Power storage device

Abstract

To provide a power storage device having improved reliability with a simple structure.SOLUTION: A power storage device comprises: a plurality of power storage elements 100 aligned in a first direction Y; and a plurality of holders 200, aligned in the first direction, each of which holds one or more of the plurality of power storage elements. The plurality of holders include: a first holder 200A; and a second holder 200B which is disposed on one side in the first direction of the first holder. Each of the plurality of power storage elements has a terminal in a second direction Z. The first holder has: a first holder body 201A; a first protruding part 210A protruding from the first holder body; and a first projecting portion 211A provided on the first protruding part. The first protruding part is disposed at an end in a third direction X of the first holder body. The first projecting portion protrudes from the first protruding part to one side in the first direction. The second holder has: a second holder body; a second protruding part 210B protruding from the second holder body; and a second opening part 211B penetrating the second protruding part in the first direction. The first projecting portion is inserted in the second opening part and penetrates the second opening part.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to an electricity storage device. [Background technology]

[0002] Patent Document 1 discloses a battery module having multiple battery cells. Each battery cell is held in a separate battery holder and arranged side by side. The battery cells held in each battery holder are sandwiched between a first end plate and a second end plate provided on both sides in the juxtaposition direction. A bolt is inserted through the first end plate toward the second end plate, and a nut is screwed onto the bolt inserted through the second end plate, so that the battery cells held in each battery holder are sandwiched between the first end plate and the second end plate. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-54063 Summary of the Invention [Problem to be solved by the invention]

[0004] In the conventional battery module described above, multiple battery cells arranged side by side and held in individual battery holders are sandwiched between a first end plate and a second end plate connected by bolts and nuts. While this structure allows the array of multiple battery holders and multiple battery cells to be fixed in the juxtaposition direction of the battery cells, multiple sets of elongated bolts and nuts are used in the juxtaposition direction. This can result in problems such as an increase in the weight of the battery module and / or an increase in the number of parts in the battery module.

[0005] The present invention was made by the inventors of the present application by focusing on the above-mentioned problem, and has an object to provide a power storage device with a simple configuration and improved reliability. [Means for solving the problem]

[0006] An energy storage device according to one aspect of the present invention includes a plurality of energy storage elements arranged in a first direction, and a plurality of holders arranged in the first direction, each holder holding one or more of the energy storage elements, the plurality of holders including a first holder and a second holder disposed on one side of the first holder in the first direction, each of the plurality of energy storage elements having a terminal in a second direction perpendicular to the first direction, the first holder including a first holder main body and a first holder protruding from the first holder main body, The second holder comprises a protruding portion and a first convex portion provided on the first protruding portion, the first protruding portion being arranged at an end of the first holder body in a third direction perpendicular to the first direction and the second direction, and the first convex portion protruding from the first protruding portion to one side in the first direction, the second holder comprising a second holder body, a second protruding portion protruding from the second holder body, and a second opening penetrating the second protruding portion in the first direction, and the first convex portion being inserted into the second opening and penetrating the second opening. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a power storage device with a simple configuration and improved reliability. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view showing the configuration of an electricity storage device according to an embodiment. [Figure 2] FIG. 2 is an exploded perspective view of the electricity storage unit according to the embodiment. [Figure 3] FIG. 3 is a perspective view showing the configuration of the holder and its surroundings according to the embodiment. [Figure 4] FIG. 4 is a first partial perspective view showing a part of the electricity storage unit according to the embodiment. [Figure 5] FIG. 5 is a second partial perspective view showing a part of the electricity storage unit according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] (1) An energy storage device according to one aspect of the present invention includes a plurality of energy storage elements arranged in a first direction, and a plurality of holders arranged in the first direction, each holder holding one or more of the energy storage elements, the plurality of holders including a first holder and a second holder disposed on one side of the first holder in the first direction, each of the energy storage elements having a terminal in a second direction perpendicular to the first direction, the first holder including a first holder main body and a second holder protruding from the first holder main body. The second holder comprises a first protrusion and a first convex portion provided on the first protrusion, the first protrusion being arranged at an end of the first holder body in a third direction perpendicular to the first direction and the second direction, the first convex portion protruding from the first protrusion to one side in the first direction, the second holder comprising a second holder body, a second protrusion protruding from the second holder body, and a second opening penetrating the second protrusion in the first direction, the first convex portion being inserted into the second opening and penetrating the second opening.

[0010] In an energy storage device according to one aspect of the present invention, the first holder has a first protrusion protruding toward one side in a first direction, which is the arrangement direction of the plurality of energy storage elements, and the second holder has a second opening into which the first protrusion is inserted. In other words, two holders adjacent to each other in the first direction are connected. Therefore, for example, movement of the first holder in the second direction is restricted by the second holder. This allows, for example, the plurality of energy storage elements to be accurately arranged in the first direction without using any other components. Furthermore, the first protrusion is provided on a first protrusion protruding from a first holder main body, and the second opening is provided on a second protrusion protruding from a second holder main body. Therefore, for example, the size and shape of the first protrusion and the second opening are highly flexible. Furthermore, the first protrusion is disposed so as to penetrate the second opening. Therefore, the length of the first protrusion in the first direction can be increased compared to when the second opening is a bottomed hole. This makes it less likely for the first protrusion to come off the second opening. Thus, the energy storage device according to this aspect is a simple configuration with improved reliability.

[0011] (2) In the electricity storage device described above in (1), the first protrusion may protrude in the third direction from an end of the first holder body in the third direction.

[0012] According to the energy storage device described in (2) above, the first protrusion and the second protrusion can be arranged in a manner that does not consume space in the second direction of the structure including the plurality of energy storage elements and the plurality of holders. Therefore, for example, the presence of the first protrusion is unlikely to interfere with the joining operation of the terminal and the conductive member such as the bus bar.

[0013] (3) In the energy storage device described in (1) or (2) above, the first holder may hold a first energy storage element among the plurality of energy storage elements, the first holder main body may have a first side wall portion facing the side surface of the first energy storage element in the third direction, and the first protrusion portion may be provided on the first side wall portion.

[0014] According to the electricity storage device described in (3) above, the first protruding portion is provided to protrude from the first side wall portion of the first holder body, and therefore the first protruding portion is supported more stably.

[0015] (4) In the energy storage device described in any one of (1) to (3) above, the plurality of holders may further include a third holder arranged on the other side of the first holder in the first direction, and the first holder may further be arranged at an end of the first holder body in the third direction and include a third protrusion protruding from the first holder body and a first opening provided in the third protrusion, and the third holder may include a third holder body, a fourth protrusion protruding from the third holder body, and a third convex portion provided in the fourth protrusion, and the third convex portion may be inserted into the first opening.

[0016] According to the energy storage device described in (4) above, the first holder and the second and third holders that sandwich the first holder in the first direction are connected to each other, so that the plurality of energy storage elements can be aligned in the first direction with greater precision.

[0017] (5) In the energy storage device described in (4) above, the first protruding portion and the third protruding portion may be arranged at different positions on the first holder in the second direction.

[0018] According to the energy storage device described in (5) above, the first protrusion and the third protrusion are arranged at different positions in the second direction, so that, for example, the third convex portion inserted into the first opening of the third protrusion is prevented from interfering with the first protrusion.

[0019] Hereinafter, with reference to the drawings, a description will be given of an energy storage device according to an embodiment of the present invention (including its modified examples). The embodiments described below are all comprehensive or specific examples. The numerical values, shapes, materials, components, component placement and connection configurations, manufacturing processes, and the order of manufacturing processes shown in the following embodiments are examples only and are not intended to limit the present invention. In each drawing, dimensions and the like are not strictly illustrated. In each drawing, the same or similar components are designated by the same reference numerals.

[0020] In the following description and drawings, the X-axis direction is defined as the direction in which a pair of terminals of an energy storage element are aligned, or the direction in which a pair of short side surfaces of a container for the energy storage element face each other. The Y-axis direction is defined as the direction in which a pair of long side surfaces of a container for the energy storage element face each other, the thickness direction (flattening direction) of the container for the energy storage element, or the direction in which multiple energy storage elements of the energy storage unit are aligned. The Z-axis direction is defined as the direction in which the terminals of the energy storage element protrude, the direction in which the container body and the cover plate of the energy storage element are aligned, or the up-down direction. The X-axis direction, Y-axis direction, and Z-axis direction intersect each other (orthogonal in this embodiment). Depending on the mode of use, the Z-axis direction may not be the up-down direction, but for convenience of explanation, the following description will be made assuming that the Z-axis direction is the up-down direction.

[0021] In the following description, the positive X-axis direction refers to the direction of the X-axis arrow, and the negative X-axis direction refers to the direction opposite to the positive X-axis direction. When simply referring to the X-axis direction, it refers to both or either of the positive X-axis direction and the negative X-axis direction. When referring to one side and the other side of the X-axis direction, it refers to one and the other of the positive X-axis direction and the negative X-axis direction. The same applies to the Y-axis and Z-axis directions. Expressions indicating relative directions or attitudes, such as parallel and orthogonal, also include cases where the directions or attitudes are not strictly those of the two directions. For example, when two directions are parallel, it does not only mean that the two directions are completely parallel, but also means that the directions are substantially parallel, that is, there is a difference of, for example, a few percent.

[0022] In the following explanation, unless otherwise specified, ordinal numbers such as "first" and "second" do not refer to the number or order of the elements (components, parts, events, etc.) to which the ordinal numbers are attached, but are used to avoid confusion among multiple elements and to distinguish each of the multiple elements from the other elements. In the following explanation, when the word "insulation" is used, it means "electrical insulation." An insulating material has a volume resistivity of 1 x 10 6 Ωm or more, more preferably 1×10 7 Ωm or more, more preferably 1×10 10 It is preferable that the material be made of a material with a resistance of Ωm or more.

[0023] (Embodiment) [1. General Description of the Power Storage Device 1] Fig. 1 is a perspective view showing the configuration of an energy storage device 1 according to an embodiment. Fig. 1 shows an energy storage unit 10 removed from a case body 610. Fig. 2 is an exploded perspective view of the energy storage unit 10 according to an embodiment. Fig. 2 shows four energy storage elements 100 and five holders 200, which are arranged consecutively in the Y-axis direction, out of the plurality of energy storage elements 100 and the plurality of holders 200 included in the energy storage unit 10.

[0024] When describing the two energy storage elements 100 at the ends in the negative Y-axis direction of the four energy storage elements 100 shown in Fig. 2 while distinguishing between them, the energy storage element 100 at the positive Y-axis direction of the two energy storage elements 100 will be referred to as the first energy storage element 100A, and the energy storage element 100 at the negative Y-axis direction will be referred to as the second energy storage element 100B. Furthermore, of the five holders 200 shown in Fig. 2, the holder 200 disposed between the first energy storage element 100A and the second energy storage element 100B will be referred to as the first holder 200A, and the holder 200 disposed in the positive Y-axis direction of the first energy storage element 100A will be referred to as the second holder 200B. The holder 200 disposed in the negative Y-axis direction of the second energy storage element 100B will be referred to as the third holder 200C. That is, in the present embodiment, first energy storage element 100A is arranged between first holder 200A and second holder 200B, and second energy storage element 100B is arranged between first holder 200A and third holder 200C. The Y-axis direction is an example of the first direction.

[0025] The power storage device 1 is a device that can charge with electricity from an external source and discharge electricity to an external source. The power storage device 1 is, for example, a battery module (battery assembly) used for power storage or power supply purposes. Specifically, the power storage device 1 is used as a battery for driving or starting the engine of a moving object such as an automobile, motorcycle, personal watercraft, ship, snowmobile, agricultural machinery, construction machinery, automatic guided vehicle (AGV), or electric railway vehicle. Examples of the automobile include an electric vehicle (EV), a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), and a fossil fuel (gasoline, diesel, liquefied natural gas, etc.) vehicle. Examples of the electric railway vehicle include a train, a monorail, a linear motor car, and a hybrid train equipped with both a diesel engine and an electric motor. The power storage device 1 can also be used as a stationary battery for home or business use.

[0026] 1, the energy storage device 1 includes an energy storage unit 10 and a case 600 that houses the energy storage unit 10. In addition to the above components, the energy storage device 1 may also include a bus bar unit including a plurality of bus bars connected to the plurality of energy storage elements 100, and electrical devices such as a circuit board and a relay that monitor or control the charge state, discharge state, etc. of the energy storage unit 10.

[0027] In this embodiment, the energy storage unit 10 is a battery module having a plurality of energy storage elements 100. The plurality of energy storage elements 100 are stacked (arranged) in the Y-axis direction and are also referred to as a "cell stack," for example. Specifically, the energy storage unit 10 according to this embodiment includes a plurality of (34 in this embodiment) energy storage elements 100, a holder 200 arranged between two adjacent energy storage elements 100 in the Y-axis direction, and holders 250 arranged outside each of the energy storage elements 100 at both ends in the Y-axis direction. The holders 200 are also referred to as "inter-cell holders," for example. In this embodiment, 33 holders 200 are arranged for the 34 energy storage elements 100. The holders 250 are also referred to as "end holders," for example. In this embodiment, the holders 200 and 250 have the function of holding one or more energy storage elements 100 arranged along the holder 200 or 250. Details of the holder 200 and its surrounding configuration will be described later with reference to FIGS. 3 to 5.

[0028] The energy storage unit 10 has a generally rectangular parallelepiped shape that is long in the Y-axis direction, with the plurality of energy storage elements 100, the plurality of holders 200, and the pair of holders 250 arranged in the Y-axis direction. Conductive members such as bus bars (not shown) are connected to the terminals 140 of the plurality of energy storage elements 100 included in the energy storage unit 10. The rectangular parallelepiped here refers to a hexahedron with all faces formed into rectangles or squares.

[0029] In this embodiment, the energy storage unit 10 is a non-constraint type module that does not include constraint members (end plates, side plates, etc.) that constrain the plurality of energy storage elements 100 in the Y-axis direction. However, the energy storage unit 10 may include constraint members that constrain the plurality of energy storage elements 100 and the plurality of holders 200 and 250 in the Y-axis direction.

[0030] The energy storage element 100 is a secondary battery (single cell), more specifically, a nonaqueous electrolyte secondary battery such as a lithium-ion secondary battery. As shown in FIG. 2 , the energy storage element 100 includes a flat rectangular parallelepiped (rectangular) container 110. The container 110 contains an electrode assembly, a current collector, an electrolyte, and other components (not shown). For example, a wound electrode assembly formed by winding an electrode plate and a separator may be used as the electrode assembly. Alternatively, a laminated (stacked) electrode assembly formed by stacking multiple flat electrode plates, or an electrode assembly having a bellows-like structure formed by repeatedly folding long strip-shaped electrode plates, may be used. The electrolyte contained in the container 110 may be of any type, and various types may be selected as long as it does not impair the performance of the energy storage element 100. The energy storage element 100 may be a secondary battery other than a nonaqueous electrolyte secondary battery, or a capacitor. The energy storage element 100 may also be a primary battery. The energy storage element 100 may be a battery using a solid electrolyte. The energy storage element 100 may be a pouch-type energy storage element. The shape of the energy storage element 100 is not limited to the above-mentioned rectangular shape, and may be other shapes such as a polygonal column, a cylindrical column, an elliptical column, or an oblong column.

[0031] 2, the container 110 is a rectangular parallelepiped case having a pair of long sides 111, a pair of short sides 112, and a bottom surface 113 formed by the container body, and a terminal arrangement surface 130 formed by a cover plate. After the electrode assembly and the like are housed inside the container body, the container body and the cover plate are welded together or the like to seal the interior of the container 110. The material of the container 110 is not particularly limited, but is preferably a weldable metal such as stainless steel, aluminum, an aluminum alloy, iron, or plated steel sheet.

[0032] The energy storage element 100 includes terminals 140 arranged in the Z-axis direction. The Z-axis direction is an example of a second direction. The terminals 140 are electrically connected to an electrode assembly housed in the container 110. More specifically, a pair of terminals 140 are arranged to protrude in the positive direction of the Z-axis from a terminal arrangement surface 130 of the container 110. A gas exhaust valve 131 is further provided on the terminal arrangement surface 130. One of the pair of terminals 140 is electrically connected to the positive electrode of the electrode assembly, and the other is electrically connected to the negative electrode of the electrode assembly. The terminals 140 are formed of a metal such as aluminum, an aluminum alloy, copper, or a copper alloy.

[0033] The holder 200 includes a holder main body 201 facing the energy storage elements 100 in the Y-axis direction. The holder main body 201 includes a side wall portion 202 facing the energy storage elements 100 in the X-axis direction. In this embodiment, the side wall portion 202 is arranged to extend from an end of the holder main body 201 in the X-axis direction in both the positive and negative Y-axis directions, thereby facing the two energy storage elements 100 held by the holder 200 in the X-axis direction. The holder 200 further includes a bottom wall portion 203 facing the bottom surface 113 of the energy storage elements 100. The bottom wall portion 203 is arranged to extend from an end of the holder main body 201 in the negative Z-axis direction in both the positive and negative Y-axis directions, thereby facing the two energy storage elements 100 held by the holder 200 in the Z-axis direction.

[0034] In the present embodiment, the side wall portion 202 is composed of a plurality of portions separated in the Z-axis direction, but the side wall portion 202 may be composed of a single wall portion that is continuous in the Z-axis direction. The side wall portion 202 may have any size and shape that does not interfere with the side wall portion 202 of the holder 200 that includes the side wall portion 202 and the side wall portion 202 of another holder 200 that is adjacent to the holder 200. Specifically, when two holders 200 lined up in the Y-axis direction are combined, the side wall portions 202 of the two holders 200 may have any size and shape that does not interfere with the combination of the two holders 200.

[0035] The holder 200 has the bottom wall 203 and the pair of side walls 202, etc., and thereby functions to hold two energy storage elements 100. The holder 200 further has protrusions (210A in FIG. 3, etc.) that connect adjacent holders 200 in the Y-axis direction. Details of the protrusions will be described later with reference to FIGS. 3 to 5.

[0036] The holder 250 is an end holder that is arranged at the end of the energy storage unit 10 in the Y-axis direction. The holder 250 holds the energy storage elements 100 that are arranged in either the positive Y-axis direction or the negative Y-axis direction of the holder 250. The configuration of the holder 250 is almost the same as that of the holder 200, except that the number of energy storage elements 100 that can be held is one, and therefore a description of the configuration of the holder 250 will be omitted.

[0037] The holder 200 and the holder 250 are formed of an insulating material such as resin, and also function as an insulating member that insulates the energy storage device 100 held by the holder 200 or the holder 250 from other members.

[0038] The case 600 is a container having a substantially rectangular parallelepiped (box-like) shape that houses the power storage unit 10. The case 600 is disposed outside the power storage unit 10 and protects the power storage unit 10 from impacts and the like. The case 600 is formed of a metal member such as aluminum, aluminum alloy, stainless steel, iron, or plated steel sheet. In this embodiment, the case 600 is formed by die-casting aluminum (aluminum die-casting). Instead of the case 600, a case formed of an insulating member such as a resin material may be used as the case that houses the power storage unit 10.

[0039] As shown in FIG. 1 , the case 600 has a case main body 610. The case main body 610 is a housing (enclosure) having an opening 610a formed in the positive direction of the Z axis and sized to allow the power storage unit 10 to be inserted therein. The case main body 610 includes a case side wall 611 facing the power storage unit 10 in the X axis direction, a case side wall 612 facing the power storage unit 10 in the Y axis direction, and a case bottom wall 615 supporting the power storage unit 10 from the negative direction of the Z axis. The X axis direction is an example of a third direction. The case 600 may further include a lid (not shown) that closes the opening 610a of the case main body 610.

[0040] [2. Configuration of the holder 200 and its surroundings] Next, the configuration of the holder 200 and its surroundings will be described with reference to Figures 3 to 5 in addition to Figures 1 and 2. Below, attention will be focused on the first holder 200A, the second holder 200B, and the third holder 200C among the multiple holders 200, and the configuration of these holders 200 and their surroundings will be described.

[0041] FIG. 3 is a perspective view showing a configuration of a holder 200 and its surroundings according to the embodiment. In FIG. 3, the outlines of the first energy storage element 100A and the second energy storage element 100B are roughly indicated by dotted lines, and the energy storage elements 100 and holders 200 adjacent to each other in the Y-axis direction are shown separated in the Y-axis direction. FIG. 4 is a first partial perspective view showing a portion of the energy storage unit 10 according to the embodiment. In FIG. 4, the first holder 200A, the second holder 200B, and the third holder 200C are shown in an assembled state. FIG. 5 is a second partial perspective view showing a portion of the energy storage unit 10 according to the embodiment. In FIG. 5, the portion of the energy storage unit 10 is shown from an angle different from that shown in FIG. 4.

[0042] 3 to 5, the energy storage unit 10 according to the embodiment includes a first holder 200A, a second holder 200B, and a third holder 200C. Specifically, the third holder 200C, the first holder 200A, and the second holder 200B are successively arranged in this order from the negative Y-axis direction. These three holders 200 are arbitrarily selected from the plurality of holders 200 included in the energy storage device 1 according to the embodiment and are successively arranged on the Y-axis.

[0043] In the present embodiment, first energy storage element 100A is disposed between first holder 200A and second holder 200B. That is, first energy storage element 100A is held by first holder 200A and second holder 200B. Second energy storage element 100B is disposed between first holder 200A and third holder 200C. That is, second energy storage element 100B is held by first holder 200A and third holder 200C.

[0044] As described above, the holder 200 according to this embodiment includes the holder main body 201. The holder main body 201 includes sidewalls 202. The holder main body 201 faces the energy storage elements 100 in the Y-axis direction, and the sidewalls 202 face the energy storage elements 100 in the X-axis direction. In this embodiment, the sidewalls 202 are arranged at the end of the holder main body 201 facing the positive direction of the X-axis and at the end of the holder main body 201 facing the negative direction of the X-axis. That is, the holder 200 includes a pair of sidewalls 202, and the energy storage elements 100 are arranged between the pair of sidewalls 202. More specifically, the holder 200 holds two energy storage elements 100 arranged on both sides of the holder main body 201 in the Y-axis direction. In other words, the pair of sidewalls 202 sandwich the two energy storage elements 100 in the X-axis direction. Therefore, the two energy storage elements 100 are arranged between the pair of sidewalls 202 arranged apart in the X-axis direction.

[0045] More specifically, in the present embodiment, first holder 200A includes first holder main body 201A and first side wall 202A. First holder main body 201A faces long side surfaces 111 (see FIG. 2) of first energy storage element 100A and second energy storage element 100B in the Y-axis direction. First side wall 202A faces short side surfaces 112 (see FIG. 2) of first energy storage element 100A and second energy storage element 100B in the X-axis direction. Second holder 200B includes second holder main body 201B and second side wall 202B. Second holder main body 201B faces long side surface 111 of first energy storage element 100A in the Y-axis direction. Second side wall 202B faces short side surface 112 of first energy storage element 100A in the X-axis direction. Third holder 200C includes third holder main body 201C and third side wall 202C. Third holder main body 201C faces long side surface 111 of second energy storage element 100B in the Y-axis direction. Third side wall 202C faces short side surface 112 of second energy storage element 100B in the X-axis direction.

[0046] In the electricity storage unit 10 having such a configuration, as shown in Figures 4 and 5, the first holder 200A is connected to the second holder 200B. The first holder 200A is further connected to the third holder 200C. That is, the second holder 200B and the third holder 200C are connected to each other via the first holder 200A. More specifically, the configuration of the electricity storage device 1 according to this embodiment is described as follows, for example.

[0047] The energy storage device 1 according to this embodiment includes a plurality of energy storage elements 100 lined up in the Y-axis direction, and a plurality of holders 200 lined up in the Y-axis direction, each of which holds one or more of the plurality of energy storage elements 100. The plurality of holders 200 include a first holder 200A and a second holder 200B arranged on one side of the first holder 200A in the Y-axis direction (in this embodiment, the positive direction of the Y-axis; the same applies below). Each of the plurality of energy storage elements 100 includes a terminal 140 in the Z-axis direction, which is perpendicular to the Y-axis direction.

[0048] As shown in FIGS. 3 to 5, the first holder 200A includes a first holder main body 201A, a first protruding portion 210A protruding from the first holder main body 201A, and a first convex portion 211A provided on the first protruding portion 210A. The first protruding portion 210A is disposed at an end of the first holder main body 201A in the X-axis direction, which is perpendicular to the Y-axis direction and the Z-axis direction. The first convex portion 211A protrudes from the first protruding portion 210A to one side in the Y-axis direction. The second holder 200B includes a second holder main body 201B, a second protruding portion 210B protruding from the second holder main body 201B, and a second opening 211B penetrating the second protruding portion 210B in the Y-axis direction. The first convex portion 211A is inserted into and penetrates the second opening 211B.

[0049] As described above, in the energy storage device 1 according to the present embodiment, the first holder 200A is provided with a first protrusion 211A that protrudes to one side in the Y-axis direction, which is the arrangement direction of the plurality of energy storage elements 100, and the second holder 200B is provided with a second opening 211B into which the first protrusion 211A is inserted. That is, two holders 200 adjacent to each other in the Y-axis direction are connected. Therefore, for example, movement of the first holder 200A in the Z-axis direction is restricted by the second holder 200B. This allows, for example, the plurality of energy storage elements 100 to be arranged in the Y-axis direction with high precision without using any other members.

[0050] In the power storage unit 10, connecting at least the first holder 200A and the second holder 200B improves the rigidity of the power storage unit 10. This prevents the power storage unit 10 from bending in a direction perpendicular to the Y-axis direction due to, for example, vibration, impact, or its own weight. In other words, connecting at least two holders 200 provided in the power storage unit 10 prevents bending of the power storage unit 10 caused by vibration or the like, and as a result, prevents problems such as the holder 200 colliding with the inner surface of the case 600 or a part of the power storage unit 10 being disposed floating above the case bottom wall 615. In other words, the effect of preventing bending of the power storage unit 10 can be obtained without using a restraining member or the like.

[0051] Furthermore, the first convex portion 211A is provided on the first protruding portion 210A protruding from the first holder body 201A, and the second opening portion 211B is provided on the second protruding portion 210B protruding from the second holder body 201B. That is, the first convex portion 211A is provided on a portion (first protruding portion 210A) protruding from the first holder body 201A that does not need to play a role in holding the energy storage elements 100, and the second opening portion 211B is provided on a portion (second protruding portion 210B) protruding from the second holder body 201B that does not need to play a role in holding the energy storage elements 100. Therefore, for example, there is a high degree of freedom in the size and shape of the first convex portion 211A and the second opening portion 211B. Furthermore, the first convex portion 211A is arranged so as to penetrate the second opening portion 211B shown in FIGS. 4 and 5. That is, the tip of the first protrusion 211A is exposed to the outside from the second opening 211B in the insertion direction (positive direction of the Y axis) of the first protrusion 211A. In other words, the length of the first protrusion 211A in the protruding direction (positive direction of the Y axis) is longer than the thickness of the second protrusion 210B in the Y axis direction. Therefore, compared to when the second opening 211B is a hole with a bottom, the length of the first protrusion 211A in the Y axis direction can be made longer. This makes it less likely for the first protrusion 211A to come off the second opening 211B, for example. As a result, for example, the effect of suppressing bending of the energy storage unit 10 can be maintained. Furthermore, by checking whether the tip of the first protrusion 211A is exposed to the outside from the second opening 211B, it can be checked whether the first protrusion 211A is properly inserted into the second opening 211B. That is, it is easy to check whether the first holder 200A and the second holder 200B are properly combined. Thus, the electricity storage device 1 according to this embodiment is a electricity storage device with a simple configuration and improved reliability.

[0052] More specifically, as shown in FIGS. 2 to 5, the first protrusion 210A protrudes in the X-axis direction from the end of the first holder body 201A in the X-axis direction. For example, the first protrusion 210A provided at the end of the first holder body 201A in the positive X-axis direction protrudes in the positive X-axis direction from that end. That is, the second protrusion 210B connected to the first protrusion 210A also protrudes in the X-axis direction from the end of the second holder body 201B in the X-axis direction. This allows the first protrusion 210A and the second protrusion 210B to be arranged in a manner that does not consume space in the Z-axis direction of the energy storage unit 10. Therefore, for example, the presence of the first protrusion 210A is unlikely to interfere with work such as joining the terminal 140 to a conductive member (not shown) such as a bus bar. This contributes to, for example, improving the accuracy of joining the terminal 140 to the conductive member. Arranging the first protrusion 210A and the second protrusion 210B in a manner that does not consume space in the Z-axis direction of the energy storage unit 10 contributes to reducing the width of the energy storage unit 10 in the Z-axis direction (in other words, reducing its height).

[0053] In the present embodiment, the first holder 200A holds the first energy storage element 100A of the plurality of energy storage elements 100. The first holder main body 201A includes a first side wall portion 202A facing a side surface (short side surface 112) of the first energy storage element 100A in the X-axis direction. The first protrusion portion 210A is provided on the first side wall portion 202A. More specifically, as shown in FIGS. 2 to 5, the first holder 200A according to the present embodiment holds the first energy storage element 100A and the second energy storage element 100B. Therefore, the first side wall portion 202A faces the short side surfaces 112 (see FIG. 2) of the first energy storage element 100A and the second energy storage element 100B.

[0054] As described above, in the present embodiment, the first protruding portion 210A is provided to protrude from the first side wall portion 202A of the first holder main body 201A. That is, the first protruding portion 210A is supported by the first side wall portion 202A that forms a relatively wide surface. Therefore, the first protruding portion 210A is supported more stably.

[0055] In this embodiment, the multiple holders 200 further include a third holder 200C disposed on the other side of the first holder 200A in the Y-axis direction (in this embodiment, the negative Y-axis direction). As shown in FIGS. 3 to 5, the first holder 200A further includes a third protrusion 213A disposed at the end of the first holder main body 201A in the X-axis direction and protruding from the first holder main body 201A, and a first opening 214A provided in the third protrusion 213A. The third holder 200C includes a third holder main body 201C, a fourth protrusion 210C protruding from the third holder main body 201C, and a third convex portion 211C provided in the fourth protrusion 210C. The third convex portion 211C is inserted into the first opening 214A of the first holder 200A. More specifically, in this embodiment, as shown in FIGS. 4 and 5, the third protrusion 211C is inserted into the first opening 214A and passes through the first opening 214A.

[0056] As described above, in the present embodiment, the first holder 200A further includes a third protrusion 213A protruding from the first holder main body 201A, and the third convex portion 211C of the third holder 200C is inserted into the first opening 214A provided in the third protrusion 213A. As a result, the first holder 200A and the second holder 200B and the third holder 200C, which sandwich the first holder 200A in the Y-axis direction, are connected to each other. This allows the multiple energy storage elements 100 to be aligned in the Y-axis direction with even greater precision. This further reliably suppresses deflection of the energy storage unit 10, which includes the multiple energy storage elements 100 and the multiple holders 200, in a direction perpendicular to the Y-axis direction.

[0057] In this embodiment, as shown in FIGS. 3 to 5, the first protruding portion 210A and the third protruding portion 213A are disposed at different positions in the Z-axis direction on the first holder 200A.

[0058] In this way, in the first holder 200A, the first protrusion 210A and the third protrusion 213A are positioned at different positions from each other in the Z-axis direction, so that, for example, the third convex portion 211C inserted into the first opening 214A of the third protrusion 213A is prevented from interfering with the first protrusion 210A.

[0059] As described above, the end portion in the X-axis direction of the first holder main body 201A of the first holder 200A is provided with a first protrusion 210A (first convex portion 211A) arranged at the end portion in the positive direction of the Z-axis, and a third protrusion 213A (first opening 214A) arranged at the end portion in the negative direction of the Z-axis (see FIGS. 2 to 5). The end portion in the X-axis direction of the second holder main body 201B of the second holder 200B is provided with a second protrusion 210B (second opening 211B) arranged at the end portion in the positive direction of the Z-axis, and a fifth protrusion 216B (second convex portion 217B) arranged at the end portion in the negative direction of the Z-axis (see FIGS. 3 to 5). The third holder 200C has the same structure as the second holder 200B. That is, the end of the third holder body 201C of the third holder 200C in the X-axis direction is provided with a sixth protrusion 218C (third opening 219C) arranged at the end in the positive Z-axis direction, and a fourth protrusion 210C (third convex portion 211C) arranged at the end in the negative Z-axis direction (see Figures 3 and 4).

[0060] That is, the multiple holders 200 included in the power storage device 1 according to this embodiment include two types of holders 200 that are different in structure from each other. Specifically, the multiple holders 200 include a holder 200 that has a structure that includes a convex portion at an end in the X-axis direction facing the positive Z-axis direction and an opening at an end in the X-axis direction facing the negative Z-axis direction, i.e., a holder 200 that has the same structure as the first holder 200A. The multiple holders 200 further include a holder 200 that has a structure that includes an opening at an end in the X-axis direction facing the positive Z-axis direction and a convex portion at an end in the X-axis direction facing the negative Z-axis direction, i.e., a holder 200 that has the same structure as the second holder 200B and the third holder 200C.

[0061] For example, as shown in FIG. 3, assume that a holder 200 having the same structure as a first holder 200A is referred to as a first-type holder 260, and a holder 200 having the same structure as a second holder 200B and a third holder 200C is referred to as a second-type holder 270. In this case, in the energy storage device 1 according to the present embodiment, the first-type holders 260 and the second-type holders 270 are alternately arranged among the multiple holders 200 arranged in the Y-axis direction (see FIGS. 1 and 4). As a result, two holders 200 arranged in the Y-axis direction among the multiple holders 200 are connected by inserting the protrusion of one holder into the opening of the other holder. Furthermore, as shown in FIGS. 1, 4, and 5, the connecting portions of two holders 200 arranged in the Y-axis direction are not aligned on a straight line parallel to the Y-axis direction, but are aligned so as to be alternately positioned on one side and the other side in the Z-axis direction. This efficiently suppresses deflection of the energy storage unit 10. For example, consider a case where the energy storage unit 10 is about to bend so that the center of the energy storage unit 10 in the Y-axis direction is displaced in the positive direction of the Z-axis. In this case, the connecting portions of the two holders 200 in the energy storage unit 10 are aligned in the Y-axis direction and are alternately positioned on one side and the other side in the Z-axis direction. Therefore, bending in the positive direction of the Z-axis is more effectively suppressed than when the connecting portions are aligned on a straight line parallel to the Y-axis direction.

[0062] 1, in this embodiment, each of the two holders 250 serving as end holders has an opening or a protrusion that is connected to the protrusion or opening of the holder 200 adjacent to the holder 250. Therefore, in all of the holders (33 holders 200 and 2 holders 250) included in the energy storage unit 10 according to this embodiment, two adjacent holders 200, and adjacent holders 200 and holders 250 are connected to each other.

[0063] 1 to 5 show the connection structure of the multiple holders 200 and 250 on the side surface of the power storage unit 10 in the positive X-axis direction, but a similar connection structure is also provided on the side surface of the power storage unit 10 in the negative X-axis direction. That is, at the end of the power storage unit 10 in the negative X-axis direction, two holders 200 lined up in the Y-axis direction are connected by inserting a convex portion of one of the holders 200 into and passing through an opening of the other holder 200. Similarly, the holders 200 and 250 lined up in the Y-axis direction are connected by inserting a convex portion of one of the holders into and passing through an opening of the other holder 200.

[0064] [3. Explanation of Modifications] Although the energy storage device 1 according to the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment. The embodiment disclosed herein is an example in all respects, and the scope of the present invention includes all modifications within the meaning and scope of the claims.

[0065] In the above embodiment, the first holder 200A and the second holder 200B are connected to each other, and the first holder 200A and the third holder 200C are connected to each other. However, this is not essential. For example, the first holder 200A may be connected only to the second holder 200B. Even in this case, the first holder 200A and the second holder 200B can restrict the movement of each other at least at the connection portion of the energy storage unit 10 between the first holder 200A and the second holder 200B. This contributes to arranging the plurality of energy storage elements 100 accurately in the Y-axis direction and to suppressing bending of the energy storage unit 10 in a direction perpendicular to the Y-axis direction.

[0066] That is, only some (two or more) of the holders 200 included in the energy storage unit 10 according to the embodiment may be connected by inserting the protrusions into the openings. In this case, from the viewpoint of arranging the plurality of energy storage elements 100 accurately in the Y-axis direction and / or from the viewpoint of suppressing bending of the energy storage unit 10, it is preferable that the some be located at the center in the Y-axis direction of the energy storage unit 10. That is, the first holder 200A and the second holder 200B according to the embodiment are preferably located at the center in the Y-axis direction of the energy storage unit 10.

[0067] The first protrusion 210A of the first holder 200A does not necessarily protrude in the X-axis direction from the end of the first holder main body 201A in the X-axis direction. For example, the first protrusion 210A may protrude in the Z-axis direction or the Y-axis direction from the end of the first holder main body 201A in the X-axis direction. When the first protrusion 210A protrudes in the Y-axis direction, for example, a part of the side wall 202 may be treated as the first protrusion 210A. In either case, the first protrusion 210A may include a first convex portion 211A that can be inserted into and penetrated by the second opening 211B of the second holder 200B. However, from the viewpoint of, for example, improving the degree of freedom in the size and shape of the first convex portion 211A, it is preferable that the first protrusion 210A protrude in the X-axis direction from the end of the first holder main body 201A in the X-axis direction.

[0068] It is also conceivable to dispose the first protrusion 210A, for example, at the end of the first holder body 201A in the positive Z-axis direction or the end of the first holder body 201A in the negative Z-axis direction. However, if the first protrusion 210A is disposed at the end of the first holder body 201A in the positive Z-axis direction, the first protrusion 210A may interfere with, for example, joining the terminal 140 to a conductive member (not shown) such as a bus bar. If the first protrusion 210A is disposed at the end of the first holder body 201A in the negative Z-axis direction, the first protrusion 210A may prevent, for example, the bottom surface of the holder 200 (the surface of the bottom wall 203 in the negative Z-axis direction) from being stably supported by the case bottom wall 615 (see FIG. 1). Therefore, from the viewpoint of preventing the occurrence of the various problems described above, it is preferable that the first protrusion 210A be provided at the end of the first holder body 201A in the X-axis direction.

[0069] The holder 200 does not necessarily have to hold two energy storage elements 100. The holder 200 only needs to hold at least one energy storage element 100. That is, the side wall portion 202 of the holder 200 may be disposed so as to extend from an end of the holder main body 201 in the X-axis direction to only one side in the Y-axis direction. In this case, the bottom wall portion 203 of the holder 200 may be disposed so as to extend from an end of the holder main body 201 in the negative Z-axis direction to only that one side in the Y-axis direction. Even in this case, the first holder 200A can be provided with a first protruding portion 210A, and the second holder 200B can be provided with a second protruding portion 210B. That is, the first holder 200A and the second holder 200B are connected to each other by inserting a first convex portion 211A provided on the first protruding portion 210A into and passing through a second opening 211B provided on the second protruding portion 210B.

[0070] The energy storage unit 10 does not need to include holders 250 disposed at both ends in the Y-axis direction. For example, spacers that do not have the function of holding the energy storage elements 100 may be provided at both ends in the Y-axis direction of the energy storage unit 10. End plates for restraining the plurality of energy storage elements 100 and the plurality of holders 200 in the Y-axis direction may be provided at both ends in the Y-axis direction of the energy storage unit 10. If the end plates are made of metal, it is preferable to provide an insulating member between the end plates and the energy storage elements 100 adjacent to the end plates.

[0071] The energy storage device 1 does not need to include the case 600. For example, an energy storage unit 10 including a plurality of energy storage elements 100 and a plurality of holders 200 may be housed as the energy storage device 1 in some kind of device, a rack, or the like.

[0072] Any combination of the components of the above-described embodiment and its modifications is also included within the scope of the present invention. [Industrial Applicability]

[0073] The present invention can be applied to an electricity storage device or the like that includes an electricity storage element such as a lithium ion secondary battery. [Explanation of symbols]

[0074] 1. Energy storage device 100 Energy storage element 100A first storage element 100B second storage element 200, 250 holder 200A First Holder 200B Second holder 200C Third Holder 201 Holder body 201A First holder body 201B Second holder body 201C Third holder body 202 Side wall 202A First side wall part 202B Second side wall part 202C Third side wall section 203 bottom wall 210A First protrusion 210B Second protrusion 210C Fourth protrusion 211A First convex part 211B Second opening 211C third convex part 213A Third protrusion 214A First opening 216B Fifth protrusion 217B Second convex part 218C Sixth Protrusion 219C Third opening 260 First タイプホルダ 270 The second タイプホルダ

Claims

1. A plurality of storage elements arranged in a first direction; a plurality of holders arranged in the first direction, each of which holds one or more of the plurality of energy storage elements; the plurality of holders include a first holder and a second holder disposed on one side of the first holder in the first direction, each of the plurality of energy storage elements includes a terminal in a second direction perpendicular to the first direction; the first holder includes a first holder main body, a first protruding portion protruding from the first holder main body, and a first convex portion provided on the first protruding portion, the first protrusion is disposed at an end of the first holder body in a third direction perpendicular to the first direction and the second direction, the first convex portion protrudes from the first protruding portion to one side in the first direction, the second holder includes a second holder main body, a second protruding portion protruding from the second holder main body, and a second opening portion penetrating the second protruding portion in the first direction, the first protrusion is inserted into the second opening and penetrates the second opening; Energy storage device.

2. the first protrusion protrudes in the third direction from an end of the first holder body in the third direction; The power storage device according to claim 1 .

3. the first holder holds a first storage element among the plurality of storage elements, the first holder body includes a first side wall portion facing a side surface of the first energy storage element in the third direction, The first protrusion is provided on the first side wall. The electricity storage device according to claim 1 or 2.

4. the plurality of holders further includes a third holder disposed on the other side of the first holder in the first direction, the first holder further includes a third protruding portion disposed at an end of the first holder main body in the third direction and protruding from the first holder main body, and a first opening provided in the third protruding portion, the third holder includes a third holder main body, a fourth protruding portion protruding from the third holder main body, and a third convex portion provided on the fourth protruding portion, the third protrusion is inserted into the first opening. The electricity storage device according to claim 1 or 2.

5. the first protruding portion and the third protruding portion are disposed at positions different from each other in the second direction on the first holder. The power storage device according to claim 4.

Images