Power storage apparatus

Abstract

To provide a power storage apparatus with a simple configuration that can be connected to a plurality of power storage device units each including a plurality of power storage devices.SOLUTION: A power storage apparatus includes a plurality of power storage device unit groups 31. Each of the plurality of power storage device unit groups includes a plurality of power storage device units 200 arranged in a first direction. Each of the power storage units includes a plurality of power storage devices and a pair of outer terminals 251 arranged in the first direction. The plurality of power storage unit groups are arranged in a second direction crossing the first direction. The plurality of power storage device units included in each of the plurality of power storage unit groups are connected in series. The plurality of power storage device units are connected in parallel.SELECTED DRAWING: Figure 9

Description

Technical Field

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

Background Art

[0002] Patent Document 1 discloses a battery pack in which a plurality of battery modules each including a plurality of battery cells are housed in a housing, a first harness connected to each battery module is connected to a first gathering portion, and a second harness connected to each battery module is connected to a second gathering portion.

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the battery pack disclosed in Patent Document 1, a plurality of battery modules each including a plurality of battery cells are connected in a complicated configuration. That is, a first harness and a second harness are connected to each of the plurality of battery modules, the first harness is connected to a first gathering portion, and the second harness is connected to a second gathering portion, and the connection configuration of the plurality of battery modules is complicated.

[0005] The present invention has been made by the inventors of the present application newly paying attention to the above problems, and an object thereof is to provide a power storage device capable of connecting a plurality of power storage element units each including a plurality of power storage elements in a simple configuration.

Means for Solving the Problems

[0006] The power storage device according to one aspect of the present invention includes a plurality of power storage element unit groups. Each of the plurality of power storage element unit groups includes a plurality of power storage element units arranged in a first direction. Each of the plurality of power storage element units includes a plurality of power storage elements and a pair of external terminals arranged in the first direction. The plurality of power storage element unit groups are arranged in a second direction intersecting the first direction. The plurality of power storage element units included in each of the plurality of power storage element unit groups are connected in series, and the plurality of power storage element unit groups are connected in parallel.

Effects of the Invention

[0007] According to the power storage device of the present invention, a plurality of power storage element units each including a plurality of power storage elements can be connected with a simple configuration.

Brief Description of the Drawings

[0008]

Figure 1

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Figure 9

Figure 10

Figure 11

[0009] (1) A power storage device according to one aspect of the present invention includes a plurality of power storage element unit groups. Each of the plurality of power storage element unit groups includes a plurality of power storage element units arranged in a first direction. Each of the plurality of power storage element units includes a plurality of power storage elements and a pair of external terminals arranged in the first direction. The plurality of power storage element unit groups are arranged in a second direction intersecting the first direction. The plurality of power storage element units included in each of the plurality of power storage element unit groups are connected in series, and the plurality of power storage element unit groups are connected in parallel.

[0010] According to this, in the power storage device, a plurality of power storage element units each including a plurality of power storage elements and a pair of external terminals arranged in the first direction are arranged in the first direction and connected in series to form a power storage element unit group, and the plurality of power storage element unit groups are arranged in the second direction and connected in parallel. Thereby, a plurality of power storage element units each including a plurality of power storage elements can be arranged so as to be easily connected in series and in parallel, and the connection form can be made into a simple configuration.

[0011] (2) The power storage device according to (1) above may include at least one bus bar that extends in the second direction and connects the plurality of power storage element unit groups in parallel.

[0012] According to this, on one of the positive and negative electrode sides, simple parallel connection is performed by the bus bar, while on the other electrode side, various connection forms can be supported.

[0013] (3) The power storage device according to (2) above may include a first bus bar and a second bus bar that extend in the second direction and connect the plurality of power storage element unit groups in parallel.

[0014] According to this, a plurality of power storage element unit groups can be easily connected in parallel by a pair of bus bars (the first bus bar and the second bus bar).

[0015] (4) In the power storage device according to (3) above, each of the plurality of power storage element unit groups includes a first terminal that is one series end and a second terminal that is the other series end, the first bus bar is connected to the first terminal of each power storage element unit group, and the second bus bar may be connected to the second terminal of each power storage element unit group.

[0016] According to this, by connecting the first bus bar to the first terminal that is one series end of each power storage element unit group and connecting the second bus bar to the second terminal that is the other series end of each power storage element unit group, a plurality of power storage element unit groups can be easily connected in parallel.

[0017] (5) In the power storage device according to (3) above, each of the plurality of power storage element unit groups includes a first terminal that is one series end and a second terminal that is the other series end, the power storage device includes a first conductive member connected to the first terminal for each of the plurality of power storage element unit groups, each first conductive member is electrically connected to the first bus bar, and the second bus bar may be connected to the second terminal of each power storage element unit group.

[0018] According to this, a first conductive member is connected to a first terminal which is one of the series ends of each power storage element unit group, each first conductive member is electrically connected to a first bus bar, and a second bus bar is connected to a second terminal which is the other series end of each power storage element unit group. That is, the first bus bar is connected to the first terminal of each power storage element unit group via the first conductive member. Thereby, the degree of freedom in the arrangement position of the first bus bar can be improved, such as the first bus bar can be arranged on a side different from the second bus bar with respect to a plurality of power storage element unit groups.

[0019] (6) The power storage device according to any one of (3) to (5) above may include a first wiring member and a second wiring member which are one and the other of a positive electrode wiring member and a negative electrode wiring member in which currents flowing through each of the power storage element unit groups are integrated, the first wiring member is connected to a first end portion of the first bus bar, and the second wiring member is connected to a second end portion of the second bus bar.

[0020] According to this, by connecting a first wiring member and a second wiring member (main circuit wiring members) which are one and the other of a positive electrode wiring member and a negative electrode wiring member to the end portions of the bus bar, it is possible to suppress the main circuit wiring members from interfering with the power storage element unit groups, and it becomes easier to arrange the main circuit wiring members.

[0021] (7) In the power storage device according to (6) above, the first end portion is located in a range from the parallel connection location on the one side in the second direction among the parallel connection locations of the first bus bar with the plurality of power storage element unit groups to the edge on the one side in the second direction of the first bus bar, and the second end portion is located in a range from the parallel connection location on the other side in the second direction among the parallel connection locations of the second bus bar with the plurality of power storage element unit groups to the edge on the other side in the second direction of the second bus bar on the side opposite to the other parallel connection locations.

[0022] According to this, since the first end portion is located at one end portion of the first bus bar in the second direction and the second end portion is located at the other end portion of the second bus bar in the second direction, the first wiring member is connected to one end portion of the first bus bar in the second direction, and the second wiring member is connected to the other end portion of the second bus bar in the second direction. Thereby, in each power storage element unit group, the total value of the wiring distance (length of current path) to the first wiring member and the wiring distance (length of current path) to the second wiring member can be made equal (can be made equal-length wiring).

[0023] (8) The power storage device according to any one of (1) to (7) above may further include a control wiring member for controlling at least one power storage element unit among the plurality of power storage element units, and the control wiring member may be led out from the side opposite to the pair of external terminals of the plurality of power storage element units in a third direction intersecting the first direction and the second direction.

[0024] According to this, since the control wiring member is led out from the side opposite to the external terminal of the power storage element unit in the third direction, it is possible to suppress the control wiring member from interfering with the wiring member (main circuit wiring member) connected to the external terminal. By separately arranging the control wiring member and the main circuit wiring member, the influence of noise from the main circuit wiring member on the control wiring member can be reduced.

[0025] (9) In the power storage device according to any one of (1) to (8) above, the plurality of power storage element unit groups may be connected in parallel by a bus bar arranged at a position in the first direction of the plurality of power storage element unit groups and overlapping the plurality of power storage element unit groups when viewed from the first direction.

[0026] According to this, by arranging the bus bar for connecting the plurality of power storage element unit groups in a position overlapping the plurality of power storage element unit groups when viewed from the first direction, the degree of freedom in the arrangement position of the bus bar can be improved, such as being able to arrange the bus bar on a side different from other bus bars with respect to the plurality of power storage element unit groups.

[0027] Hereinafter, with reference to the drawings, a power storage device according to an embodiment (including its modifications) of the present invention will be described. Each of the embodiments described below shows comprehensive or specific examples. The numerical values, shapes, materials, components, arrangement positions and connection forms of the components, manufacturing processes, order of manufacturing processes, etc. shown in the following embodiments are merely examples and are not intended to limit the present invention. In each figure, dimensions and the like are not strictly illustrated. In each figure, the same or similar components are denoted by the same reference numerals.

[0028] In the following description and drawings, the arrangement direction of the power storage element unit group, the arrangement direction of the main body and the lid of the container of the power storage element, or the protruding direction of the terminal of the power storage element is defined as the X-axis direction. The facing direction between the front surface (the surface on which the external terminal is arranged) and the rear surface of the power storage element unit, or the protruding direction of the external terminal of the power storage element unit is defined as the Y-axis direction. The arrangement direction of the power storage element units included in the power storage element unit group, the arrangement direction of the power storage element unit (power storage unit) and the electrical component, the arrangement direction of a pair of external terminals included in the power storage element unit, or the vertical direction is defined as the Z-axis direction. These X-axis direction, Y-axis direction and Z-axis direction are directions that intersect (orthogonal in this embodiment) with each other.

[0029] In the following description, the X-axis plus direction indicates the arrow direction of the X-axis, and the X-axis minus direction indicates the direction opposite to the X-axis plus direction. When simply referring to the X-axis direction, it indicates both the X-axis plus direction and the X-axis minus direction or either one of the directions. The same applies to the Y-axis direction and the Z-axis direction. Hereinafter, the Z-axis direction may also be referred to as the first direction, the X-axis direction may also be referred to as the second direction, and the Y-axis direction may also be referred to as the third direction. Expressions indicating relative directions or postures such as parallel and orthogonal include cases where they are not strictly in that direction or posture. For example, when two directions are parallel, it means not only that the two directions are completely parallel, but also that they are substantially parallel, that is, including a difference of, for example, about several percent. In the following description, when expressing "insulation", it means "electrical insulation". The material having insulating properties has a volume resistivity of 1×10 10It is preferably formed of a material of Ωm or more.

[0030] (Embodiment) [1 General description of the power storage device 10] First, a general description of the power storage device 10 in the present embodiment will be given. FIG. 1 is a perspective view showing the appearance of the power storage device 10 according to the present embodiment. FIG. 2 is a perspective view showing a state in which the lid member 140 and the first fixing member 700 are removed from the power storage device 10 according to the present embodiment. FIG. 3 is a perspective view showing the internal configuration of the outer case 100 of the power storage device 10 according to the present embodiment. In FIG. 3, a state in which the power storage unit 20, the elastic member 800, and the gasket 900 are taken out from the inside of the outer case 100 is shown. In FIG. 3, the illustration of the lid member 140 and the first fixing member 700 shown in FIG. 2 is omitted. FIG. 4 is an exploded perspective view and a cross-sectional view showing the configuration of the outer case 100 included in the power storage device 10 according to the present embodiment. FIG. 4(a) is an exploded perspective view showing each component when the outer case 100 is disassembled. FIG. 4(b) is a cross-sectional view showing the configuration when the end portion in the negative Z-axis direction (the portion including the intermediate member 130) of the outer case 100 is cut by a plane parallel to the YZ plane. In FIG. 4, the illustration of the lid member 140 included in the outer case 100 shown in FIG. 2 is omitted. FIG. 5 is an exploded perspective view showing the configuration of the power storage unit 20 included in the power storage device 10 according to the present embodiment. For convenience of explanation, FIG. 1 shows a state in which the case lid 150 is removed from the case main body 110 of the outer case 100, and the illustration of the case lid 150 is omitted from FIG. 2 onwards.

[0031] The power storage device 10 is a device that can charge electricity from the outside and discharge electricity to the outside. In this embodiment, it has a substantially rectangular parallelepiped shape. A rectangular parallelepiped is a hexahedron in which all faces are composed of rectangles or squares. The power storage device 10 is used for power storage applications or power supply applications, etc. The power storage device 10 is used as a battery for driving a moving body such as a forklift, construction machinery, agricultural machinery, an automatic guided vehicle (AGV), an automobile, a motorcycle, a watercraft, a ship, a snowmobile, or a railway vehicle for electric railways, or for engine starting, etc. Examples of the above-mentioned automobiles include electric vehicles (EV), hybrid electric vehicles (HEV), plug-in hybrid electric vehicles (PHEV), and fossil fuel (gasoline, light oil, liquefied natural gas, etc.) automobiles. Examples of the above-mentioned railway vehicles for electric railways include trains, monorails, linear motor cars, and hybrid trains equipped with both a diesel engine and an electric motor. The power storage device 10 can also be used as a stationary battery for household or business use, etc.

[0032] As shown in FIGS. 1 to 3 and the like, the power storage device 10 includes an outer case 100, a power storage unit 20, a first fixing member 700, an elastic member 800, and a gasket 900. As shown in FIGS. 1 to 4, the outer case 100 includes a case body 110, a weight 120, an intermediate member 130, a lid member 140, and a case lid 150. As shown in FIGS. 3 and 5 and the like, the power storage unit 20 includes a power storage unit main body 30 composed of a plurality of power storage element units 200 and the like, an inner case 300, an elastic member 400, a connector 500, an electrical component 510, a cover 600, a control wiring member 514, and main circuit wiring members such as a first wiring member 515 and a second wiring member 516 (see FIGS. 7 and 8).

[0033] [1.1 Explanation of the outer case 100] The outer case 100 is a rectangular parallelepiped-shaped (box-shaped) container (outer box) that constitutes the outer case (outer packaging body, housing, outer shell) of the power storage device 10. The outer case 100 is disposed outside the power storage unit 20, the first fixing member 700, the elastic member 800, the gasket 900, etc., houses the power storage unit 20, etc., fixes the power storage unit 20, etc. at a predetermined position, and protects them from impacts, etc. Hereinafter, the case body 110, the weight 120, the intermediate member 130, the lid member 140, and the case lid 150 included in the outer case 100 will be described in detail.

[0034] The case body 110 is a box-shaped member that constitutes the main body of the outer case 100. The case body 110 is a bottomed rectangular cylindrical container in which a rectangular opening 100a is formed in the positive Z-axis direction. The case lid 150 is a flat plate-shaped member that constitutes the lid of the outer case 100. The case lid 150 is connected (joined) to the case body 110 and closes the opening 100a of the case body 110. The case lid 150 is not limited to a flat plate shape as long as it can close the opening 100a, and may be a bottomed rectangular cylindrical shape or any other shape. The case body 110 and the case lid 150 are metal cases formed of metal members such as steel plates, plated steel plates, iron, aluminum, aluminum alloys, and stainless steel. The case body 110 or the case lid 150 may be formed of an insulating member such as any resin material that can be used for the terminal cover 260 of the power storage element unit 200 described later.

[0035] The case body 110 includes outer case side walls 111, which are a pair of flat plate-shaped and rectangular long side walls, on both sides in the Y-axis direction, and outer case side walls 112, which are a pair of flat plate-shaped and rectangular short side walls, on both sides in the X-axis direction. The case body 110 includes an outer case bottom wall 113, which is a flat plate-shaped and rectangular bottom wall, in the negative Z-axis direction. As a result, an opening 100a is formed on the side of the case body 110 opposite to the outer case bottom wall 113. That is, the outer case 100 has an opening 100a on the side opposite to the outer case bottom wall 113.

[0036] The outer case side wall 111 is a wall that faces (is orthogonal to) in the Y-axis direction and is disposed at the end of the case body 110 in the Y-axis direction. The outer case side wall 112 is a wall that faces (is orthogonal to) in the X-axis direction and is disposed at the end of the case body 110 in the X-axis direction. The outer case bottom wall 113 is a wall that faces (is orthogonal to) in the Z-axis direction and is disposed at the end of the case body 110 in the minus Z-axis direction. Depending on the configuration (number, size, shape, etc.) of the contents of the outer case 100, etc., the case body 110 (the outer case side walls 111, 112, and the outer case bottom wall 113) may have any shape. In this case, the outer case side wall 111 may be a short side wall and the outer case side wall 112 may be a long side wall.

[0037] At least one of the outer case side walls 111, 112, and the outer case bottom wall 113 is formed with a through portion, which is an opening (through hole, through aperture) that penetrates the wall. In the present embodiment, a through portion 111a that penetrates the outer case side wall 111 in the Y-axis direction is formed in the outer case side wall 111. Further, at least one of the outer case side walls 111, 112, and the outer case bottom wall 113 is formed with a plurality of through portions 111a. In the present embodiment, through portions 111a are formed in each of the pair of outer case side walls 111. That is, two through portions 111a are formed in the two opposing outer case side walls 111 provided in the outer case 100. The through portion 111a is a rectangular opening formed at the end of the outer case side wall 111 in the minus Z-axis direction and extending in the X-axis direction when viewed from the Y-axis direction.

[0038] A connector opening 112a is formed in the outer case side wall 112 in the plus X-axis direction. The connector opening 112a is a rectangular through hole disposed at the end of the outer case side wall 112 in the plus Z-axis direction in the plus X-axis direction, and the connector 500 penetrates through it.

[0039] The outer case 100 is further formed with openings 111b and 112b. That is, the openings 111b are formed in each of the pair of outer case side walls 111, and the openings 112b are formed in each of the pair of outer case side walls 112. The openings 111b and 112b are circular through holes provided at the Z-axis plus direction ends of the outer case side walls 111 and 112. The liquids such as water or condensed water that enter the outer case 100 are discharged to the outside of the outer case 100 through the openings 111b and 112b.

[0040] The weight 120 is a weight disposed inside the case body 110. The weight 120 is a weight (counterweight) for adjusting the weight of the power storage device 10. The weight of the weight 120 is appropriately determined as the weight required for adjusting the weight of the power storage device 10. The total weight of all the weights 120 provided in the power storage device 10 is preferably 1 / 5 or more, more preferably 1 / 4 or more, and even more preferably 1 / 3 or more of the total weight of the power storage device 10. The material of the weight 120 is not particularly limited, but it can be formed of any metal member such as a steel plate, a plated steel plate, iron, aluminum, an aluminum alloy, or stainless steel that can be used for the case body 110.

[0041] As shown in FIG. 4, the weight 120 includes a pair of plate-shaped and rectangular weights 121 parallel to the XZ plane on both sides in the Y-axis direction, and a pair of plate-shaped and rectangular weights 122 parallel to the YZ plane on both sides in the X-axis direction. The weight 120 further includes a rectangular ring-shaped connecting member 123 and an auxiliary member 124 in the Z-axis plus direction of the pair of weights 121 and the pair of weights 122, as viewed from the Z-axis direction.

[0042] The weight 121 faces the outer case side wall 111 of the case body 110 and is arranged in a state of being in contact with the outer case side wall 111. The weight 121 is joined (fixed) to the outer case side wall 111 by welding (such as spot welding) or the like. In the present embodiment, a pair of weights 121 are joined (fixed) to the inner surfaces of the pair of outer case side walls 111. The weight 122 faces the outer case side wall 112 of the case body 110 and is arranged in a state of being in contact with the outer case side wall 112. The weight 122 is joined (fixed) to the outer case side wall 112 by welding (such as spot welding) or the like. In the present embodiment, a pair of weights 122 are joined (fixed) to the inner surfaces of the pair of outer case side walls 112. The weights 121 and 122 may be joined (fixed) to the outer case side walls 111 and 112 by adhesion with an adhesive or double-sided tape, welding, bolt connection, caulking joint, or the like. The weight 121 is shorter than the weight 122 in the Z-axis direction. The Z-axis plus direction ends of the weight 121 and the weight 122 are arranged at the same position in the Z-axis direction. Thereby, a space is formed between the Z-axis minus direction of the weight 121 and the pair of weights 122, and the intermediate member 130 is arranged in this space.

[0043] The connecting member 123 and the auxiliary member 124 are members to which the partition wall 340 of the inner case 300 described later is fixed (see FIG. 7 etc.). That is, the connecting member 123 is a member that connects the outer case 100 and the upper wall (partition wall 340) of the inner case 300. A plurality of fixing portions 123a and 124a for fixing the power storage unit 20 (partition wall 340) are provided on the connecting member 123 and the auxiliary member 124. The connecting member 123 is joined (fixed) to the pair of weights 121 and the pair of weights 122 by welding or the like, and the auxiliary member 124 is joined (fixed) to the connecting member 123 by welding or the like. In the present embodiment, the connecting member 123 is divided into four members corresponding to each of the pair of weights 121 and the pair of weights 122, but it may be divided into any number of members or may be formed of one member. The same applies to the auxiliary member 124. The auxiliary member 124 is formed to be thinner in the Z-axis direction than the connecting member 123. The auxiliary member 124 is arranged along the gasket 900 and has a function of restricting the thickness of the gasket 900 in the Z-axis direction so as not to excessively crush the gasket 900. The auxiliary member 124 has a thickness similar to that of the gasket 900 and is thinner than the thickness of the gasket 900 before being crushed.

[0044] The intermediate member 130 is a member to which the first fixing member 700 is fixed. By fixing the intermediate member 130 to the case body 110, the first fixing member 700 is fixed to the case body 110. Specifically, the intermediate member 130 is arranged surrounded by one weight 121, the pair of weights 122, and the outer case bottom wall 113, and is fixed to the case body 110 by being joined (fixed) to at least one of these by welding or the like. At least a part (the whole of the intermediate member 130 in the present embodiment) of the intermediate member 130 is arranged in the through-hole 111a of the outer case side wall 111 when viewed from the Y-axis direction. In the present embodiment, a pair of intermediate members 130 are arranged on both sides of the outer case 100 in the Y-axis direction.

[0045] As shown in FIG. 4, the intermediate member 130 includes an intermediate member main body 131, an auxiliary member 132, and a gasket 133. The intermediate member main body 131 includes a rectangular annular frame body 131a that is long in the X-axis direction when viewed from the Y-axis direction, and a column portion 131b that is disposed at the central portion of the frame body 131a in the X-axis direction and extends in the Z-axis direction. The column portion 131b has a function of reinforcing the central portion of the frame body 131a in the X-axis direction and suppressing deformation of the frame body 131a. A plurality of fixing portions 131c for fixing the lid member 140 are provided on the frame body 131a and the column portion 131b. A plurality of fixing portions 131d for fixing the first fixing member 700 are provided on the frame body 131a.

[0046] Similar to the intermediate member main body 131, the auxiliary member 132 includes a rectangular annular frame body 132a that is long in the X-axis direction when viewed from the Y-axis direction, and a column portion 132b that is disposed at the central portion of the frame body 132a in the X-axis direction and extends in the Z-axis direction. A plurality of fixing portions 132c for fixing the lid member 140 are provided on the frame body 132a and the column portion 132b. The auxiliary member 132 is formed to be thinner in the Y-axis direction than the intermediate member main body 131, and is joined (fixed) to the intermediate member main body 131 by welding or the like. The gasket 133 is a rectangular annular gasket that is disposed on the intermediate member main body 131 along the outer periphery of the auxiliary member 132 and is long in the X-axis direction when viewed from the Y-axis direction. That is, the auxiliary member 132 is a member for increasing the bulk of the intermediate member main body 131. The gasket 133 is disposed in a stepped portion (groove portion) formed on the intermediate member main body 131 and on the outer periphery of the auxiliary member 132. The auxiliary member 132 is disposed along the gasket 133 and has a function of restricting the thickness of the gasket 133 in the Y-axis direction so as not to excessively crush the gasket 133.

[0047] The materials of the intermediate member body 131 and the auxiliary member 132 are not particularly limited, and they can be formed of any metal member such as a steel plate, a plated steel plate, iron, aluminum, an aluminum alloy, stainless steel, etc., that can be used for the case body 110. The material of the gasket 133 is also not particularly limited, and it can be formed of rubber such as natural rubber (NR), nitrile rubber (NBR), silicone rubber (Si), styrene butadiene rubber (SBR), chloroprene rubber (CR), butyl rubber (IIR), ethylene propylene rubber (EPDM), urethane rubber (U), fluororubber, etc., or a member having elasticity such as sponge, or any resin material that can be used for the terminal cover 260 of the power storage element unit 200 described later.

[0048] The lid member 140 is a member that closes the through-hole 111a in the outer case side wall 111 of the case body 110. The lid member 140 is fixed to the outer case side wall 111 by being attached to the intermediate member 130 to close the through-hole 111a. In the present embodiment, a pair of lid members 140 are arranged on both sides in the Y-axis direction of the outer case 100, and the through-holes 111a in the pair of outer case side walls 111 are closed by the pair of lid members 140. As shown in FIG. 2 and the like, the lid member 140 is a flat plate-shaped and rectangular member that is long in the X-axis direction parallel to the XZ plane, and is provided with a plurality of fixing portions 141 on the outer peripheral portion. The fixing portion 141 is a member that attaches (fixes) the lid member 140 to the intermediate member 130 by being fixed to the intermediate member 130. In the present embodiment, the fixing portion 141 is a bolt having a male screw portion, passes through the fixing portion 132c of the auxiliary member 132, and is coupled to the female screw portion formed in the fixing portion 131c of the intermediate member body 131.

[0049] As described above, the outer case 100 is a rectangular parallelepiped, and a rectangular parallelepiped is a hexahedron. The outer case 100 is composed of six wall portions, and the wall portions constituting the outer case 100 are walls including at least one face of the hexahedron. That is, the outer case side wall 111 and the lid member 140 form the wall portions of the outer case 100. The outer case side wall 111 in which the lid member 140 is not arranged and the through-hole 111a is formed may be defined as the wall portion of the outer case 100.

[0050] [1.2 Description of the power storage unit 20] Next, the power storage unit main body 30, inner case 300, elastic member 400, connector 500, electrical component 510, and cover 600 included in the power storage unit 20 will be described in detail.

[0051] As shown in FIG. 5 and FIG. 7 described later, the power storage unit main body 30 includes a power storage element unit group 31, a first bus bar 41, a second bus bar 42, a first conductive member 513, and electrical components (such as electrical component 511) that are part of the current path of the main circuit of the power storage unit main body 30. Specifically, the power storage unit main body 30 includes a plurality of power storage element unit groups 31 arranged in the X-axis direction (the second direction intersecting the first direction). In the present embodiment, six power storage element unit groups 31 are arranged side by side in the X-axis direction. Each of the plurality of power storage element unit groups 31 includes a plurality of power storage element units 200 arranged in the Z-axis direction (the first direction) and a third bus bar 43 that electrically connects the plurality of power storage element units 200. In the present embodiment, in each power storage element unit group 31, two power storage element units 200 are arranged side by side in the Z-axis direction. The number of power storage element unit groups 31 included in the power storage unit main body 30 and the number of power storage element units 200 included in the power storage element unit group 31 are not particularly limited, and any number of power storage element unit groups 31 may be arranged in the X-axis direction, and any number of power storage element units 200 may be arranged in the Z-axis direction. A plurality of power storage element units 200 (a plurality of power storage element unit groups 31) may be arranged in the Y-axis direction. The power storage unit main body 30 may include only one power storage element unit group 31. In the present embodiment, the plurality of power storage element units 200 included in the power storage element unit group 31 are connected in series, and the plurality of power storage element unit groups 31 are connected in parallel, but any power storage element units 200 may be connected in series or in parallel. A detailed description of the configuration of the power storage element unit 200 will be described later.

[0052] In this embodiment, two adjacent power storage element units 200 are in direct or indirect surface contact with each other. That is, the power storage element units 200 arranged in the X-axis direction are in surface contact in the X-axis direction, or are in surface contact in the X-axis direction on both surfaces of the member between the power storage element units 200. Examples of the member between the power storage element units 200 include an elastic member 421 or a member similar to the elastic member 420 described later. The power storage element units 200 arranged in the Z-axis direction are in surface contact in the Z-axis direction, or are in surface contact in the Z-axis direction on both surfaces of the member between the power storage element units 200. Examples of the member between the power storage element units 200 include a member similar to the elastic member 440 described later.

[0053] The inner case 300 is a substantially rectangular parallelepiped-shaped (box-shaped) container (inner box) that constitutes the inner case (housing) of the power storage device 10. The inner case 300 is disposed inside the outer case 100 (inside the outer case 100), houses and holds a plurality of power storage element units 200 (power storage unit main bodies 30), and protects them from impacts and the like. The inner case 300 is a metal case formed of a metal member such as a steel plate, a plated steel plate, iron, aluminum, an aluminum alloy, or stainless steel. In this embodiment, the inner case 300 is formed of a member of the same material as the outer case 100, but may be formed of a member of a different material from the outer case 100. The inner case 300 may be formed of an insulating member such as any resin material that can be used for the terminal cover 260 of the power storage element unit 200 described later.

[0054] The inner case 300 includes a pair of first wall members 310 that constitute a pair of long side walls of the inner case 300, a second wall member 320 that constitutes one short side wall, a third wall member 330 that constitutes the other short side wall and the bottom wall, and a partition wall 340 that constitutes the upper wall. In the present embodiment, the pair of first wall members 310, the second wall member 320, the third wall member 330, and the partition wall 340 are all configured separately. The third wall member 330 integrally includes a side wall 331 and a bottom wall 332 that are two walls facing different directions (X-axis direction and Z-axis direction). That is, the inner case 300 includes five wall members configured separately from each other. The inner case 300 may include four or three wall members in which any one of the wall members is integrated and configured separately. That is, the inner case 300 includes three or more wall members configured separately, and at least one of the three or more wall members (the third wall member 330) integrally includes two walls facing different directions. The side wall 331 and the bottom wall 332 of the third wall member 330 may be configured separately, and the inner case 300 may include six wall members configured separately.

[0055] The pair of first wall members 310 are flat plate-shaped and rectangular walls parallel to the XZ plane, which are arranged on both sides of the power storage unit main body 30 in the Y-axis direction. The pair of first wall members 310 are joined (fixed) to the second wall member 320, the third wall member 330, and the partition wall 340 by means of bolting or the like. Each first wall member 310 is provided with a plurality of fixing portions 310b for fixing to the second wall member 320, a plurality of fixing portions 310c for fixing to the side wall 331 of the third wall member 330, and a plurality of fixing portions 310d for fixing to the bottom wall 332 of the third wall member 330. Further, the first wall member 310 is provided with a plurality of fixing portions 310a for fixing the first fixing member 700.

[0056] The second wall member 320 is a flat and rectangular wall parallel to the YZ plane, which is arranged in the positive X-axis direction of the power storage unit main body 30. The second wall member 320 is joined (fixed) to the pair of first wall members 310, the bottom wall 332 and the partition wall 340 of the third wall member 330 by means of bolting or the like. The second wall member 320 is provided with a plurality of fixing portions 320a for fixing to the pair of first wall members 310, a plurality of fixing portions 320b for fixing to the bottom wall 332, and a plurality of fixing portions 320c for fixing to the partition wall 340.

[0057] The side wall 331 of the third wall member 330 is a flat and rectangular wall parallel to the YZ plane, which is arranged in the negative X-axis direction of the power storage unit main body 30. The side wall 331 is joined (fixed) to the pair of first wall members 310 and the partition wall 340 by means of bolting or the like. The side wall 331 is provided with a plurality of fixing portions 331a for fixing to the pair of first wall members 310 and a plurality of fixing portions 331b for fixing to the partition wall 340.

[0058] The bottom wall 332 of the third wall member 330 is a flat and rectangular wall parallel to the XY plane, which is arranged in the negative Z-axis direction of the power storage unit main body 30. The bottom wall 332 is joined (fixed) to the pair of first wall members 310 and the second wall member 320 by means of bolting or the like. The bottom wall 332 is provided with a plurality of fixing portions 332a for fixing to the pair of first wall members 310 and a plurality of fixing portions 332b for fixing to the second wall member 320.

[0059] The partition wall 340 is a flat and rectangular wall parallel to the XY plane, which is arranged in the positive Z-axis direction of the power storage unit main body 30. The partition wall 340 is joined (fixed) to the pair of first wall members 310, the second wall member 320 and the side wall 331 of the third wall member 330 by means of bolting or the like. The partition wall 340 is provided with a plurality of fixing portions 342 for fixing to the pair of first wall members 310, the second wall member 320 and the side wall 331.

[0060] The partition wall 340 is further provided with a plurality of second fixing members 341 for fixing to the outer case 100, a plurality of openings 343 through which a first conductive member 513 described later penetrates, and a plurality of openings 344 through which a control wiring member 514 described later penetrates. The main circuit wiring member (second wiring member 516) penetrates the opening 343 at the end in the positive X-axis direction. The plurality of second fixing members 341 are arranged at predetermined intervals over the entire circumference of the outer peripheral portion of the partition wall 340. The plurality of openings 343 are arranged at predetermined intervals from one end to the other end in the X-axis direction at the end in the negative Y-axis direction of the partition wall 340. The plurality of openings 344 are arranged at predetermined intervals from one end to the other end in the X-axis direction at the end in the positive Y-axis direction of the partition wall 340.

[0061] The second fixing member 341 is a member that attaches (fixes) the partition wall 340 to the outer case 100 by being fixed to the weight 120 of the outer case 100. In the present embodiment, the second fixing member 341 is a bolt having a male screw portion, penetrates the fixing portion 124a of the auxiliary member 124 of the weight 120, and is coupled to the female screw portion formed in the fixing portion 123a of the connecting member 123. Thereby, when the partition wall 340 is fixed to the weight 120, the power storage unit 20 is fixed to the outer case 100. Since the partition wall 340 is disposed at a position closer to the opening 100a than the outer case bottom wall 113 of the outer case 100, the second fixing member 341 fixes the power storage unit 20 and the outer case 100 at a position closer to the opening 100a than the outer case bottom wall 113.

[0062] When the partition wall 340 is fixed to the weight 120, the space inside the outer case 100 is partitioned vertically. Thus, the partition wall 340 also serves to partition the space inside the outer case 100. That is, the space inside the outer case 100 is partitioned by the partition wall 340 which is a part of the inner case 300.

[0063] The pair of first wall members 310, second wall members 320, third wall members 330, and partition wall 340 may be joined by welding, adhesion, or the like. The pair of first wall members 310, second wall members 320, third wall members 330, and partition wall 340 may all be formed of members of the same material, or any of them may be formed of members of different materials. Depending on the size, shape, etc. of the power storage unit main body 30, the pair of first wall members 310, second wall members 320, third wall members 330, and partition wall 340 may have any shape. In this case, the pair of first wall members 310 may be short side walls, and the side walls 331 of the second wall members 320 and third wall members 330 may be long side walls.

[0064] The elastic member 400 is a member disposed between at least one of the two wall members sandwiching the plurality of power storage element units 200 provided in the inner case 300 and the plurality of power storage element units 200. The elastic member 400 is a sheet-like elastic member having functions such as tolerance absorption, vibration suppression, or anti-slip. The elastic member 400 can be formed of an elastic member or the like among those that can be used for the gasket 133 described above. In the present embodiment, the elastic member 400 is disposed between each of the two wall members sandwiching the power storage unit main body 30 and the power storage unit main body 30 in three directions of the X-axis direction, Y-axis direction, and Z-axis direction.

[0065] Specifically, an elastic member 410 is disposed between the pair of first wall members 310 and the power storage unit main body 30 (such as the protruding portion 221 of the power storage element unit 200 described later). An elastic member 420 is disposed between the second wall member 320 and the power storage unit main body 30. Further, an elastic member 421 is disposed at a recessed position on the surface of the power storage element unit 200 in the positive X-axis direction. An elastic member 430 is disposed between the side wall 331 of the third wall member 330 and the power storage unit main body 30. An elastic member 440 is disposed between the bottom wall 332 of the third wall member 330 and the power storage unit main body 30. An elastic member 450 is disposed between the partition wall 340 and the power storage unit main body 30.

[0066] With this configuration, the pair of first wall members 310 sandwich the power storage unit main body 30 in a state of compressing it in the Y-axis direction. The side walls 331 of the second wall member 320 and the third wall member 330 sandwich the power storage unit main body 30 in a state of compressing it in the X-axis direction. The bottom wall 332 and the partition wall 340 of the third wall member 330 sandwich the power storage unit main body 30 in a state of compressing it in the Z-axis direction.

[0067] The connector 500 is a connector that electrically connects the power storage element unit 200 in the power storage unit main body 30 and wiring outside the power storage device 10 (for example, the wiring of an external charger not shown). The connector 500 is electrically connected to the power storage element unit 200 via a main circuit wiring member described later. The connector 500 is also connected to an electronic component (electronic circuit) provided in the electrical component 510 via a control wiring different from the control wiring member 514. The connector 500 is disposed on the partition wall 340, and the end in the positive X-axis direction protrudes from the connector opening 112a of the outer case 100 (see FIGS. 1 and 3, etc.). That is, at least a part of the connector 500 is disposed inside the outer case 100. The connector 500 may not protrude from the connector opening 112a, and all the connectors 500 may be disposed inside the outer case 100.

[0068] The electrical component 510 is an electrical component that is electrically connected to the power storage element unit 200 in the power storage unit main body 30. The electrical component 510 is disposed on the partition wall 340. The electrical component 510 includes an electronic component such as a circuit board, a relay (magnetic contactor), a fuse, and a current sensor (Hall sensor) for monitoring or controlling the state (voltage, temperature, charge / discharge state, etc.) of the power storage element unit 200, and wiring.

[0069] Cover 600 is a cover member that covers the electrical component 510. Cover 600 is disposed on the partition wall 340 so as to cover the electrical component 510 on the partition wall 340. Cover 600 also covers the fixing portion 342, the opening 343, and the opening 344 of the partition wall 340 (see FIG. 3). That is, within the range covered by cover 600, the electrical component 510, and the fixing portion 342, the opening 343, and the opening 344 of the partition wall 340 are disposed. The gap between cover 600 and partition wall 340 is filled by caulking or welding or the like, and waterproofing treatment is performed. Thereby, in a state where the partition wall 340 divides the space inside the outer case 100 vertically, the power storage unit main body 30 is waterproofed, and the electrical component 510 and the like are waterproofed.

[0070] Cover 600 is a box-shaped member and is provided with a wire holding portion 610 on the side surface in the positive X-axis direction. The wire holding portion 610 is a member that allows a wire to be inserted and held. The side surface of cover 600 and the wire holding portion 610 face the connector 500. In each wire holding portion 610, a main circuit wiring member for the positive and negative electrodes for charging, a control wiring member (not shown), and the like are inserted and held. One end of the charging wire is connected to the connector 500, and the other end is connected to the main circuit wiring member inside the cover 600. The wire holding portion 610 has waterproof properties and prevents water from entering the cover 600. The wire holding portion 610 also holds a wire for discharging (not shown). The wire holding portion 610 may hold a wire for both charging and discharging.

[0071] [1.3 Description of the First Fixing Member 700] Next, the first fixing member 700 will be described in detail.

[0072] The first fixing member 700 is a member that is housed in the outer case 100 and fixes the power storage unit 20 and the outer case 100. The first fixing member 700 is fixed to the first wall member 310 of the inner case 300 of the power storage unit 20 and the intermediate member 130 of the outer case 100. As a result, the first fixing member 700 is disposed at a position facing the through-hole 111a of the outer case side wall 111 of the outer case 100 (a position where at least a part of the first fixing member 700 is exposed from the through-hole 111a). In the present embodiment, a plurality of first fixing members 700 are arranged corresponding to the plurality of through-holes 111a of the outer case 100. Specifically, two first fixing members 700 are arranged corresponding to the two through-holes 111a formed in the pair of outer case side walls 111 of the case main body 110.

[0073] As shown in FIG. 2, the first fixing member 700 includes two fixing member main bodies 710 arranged in the X-axis direction and a plurality of reinforcing portions 720 provided on the two fixing member main bodies 710. The two fixing member main bodies 710 are arranged on both sides in the X-axis direction of the column portion 131b of the intermediate member main body 131 of the intermediate member 130. Each fixing member main body 710 is an L-shaped and plate-shaped member extending in the X-axis direction as viewed from the X-axis direction. The reinforcing portion 720 is a triangular and plate-shaped reinforcing rib as viewed from the X-axis direction.

[0074] Each fixing member main body 710 includes a plurality of fixing portions 711 for fixing to the outer case 100 and a plurality of fixing portions 712 for fixing to the power storage unit 20. The fixing portion 711 is disposed on a flat plate portion parallel to the XY plane at the end in the minus Z-axis direction of the fixing member main body 710. The fixing portion 711 is a bolt having a male screw portion and is coupled to a female screw portion formed in the fixing portion 131d of the intermediate member main body 131 of the intermediate member 130. The fixing portion 712 is disposed on a flat plate portion parallel to the XZ plane at the end in the plus Y-axis direction of the fixing member main body 710. The fixing portion 712 is a bolt having a male screw portion and is coupled to a female screw portion formed in the fixing portion 310a of the first wall member 310 of the inner case 300. The reinforcing portion 720 is disposed at a position adjacent in the X-axis direction to each of the fixing portion 711 and the fixing portion 712 having the same position in the X-axis direction.

[0075] [Description of Elastic Member 800 and Gasket 900] Next, the elastic member 800 and the gasket 900 will be described in detail.

[0076] The elastic member 800 is a member disposed between the power storage unit 20 and the outer case bottom wall 113 of the outer case 100. Similar to the elastic member 400, the elastic member 800 is a sheet-like elastic member having functions such as tolerance absorption, vibration suppression, or anti-slip. The elastic member 800 can be formed of any member or the like that can be used for the elastic member 400.

[0077] The gasket 900 is a member disposed between the partition wall 340 of the inner case 300 of the power storage unit 20 and the outer case 100. The gasket 900 is a rectangular annular member disposed along the outer peripheral portion outside the second fixing member 341 on the partition wall 340. Specifically, the gasket 900 is disposed between the partition wall 340 and the weight 120. In the present embodiment, the gasket 900 is divided into four members corresponding to each of the pair of weights 121 and the pair of weights 122, but it may be divided into any number of members or may be formed of one member. The gasket 900 can be formed of any member or the like that can be used for the gasket 133 of the intermediate member 130.

[0078] [Description of Power Storage Element Unit 200] Next, the configuration of the energy storage element unit 200 will be described in detail. FIG. 6 is a perspective view showing the configuration of the energy storage element unit 200 according to the present embodiment. FIG. 6(a) shows an enlarged view of one energy storage element unit 200 shown in FIG. 5, and the energy storage element 210 and the external terminals 250 located inside are indicated by broken lines. FIG. 6(b) is a perspective view showing the end portion of the energy storage element unit 200 in the +Y-axis direction when the energy storage element unit 200 shown in FIG. 6(a) is viewed from the opposite side (+Y-axis direction). Since the plurality of energy storage element units 200 included in the energy storage device 10 (energy storage unit 20, energy storage unit main body 30) all have the same configuration, FIG. 6 shows one energy storage element unit 200, and hereinafter, the configuration of one energy storage element unit 200 will be described in detail.

[0079] The energy storage element unit 200 is a substantially rectangular parallelepiped battery module (battery pack) that can charge electricity from the outside and discharge electricity to the outside. As shown in FIG. 6, the energy storage element unit 200 includes a plurality of energy storage elements 210, a pair of end plates 220, a pair of side plates 230, an exterior member 240, a pair (positive and negative) of external terminals 250, and a pair (positive and negative) of terminal covers 260. In addition to the above configuration, the energy storage element unit 200 also includes a spacer disposed between the energy storage elements 210, a bus bar that connects the terminals 212 of the plurality of energy storage elements 210, and a bus bar frame that positions the bus bar, etc., but illustration and detailed description thereof are omitted.

[0080] In the present embodiment, the depth direction (front-rear direction) of the energy storage element unit 200 is along the Y-axis direction (third direction). The surface of the side plate 230 in the -Y-axis direction in the -Y-axis direction and the surface of the exterior member 240 in the -Y-axis direction are referred to as the front surface of the energy storage element unit 200. The surface of the side plate 230 in the +Y-axis direction in the +Y-axis direction and the surface of the exterior member 240 in the +Y-axis direction are referred to as the rear surface of the energy storage element unit 200. The pair of external terminals 250 are disposed on the front surface of the energy storage element unit 200.

[0081] The energy storage element 210 is a secondary battery (single cell) that can charge and discharge electricity. More specifically, it is a non-aqueous electrolyte secondary battery such as a lithium-ion secondary battery. In the present embodiment, a plurality of energy storage elements 210 are arranged side by side in the Y-axis direction and the Z-axis direction, but the arrangement direction and the number of the energy storage elements 210 are not particularly limited. In the present embodiment, the energy storage element 210 has a rectangular parallelepiped shape (square shape) that is flat in the Z-axis direction, but the shape of the energy storage element 210 is not limited to the rectangular parallelepiped shape, and may be a polygonal prism shape, a cylindrical shape, an elliptical cylindrical shape, an elliptical prism shape, etc. other than the rectangular parallelepiped shape. The energy storage element 210 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 energy storage element 210 may be a primary battery instead of a secondary battery. The energy storage element 210 may be a battery using a solid electrolyte. The energy storage element 210 may be a pouch-type energy storage element.

[0082] The energy storage element 210 includes a container 211 and terminals 212 that are a pair of (positive and negative) electrode terminals. Inside the container 211, an electrode body, a pair of (positive and negative) current collectors, an electrolytic solution (non-aqueous electrolyte), etc. are accommodated, but the illustration and detailed description thereof are omitted. The container 211 includes a container body having an opening formed therein and a lid portion that closes the opening of the container body, and the terminals 212 are arranged in a state of protruding in the negative X-axis direction from the lid portion. The terminals 212 are 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 an energy storage element (power generation element) formed by laminating a positive electrode plate, a negative electrode plate, and a separator.

[0083] A pair of end plates 220 and a pair of side plates 230 are restraining members that sandwich a plurality of power storage elements 210 from both sides in the Z-axis direction, thereby compressing (restraining) each power storage element 210 from both sides in the Z-axis direction. The restraining member is composed of a first restraining member (end plate 220) and a second restraining member (side plate 230). In other words, a pair of end plates 220 and a pair of side plates 230 are holding members that hold a plurality of power storage elements 210. The holding member is composed of a first holding member (end plate 220) and a second holding member (side plate 230). The end plates 220 and the side plates 230 are formed of metal members such as steel or stainless steel from the viewpoint of ensuring strength, etc., but the material is not particularly limited and may be formed of a highly strong insulating member, or an insulating treatment may be applied to the metal member.

[0084] A pair of end plates 220 are plate-shaped and rectangular members that are arranged on both sides of a plurality of power storage elements 210 in the Z-axis direction and sandwich and hold the plurality of power storage elements 210 from both sides in the Z-axis direction. The end plate 220 may be a flat block-shaped member or the like instead of a plate shape. The end plate 220 includes a protruding portion 221 that protrudes in the minus Y-axis direction and a protruding portion 222 that protrudes in the plus Y-axis direction. Concave portions 221a are formed on both sides in the X-axis direction of the protruding portion 221, and concave portions 222a are formed on both sides in the X-axis direction of the protruding portion 222. The end face (front end face) in the minus Y-axis direction of the protruding portion 221 has a front end face 221c that is a flat surface, and the end face (front end face) in the plus Y-axis direction of the protruding portion 222 has a front end face 222c that is a flat surface. In the present embodiment, both of the pair of end plates 220 include protruding portions 221 and concave portions 221a and protruding portions 222 and concave portions 222a having the same configuration.

[0085] The protruding portion 221 is a rectangular portion extending in the X-axis direction that protrudes in the negative Y-axis direction from the substantially central portion in the X-axis direction at the negative Y-axis direction end of the end plate 220. The protruding portion 221 is provided with a fixing portion 221b such as a bolt for fixing the end plate 220 to the side plate 230. The protruding portion 221 protrudes in a predetermined direction (negative Y-axis direction) from the external terminal 250. The protruding portion 222 is a rectangular portion extending in the X-axis direction that protrudes in the positive Y-axis direction from the substantially central portion in the X-axis direction at the positive Y-axis direction end of the end plate 220. The protruding portion 222 is provided with a fixing portion 222b such as a bolt for fixing the end plate 220 to the side plate 230.

[0086] The pair of side plates 230 are plate-shaped and rectangular members arranged on both sides in the Y-axis direction of the plurality of power storage elements 210. The side plates 230 have both ends in the Z-axis direction attached to the ends in the Y-axis direction of the pair of end plates 220, and by connecting the pair of end plates 220, the plurality of power storage elements 210 are constrained. The side plates 230 extend in the Z-axis direction so as to straddle the plurality of power storage elements 210, and apply a constraining force in the Z-axis direction to the plurality of power storage elements 210. The side plates 230 may be long rod-shaped members or the like instead of being plate-shaped.

[0087] The exterior member 240 is a member that covers the X-axis minus direction of a plurality of power storage elements 210 etc., and protects the plurality of power storage elements 210 etc. from external impacts etc. In the present embodiment, the exterior member 240 is a metal member, but it may also be a resin member. At the Z-axis plus direction end of the Y-axis plus direction end of the exterior member 240, an opening 241 through which a control wiring member 514 (see FIG. 8) including wiring etc. for monitoring or controlling the state (voltage, temperature, charge / discharge state, etc.) of the power storage element 210 passes is formed. The opening 241 is arranged on the rear surface, which is on the opposite side of the front surface of the power storage element unit 200 in the Y-axis direction (third direction). The exterior member 240 is attached and fixed to a pair of end plates 220 and a pair of side plates 230. At both ends of the exterior member 240 in the Z-axis direction, recesses 242 extending in the Y-axis direction are formed, and fixing portions 243 with the pair of end plates 220 are arranged in the recesses 242. Thereby, the fixing portions 243 are suppressed from protruding from the outer surface (the end face in the X-axis minus direction) of the exterior member 240. In the present embodiment, the fixing portions 243 do not protrude from the outer surface (the end face in the X-axis minus direction) of the exterior member 240.

[0088] The external terminal 250 is an external terminal that is electrically connected to the terminal 212 of the power storage element 210, charges electricity from the outside, and discharges electricity to the outside. The external terminal 250 is a terminal member different from the terminal 212 of the power storage element 210. The external terminal 250 is formed of a conductive member made of a metal such as aluminum, aluminum alloy, copper, copper alloy, nickel, etc. or a combination thereof, or a conductive member other than metal. In the present embodiment, a pair (positive electrode and negative electrode) of external terminals 250 arranged in the Z-axis direction are arranged at the X-axis minus direction end and both ends in the Z-axis direction of the Y-axis minus direction end of the power storage element unit 200. The external terminal 250 protrudes and is arranged in a predetermined direction (Y-axis minus direction) from the main body portion (the portion where the power storage element 210 is arranged) of the power storage element unit 200. Specifically, the external terminal 250 protrudes in the Y-axis minus direction from the Y-axis minus direction surface of the side plate 230 in the Y-axis minus direction and the Y-axis minus direction surface of the exterior member 240.

[0089] The terminal cover 260 is a cover member for the external terminal 250, which is arranged to cover the external terminal 250 and insulate and protect the external terminal 250. An opening (not shown) through which a conductive member such as a bus bar connected to the external terminal 250 passes is formed in the terminal cover 260. The terminal cover 260 is formed of an insulating member such as polycarbonate (PC), polypropylene (PP), polyethylene (PE), polystyrene (PS), polyphenylene sulfide resin (PPS), polyphenylene ether (PPE (including modified PPE)), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyether ether ketone (PEEK), tetrafluoroethylene·perfluoroalkyl vinyl ether (PFA), polytetrafluoroethylene (PTFE), polyethersulfone (PES), polyamide (PA), ABS resin, or a composite material thereof. The terminal cover 260 may be formed of a metal or the like with insulating coating. The terminal cover 260 thereby protects the external terminal 250 and avoids the external terminal 250 from contacting an external metal member or the like.

[0090] [Explanation of the positional relationship of the components included in the power storage device 10] Next, the positional relationship of the components included in the power storage device 10 will be described in detail. FIG. 7 is a cross-sectional view showing the positional relationship of the components included in the power storage device 10 according to the present embodiment. In FIG. 7, the power storage device 10 is cut along a plane parallel to the XZ plane located between the elastic member 410 in the negative Y-axis direction and the power storage unit main body 30, and the configuration when viewed from the negative Y-axis direction is shown. FIG. 8 is a top view showing the positional relationship of the components included in the power storage device 10 according to the present embodiment. FIG. 8 shows the configuration when viewed from the positive Z-axis direction after removing members (partition wall 340, other electrical components 510, cover 600, etc.) other than the first bus bar 41 and the electrical component 511 among the members located in the positive Z-axis direction relative to the power storage unit main body 30 from the power storage device 10.

[0091] As shown in FIG. 7, the side walls 331 of the second wall member 320 and the third wall member 330 of the inner case 300 sandwich a plurality of power storage element units 200 in the X-axis direction and contact the plurality of power storage element units 200 in the X-axis direction (indirectly through elastic members 420, 430, etc.). The bottom wall 332 and the partition wall 340 of the third wall member 330 sandwich a plurality of power storage element units 200 in the Z-axis direction and contact the plurality of power storage element units 200 in the Z-axis direction (indirectly through elastic members 440, 450). As shown in FIG. 8, the pair of first wall members 310 sandwich a plurality of power storage element units 200 in the Y-axis direction and contact the plurality of power storage element units 200 in the Y-axis direction (indirectly through the elastic member 410).

[0092] The pair of first wall members 310, which are two wall members included in the inner case 300, sandwich the plurality of power storage element units 200 at the position of the protrusion 221 of the end plate 220. That is, as described above, in the power storage element unit 200, the protrusion 221 of the end plate 220 protrudes in the negative Y-axis direction from the external terminal 250. Further, the protrusion 221 protrudes in the negative Y-axis direction from the terminal cover 260 (see FIG. 12). In the negative Y-axis direction of the protrusion 221, the first wall member 310 is disposed, and the protrusion 221 contacts the first wall member 310 in the Y-axis direction (indirectly through the elastic member 410). That is, the external terminal 250 and the terminal cover 260 are disposed spaced apart from the first wall member 310 without contacting the first wall member 310.

[0093] Similarly, a pair of first wall members 310, which are two wall members, sandwich a plurality of power storage element units 200 at the position of the protruding portions 222 of the end plate 220. That is, in the +Y-axis direction of the protruding portion 222 protruding in the +Y-axis direction, the other first wall member 310 is arranged, and the protruding portion 222 contacts the first wall member 310 in the Y-axis direction (indirectly through the other elastic member 410). In this way, the pair of first wall members 310 sandwich the plurality of power storage element units 200 in the Y-axis direction at the positions of the protruding portions 221 and 222 in the Z-axis direction. The protruding portion 221 has a flat tip surface 221c in surface contact with one of the first wall members 310, and the protruding portion 222 has a flat tip surface 222c in surface contact with the other first wall member 310.

[0094] With such a configuration, a recess formed by connecting two recesses 221a is formed between the two external terminals 250 provided in two adjacent power storage element units 200 in the Z-axis direction. A bus bar or wiring or the like connected to the external terminal 250 passes through the recess 221a. That is, the recess 221a is formed in a size through which the bus bar or wiring or the like can pass.

[0095] As described above, the power storage unit main body 30 includes six power storage element unit groups 31 arranged in the X-axis direction (second direction), and each of the plurality of power storage element unit groups 31 includes two power storage element units 200 arranged in the Z-axis direction (first direction). As shown in FIG. 6, each of the plurality of power storage element units 200 includes a pair of external terminals 250 arranged in the Z-axis direction (first direction). As shown in FIG. 7, in each power storage element unit group 31, by setting the arrangement direction (stacking direction) of the power storage element units 200 included in the power storage element unit group 31 and the arrangement direction of the pair of external terminals 250 of the power storage element units 200 in the same direction (Z-axis direction), four external terminals 250 are arranged in the Z-axis direction. In the power storage unit main body 30, the power storage element unit groups 31 are arranged in the direction (X-axis direction) intersecting the direction in which the pair of external terminals 250 are arranged, so that the external terminals 250 included in each of the six power storage element unit groups 31 are arranged in the X-axis direction. More specifically, the external terminals 250 of the same potential in each power storage element unit group 31 are arranged in the X-axis direction at the same position in the Z-axis direction.

[0096] The plurality of power storage element unit groups 31 are connected in parallel. Specifically, the power storage unit main body 30 further includes a first bus bar 41 and a second bus bar 42 which are a pair of bus bars 40. The pair of bus bars 40 (the first bus bar 41 and the second bus bar 42) extend in the X-axis direction (second direction) and connect the plurality of power storage element unit groups 31 in parallel. The plurality of power storage element units 200 included in each of the plurality of power storage element unit groups 31 are connected in series. Specifically, the power storage element unit group 31 further includes a third bus bar 43. The third bus bar 43 extends in the Z-axis direction and connects the plurality of power storage element units 200 in series. The third bus bar 43 passes through the recess 221a of the end plate 220 of the two power storage element units 200. The first bus bar 41, the second bus bar 42, and the third bus bar 43 are formed of a metal conductive member such as aluminum, aluminum alloy, copper, copper alloy, nickel, or a combination thereof, or a conductive member other than metal. Since the first bus bar 41, the second bus bar 42, and the third bus bar 43 are plate-like members, the connection work is easier than that of a cable (electric wire) or the like.

[0097] In this embodiment, the first bus bar 41 is connected to each power storage element unit group 31 via the first conductive member 513. That is, the power storage unit 20 includes the first conductive members 513 connected to each of the plurality of power storage element unit groups 31. The first conductive member 513 is connected to the external terminal 250 at the plus Z-axis direction end among the external terminals 250 of the power storage element unit 200 included in each power storage element unit group 31. Further, each first conductive member 513 is electrically connected to the first bus bar 41. Specifically, the first conductive member 513 is connected to the first bus bar 41 via the electrical component 511. More specifically, the first conductive member 513 passes through the recess 221a of the power storage element unit 200 located in the plus Z-axis direction of the external terminal 250 from the external terminal 250, penetrates the opening 343 of the partition wall 340, and is connected to the electrical component 511. In this way, the first conductive member 513 electrically connects the power storage element unit 200 and the electrical component 511. Thereby, the first conductive member 513 is connected to the first bus bar 41 connected to the electrical component 511. In this embodiment, the first conductive member 513 is a cable (electric wire), but may also be a conductive member such as a bus bar. The electrical component 511 is a magnetic contactor (electromagnetic contactor, MC), but may also be a fuse or the like. When the first conductive member 513 passes through the electrical component 512, the current flowing through the first conductive member 513 is measured. The electrical component 512 is a Hall sensor.

[0098] With such a configuration, as shown in FIG. 8, the first bus bar 41 is arranged at a position in the plus Z-axis direction of the plurality of power storage element unit groups 31 and overlapping the plurality of power storage element unit groups 31 when viewed from the Z-axis direction. In this way, the plurality of power storage element unit groups 31 are connected in parallel by the bus bar 40 (first bus bar 41) arranged at a position in the Z-axis direction (first direction) of the plurality of power storage element unit groups 31 and overlapping the plurality of power storage element unit groups 31 when viewed from the Z-axis direction (first direction).

[0099] One and the other of the main circuit wiring members (the positive electrode wiring member and the negative electrode wiring member) of the positive electrode and the negative electrode, through which the current flowing through each power storage element unit group 31 is integrated, are connected to the first bus bar 41 and the second bus bar 42. In the present embodiment, the first wiring member 515, which is the main circuit wiring member (positive electrode wiring member) of the positive electrode, is connected to the first bus bar 41. The second wiring member 516, which is the main circuit wiring member (negative electrode wiring member) of the negative electrode, is connected to the second bus bar 42. The positive electrode wiring member and the negative electrode wiring member are each composed of a plurality of wiring members, penetrate through the wire holding portion 610 provided in the cover 600, and are connected to the connector 500. The wire holding portion 610 is configured to be able to seal between the wire holding portion 610 and the main circuit wiring member, and between the wire holding portion 610 and the cover 600. The wire holding portion 610 is a cable ground, but may also have a structure that fills the gap with caulking or the like.

[0100] As shown in FIG. 8, the power storage unit 20 further includes a control wiring member 514 for controlling at least one power storage element unit 200 among the plurality of power storage element units 200. The control wiring member 514 is derived from the rear surface of the power storage element unit 200, which is located on the opposite side of a pair of external terminals 250 of the plurality of power storage element units 200 in the Y-axis direction (the third direction intersecting the first direction and the second direction). In the present embodiment, the control wiring member 514 is provided with harness connectors (not shown) at both ends and is connected to the mating harness connector inside the opening 241 on the rear surface of the power storage element unit 200. Thereby, in each power storage element unit 200, the control wiring member 514 is derived from the opening 241 formed at the Y-axis plus direction end of the exterior member 240. The control wiring member 514 derived from the opening 241 is connected to the connector 500 through the electronic components (electronic circuits) and wiring etc. provided in the electrical component 510 (such as the wiring penetrating through the cover 600). In the present embodiment, the control wiring member 514 is a cable (wire) including various wirings such as wiring for monitoring or controlling the state (voltage, temperature, charge and discharge state, etc.) of the power storage element 210, wiring for controlling the electrical component 510, and wiring for communication, but may also be a conductive member such as a bus bar.

[0101] As shown in FIG. 7, the partition wall 340 divides the space inside the outer case 100 into a first space S1 and a second space S2 arranged in the Z-axis direction. The power storage element unit 200 (power storage unit main body 30) is arranged in the first space S1. At least a part of the connector 500 is arranged in the second space S2. Further, in the second space S2, an electrical component 510 and a cover 600 covering the electrical component 510 are arranged.

[0102] [Explanation of the electrical connection configuration of the power storage unit 20] Next, the electrical connection configuration of the power storage element unit 200 included in the power storage unit 20 will be described in detail. FIG. 9 is a schematic diagram showing the electrical connection configuration of the power storage element unit 200 according to the present embodiment.

[0103] As described above, a plurality of power storage element unit groups 31 arranged in the X-axis direction are connected in parallel by a pair of bus bars 40 (first bus bar 41 and second bus bar 42). A plurality of power storage element units 200 arranged in the Z-axis direction included in each power storage element unit group 31 are connected in series by a third bus bar 43. As a result, in each power storage element unit group 31, a plurality of external terminals 250 are arranged in the Z-axis direction. In the present embodiment, as shown in FIG. 9, each power storage element unit group 31 includes external terminals 251, 252, 253, and 254, which are four external terminals arranged in the Z-axis direction.

[0104] The first bus bar 41 is a plate-like member parallel to the XY plane and extending in the X-axis direction. The first bus bar 41 is electrically connected to the external terminal 251 at the Z-axis plus direction end of each power storage element unit group 31. The second bus bar 42 is a plate-like member parallel to the XZ plane and extending in the X-axis direction. The second bus bar 42 is connected (directly connected) to the external terminal 254 at the Z-axis minus direction end of each power storage element unit group 31. The third bus bar 43 is a plate-like member parallel to the XZ plane and extending in the Z-axis direction. The third bus bar 43 is connected (directly connected) to two adjacent external terminals 252 and 253 in the Z-axis direction of two power storage element units 200 in each power storage element unit group 31.

[0105] In this embodiment, the first bus bar 41 and the second bus bar 42 are bus bars having the same shape and the same size. The first bus bar 41 has a length corresponding to the width dimension of the power storage unit main body 30 in the arrangement direction (X-axis direction) of the power storage element unit group 31, which is 5L + α in FIG. 9. The same applies to the second bus bar 42. L is the same length as the width dimension of the power storage element unit 200 in the X-axis direction. If the connection (such as bolt fastening) between the first bus bar 41 and the first conductive member 513 can be made and the lengths of the respective first conductive members 513 can be made equal, L may be shorter or longer than the width dimension of the power storage element unit 200 in the X-axis direction. The first bus bar 41 and the second bus bar 42 may have different shapes or sizes. Each third bus bar 43 is a bus bar having the same shape and the same size, but may have different shapes or sizes.

[0106] Among the plurality of external terminals 250 provided in each power storage element unit group 31, the external terminals 250 located at the outermost ends (both ends) in the current path are referred to as series ends. In this embodiment, among the external terminals 251, 252, 253, and 254, the external terminal 251 at the Z-axis plus direction end and the external terminal 254 at the Z-axis minus direction end are series ends. This external terminal 251 is also referred to as the first terminal 251, and the external terminal 254 is also referred to as the second terminal 254. That is, each of the plurality of power storage element unit groups 31 includes a first terminal 251 that is one series end and a second terminal 254 that is the other series end.

[0107] Each first conductive member 513 has one end connected to the first terminal 251 for each of the plurality of power storage element unit groups 31, and the other end electrically connected to the first bus bar 41. The second bus bar 42 is connected (directly connected) to the second terminal 254 of each power storage element unit group 31. For each of the plurality of power storage element unit groups 31, a third bus bar 43 is connected (directly connected) to the external terminal 252 and the external terminal 253. A first wiring member 515 is connected to the first bus bar 41, and a second wiring member 516 is connected to the second bus bar 42. That is, the power storage unit 20 includes a first wiring member 515 and a second wiring member 516. The first wiring member 515 and the second wiring member 516 are one and the other of a positive electrode wiring member and a negative electrode wiring member in which currents flowing through each power storage element unit group 31 are integrated. In the present embodiment, the first wiring member 515 is a positive electrode wiring member (main circuit wiring member of the positive electrode), and the second wiring member 516 is a negative electrode wiring member (main circuit wiring member of the negative electrode). The first wiring member 515 and the second wiring member 516 are conductive members such as a bus bar or a cable (electric wire).

[0108] The first wiring member 515 is connected to the first end portion 41a of the first bus bar 41. The first end portion 41a is located in a range from the parallel connection location 41b, which is the most in the negative X-axis direction (one side of the second direction), among the parallel connection locations 41b to 41g of the first bus bar 41 with the plurality of power storage element unit groups 31, to the edge 41h of the first bus bar 41 in the negative X-axis direction (one side of the second direction). The parallel connection locations 41b to 41g are connection locations of the first bus bar 41 with the plurality of power storage element unit groups 31 for connecting the plurality of power storage element unit groups 31 in parallel. Since each power storage element unit group 31 is connected to each first conductive member 513, the parallel connection locations 41b to 41g are connection locations of the first bus bar 41 with the plurality of first conductive members 513. Further, since the first conductive member 513 is connected to the first bus bar 41 via the electrical component 511, the parallel connection locations 41b to 41g are connection locations of the first bus bar 41 with the plurality of electrical components 511.

[0109] In the present embodiment, the first end portion 41a is the end portion of the first bus bar 41 in the minus X-axis direction. The parallel connection portion 41b is the parallel connection portion at the most minus X-axis direction end among the parallel connection portions 41b to 41g. The edge 41h is the edge of the first bus bar 41 in the minus X-axis direction. In the present embodiment, the first end portion 41a is arranged at the same position as the parallel connection portion 41b in the X-axis direction, but may be arranged in the minus X-axis direction rather than the parallel connection portion 41b. The first end portion 41a may be the end portion of the first bus bar 41 in the plus X-axis direction, and the first wiring member 515 may be connected to the end portion of the first bus bar 41 in the plus X-axis direction. That is, the first end portion 41a may be located in the range from the parallel connection portion 41g at the most plus X-axis direction end among the parallel connection portions 41b to 41g to the edge 41i of the first bus bar 41 in the plus X-axis direction.

[0110] The second wiring member 516 is connected to the second end portion 42a of the second bus bar 42. The second end portion 42a is located in the range from the parallel connection portion 42b at the most plus X-axis direction (the other side of the second direction) among the parallel connection portions 42b to 42g of the second bus bar 42 with the plurality of power storage element unit groups 31 to the edge 42h of the second bus bar 42 in the plus X-axis direction (the other side of the second direction). The parallel connection portions 42b to 42g are the connection portions of the second bus bar 42 for connecting the plurality of power storage element unit groups 31 with the plurality of power storage element unit groups 31.

[0111] In the present embodiment, the second end portion 42a is the end portion of the second bus bar 42 in the +X-axis direction. The parallel connection point 42b is the parallel connection point at the most +X-axis direction end among the parallel connection points 42b to 42g. The edge 42h is the edge of the second bus bar 42 in the +X-axis direction. In the present embodiment, the second end portion 42a is arranged at the same position as the parallel connection point 42b in the X-axis direction, but may be arranged in the +X-axis direction relative to the parallel connection point 42b. The second end portion 42a may be the end portion of the second bus bar 42 in the -X-axis direction, and the second wiring member 516 may be connected to the end portion of the second bus bar 42 in the -X-axis direction. That is, the second end portion 42a may be located in the range from the parallel connection point 42g at the most -X-axis direction end among the parallel connection points 42b to 42g to the edge 42i of the second bus bar 42 in the -X-axis direction.

[0112] [Description of Effects] As described above, according to the power storage device 10 according to the embodiment of the present invention, a plurality of power storage element units 200 each including a plurality of power storage elements 210 and a pair of external terminals 250 arranged in the Z-axis direction (first direction) are arranged in the Z-axis direction (first direction) and connected in series to form a power storage element unit group 31. The plurality of power storage element unit groups 31 are arranged in the X-axis direction (second direction) and connected in parallel. Thereby, a plurality of power storage element units 200 each including a plurality of power storage elements 210 can be arranged so as to be easily connected in series and in parallel, and the connection form can be made into a simple configuration. By making the connection form into a simple configuration, when the power storage unit main body 30 is accommodated in a narrow space such as the inner case 300, wiring can be performed with high space efficiency.

[0113] The plurality of power storage element unit groups 31 can be easily connected in parallel by a pair of bus bars 40 (the first bus bar 41 and the second bus bar 42).

[0114] Connect a first conductive member 513 to a first terminal 251 which is one series end of each energy storage element unit group 31, electrically connect each first conductive member 513 to a first bus bar 41, and connect a second bus bar 42 to a second terminal 254 which is the other series end of each energy storage element unit group 31. That is, connect the first bus bar 41 to the first terminal 251 of each energy storage element unit group 31 via the first conductive member 513. Thereby, the degree of freedom in the arrangement position of the first bus bar 41 can be improved, such as being able to arrange the first bus bar 41 on a side different from the second bus bar 42 with respect to the plurality of energy storage element unit groups 31. Electrical components such as an electrical component 511 (magnetic contactor) and an electrical component 512 (Hall sensor) can be arranged between the energy storage element unit group 31 and the first bus bar 41.

[0115] By connecting a first wiring member 515 and a second wiring member 516 (main circuit wiring members), which are one and the other of the positive electrode wiring member and the negative electrode wiring member, to the end of the bus bar 40, it is possible to suppress the main circuit wiring members from interfering with the energy storage element unit group 31 and make it easier to arrange the main circuit wiring members.

[0116] The first end portion 41a is located at the end portion of the first bus bar 41 in the minus X-axis direction (one side of the second direction), and the second end portion 42a is located at the end portion of the second bus bar 42 in the plus X-axis direction (the other side of the second direction). Thereby, the first wiring member 515 is connected to the end portion of the first bus bar 41 in the minus X-axis direction (one side of the second direction), and the second wiring member 516 is connected to the end portion of the second bus bar 42 in the plus X-axis direction (the other side of the second direction). In this way, when viewed from the minus Y-axis direction, the connection location (the first end portion 41a) of the first wiring member 515 and the connection location (the second end portion 42a) of the second wiring member 516 are in a diagonal positional relationship. In such a configuration, in each power storage element unit group 31, the sum of the wiring distance (the length of the current path) from the first terminal 251 of the power storage element unit group 31 to the first wiring member 515 and the wiring distance (the length of the current path) from the second terminal 254 of the power storage element unit group 31 to the second wiring member 516 can be made equal (can be made into equal-length wiring). Specifically, in FIG. 9, for the second power storage element unit group 31 from the end portion in the minus X-axis direction, the wiring distance to the first wiring member 515 is L, and the wiring distance to the second wiring member 516 is 4L. Therefore, the total wiring distance is 5L. For the third power storage element unit group 31 from the end portion in the minus X-axis direction, the wiring distance to the first wiring member 515 is 2L, and the wiring distance to the second wiring member 516 is 3L. Therefore, the total wiring distance is 5L. The same applies to the other power storage element unit groups 31. In this way, for each power storage element unit group 31, the total wiring distance is 5L. The wiring distance here (5L in this example) is not exact, and there may be some difference in length. Assuming that the first conductive members 513 in each power storage element unit group 31 are the same member and have the same wiring length, they are not included in the above wiring distance (the length of the current path). By making the cross-sectional areas of the first bus bar 41 and the second bus bar 42 the same, the resistance values in each current path can be made equal.

[0117] By leading out the control wiring member 514 from the side opposite to the external terminal 250 of the power storage element unit 200 in the Y-axis direction (third direction), it is possible to suppress the control wiring member 514 from interfering with the wiring member (main circuit wiring member) connected to the external terminal 250. By arranging the control wiring member 514 and the main circuit wiring member separately, the influence of noise from the main circuit wiring member on the control wiring member 514 can be reduced.

[0118] By arranging the first bus bar 41 for connecting a plurality of power storage element unit groups 31 in parallel at a position overlapping the plurality of power storage element unit groups 31 when viewed from the Z-axis direction (first direction), the first bus bar 41 can be arranged on a side different from the second bus bar 42 with respect to the plurality of power storage element unit groups 31, etc., and the degree of freedom in arranging the first bus bar 41 can be improved. When arranging electrical components such as the electrical component 511 (magnetic contactor) and the electrical component 512 (Hall sensor) between the first bus bar 41 and the power storage element unit group 31, the first bus bar 41 can be arranged at an appropriate position.

[0119] [Description of Modification Example 6] As described above, the power storage device 10 according to the embodiment of the present invention has been described, but the present invention is not limited to this embodiment. The embodiments disclosed this time are illustrative in all respects, and the scope of the present invention includes all modifications within the meaning and scope equivalent to the claims.

[0120] In the above embodiment, the first bus bar 41 is connected (indirectly connected) to the first terminal 251 of each power storage element unit group 31 via the first conductive member 513, and the second bus bar 42 is connected (directly connected) to the second terminal 254 of each power storage element unit group 31, but it is not limited to this. FIG. 10 is a schematic diagram showing the electrical connection configuration of the power storage element unit 200 according to Modification Example 1 of the present embodiment. FIG. 11 is a schematic diagram showing the electrical connection configuration of the power storage element unit 200 according to Modification Example 2 of the present embodiment. FIGS. 10 and 11 are diagrams corresponding to FIG. 9.

[0121] (Modification Example 1) As shown in FIG. 10, in Modification 1, the first conductive member 513 in the above embodiment is not arranged. That is, the first bus bar 41 is connected (directly connected) to the first terminal 251 of each power storage element unit group 31, and the second bus bar 42 is connected (directly connected) to the second terminal 254 of each power storage element unit group 31. The first wiring member 515 is connected to the first end portion 41a of the first bus bar 41. The first end portion 41a is located in the range from the parallel connection portion 41b, which is the most minus X-axis direction (one side of the second direction) among the parallel connection portions 41b to 41g of the first bus bar 41 with the plurality of power storage element unit groups 31, to the edge 41h of the first bus bar 41 in the minus X-axis direction (one side of the second direction). The parallel connection portions 41b to 41g are connection portions of the first bus bar 41 that connects the plurality of power storage element unit groups 31 in parallel. In this modification, similar to the above embodiment, the first end portion 41a may be an end portion of the first bus bar 41 in the plus X-axis direction, and the first wiring member 515 may be connected to the end portion of the first bus bar 41 in the plus X-axis direction. Since the other configurations of this modification are the same as those of the above embodiment, detailed description is omitted.

[0122] As described above, according to the power storage device 10 according to this modification, the same effects as those of the above embodiment can be achieved. In particular, in this modification, by connecting (directly connecting) the first bus bar 41 to the first terminal 251, which is one series end of each power storage element unit group 31, and connecting (directly connecting) the second bus bar 42 to the second terminal 254, which is the other series end of each power storage element unit group 31, the plurality of power storage element unit groups 31 can be easily connected in parallel.

[0123] (Modification 2) As shown in FIG. 11, in Modification 2, in addition to the configuration of the above-described embodiment, a second conductive member 517 is arranged. That is, the first bus bar 41 is connected (indirectly connected) to the first terminals 251 of each power storage element unit group 31 via the first conductive members 513, and the second bus bar 42 is connected (indirectly connected) to the second terminals 254 of each power storage element unit group 31 via the second conductive members 517. The second conductive members 517 in each power storage element unit group 31 are the same members and have the same wiring length. Specifically, for each of the plurality of power storage element unit groups 31, the first conductive members 513 are connected to the first terminals 251, and the second conductive members 517 are connected to the second terminals 254. Each first conductive member 513 is electrically connected to the first bus bar 41, and each second conductive member 517 is electrically connected to the second bus bar 42. The configuration in which the first conductive member 513 is connected to the first bus bar 41 is the same as the configuration in the above-described embodiment.

[0124] The second conductive member 517 is a cable (electric wire), but may also be a conductive member such as a bus bar. The second conductive member 517 may be connected to the second bus bar 42 via an electrical component, or may be directly connected to the second bus bar 42. The second bus bar 42 may be arranged at a position overlapping the plurality of power storage element unit groups 31 when viewed from the Z-axis direction (first direction). In this modification, similar to the above-described embodiment, the second end portion 42a may be an end portion of the second bus bar 42 in the minus X-axis direction, and the second wiring member 516 may be connected to the end portion of the second bus bar 42 in the minus X-axis direction. Since the other configurations of this modification are the same as those of the above-described embodiment, detailed description thereof is omitted.

[0125] As described above, according to the power storage device 10 according to this modification, the same effects as those of the above-described embodiment can be achieved. In particular, in this modification, the degrees of freedom in the arrangement of both the first bus bar 41 and the second bus bar 42 can be improved.

[0126] In the above-described Modification 2, the first bus bar 41 may be connected (directly connected) to the first terminal 251 of each power storage element unit group 31, and the second bus bar 42 may be connected (indirectly connected) to the second terminal 254 of each power storage element unit group 31 via the second conductive member 517.

[0127] (Other Modifications) In the above-described embodiment, the plurality of power storage element units 200 are connected by bus bars (the first bus bar 41, the second bus bar 42, and the third bus bar 43), but may be connected by a conductive member other than a bus bar such as a cable (electric wire). Similarly, in the above-described embodiment, the plurality of power storage element unit groups 31 are connected in parallel by bus bars (the first bus bar 41 and the second bus bar 42) extending in the X-axis direction (second direction), but may be connected in parallel by a conductive member other than a bus bar such as a cable (electric wire). The bus bar does not necessarily need to extend in the second direction. The first conductive member 513 and / or the second conductive member 517 may be directly connected to the electrical component without using a bus bar. That is, the power storage device 10 only needs to include at least one bus bar that extends in the X-axis direction (second direction) and connects the plurality of power storage element unit groups 31 in parallel. Thereby, on one of the positive electrode and the negative electrode sides, simple parallel connection by a bus bar is performed, while on the other electrode side, various connection forms can be supported. Alternatively, the power storage device 10 may not include a bus bar and may connect the plurality of power storage element unit groups 31 in parallel by a conductive member other than a bus bar.

[0128] In the above-described embodiment, the first wiring member 515 is connected to the end portion of the first bus bar 41, but may be connected to any position of the first bus bar 41, such as the central portion of the first bus bar 41. Similarly, the second wiring member 516 may be connected to any position of the second bus bar 42.

[0129] In the above-described embodiment, the control wiring member 514 is led out from the side opposite to the external terminal 250 of the power storage element unit 200 in the Y-axis direction, but may be led out from the same side as the external terminal 250.

[0130] In the above embodiment, the first bus bar 41 is arranged at a position overlapping with a plurality of power storage element unit groups 31 when viewed from the Z-axis direction. However, it may be arranged at a position not overlapping with the plurality of power storage element unit groups 31 when viewed from the Z-axis direction.

[0131] In the above embodiment, the posture (orientation) in which the power storage element unit 200 is arranged is not limited. In the power storage element unit 200, the external terminal 250 may be arranged to protrude in the +Y-axis direction, or may be arranged to protrude in the X-axis direction or the Z-axis direction. The pair of end plates 220 may be arranged to face each other in the X-axis direction, or may be arranged to face each other in the Y-axis direction. That is, the power storage unit main body 30 may be arranged such that the direction in which the external terminal 250 protrudes is the +Y-axis direction, or may be arranged such that it is the X-axis direction or the Z-axis direction.

[0132] In the above embodiment, the power storage element unit 200 may include a box body (container) constituting an exterior body instead of, or in addition to, the end plates 220 and the side plates 230.

[0133] In the above embodiment, the partition wall 340 is a wall that partitions the space inside the outer case 100. However, it may not have the function of partitioning the space inside the outer case 100. In the above embodiment, the partition wall 340 is a part of the inner case 300. However, the partition wall 340 may be a member different from the inner case 300. In this case, the power storage device 10 may not include the inner case 300.

[0134] In the above embodiment, the power storage device 10 is not limited to having all the above-described configurations, such as not having to include the elastic member 800.

[0135] The forms constructed by arbitrarily combining the above embodiment and the above modification examples are also included within the scope of the present invention.

Industrial Applicability

[0136] The present invention can be applied to a power storage device including a power storage element such as a secondary battery.

Explanation of Signs

[0137] 10 Power storage device 20 Power storage unit 30 Power storage unit main body 31 Power storage element unit group 40 Bus bar 41 First bus bar 41a First end 41b~41g, 42b~42g Parallel connection points 41h, 41i, 42h, 42i Edges 42 Second bus bar 42a Second end 43 Third bus bar 100 Outer case 100a, 111b, 112b, 241, 343, 344 Openings 110 Case main body 120, 121, 122 Weights 130 Intermediate member 140 Cover member 200 Power storage element unit 210 Power storage element 220 End plate 230 Side plate 250, 252, 253 External terminals 251 External terminal (first terminal) 254 External terminal (second terminal) 260 Terminal cover 300 Inner case 310 First wall member 320 Second wall member 330 Third wall member 340 Partition wall 341 Second fixing member 400, 410, 420, 421, 430, 440, 450, 800 Elastic members 500 Connector 510, 511, 512 Electrical components 513 First conductive member 514 Control wiring member 515 First wiring member 516 Second wiring member 517 Second conductive member 600 Cover 700 First fixing member

Claims

1. A power storage device comprising a plurality of power storage element unit groups, each of the plurality of power storage element unit groups comprising a plurality of power storage element units arranged in a first direction, each of the plurality of power storage element units comprising a plurality of power storage elements and a pair of external terminals arranged in the first direction, the plurality of power storage element unit groups being arranged in a second direction intersecting the first direction, the plurality of power storage element units included in each of the plurality of power storage element unit groups being connected in series, the plurality of power storage element unit groups being connected in parallel. A power storage device.

2. The power storage device according to claim 1, further comprising at least one bus bar extending in the second direction and connecting the plurality of power storage element unit groups in parallel. The power storage device according to claim 1.

3. The power storage device according to claim 2, further comprising a first bus bar and a second bus bar, which are a pair of the bus bars extending in the second direction and connecting the plurality of power storage element unit groups in parallel. The power storage device according to claim 2.

4. Each of the plurality of power storage element unit groups comprises a first terminal which is one series end and a second terminal which is the other series end, the first bus bar being connected to the first terminals of each of the power storage element unit groups, the second bus bar being connected to the second terminals of each of the power storage element unit groups. The power storage device according to claim 3.

5. Each of the plurality of power storage element unit groups comprises a first terminal which is one series end and a second terminal which is the other series end, the power storage device comprising a first conductive member connected to the first terminals for each of the plurality of power storage element unit groups, each of the first conductive members being electrically connected to the first bus bar, the second bus bar being connected to the second terminals of each of the power storage element unit groups. The power storage device according to claim 3.

6. The power storage device according to any one of claims 3 to 5, further comprising a first wiring member and a second wiring member, which are one and the other of a positive electrode wiring member and a negative electrode wiring member in which currents flowing through each of the power storage element unit groups are integrated, the first wiring member being connected to a first end portion of the first bus bar, the second wiring member being connected to a second end portion of the second bus bar. The power storage device according to any one of claims 3 to 5.

7. The first end portion is located in a range from a parallel connection location on one side in the second direction of the plurality of parallel connection locations of the first bus bar with the plurality of power storage element unit groups to an edge on one side in the second direction of the first bus bar. The second end portion is located in a range from the parallel connection point on the other side in the second direction among the parallel connection points of the plurality of power storage element unit groups in the second bus bar to the edge on the other side in the second direction of the second bus bar. The power storage device according to claim 6.

8. The power storage device further includes a control wiring member for controlling at least one power storage element unit among the plurality of power storage element units. The control wiring member is led out from the side opposite to the pair of external terminals of the plurality of power storage element units in a third direction intersecting the first direction and the second direction. The power storage device according to any one of claims 1 to 5.

9. The plurality of power storage element unit groups are connected in parallel by a bus bar that is located at the position of the plurality of power storage element unit groups in the first direction and overlaps the plurality of power storage element unit groups when viewed from the first direction. The power storage device according to any one of claims 1 to 5.

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