustrative in all respects, and all modifications within the meaning and scope equivalent to the claims are included within the scope of the present invention.

[0088] In the above embodiment, the inner case upper wall 310 (first member) is fixed to the weight 400 (second member) fixed to the outer case side wall 112 , but the inner case upper wall 310 (first member) may be fixed to the outer case side wall 112 . Figure 7 It is a front view showing a structure in which an inner casing upper wall 310A according to a modification of the present embodiment is fixed to an outer casing side wall 112 . Figure 7 is with Figure 6 The corresponding figure.

[0089] like Figure 7 As shown, in this modification, the inner housing 300 has an inner housing upper wall 310A instead of the inner housing upper wall 310 in the above-mentioned embodiment. The inner housing upper wall 310A has extensions 311A ​​at both ends in the X-axis direction. The extension 311A ​​has an L-shaped fixing portion 312 that extends from the extension 311 in the above-mentioned embodiment in the X-axis direction and is bent in the positive direction of the Z-axis. The portion of the fixing portion 312 that extends in the positive direction of the Z-axis contacts the outer housing side wall 112 in the X-axis direction and is fixed to the outer housing side wall 112 in the X-axis direction.

[0090] In this modification, the fixing member 312a is inserted into the through hole formed in the fixing portion 312 and the outer shell side wall 112 to fix the fixing portion 312 and the outer shell side wall 112. Specifically, the fixing member 312a is a bolt, which is inserted into the through hole of the outer shell side wall 112 and then combined with the internal thread portion in the through hole of the fixing portion 312, so that the fixing portion 312 and the outer shell side wall 112 are fixed. In this modification, the fixing member 311a in the above embodiment is not configured in the extension portion 311A, and the fixed portion 400a in the above embodiment is not formed in the counterweight 400. The other structures of this modification are the same as those in the above embodiment, so detailed description is omitted.

[0091] As described above, according to the power storage device involved in this modification, the same effects as those of the above-mentioned embodiment are achieved. In particular, in this modification, the power storage element unit 210 (power storage element unit group 200) is sandwiched by the inner case upper wall 310A (first member) and the outer case bottom wall 111, and the inner case upper wall 310A (first member) is fixed to the outer case side wall 112. As a result, the power storage element unit 210 (power storage element unit group 200) can be easily fixed relative to the outer case 100, so that the movement of the power storage element unit 210 (power storage element unit group 200) relative to the outer case 100 can be restricted by a simple structure. Therefore, the vibration resistance or impact resistance of the power storage device 10 can be easily improved. By providing the extension portion 311A ​​on the inner case upper wall 310A (first member) and fixing the extension portion 311A ​​to the outer case side wall 112, the storage element unit 210 (storage element unit group 200) can be easily fixed to the outer case 100. Thus, the movement of the storage element unit 210 (storage element unit group 200) relative to the outer case 100 can be restricted by a simple structure.

[0092] In the above-mentioned modification, the inner housing upper wall 310A (extension 311A) is formed to be thinner than the inner housing upper wall 310 (extension 311) in the above-mentioned embodiment and the end portion in the X-axis direction is bent, so that the fixing portion 312 can be formed. The inner housing upper wall 310A (extension 311A) can also be formed by joining an L-shaped independent member as the fixing portion 312 to a flat plate-shaped member. It is also possible not to form an internal thread portion in the through hole of the fixing portion 312, and to arrange a nut on the fixing portion 312 by welding, etc., so as to combine the fixing member 312a with the nut. It is also possible to form a recess (countersink) in the outer housing side wall 112, and arrange the head of the bolt as the fixing member 312a in the recess (countersink). The fixing portion 312 may not be L-shaped but may be flat plate-shaped. The inner housing upper wall 310A may also be fixed to the outer housing side wall 113. In the above-described modification, if the weight of the power storage device does not need to be adjusted by the counterweight 400 because the outer case 100 itself is heavy or a counterweight other than the counterweight 400 is provided, the power storage device may not include the counterweight 400 (second member).

[0093] (Other variations)

[0094] In the above embodiment, the power storage device 10 may include a counterweight arranged along the outer case side wall 113 of the outer case body 110 and fixed to the outer case side wall 113, instead of the counterweight 400 or in addition to the counterweight 400. In this case, the inner case upper wall 310 may also be fixed to the counterweight fixed to the outer case side wall 113, instead of the counterweight 400 or in addition to the counterweight 400. The power storage device 10 may include other counterweights such as the counterweight arranged along the outer case bottom wall 111 in addition to the above counterweight.

[0095] In the above embodiment, the inner case upper wall 310 is fixed to the counterweight 400 by means of the extension portion 311 extending in the X-axis direction, but another member fixed to the inner case upper wall 310 may be fixed to the counterweight 400. Alternatively, a portion extending in the X-axis direction from the end of the storage element unit group 200 in the X-axis direction may be fixed to the counterweight 400.

[0096] In the above embodiment, a gap is formed between the inner housing 300 and the counterweight 400, but the inner housing 300 and the counterweight 400 may be in contact. In this case, as long as the counterweight 400 is clamped by the inner housing side wall 330 or 340 and the outer housing side wall 112 and fixed relative to the outer housing side wall 112, it may be directly joined to the outer housing side wall 112 by welding or the like. In other words, the counterweight 400 (second member) may be fixed to the outer housing side wall 112 by inserting or pressing it between the storage element unit 210 or the storage unit 20 and the outer housing side wall 112 without a gap, and may be fixed to the outer housing side wall 112. The inner housing side wall 350 or 360 and the outer housing side wall 113 may be in contact.

[0097] In the above embodiment, the inner shell 300 has six walls that are separated from each other, but it only needs to have three or more walls that are separated from each other. That is, for the inner shell 300, any number of the six walls may be integrated, or no wall may be configured. The inner shell bottom wall 320 and at least one of the inner shell side walls 330~360 may be integrated (integrally formed), or the inner shell upper wall 310 and at least one of the inner shell side walls 330~360 may be integrated (integrally formed). The inner shell bottom wall 320 and at least one of the inner shell side walls 330~360 may not be configured. The inner shell 300 may also have a rod-shaped beam or the like instead of a plate-shaped wall. The inner shell 300 may also have two components that are separated from each other or only one component.

[0098] In the above embodiment, the second member to which the inner housing upper wall 310 (first member) is fixed is the counterweight 400 for adjusting the weight of the power storage device 10, but it may also be a member such as a spacer that does not have the function of adjusting the weight of the power storage device 10. In the above embodiment, the first member fixed to the second member is the inner housing upper wall 310, but it is not limited to this. The first member may be any member as long as it is arranged on one side of the power storage element unit 210 in the first direction and sandwiches the power storage element unit 210 with the outer housing bottom wall 111 in the first direction, and may be a simple plate-shaped member or a rod-shaped member. In this case, the power storage device 10 may not have the inner housing 300.

[0099] Specifically, it can also be Figure 8 The structure shown. Figure 8 This is a front view showing a structure in which a first member 310B according to another modification of the present embodiment is fixed to the outer casing side wall 112 . Figure 8 is with Figure 6 as well as Figure 7 The corresponding figure. Figure 8 As shown, in this modification, from Figure 7In the structure shown, components other than the inner shell upper wall 310A of the inner shell 300 and the counterweight 400 are removed, and the portion extending from the inner shell upper wall 310A in the X-axis direction is removed to form the first component 310B. That is, the first component 310B is a component that is arranged on one side of the first direction (positive direction of the Z-axis) of the storage element unit 210 and clamps the storage element unit 210 with the outer shell bottom wall 111 in the first direction (Z-axis direction) and is fixed to the outer shell side wall 112. Other structures of this variant are similar to Figure 7 The structures shown are the same, so detailed description is omitted.

[0100] In the above embodiment, in the storage element unit 210, the end plate 212 is used as an example of a side member, but the side plate may be used as an example of a side member, or other members may be used as an example of a side member. For the storage element unit 210, when a plurality of storage elements 211 flat in the Y-axis direction are arranged in the Y-axis direction, end plates are arranged at both ends of the storage element unit 210 in the Y-axis direction, and side plates are arranged at both ends of the storage element unit 210 in the X-axis direction. In this case, the side plate as an example of a side member may be in contact with the inner surface of the inner case 300 (inner case side walls 330, 340). The external terminal 215 is arranged at the end of the storage element unit 210 in the Y-axis direction.

[0101] In the above embodiment, both ends of the power storage device 10 in the X-axis direction (both ends of the inner case upper wall 310 in the X-axis direction and the surrounding structure) have the above structure, but either end of the power storage device 10 in the X-axis direction may not have the above structure.

[0102] In the above embodiment, the power storage device includes an outer case that accommodates an inner case and an inner case that accommodates the power storage element unit, but the power storage device may not include an inner case and may include a first member disposed on the positive side of the power storage element unit in the Z-axis direction.

[0103] In the above embodiment, the outer shell 100 may not have the outer shell cover 120, etc., and the power storage device 10 is not limited to having all the above structures. The power storage element unit 210 may not have the end plate 212 and the side plate 213. In other words, the power storage element unit 210 may not be a structure constrained by the end plate 212 and the side plate 213, but may be a structure in which the power storage element 211 and the like are accommodated in an integral box (container) molded of resin.

[0104] Any combination of the above-described embodiments and modifications is also included in the scope of the present invention.

[0105] Industrial Applicability

[0106] The present invention can be applied to a power storage device or the like including a power storage element unit having a power storage element such as a secondary battery.

[0107] Description of Reference Numerals

[0108] 10: power storage device, 20: power storage unit, 100: outer shell, 110: outer shell body, 110a: opening, 111: outer shell bottom wall, 112, 113: outer shell side wall, 120: outer shell cover, 200: power storage element unit group, 210: power storage element unit, 211: power storage element, 212: end plate, 213: side plate, 215: external terminal, 300: inner shell, 310, 310A: inner shell upper wall, 310B: first member, 311, 311A: extension part, 311a, 312a: fixing member, 312: fixing part, 320: inner shell bottom wall, 330, 340, 350, 360: inner shell side wall, 400: counterweight, 400a: fixed part.

Claims

1. A power storage device, wherein: The power storage device comprises: A power storage element unit having a power storage element; An outer shell having an outer shell body with one side opened in a first direction and accommodating the electric storage element unit; as well as a first member disposed on one side of the power storage element unit in the first direction; The outer shell has: an outer shell bottom wall arranged on the other side of the first direction; and an outer shell side wall opposite to the second direction intersecting the first direction, The first member is fixed to the second member fixed to the side wall of the outer shell, or the first member is fixed to the side wall of the outer shell.

2. The power storage device according to claim 1, wherein The second member is a counterweight.

3. The power storage device according to claim 1 or 2, wherein: The first member has an extension portion extending toward the side wall of the outer shell, The extension portion is fixed to the second component or the side wall of the outer shell.

4. The power storage device according to claim 1 or 2, wherein: The power storage device further includes an inner case that is accommodated in the outer case and accommodates and holds the power storage element unit. The first member is an upper wall of the inner housing.

5. The power storage device according to claim 4, wherein: The inner housing has three or more walls which are separated from each other.

6. The power storage device according to claim 4, wherein: The electric storage element unit includes a side member disposed on a side of the electric storage element. The side members are in contact with an inner surface of the inner case.

Images