Power storage device

Abstract

This power storage device includes: a module in which a plurality of rectangular parallelepiped power storage elements having a dimension in a first direction larger than a dimension in a second direction orthogonal to the first direction are stacked in a third direction orthogonal to the first direction and the second direction; an end member disposed to face an end surface of the module in the third direction; and a terminal block electrically connected to terminals of the plurality of power storage elements. The end member is provided with a recess. The recess is recessed further inward in the second direction than an end surface of the end member in the second direction when viewed from the third direction, and is recessed further inward in the third direction than an end surface of the end member in the third direction. At least a portion of the terminal block is accommodated in the recess.

Description

Power Storage Device

[0001] The present invention relates to a power storage device. This application claims priority based on Japanese Patent Application No. 2025-051575 filed in Japan on March 26, 2025, the content of which is incorporated herein by reference.

[0002] For example, Patent Document 1 and Patent Document 2 disclose a power storage device. The power storage device disclosed in Patent Document 1 includes a plurality of power storage elements and external terminals connected to the terminals of the plurality of power storage elements. In Patent Document 1, a terminal block provided with such external terminals is arranged at ends in the stacking direction of the plurality of power storage elements.

[0003] WO 2020 / 137410, JP 2019-169389 A

[0004] The present invention provides a power storage device that can improve the protection performance of a terminal block connected to the terminals of a plurality of power storage elements.

[0005] As a solution to the above problem, an embodiment of the present invention has the following configuration. A power storage device according to one aspect of the present invention comprises: a module in which a plurality of rectangular parallelepiped power storage elements, each having a dimension in a first direction larger than the dimension in a second direction orthogonal to the first direction, are stacked and arranged in a third direction orthogonal to both the first direction and the second direction; an end member arranged opposite to an end face of the module in the third direction; and a terminal block electrically connected to terminals of the plurality of power storage elements, wherein the end member is provided with a recess, the recess is recessed inward in the second direction from an end face in the second direction when viewed from the third direction, and is also recessed inward in the third direction from an end face of the end member in the third direction, and at least a part of the terminal block is accommodated in the recess.

[0006] According to an embodiment of the present invention, it is possible to improve the protection performance of the terminal block connected to the terminals of the plurality of power storage elements.

[0007] This is an exploded perspective view showing the schematic configuration of the energy storage device according to this embodiment. This is a perspective view of the energy storage unit of the above energy storage device. This is a front view of the energy storage unit of Figure 2. This is a top view of the energy storage unit of Figure 2. This is a bottom view of the energy storage unit of Figure 2. This is a left side view of the energy storage unit of Figure 2. This is a right side view of the energy storage unit of Figure 2. This is a right side view of the energy storage unit of Figure 2.

[0008] (1) An energy storage device according to one aspect of the present invention comprises a module in which a plurality of rectangular parallelepiped energy storage elements, the dimensions in a first direction being larger than the dimensions in a second direction perpendicular to the first direction, are stacked in a third direction perpendicular to the first and second directions; an end member positioned opposite the end face of the module in the third direction; and a terminal block electrically connected to the terminals of the plurality of energy storage elements, wherein the end member is provided with a recess, the recess is recessed inward in the second direction from the end face in the second direction as viewed from the third direction, and recessed inward in the third direction from the end face of the end member in the third direction, and at least a part of the terminal block is housed in the recess.

[0009] According to the energy storage device described in (1) above, a recess is provided in the end member. Furthermore, at least a portion of the terminal block electrically connected to the terminals of the multiple energy storage elements is housed in the recess. Therefore, when an external force is applied to the energy storage device from the outside, the external force acting on the terminal block can be suppressed. Accordingly, according to the energy storage device described in (1) above, the protective performance of the terminal block connected to the terminals of the multiple energy storage elements can be improved.

[0010] (2) In the energy storage device described in (1) above, the terminal block is located on the central side of the module in the third direction, rather than on the outermost part of the end member in the third direction.

[0011] According to the energy storage device described in (2) above of the present invention, it is possible to suppress the transmission of external forces input from the outside in the third direction to the end member and then to the terminal block. Therefore, according to the energy storage device described in (2) above, the protective performance of the terminal block can be further improved.

[0012] (3) The energy storage device described in (1) or (2) above is provided with a side member that is positioned opposite to the first surface of the energy storage element which is perpendicular to the first direction, the side member having at least one fixing portion that is fixed to the end member, the first fixing portion which is one of the fixing portions being positioned in the first direction toward the central part of the energy storage element which is relative to the first surface of the energy storage element, and the terminal block being positioned in the first direction between the first fixing portion and the end of the end member in the first direction.

[0013] According to the energy storage device described in (3) above of the present invention, the terminal block is located inward in the first direction from the end of the end member in the first direction. Therefore, it is possible to suppress the transmission of external forces input from the outside in the first direction to the end member and then to the terminal block. Accordingly, according to the energy storage device described in (3) above of the present invention, the protective performance of the terminal block can be further improved.

[0014] (4) In the energy storage device described in (3) above, the first fixing portion is located on one end side of the end member in the second direction when viewed from the third direction, the side member has a second fixing portion which is the fixing portion located on the other end side of the end member in the second direction and at the end of the end member in the first direction when viewed from the third direction, the end member has a frame portion connecting the first fixing portion and the second fixing portion, and the terminal block is located on the inside of the outer edge of the end member and on the outside of the frame portion when viewed from the third direction.

[0015] According to the energy storage device described in (4) above, a frame portion connecting the first fixed portion and the second fixed portion is arranged so as to be aligned with the terminal block. As a result, the space in which the terminal block is housed becomes more robust. Therefore, according to the energy storage device described in (4) above, the protective performance of the terminal block can be further improved.

[0016] The following description of an energy storage device according to an embodiment (including its modifications) of the present invention will be given with reference to the drawings. The embodiments described below are all general or specific examples. The numerical values, shapes, materials, components, arrangement and connection configurations of components, manufacturing processes, and the order of manufacturing processes shown in the following embodiments are examples and are not intended to limit the present invention. Dimensions and other specifications are not strictly illustrated in each figure. In each figure, the same or similar components are denoted by the same reference numerals.

[0017] In the following description and drawings, the direction along the long side of the rectangular shape of the flattened energy storage element when viewed from the thickness direction (longitudinal direction) is defined as the X-axis direction (first direction). The X-axis direction may also be referred to as the left-right direction. The thickness direction of the energy storage element and the stacking direction of the multiple energy storage elements in the energy storage unit are defined as the Y-axis direction (third direction). The Y-axis direction may also be referred to as the front-back direction. The direction along the short side of the rectangular shape of the energy storage element (short side direction) is defined as the Z-axis direction (second direction). The Z-axis direction may also be referred to as the up-down direction. These X-axis, Y-axis, and Z-axis directions are mutually orthogonal directions. Depending on the usage, the Z-axis direction may not be the up-down direction, but for the sake of explanation below, the Z-axis direction will be described as the up-down direction.

[0018] In the following descriptions and diagrams, the arrow on the X-axis indicates leftward, and the opposite direction indicates rightward. The term "X-axis direction" simply refers to both left and right. The arrow on the Y-axis indicates forward, and the opposite direction indicates backward. The term "Y-axis direction" simply refers to both forward and backward. The arrow on the Z-axis indicates upward, and the opposite direction indicates downward. The term "Z-axis direction" simply refers to both up and down.

[0019] Expressions indicating relative directions or orientations, such as parallel and orthogonal, include cases where the directions or orientations are not strictly accurate. For example, two directions being parallel does not only mean that the two directions are perfectly parallel, but also that they are substantially parallel, i.e., they may have a difference of a few percent. In the following explanation, "insulation" refers to "electrical insulation."

[0020] <Energy Storage Device 1> First, the configuration of the energy storage device 1 in this embodiment will be described. Figure 1 is an exploded perspective view showing the schematic configuration of the energy storage device 1 according to this embodiment. Figure 2 is a perspective view of the energy storage unit 10 of the energy storage device 1. Figure 3 is a front view of the energy storage unit 10, Figure 4 is a top view of the energy storage unit 10, Figure 5 is a bottom view of the energy storage unit 10, Figure 6 is a left side view of the energy storage unit 10, Figure 7 is a right side view of the energy storage unit 10, and Figure 8 is a rear view of the energy storage unit 10.

[0021] The energy storage device 1 is a device that can charge electricity from an external source and discharge electricity to an external source. The energy storage device 1 is used for power storage or power supply purposes. The energy storage device 1 is used as a battery for driving or starting the engine of mobile vehicles such as automobiles, motorcycles, watercraft, ships, snowmobiles, agricultural machinery, construction machinery, or railway vehicles for electric railways.

[0022] Examples of the above-mentioned vehicles include electric vehicles (EVs), hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), and fossil fuel (gasoline, diesel, liquefied natural gas, etc.) vehicles. Examples of the above-mentioned railway vehicles for electric railways include electric trains, monorails, maglev trains, and hybrid trains equipped with both diesel engines and electric motors. The energy storage device 1 can also be used as a stationary battery for household or commercial use, etc.

[0023] The energy storage device 1 comprises an energy storage unit 10 and a unit case 12 that houses the energy storage unit 10. The energy storage device 1 is equipped with external terminals 201 (positive external terminal and negative external terminal) for electrical connection to external devices. The energy storage device 1 may also be equipped with a circuit board and electrical equipment such as relays for monitoring or controlling the charging and discharging states of the energy storage unit 10.

[0024] The energy storage unit 10 is a battery module (battery pack) having a plurality of energy storage elements 100. The energy storage unit 10 has a roughly rectangular parallelepiped shape that is long in the Y-axis direction by stacking the plurality of energy storage elements 100 in the Y-axis direction (front-to-back direction). The energy storage unit 10 is equipped with busbars 300, etc., that connect the plurality of energy storage elements 100 in series or in parallel. The busbars 300, etc., may connect all of the energy storage elements 100 in series, or any of the energy storage elements 100 may be connected in parallel and then connected in series, or all of the energy storage elements 100 may be connected in parallel.

[0025] In this embodiment, as shown in Figure 1, multiple busbars 300 are provided to connect adjacent energy storage elements 100 in the Y-axis direction. The multiple energy storage elements 100 are connected in series using the busbars 300 and connected to the external terminals 201. In this embodiment, the external terminals 201 are located on the front and rear sides of the module body 110, which will be described later. The positive terminal 106 of the energy storage element 100 is electrically connected to one of the external terminals 201 via the busbar 300. The negative terminal 106 of the energy storage element 100 is electrically connected to the other external terminal 201 via the busbar 300.

[0026] The energy storage element 100 is a secondary battery (single cell) that can charge and discharge electricity, and more specifically, a non-aqueous electrolyte secondary battery such as a lithium-ion secondary battery. The energy storage element 100 has a flattened rectangular parallelepiped shape (square, prism) in the Y-axis direction. In this embodiment, multiple energy storage elements 100 are arranged in line in the Y-axis direction, but the number of energy storage elements 100 is not particularly limited.

[0027] The energy storage element 100 is not limited to a non-aqueous electrolyte secondary battery, but may be a secondary battery other than a non-aqueous electrolyte secondary battery, or a capacitor. The energy storage element 100 may not be a secondary battery, but a primary battery that allows the user to use the stored electricity without charging. The energy storage element 100 may be a battery using a solid electrolyte. The energy storage element 100 may be a pouch-type battery.

[0028] The unit case 12, which houses the energy storage unit 10, is a roughly rectangular parallelepiped (box-shaped) container that constitutes the outer casing (shell) of the energy storage device 1. The unit case 12 is positioned outside the energy storage unit 10, fixing the energy storage unit 10 in a predetermined position and protecting it from impacts and the like.

[0029] The unit case 12 is a metal case formed from a metal component such as aluminum, aluminum alloy, stainless steel, iron, or plated steel sheet. For example, the unit case 12 is formed from aluminum die casting. The unit case 12 may also be formed from a high-strength resin material (insulating material).

[0030] <Energy Storage Unit 10> As shown in Figures 1 to 8, the energy storage element 100 has a flattened shape with its thickness direction oriented in the front-to-back direction. When viewed from the thickness direction, the energy storage element 100 has a rectangular shape that is long in the left-to-right direction. The energy storage element 100 constitutes a rectangular corner cell when viewed from the thickness direction. The positive and negative terminals 106 are distributed and arranged on the left and right sides (short sides 102) of the energy storage element 100. A gas discharge valve 107 is arranged on at least one of the left and right sides. The explanation of the internal structure of the energy storage element 100 is omitted.

[0031] Each energy storage element 100 has a long side portion 101 along the long side of the rectangle and a short side portion 102 along the short side of the rectangle. Hereinafter, the virtual surface that includes the upper long side portion 101 of each energy storage element 100 and faces upward will be referred to as the upper surface 101a of the energy storage element 100. The virtual surface that includes the lower long side portion 101 of each energy storage element 100 and faces downward will be referred to as the lower surface 101b of the energy storage element 100. The upper surface 101a and the lower surface 101b are planes perpendicular to the Z-axis direction.

[0032] Furthermore, the imaginary surface facing left, including the left short side portion 102 of each energy storage element 100, is defined as the left side surface 102a (first surface) of the energy storage element 100. The imaginary surface facing right, including the right short side portion 102 of each energy storage element 100, is defined as the right side surface 102b (first surface) of the energy storage element 100. The left side surface 102a and the right side surface 102b are surfaces perpendicular to the X-axis direction.

[0033] The energy storage element 100 is arranged with its longitudinal direction (long side) aligned with the longer side 101 of the rectangular shape (longitudinal direction) in the left-right direction (X-axis direction), its short side 102 aligned with the shorter side (short side direction) in the up-down direction (Z-axis direction), and its thickness direction aligned with the front-back direction (Y-axis direction).

[0034] A module body 110 (module) is formed by stacking multiple energy storage elements 100 so that they overlap in the thickness direction (Y-axis direction). Hereinafter, the Y-axis direction may be referred to as the stacking direction of the module body 110. A pair of end plates 115 (end members) are arranged on the outermost surfaces 111 on both sides of the stacking direction of the module body 110.

[0035] For example, the end plate 115 is not limited to an actual plate material, but may be a virtual plate material formed by arranging a framework of multiple beams in a plate shape. For example, each end plate 115 may be a rectangular plate shape that overlaps with the energy storage element 100 when viewed from the stacking direction. In this embodiment, the end plate 115 comprises a plate-shaped plate portion 130 and a framework-shaped frame portion 140. These plate portion 130 and frame portion 140 are stacked in the Y-axis direction such that the frame portion 140 is located on the outside (opposite side from the module body 110) and the plate portion 130 is located on the inside.

[0036] The end plate 115 has a flattened shape with its thickness direction oriented in the front-to-back direction. When viewed from the thickness direction, the end plate 115 has a rectangular shape that is long in the left-to-right direction. The end plate 115 has a long side portion 116 along the long side of the rectangle and a short side portion 117 along the short side of the rectangle. Hereinafter, the imaginary surface that includes the upper long side portion 116 of each end plate 115 and faces upward will be referred to as the upper surface 116a of the end plate 115. The imaginary surface that includes the lower long side portion 116 of each end plate 115 and faces downward will be referred to as the lower surface 116b of the end plate 115.

[0037] Furthermore, the imaginary surface facing left, including the left short side portion 117 of each end plate 115, is defined as the left side surface 117a of the end plate 115. The imaginary surface facing right, including the right short side portion 117 of each end plate 115, is defined as the right side surface 117b of the end plate 115.

[0038] A bind bar 120 extends between the central parts of the rectangular long sides 116 of the end plates 115 on both sides in the stacking direction. Both ends 121 of the bind bar 120 in the longitudinal direction (stacking direction) are fastened to the central parts of the long sides 116 of the end plates 115 on both sides in the stacking direction.

[0039] The virtual surface extending between the upper surfaces 116a of the end plates 115 on both sides in the stacking direction is defined as the upper surface 112a of the module body 110, and the virtual surface extending between the lower surfaces 116b of the end plates 115 on both sides in the stacking direction is defined as the lower surface 112b of the module body 110.

[0040] Multiple upper surfaces 101a of energy storage elements 100 are arranged on the upper surface 112a of the module body 110. Multiple lower surfaces 101b of energy storage elements 100 are arranged on the lower surface 112b of the module body 110. The direction along the long side portion 101 of each energy storage element 100 and the long side portion 116 of each end plate 115 is defined as the longitudinal direction of the energy storage elements 100 and end plates 115 (and consequently the module body 110).

[0041] Of the directions along the upper surface 112a and lower surface 112b of the module body 110, the stacking direction is defined as the front-to-back direction (Y-axis direction), and the direction intersecting (orthogonal to) the stacking direction is defined as the left-to-right direction (X-axis direction). The direction intersecting (orthogonal to) the upper surface 112a and lower surface 112b is defined as the up-and-down direction (Z-axis direction).

[0042] The virtual surface extending between the left side surfaces 117a of the end plates 115 on both sides in the stacking direction is defined as the left side surface 113a of the module body 110, and the virtual surface extending between the right side surfaces 117b of the end plates 115 on both sides in the stacking direction is defined as the right side surface 113b of the module body 110.

[0043] On the left side surface 113a of the module main body 110, the left side surfaces 102a of the plurality of electricity storage elements are aligned. On the right side surface 113b of the module main body 110, the right side surfaces 102b of the plurality of electricity storage elements are aligned. The direction along the short side portion 102 of each electricity storage element 100 and the short side portion 117 of each end plate 115 is defined as the widthwise direction of the electricity storage elements 100 and the end plates 115 (and consequently the module main body 110).

[0044] The above arrangement of the module main body 110 is an example, and for example, an arrangement in which the longitudinal direction of the module main body 110 is not horizontal but inclined or vertical may be adopted.

[0045] <Bind Bars 120> As shown in FIGS. 1 to 8, between the upper long side portions 116 and between the lower long side portions 116 of the end plates 115 on both sides in the stacking direction are respectively connected by bind bars 120 extending in the stacking direction. Each bind bar 120 is provided along the upper surface 112a or the lower surface 112b of the module main body 110. Each bind bar 120 is formed in a plate shape (band shape) along the upper surface 112a or the lower surface 112b of the module main body 110.

[0046] Each bind bar 120 extends in the stacking direction, and end portions 121 on both sides in the length direction are respectively fastened to the end plates 115 on both sides in the stacking direction. The end portions 121 on both sides of each bind bar 120 are fixed to the corresponding end plate 115, for example, by fastening using a bolt B1 along the stacking direction. Note that the end plate 115 and the bind bar 120 may be fastened by being joined via welding, an adhesive, or the like.

[0047] The upper and lower binding bars 120 are provided, for example, vertically symmetrically. Each binding bar 120 is formed symmetrically, for example, in the length direction (stacking direction). Each of the front and rear end portions 121 of the upper binding bar 120 includes a first piece 121a along the upper surface 112a of the module body 110, and a second piece 121b along the outermost surface 111 of the end plate 115. Each of the end portions 121 of the lower binding bar 120 includes a first piece 121a along the lower surface 112b of the module body 110, and a second piece 121b along the outermost surface 111 of the end plate 115. The front and rear end portions 121 of each binding bar 120 are each bent into an L-shape when viewed from the left-right direction and are integrally formed.

[0048] <Side Plate 125> The electricity storage unit 10 includes a pair of left and right side plates 125 (side members) and a pair of front and rear end plates 115. The front and rear end plates 115 and the left and right side plates 125 are connected into a frame shape surrounding the outer periphery of the module body 110 in a plan view. The plurality of electricity storage elements 100 in the module body 110 are constrained in a stacked state by the front and rear end plates 115 and the left and right side plates 125. The central portion in the longitudinal direction of the module body 110 is constrained in a stacked state by the upper and lower binding bars 120.

[0049] The module body 110 is integrated by the front and rear end plates 115, the left and right side plates 125, and further the upper and lower binding bars 120, so that the electricity storage unit 10 can be easily handled as an integrated unit. The front and rear end plates 115 and the left and right side plates 125 serve as an outer frame, so that the electricity storage unit 10 is robust against inputs from inside and outside.

[0050] The side plates 125 are provided on the left and right sides of the module body 110. The left side plate 125 and the right side plate 125 are formed in a symmetrical shape. Each side plate 125 includes a side wall portion 125a, an upper flange portion 125b, an upper corner portion 125c (bent portion), a lower flange portion 125d, a lower corner portion 125e, a first fixing portion 125f, a connecting portion 125g, a second fixing portion 125h, and a third fixing portion 125i.

[0051] The side wall portion 125a is a wall portion positioned opposite to the side of the energy storage element 100 perpendicular to the X-axis direction. The side wall portion 125a of the side plate 125 located on the left side of the module body 110 is positioned opposite to the left side surface 102a of the energy storage element 100. The side wall portion 125a of the side plate 125 located on the right side of the module body 110 is positioned opposite to the right side surface 102b of the energy storage element 100. The side wall portion 125a presses the energy storage element 100 from the outside in the X-axis direction.

[0052] The side wall portion 125a extends along the Y-axis direction, and its end portion 125j in the Y-axis direction is located further outward in the Y-axis direction than the external terminal 201. In other words, the front end portion 125j of the side wall portion 125a is located in front of the external terminal 201, which is located at the front. Also, the rear end portion 125j of the side wall portion 125a is located behind the external terminal 201, which is located at the rear.

[0053] The upper flange piece 125b is the part that faces the upper surface 101a of the energy storage element 100. The upper flange piece 125b is connected to the upper end of the side wall 125a via the upper corner portion 125c. The upper flange piece 125b of the side plate 125 located on the left side of the module body 110 is formed to protrude to the right from the upper corner portion 125c when viewed from the Y-axis direction. The upper flange piece 125b of the side plate 125 located on the right side of the module body 110 is formed to protrude to the left from the upper corner portion 125c when viewed from the Y-axis direction. The upper flange piece 125b holds the energy storage element 100 in place from above.

[0054] The upper corner portion 125c is a bent portion that connects the side wall portion 125a and the upper flange piece 125b.

[0055] The lower flange piece 125d is the portion facing the lower surface 101b of the energy storage element 100. The lower flange piece 125d is connected to the lower end of the side wall portion 125a via the lower corner portion 125e. The lower flange piece 125d of the side plate 125 located on the left side of the module body 110 is formed to protrude to the right from the lower corner portion 125e when viewed from the Y-axis direction. The lower flange piece 125d of the side plate 125 located on the right side of the module body 110 is formed to protrude to the left from the lower corner portion 125e when viewed from the Y-axis direction. The lower flange piece 125d holds the energy storage element 100 in place from below.

[0056] The lower corner portion 125e is a bent portion that connects the side wall portion 125a and the lower flange piece 125d.

[0057] The first fixing portion 125f, the second fixing portion 125h, and the third fixing portion 125i are parts that are fixed to the end plate 115. The first fixing portion 125f, the second fixing portion 125h, and the third fixing portion 125i can be fixed to the end plate 115 by bolts (not shown).

[0058] The first fixing portion 125f is a fixing portion connected to the upper flange piece 125b via a connecting portion 125g. The first fixing portion 125f is provided at each end of the side plate 125 in the Y-axis direction. The first fixing portion 125f located on the front side is fixed to the front end plate 115. The first fixing portion 125f located on the rear side is fixed to the rear end plate 115.

[0059] The first fixing portion 125f is located on the central side of the energy storage element 100 in the X-axis direction, beyond the end of the upper flange piece 125b on the central side of the energy storage element 100. The first fixing portion 125f provided on the side plate 125 located on the left side of the module body 110 is located to the right of the left end of the upper flange piece 125b. The first fixing portion 125f provided on the side plate 125 located on the right side of the module body 110 is located to the left of the right end of the upper flange piece 125b.

[0060] The connecting portion 125g is the part that connects the first fixing portion 125f and the upper flange piece 125b. The connecting portion 125g extends outward in the X-axis direction as it moves from the first fixing portion 125f toward the center of the module body 110 in the Y-axis direction.

[0061] The second fixing portion 125h is provided at the Y-axis end of the lower flange piece 125d and is fixed to the end plate 115 from below. In the X-axis direction, the second fixing portion 125h is located further out from the energy storage element 100 than the first fixing portion 125f. The second fixing portion 125h provided on the side plate 125 located on the left side of the module body 110 is located to the left of the first fixing portion 125f provided on the same side plate 125. The second fixing portion 125h provided on the side plate 125 located on the right side of the module body 110 is located to the right of the first fixing portion 125f provided on the same side plate 125. This allows the second fixing portion 125h to be directly attached to the lower flange piece 125d, and allows a wider area of ​​the lower surface 112b of the module body 110 to be exposed than when a connecting portion is provided to connect the second fixing portion 125h and the lower flange piece 125d. Therefore, the cooling efficiency of the module body 110 can be improved.

[0062] The third fixing portion 125i is provided at the lower parts of both ends of the side wall portion 125a in the Y-axis direction and is fixed to the end plate 115 from the X-axis direction. The third fixing portion 125i provided on the side plate 125 located on the left side of the module body 110 is fixed to the end plate 115 from the left side. The third fixing portion 125i provided on the side plate 125 located on the right side of the module body 110 is fixed to the end plate 115 from the right side.

[0063] <End Plate 115> Each end plate 115 comprises a plate-shaped plate portion 130 and a frame-shaped frame portion 140, as described above. The plate portion 130 is located closer to the module body 110 than the frame portion 140. In the case of an end plate 115 located in front of the module body 110, the plate portion 130 is located behind the frame portion 140. In the case of an end plate 115 located behind the module body 110, the plate portion 130 is located in front of the frame portion 140.

[0064] The plate portion 130 is a plate-shaped part positioned opposite the end face of the module body 110 that is perpendicular to the Y-axis direction. The plate portion 130 is formed to cover the end face of the module body 110 that is perpendicular to the Y-axis direction when viewed from the Y-axis direction.

[0065] The frame portion 140 includes a bind bar fixing portion 141, a first fixing portion 142, a second fixing portion 143, a third fixing portion 144, a mounting portion 145, and a plurality of arm portions 146. The frame portion 140 is formed in a flat shape as a whole, with the bind bar fixing portion 141, the first fixing portion 142, the second fixing portion 143, the third fixing portion 144, the mounting portion 145, and the plurality of arm portions 146 being integrally connected.

[0066] The bind bar fixing section 141 is located in the center of the frame section 140 in the X-axis direction. The bind bar fixing section 141 is the part to which the bind bar 120 is fixed. The bind bar 120 located on the upper side of the module body 110 is fixed to the upper part of the bind bar fixing section 141 using bolts B1. The bind bar 120 located on the lower side of the module body 110 is fixed to the lower part of the bind bar fixing section 141 using bolts B1.

[0067] The first fixing portion 142 is a part that is fixed to the first fixing portion 125f of the side plate 125, and two are provided for each frame portion 140, sandwiching the bind bar fixing portion 141 in the X-axis direction. Each first fixing portion 142 is located below the first fixing portion 125f of the side plate 125. The first fixing portion 142 located to the left of the bind bar fixing portion 141 is fixed to the first fixing portion 125f of the side plate 125 located to the left of the module body 110. The first fixing portion 142 located to the right of the bind bar fixing portion 141 is fixed to the first fixing portion 125f of the side plate 125 located to the right of the module body 110.

[0068] The second fixing portion 143 is a part that is fixed to the second fixing portion 125h of the side plate 125, and two are provided for each frame portion 140, sandwiching the bind bar fixing portion 141 in the X-axis direction. Each second fixing portion 143 is located above the second fixing portion 125h of the side plate 125. The second fixing portion 143 located to the left of the bind bar fixing portion 141 is fixed to the second fixing portion 125h of the side plate 125 located to the left of the module body 110. The second fixing portion 143 located to the right of the bind bar fixing portion 141 is fixed to the second fixing portion 125h of the side plate 125 located to the right of the module body 110.

[0069] The third fixing portion 144 is a part that is fixed to the third fixing portion 125i of the side plate 125, and two are provided for each frame portion 140, sandwiching the bind bar fixing portion 141 in the X-axis direction. Each third fixing portion 144 is located to the side of the third fixing portion 125i of the side plate 125. The third fixing portion 144 located to the left of the bind bar fixing portion 141 is fixed to the third fixing portion 125i of the side plate 125 located to the left of the module body 110. The third fixing portion 144 located to the right of the bind bar fixing portion 141 is fixed to the third fixing portion 125i of the side plate 125 located to the right of the module body 110.

[0070] The mounting portion 145 is a part for fixing the end plate 115 to an external member (for example, the unit case 12). Two mounting portions 145 are provided for each frame portion 140, sandwiching the bind bar fixing portion 141 in the X-axis direction. The mounting portions 145 are located below the first fixing portion 142 and above the second fixing portion 143, and are located further outside the energy storage element 100 than the first fixing portion 142 in the X-axis direction. The mounting portion 145 located to the left of the bind bar fixing portion 141 is located to the left of the first fixing portion 142, which is located to the left of the bind bar fixing portion 141. The mounting portion 145 located to the right of the bind bar fixing portion 141 is located to the left of the first fixing portion 142, which is located to the right of the bind bar fixing portion 141.

[0071] The multiple arm portions 146 are parts that connect two of the bind bar fixing portion 141, the first fixing portion 142, the second fixing portion 143, the third fixing portion 144, and the mounting portion 145. In this embodiment, the arm portions 146 include an arm portion 146 that connects the left first fixing portion 142 and the left mounting portion 145, an arm portion 146 that connects the upper part of the bind bar fixing portion 141 and the left mounting portion 145, and an arm portion 146 that connects the lower part of the bind bar fixing portion 141 and the left mounting portion 145. In addition, the arm portions 146 include an arm portion 146 that connects the right first fixing portion 142 and the right mounting portion 145, an arm portion 146 that connects the upper part of the bind bar fixing portion 141 and the right mounting portion 145, and an arm portion 146 that connects the lower part of the bind bar fixing portion 141 and the right mounting portion 145.

[0072] In this type of end plate 115, the first fixing portion 142 is located closer to the center of the energy storage element 100 in the X-axis direction than the second fixing portion 143 and the mounting portion 145. In other words, the first fixing portion 142, located to the left of the bind bar fixing portion 141, is located to the right in the X-axis direction than the second fixing portion 143 and the mounting portion 145, which are also located to the left of the bind bar fixing portion 141.

[0073] Furthermore, the arm portion 146 connecting the first fixing portion 142 and the mounting portion 145 is inclined so as it extends downwards, it moves outwards in the X-axis direction. In other words, on the left side of the bind bar fixing portion 141, the arm portion 146 connecting the first fixing portion 142 and the mounting portion 145 is inclined so as it extends downwards, it moves to the left. This arm portion 146 connecting the first fixing portion 142 and the mounting portion 145 forms part of the outer edge of the frame portion 140.

[0074] The first fixing portion 142, the second fixing portion 143, the mounting portion 145, and the arm portion 146 are located outward in the Y-axis direction from the plate portion 130. For this reason, the end plate 115 is provided with a recess 147 surrounded by the first fixing portion 142, the mounting portion 145, the arm portion 146, and the plate portion 130.

[0075] The recess 147 is formed to be recessed below the upper surface 116a (second surface) of the end plate 115. The recess 147 is also formed to be recessed from the left side surface 117a (or right side surface 117b) toward the center in the X-axis direction (bind bar fixing part 141). Furthermore, the recess 147 is recessed toward the center of the module body 110 toward the end 125j of the side plate 125 in the Y-axis direction. Such a recess 147 is a recess recessed relative to the upper surface 116a and left side surface 117a of the end plate 115.

[0076] <External Terminal 201> The external terminal 201 is provided on the terminal block 200. Each end plate 115 is provided with a recess 147 as described above. The terminal block 200 is housed in the recess 147 of the end plate 115. The terminal block 200 comprises the external terminal 201 and a base portion 202. The external terminal 201 is a total terminal connected to the terminals 106 of the multiple energy storage elements 100 via the bus bar 300. The base portion 202 supports the external terminal 201.

[0077] The external terminals 201 are located on the front and rear sides of the module body 110. One of these external terminals 201 is a positive external terminal electrically connected to the positive terminal 106 of the energy storage element 100. The other external terminal 201 is a negative external terminal electrically connected to the negative terminal 106 of the energy storage element 100.

[0078] In this embodiment, the terminal block 200 is positioned such that, for example, as shown in Figure 3 or Figure 8, the entire terminal block 200 is positioned in the direction toward the inside of the module body 110 in the X-axis direction relative to the side wall portion 125a of the side plate 125. The terminal block 200 is also positioned such that the entire terminal block 200 is positioned in the direction toward the inside of the module body 110 in the Z-axis direction relative to the upper flange piece 125b of the side plate 125. Furthermore, at least the external terminals 201 of the terminal block 200 are positioned such that the entire terminal block 200 is positioned in the direction toward the inside of the module body 110 in the Y-axis direction relative to the end portion 125j of the side plate 125. As a result, external forces acting from the outside in the X-axis direction, the Y-axis direction, and the Z-axis direction can be prevented from acting on the terminal block 200.

[0079] The energy storage device 1 of this embodiment, as described above, comprises a module body 110, an end plate 115, and a terminal block 200. The module body 110 has multiple energy storage elements 100 stacked in the Y-axis direction, which is perpendicular to the X-axis direction and the Z-axis direction. The energy storage elements 100 are rectangular parallelepipeds in which the dimension in the X-axis direction is larger than the dimension in the Z-axis direction, which is perpendicular to the X-axis direction. The end plate 115 is positioned opposite the end face of the module body 110 in the Y-axis direction. The terminal block 200 is electrically connected to the terminals 106 of the multiple energy storage elements 100. The end plate 115 is also provided with a recess 147. The recess 147 is recessed inward in the Z-axis direction from the end face in the Z-axis direction when viewed from the Y-axis direction, and is recessed inward in the Y-axis direction from the end face of the end plate 115 in the Y-axis direction. At least a part of the terminal block 200 is housed in the recess 147.

[0080] In this embodiment of the energy storage device 1, a recess 147 is provided in the end plate 115. Furthermore, at least a portion of the terminal block 200, which is electrically connected to the terminals 106 of the multiple energy storage elements 100, is housed in the recess 147. Therefore, when an external force is applied to the energy storage device 1 from the outside, the external force acting on the terminal block 200 can be suppressed. Accordingly, the energy storage device 1 of this embodiment can improve the protective performance of the terminal block 200 connected to the terminals of the multiple energy storage elements 100.

[0081] In the energy storage device 1 of this embodiment, it is preferable that the terminal block 200 is located closer to the center of the module body 110 in the Y-axis direction than the outermost part of the end plate 115 in the Y-axis direction.

[0082] If the outermost part of the end plate 115 in the Y-axis direction is the edge of the first fixing portion 142 of the frame portion 140, it is preferable that the terminal block 200 be positioned closer to the center of the module body 110 in the Y-axis direction than the edge of the first fixing portion 142. This prevents external forces input from the outside in the Y-axis direction from being transmitted to the end plate 115 and then to the terminal block 200. Therefore, the protective performance of the terminal block 200 can be further improved.

[0083] The energy storage device 1 of this embodiment includes a side plate 125 positioned opposite the left side surface 102a of the energy storage element 100, which is perpendicular to the X-axis direction. The side plate 125 has a fixing portion that is fixed to the end plate 115. One of the fixing portions, the first fixing portion 125f, is located in the X-axis direction on the central side of the energy storage element 100, relative to the left side surface 102a of the energy storage element 100. The terminal block 200 is located in the X-axis direction between the first fixing portion 125f and the end of the end plate 115 in the X-axis direction (for example, the outer edge of the plate portion 130 in the X-axis direction).

[0084] According to the energy storage device 1 of this embodiment, external forces input from the outside in the X-axis direction can be suppressed from being transmitted to the end plate 115 and then to the terminal block 200. Therefore, according to the energy storage device 1 of this embodiment, the protective performance of the terminal block 200 can be further improved.

[0085] In the energy storage device 1 of this embodiment, the first fixing portion 125f is located on one end side of the end plate 115 in the Z-axis direction when viewed from the Y-axis direction. The side plate 125 is located on the other end side of the end plate 115 in the Z-axis direction when viewed from the Y-axis direction. Furthermore, the side plate 125 has a second fixing portion 125h which is a fixing portion located at the end of the end plate 115 in the X-axis direction. The end plate 115 has a frame portion 140 that connects the first fixing portion 125f and the second fixing portion 125h. The terminal block 200 is located on the inside of the outer edge of the end plate 115 and outside of the frame portion 140 when viewed from the Y-axis direction.

[0086] In this embodiment of the energy storage device 1, a frame portion 140 connecting the first fixing portion 125f and the second fixing portion 125h is arranged so as to be aligned with the terminal block 200. Specifically, an arm portion 146 forming a part of the outer edge of the frame portion 140 is arranged so as to be aligned with the terminal block 200. As a result, the space in which the terminal block 200 is housed becomes more robust. Therefore, the energy storage device 1 of this embodiment can further improve the protective performance of the terminal block 200.

[0087] The present invention is not limited to the embodiments described above, and includes various modifications to the embodiments described above, without departing from the spirit of the invention. Forms constructed by arbitrarily combining the components of the above embodiments and their modifications are also included within the scope of the present invention.

[0088] For example, the above embodiment described a configuration comprising two side plates 125. However, the present invention is not limited thereto, and for example, a configuration comprising one side plate 125, with the other being supported by a module case or the like, can also be adopted.

[0089] Furthermore, a portion of the terminal block 200 may protrude from the recess 147. In other words, the present invention is not limited to a configuration in which the entire terminal block 200 is housed in the recess 147.

[0090] Furthermore, similar to the first fixing portion 142, the second fixing portion 143 and the mounting portion 145 may be positioned towards the central part of the energy storage element 100 in the X-axis direction. By adopting such a configuration, it is possible to increase the spatial capacity of the recess 147.

[0091] This invention can be applied to energy storage devices that stack multiple energy storage elements, such as lithium-ion secondary batteries.

[0092] 1...Energy storage device 100...Energy storage element 101...Long side 101a...Top surface 101b...Bottom surface 102...Short side 102a...Left side 102b...Right side 106...Terminal 107...Gas discharge valve 110...Module body (module) 111...Outermost surface 112a...Top surface 112b...Bottom surface 113a...Left side (first surface) 113b...Right side (first surface) 115...End plate (end member) 116...Long side 116a...Top surface 116b...Bottom surface 117...Short side 117a...Left side 117b...Right side 120...Bind bar 125...Side plate (side member) 125a...Side wall 125b...Upper flange piece 125c...Upper corner 125d...Lower flange piece 125e...Lower corner section 125f...First fixing section 125g...Connection section 125h...Second fixing section 125i...Third fixing section 125j...End section 130...Plate section 140...Frame section 141...Bind bar fixing section 142...First fixing section 143...Second fixing section 144...Third fixing section 145...Mounting section 146...Arm section 147...Recess 200...Terminal block 201...External terminal 202...Base section 300...Bus bar

Claims

1. A power storage device comprising: a module in which a plurality of rectangular parallelepiped energy storage elements, the dimensions in a first direction being larger than the dimensions in a second direction perpendicular to the first direction, are stacked in a third direction perpendicular to the first and second directions; an end member positioned opposite the end face of the module in the third direction; and a terminal block electrically connected to the terminals of the plurality of energy storage elements, wherein the end member is provided with a recess, the recess is recessed inward in the second direction from the end face in the second direction as viewed from the third direction, and recessed inward in the third direction from the end face of the end member in the third direction; and at least a portion of the terminal block is housed in the recess.

2. The energy storage device according to claim 1, wherein the terminal block is located on the central side of the module in the third direction, rather than on the outermost part of the end member in the third direction.

3. The energy storage device according to claim 1 or 2, comprising a side member disposed opposite to the first surface of the energy storage element perpendicular to the first direction, wherein the side member has at least one fixing portion fixed to the end member, the first fixing portion being one of the fixing portions located on the central side of the energy storage element in the first direction relative to the first surface of the energy storage element, and the terminal block being located between the first fixing portion and the end of the end member in the first direction.

4. The energy storage device according to claim 3, wherein the first fixing portion is located on one end side of the end member in the second direction when viewed from the third direction, the side member has a second fixing portion which is the fixing portion located on the other end side of the end member in the second direction and at the end of the end member in the first direction when viewed from the third direction, the end member includes a frame portion connecting the first fixing portion and the second fixing portion, and the terminal block is located on the inside of the outer edge of the end member and on the outside of the frame portion when viewed from the third direction.

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