Energy Storage Module

Abstract

This electrical storage module is provided with: an array in which a plurality of electrical storage devices are arrayed in a third direction perpendicular to a first direction and a second direction, each electrical storage device having a first surface and a second surface opposite the first surface which are arranged in the first direction, the electrical storage device having a greater dimension in the second direction perpendicular to the first direction than in the first direction; a first restraining member which opposes the first surface of each electrical storage device, extends in the third direction, and restrains the array in the third direction; and a second restraining member which opposes the second surface of each electrical storage device, extends in the third direction, and restrains the array in the third direction. At least one of the first restraining member and the second restraining member has a hole comprising a recess recessed in the first direction or a through-hole penetrating through the restraining member in the first direction.

Description

[Technical field]

[0001] The present disclosure relates to an energy storage module. [Background technology]

[0002] As a power source that requires a high output voltage, for example for vehicles, etc., a power storage module in which multiple power storage devices (e.g., batteries) are connected in series is known. With regard to such a power storage module, for example, Patent Document 1 discloses a battery pack including multiple batteries, a pair of end plates arranged at both ends in the arrangement direction of the batteries, and a binding member (bind bar) that is stretched between the pair of end plates and binds the multiple batteries in the arrangement direction. In this battery pack, the batteries have a shape that is wider than they are high, and the pair of binding members sandwich the multiple batteries in the height direction. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-169270 A Summary of the Invention [Problem to be solved by the invention]

[0004] When constraining a battery whose width is greater than its height, a structure in which the pair of constraining members sandwich the battery in the height direction rather than in the width direction allows the constraining members to be made larger and stronger, but larger constraining members result in an increase in the mass of the energy storage module.

[0005] The present disclosure has been made in light of these circumstances, and one of its objectives is to provide a technique for reducing the weight of a restraining member included in an electricity storage module. [Means for solving the problem]

[0006] One aspect of the present disclosure is an energy storage module. The energy storage module includes an array in which a plurality of energy storage devices, each having a first surface and a second surface opposite the first surface and larger in a second direction perpendicular to the first direction than in the first direction in which the first and second surfaces are aligned, are arranged in a third direction perpendicular to the first and second directions, a first restraining member facing the first surface of each of the energy storage devices and extending in the third direction to restrain the array in the third direction, and a second restraining member facing the second surface of each of the energy storage devices and extending in the third direction to restrain the array in the third direction. At least one of the first restraining member and the second restraining member has a hole portion formed of a recess recessed in the first direction or a through hole penetrating the restraining member in the first direction.

[0007] Any combination of the above components and any conversion of the expression of the present disclosure between a method, an apparatus, a system, etc. are also valid as aspects of the present disclosure. Effect of the Invention

[0008] According to the present disclosure, it is possible to reduce the weight of the restraining member included in the energy storage module. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a perspective view of an electricity storage module according to a first embodiment. [Diagram 2] FIG. 2 is an exploded perspective view of the electricity storage module. [Diagram 3] FIG. 2 is a perspective view of the electricity storage device and a separator. [Figure 4A] 13 is a perspective view showing a state in which the separator and the second restraining member are fitted together. FIG. [Figure 4B] 11 is a cross-sectional view showing a separator and a second restraining member fitted together. FIG. [Diagram 5] 13 is a perspective view of a second restraining member included in the electricity storage module according to the second embodiment. FIG. [Figure 6] 13 is a perspective view showing a state in which the separator and the second restraining member are fitted together. FIG. [Figure 7] 13 is a perspective view showing how a second restraining member and a separator included in the electricity storage module according to the first modification are fitted together. FIG. [Figure 8] 13 is a perspective view of a second restraining member included in an electricity storage module according to a second modification. FIG. [Figure 9] 13 is a perspective view showing a state in which a second restraining member and a separator are fitted together. FIG. [Figure 10] 13 is a perspective view of a second restraining member included in an electricity storage module according to a third modification. FIG. [Figure 11] 13 is a perspective view showing a state in which a second restraining member and a separator are fitted together. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The present disclosure will be described below with reference to the drawings based on preferred embodiments. The embodiments are illustrative and do not limit the present disclosure, and all features and combinations thereof described in the embodiments are not necessarily essential to the present disclosure. The same or equivalent components, members, and processes shown in each drawing are given the same reference numerals, and duplicated descriptions are omitted as appropriate. In addition, the scale and shape of each part shown in each drawing are set for convenience to facilitate explanation, and are not to be interpreted as being limiting unless otherwise specified. In addition, when terms such as "first" and "second" are used in this specification or claims, unless otherwise specified, these terms do not represent any order or importance, but are intended to distinguish one configuration from another. In addition, some of the members that are not important in explaining the embodiment in each drawing are omitted.

[0011] (Embodiment 1) Fig. 1 is a perspective view of an energy storage module according to embodiment 1. Fig. 2 is an exploded perspective view of the energy storage module. The energy storage module 1 includes an array body 2, a first constraint member 4, a second constraint member 6, a heat conduction member 8, and a cooling plate 10.

[0012] The array 2 has a plurality of electricity storage devices 12, a plurality of separators 14, and a pair of end plates 16. FIG 3 is a perspective view of the electricity storage devices 12 and the separators 14.

[0013] Each power storage device 12 is, for example, a rechargeable secondary battery such as a lithium ion battery, a nickel-hydrogen battery, or a nickel-cadmium battery, or a capacitor such as an electric double layer capacitor. Power storage device 12 in this embodiment is a so-called prismatic battery, and has a housing 18 in the shape of a flat rectangular parallelepiped. Housing 18 is composed of an exterior can 20 and a sealing plate 22.

[0014] The exterior can 20 has a substantially rectangular opening on one side, and an electrode assembly, an electrolyte, etc. are accommodated in the exterior can 20 through this opening. The exterior can 20 has a bottom surface facing the opening, and four side surfaces connecting the opening and the bottom surface. Two of the four side surfaces are a pair of long side surfaces connected to two opposing long sides of the opening. Each long side surface is the surface with the largest area among the surfaces possessed by the exterior can 20, i.e., a main surface. The remaining two side surfaces excluding the two long side surfaces are a pair of short side surfaces connected to the short sides of the opening of the exterior can 20.

[0015] The exterior can 20 may be covered with an insulating film (not shown) such as a shrink tube. By covering the surface of the exterior can 20 with an insulating film, it is possible to suppress short circuits between adjacent power storage devices 12. It is also possible to suppress short circuits between the power storage devices 12 and the end plates 16, the first restraining members 4, and the second restraining members 6. A sealing plate 22 that closes the opening of the exterior can 20 and seals the exterior can 20 is fitted into the opening. The exterior can 20 and the sealing plate 22 are conductive and are made of metal such as aluminum, iron, stainless steel, etc. The exterior can 20 and the sealing plate 22 are joined together by, for example, a laser, friction stir welding, brazing, etc. Alternatively, the exterior can 20 and the sealing plate 22 are made of insulating resin.

[0016] A pair of output terminals 24 are disposed on the sealing plate 22. Specifically, a positive terminal 24a is provided near one end in the longitudinal direction of the sealing plate 22, and a negative terminal 24b is provided near the other end. Hereinafter, when there is no need to distinguish the polarities of the pair of output terminals 24, the positive terminal 24a and the negative terminal 24b will be collectively referred to as output terminals 24.

[0017] The sealing plate 22 on which the pair of output terminals 24 are arranged constitutes the first surface 12a of the power storage device 12. The bottom surface of the exterior can 20 constitutes the second surface 12b of the power storage device 12. The first surface 12a and the second surface 12b face each other. In the description of this embodiment, for convenience, the first surface 12a side of the power storage device 12 is defined as the vertically upper side, and the second surface 12b side of the power storage device 12 is defined as the vertically lower side. The long side and the short side of the exterior can 20 are defined as the long side and the short side of the power storage device 12, respectively. In the array 2, the surface on the first surface 12a side of the power storage device 12 is defined as the upper surface of the array 2, the surface on the second surface 12b side of the power storage device 12 is defined as the lower surface of the array 2, and the surface on the short side of the power storage device 12 is defined as the side of the array 2. The pair of output terminals 24 may not be arranged on the first surface 12a. For example, the pair of output terminals 24 may be disposed on the short side surfaces of the power storage device 12 .

[0018] These directions and positions are defined for convenience. Therefore, for example, a portion defined as an upper surface in this disclosure does not necessarily mean that it is located higher than a portion defined as a lower surface. Therefore, the first surface 12a is not necessarily located higher than the second surface 12b. In addition, hereinafter, the direction in which the first surface 12a and the second surface 12b are arranged is defined as a first direction A, the direction in which the pair of output terminals 24 are arranged is defined as a second direction B, and the direction in which the multiple power storage devices 12 are arranged (stacked) is defined as a third direction C. The first direction A, the second direction B, and the third direction C are perpendicular to each other.

[0019] The electricity storage device 12 has a valve portion 26 on the first surface 12a. The valve portion 26 is disposed between a pair of output terminals 24 on the sealing plate 22. The valve portion 26 is configured to open when the internal pressure of the housing 18 rises to a predetermined value or higher, thereby allowing the gas inside the housing 18 to be released. The valve portion 26 is configured, for example, with a thin-walled portion that is provided in a part of the sealing plate 22 and is thinner than other parts, and a linear groove formed on the surface of the thin-walled portion. In this configuration, when the internal pressure of the housing 18 rises, the thin-walled portion tears starting from the groove, causing the valve portion 26 to open.

[0020] The multiple energy storage devices 12 are arranged in the third direction C at a predetermined interval such that the long sides of adjacent energy storage devices 12 face each other. The energy storage devices 12 are arranged such that the first faces 12a face the same direction. Two adjacent energy storage devices 12 are arranged such that the positive electrode terminal 24a of one energy storage device 12 and the negative electrode terminal 24b of the other energy storage device 12 are adjacent to each other. The positive electrode terminal 24a and the negative electrode terminal 24b are connected in series via a bus bar (not shown). Note that the output terminals 24 of the same polarity of the multiple adjacent energy storage devices 12 may be connected in parallel with each other via a bus bar to form an energy storage device block, and the energy storage device blocks may be connected in series with each other.

[0021] The separator 14 is also called an insulating spacer, and is disposed between the opposing long sides of two adjacent power storage devices 12 to electrically insulate the two power storage devices 12 from each other. The separator 14 is made of, for example, a resin having insulating properties. Examples of the resin constituting the separator 14 include thermoplastic resins such as polypropylene (PP), polybutylene terephthalate (PBT), polycarbonate (PC), and Noryl (registered trademark) resin (modified PPE). A plurality of power storage devices 12 and a plurality of separators 14 are alternately stacked. In addition, the separator 14 is also disposed between the power storage device 12 and the end plate 16. This insulates the power storage device 12 from the end plate 16.

[0022] The separator 14 has a main body 28, a wall 30, and a plurality of protrusions 32. The main body 28 is flat and is interposed between the long side surfaces of two adjacent electric storage devices 12. The wall 30 extends in a third direction C from two side edges of the main body 28 aligned in the second direction B, and mainly covers the short side surfaces of the electric storage device 12. Some of the plurality of protrusions 32 protrude upward from the upper edge of the main body 28, and the remaining protrusions 32 protrude downward from the lower edge of the main body 28. The function of the protrusions 32 will be described in detail later. In this embodiment, the main body 28, the wall 30, and the plurality of protrusions 32 are integrally formed.

[0023] The pair of end plates 16 are disposed on both ends of the multiple power storage devices 12 in the third direction C. The multiple power storage devices 12 and the multiple separators 14 arranged side by side are sandwiched between the pair of end plates 16 in the third direction C. The end plates 16 are made of, for example, a metal plate or a resin plate. The end plates 16 are provided with screw holes 36 into which screws 34 serving as fixing members are screwed.

[0024] The first restraining member 4 and the second restraining member 6 are also called bind bars. The first restraining member 4 and the second restraining member 6 are arranged to face each other in the first direction A. The first restraining member 4 faces the first surface 12a of each power storage device 12 and extends in the third direction C. The second restraining member 6 faces the second surface 12b of each power storage device 12 and extends in the third direction C. An array body 2 is interposed between the first restraining member 4 and the second restraining member 6.

[0025] The first restraining member 4 has a first main body portion 38 and a pair of first arm portions 40. The first main body portion 38 is a rectangular plate-like body extending in the third direction C. The first main body portion 38 extends parallel to the first surface 12a of each of the power storage devices 12. When viewed from the first direction A, the outline of the first main body portion 38 and the outline of the upper surface of the array body 2 are substantially identical. The pair of first arm portions 40 extend from both ends of the first main body portion 38 in the third direction C toward the second restraining member 6. The pair of first arm portions 40 face each other in the third direction C. Each first arm portion 40 is provided with a through hole 42 through which the screw 34 is inserted.

[0026] The second restraining member 6 has a second main body portion 44 and a pair of second arm portions 46. The second main body portion 44 is a rectangular plate-like body extending in the third direction C. The second main body portion 44 extends parallel to the second surface 12b of each of the power storage devices 12. When viewed from the first direction A, the outline of the second main body portion 44 and the outline of the lower surface of the array body 2 are substantially identical. The pair of second arm portions 46 extend from both ends of the second main body portion 44 in the third direction C toward the first restraining member 4. The pair of second arm portions 46 face each other in the third direction C. Each second arm portion 46 is provided with a through hole 48 through which the screw 34 is inserted.

[0027] At least one of the first restraining member 4 and the second restraining member 6 is made of a single plate material. In this embodiment, both the first restraining member 4 and the second restraining member 6 are made of a single plate. The main body and the pair of arms can be formed, for example, by bending both ends of a metal plate. In this case, the arms are from the bending position to the tip, and the remaining parts are the main body. Note that the restraining member may be made of resin as long as a predetermined level of rigidity is obtained. At least one of the first restraining member 4 and the second restraining member 6 may be divided into multiple parts.

[0028] The energy storage module 1 is assembled, for example, as follows. That is, a plurality of energy storage devices 12 and a plurality of separators 14 are alternately arranged and sandwiched between a pair of end plates 16 in the third direction C to form an array 2. The array 2 is sandwiched between a first restraining member 4 and a second restraining member 6 in the first direction A. The first restraining member 4 is aligned so that the through hole 42 overlaps with the screw hole 36 of the end plate 16. The second restraining member 6 is aligned so that the through hole 48 overlaps with the screw hole 36 of the end plate 16. In this state, the screw 34 is inserted through the through holes 42, 48, and screwed into the screw hole 36.

[0029] The first restraining member 4 and the second restraining member 6 are connected to a pair of end plates 16, whereby the first restraining member 4 and the second restraining member 6 restrain the array body 2 in the third direction C. Each power storage device 12 is positioned in the third direction C by being fastened in the third direction C by the first restraining member 4 and the second restraining member 6. The first arm portion 40 and the second arm portion 46 may be fixed to the end plates 16 by welding or the like. Furthermore, the surfaces of the first restraining member 4 and the second restraining member 6 facing the array body 2 may be covered with an insulating sheet (not shown).

[0030] As an example, after these positioning steps are completed, a bus bar is attached to the output terminal 24 of each power storage device 12, and the output terminals 24 of the multiple power storage devices 12 are electrically connected to each other. For example, the bus bar is fixed to the output terminal 24 by welding. Thereafter, the upper surface of the array 2 is covered with a cover member (not shown). The cover member prevents condensed water, dust, and the like from coming into contact with the output terminals 24, the bus bar, the valve portion 26, and the like. The cover member is made of, for example, an insulating resin, and can be fixed to the upper surface of the array 2 by a known fixing structure (not shown) including screws or a known locking mechanism.

[0031] The first restraining member 4 and the second restraining member 6 have holes 50. In this embodiment, the holes 50 are configured as through holes that penetrate the main body of each restraining member in the first direction A. The holes 50 may also be configured as recesses that are recessed in the first direction A. By providing the first restraining member 4 with the holes 50, the weight of the first restraining member 4 can be reduced. By providing the second restraining member 6 with the holes 50, the weight of the second restraining member 6 can be reduced.

[0032] The first restraining member 4 of the present embodiment has three holes 50 extending in the third direction C in which the power storage devices 12 are arranged and overlapping with the multiple power storage devices 12. Each hole 50 overlaps with all the power storage devices 12 constituting the array 2. Each hole 50 may overlap only with some of the power storage devices 12. The three holes 50 are arranged at a predetermined interval in the second direction B. The holes 50 at both ends overlap with the output terminals 24 of the power storage devices 12 when viewed from the first direction A. The central hole 50 overlaps with the valve portion 26 of each power storage device 12 when viewed from the first direction A. This exposes the output terminals 24 and the valve portion 26 of each power storage device 12 to the outside. The number of holes 50 is not limited, and may be one or more.

[0033] The second restraint member 6 in this embodiment has three holes 50 that extend in the third direction C and overlap with the multiple power storage devices 12. Each hole 50 overlaps with all of the power storage devices 12 that constitute the array 2. Each hole 50 may overlap with only some of the power storage devices 12. The three holes 50 are arranged at predetermined intervals in the second direction B. A heat conductive member 8 is fitted into each hole 50.

[0034] The heat conducting member 8 is housed in the hole 50 and is in contact with the second surface 12b of each power storage device 12 so as to be able to exchange heat. For example, the heat conducting member 8 is in direct contact with the second surface 12b. The heat conducting member 8 is made of a material having a higher thermal conductivity than air. The heat conducting member 8 is preferably insulating. Also, the heat conducting member 8 is preferably flexible. As the heat conducting member 8, a known resin sheet having good thermal conductivity, such as acrylic rubber or silicone rubber, a known cooling gel, or the like can be used.

[0035] The cooling plate 10 is a mechanism for cooling the plurality of power storage devices 12. The cooling plate 10 is made of a material having high thermal conductivity such as aluminum. The array body 2 is placed on the main surface of the cooling plate 10 via the second restraining member 6, with the bottom surface, that is, the second restraining member 6 side, facing the cooling plate 10. In this state, the cooling plate 10 is in contact with the heat conductive member 8 so as to be able to exchange heat. For example, the heat conductive member 8 is in direct contact with the cooling plate 10. Each power storage device 12 is cooled by exchanging heat with the cooling plate 10 via the heat conductive member 8. The second restraining member 6 may also be in contact with the cooling plate 10 so as to be able to exchange heat. In this case, each power storage device 12 can exchange heat with the cooling plate 10 via the heat conductive member 8 and the second restraining member 6. The cooling plate 10 may be provided with a refrigerant pipe (not shown) through which a refrigerant such as water or ethylene glycol flows.

[0036] Preferably, heat transfer member 8 is sandwiched between array body 2 and cooling plate 10 and elastically deforms to fill gaps between second surfaces 12b of each power storage device 12 and cooling plate 10. This can improve the cooling efficiency of each power storage device 12.

[0037] As described above, each separator 14 has multiple protrusions 32 that protrude upward and downward. Each separator 14 has three protrusions 32 on the top and bottom. The three protrusions 32 that protrude upward are arranged to overlap with the three hole portions 50 of the first restraining member 4 when viewed from the first direction A, and fit into the respective hole portions 50. The three protrusions 32 that protrude downward are arranged to overlap with the three hole portions 50 of the second restraining member 6 when viewed from the first direction A, and fit into the respective hole portions 50.

[0038] Fig. 4A is a perspective view showing how separator 14 and second restraining member 6 are fitted together. Fig. 4B is a cross-sectional view showing separator 14 and second restraining member 6 fitted together. Figs. 4A and 4B show how second restraining member 6 and separator 14 are fitted together, but the same is true for the fitting of first restraining member 4 and separator 14. Note that second arm portion 46 is not shown in Fig. 4A.

[0039] When the protrusion 32 is inserted into the hole 50, it comes into contact with two inner surfaces 50B of the inner surfaces of the hole 50 that face each other in the second direction B. The dimension of the protrusion 32 in the second direction B is approximately equal to the distance between the two inner surfaces 50B, and the protrusion 32 inserted into the hole 50 is sandwiched between the two inner surfaces 50B in the second direction B.

[0040] As described above, the energy storage module 1 according to the present embodiment includes the array body 2, the first binding member 4, and the second binding member 6. The array body 2 has a structure in which a plurality of energy storage devices 12 are arranged. Each energy storage device 12 has a first surface 12a and a second surface 12b facing the first surface 12a, and is arranged in a third direction C perpendicular to the first direction A and larger in the second direction B perpendicular to the first direction A than in the first direction A in which the first surface 12a and the second surface 12b are arranged. The first binding member 4 faces the first surface 12a of each energy storage device 12 and extends in the third direction C to bind the array body 2 in the third direction C. The second binding member 6 faces the second surface 12b of each energy storage device 12 and extends in the third direction C to bind the array body 2 in the third direction C. Furthermore, the first restraining member 4 and the second restraining member 6 have a recess recessed in the first direction A or a hole 50 configured as a through hole penetrating the restraining member in the first direction A.

[0041] When the array 2 of the power storage devices 12, which is larger in the second direction B than in the first direction A, is sandwiched between a pair of restraining members, the structure in which the array 2 is sandwiched from the first direction A can increase the cross-sectional area of ​​each restraining member perpendicular to the third direction C compared to the case of sandwiching from the second direction B. This can increase the strength of the restraining member against the force in the third direction C generated by the expansion of each power storage device 12. In addition, the end plate 16 of this embodiment is made of a plate material whose dimension in the second direction B is longer than its dimension in the first direction A in accordance with the shape of the power storage device 12. Then, this end plate 16 is also sandwiched from the first direction A by the first restraining member 4 and the second restraining member 6. This can shorten the distance from the center point of the end plate 16 viewed from the third direction C to the end to which the restraining member of the end plate 16 is connected compared to the case of sandwiching the end plate 16 from the second direction B by a pair of restraining members. For this reason, the end plate 16 is less likely to bend. Therefore, it is possible to cope with an increase in the amount of expansion that accompanies an increase in the capacity of each power storage device 12.

[0042] However, increasing the size of each restraining member increases the mass of the energy storage module 1. In response to this, by providing the first restraining member 4 and the second restraining member 6 with the hole 50, the weight of each restraining member can be reduced, and an increase in the mass of the energy storage module 1 can be suppressed. If at least one of the first restraining member 4 and the second restraining member 6 has the hole 50, the weight of the restraining member having the hole 50 can be reduced, and ultimately the weight of the energy storage module 1 can be reduced.

[0043] Moreover, the energy storage device 12 of the present embodiment has a pair of output terminals 24 on the first surface 12a. In the array body 2, the energy storage devices 12 are arranged so that the first surfaces 12a face the same direction. Furthermore, the energy storage device 12 of the present embodiment has a valve portion 26 on the first surface 12a. Furthermore, the first restraining member 4 has a hole portion 50 formed by a through hole. Then, the hole portion 50 overlaps with the output terminal 24 and the valve portion 26 of each energy storage device 12 when viewed from the first direction A. By overlapping the hole portion 50 with the output terminal 24, it is possible to prevent the first restraining member 4 from interfering with the connection work between the output terminal 24 and the bus bar. Furthermore, since at least a part of the connection structure between the output terminal 24 and the bus bar can be accommodated in the hole portion 50, it is possible to reduce the size of the energy storage module 1. Furthermore, by overlapping the hole portion 50 with the valve portion 26, it is possible to prevent the first restraining member 4 from interfering with the exhaust from the valve portion 26. The hole 50 may overlap only the output terminal 24 or the valve portion 26 .

[0044] Further, the second restraining member 6 of the present embodiment has a hole 50 formed by a through hole. The energy storage module 1 includes a heat conducting member 8 housed in the hole 50 and in contact with the second surface 12b of each energy storage device 12 in a heat exchangeable manner. The array body 2 has an upper surface and a lower surface wider than the side surfaces. Therefore, when the upper surface of the array body 2 is covered with the first restraining member 4 and the lower surface of the array body 2 is covered with the second restraining member 6, it is difficult to thermally connect each energy storage device 12 to the restraining member equally due to the positional deviation of each energy storage device 12. Therefore, it is difficult to equalize the degree of heat transfer of each energy storage device 12 to the restraining member. In response to this, the heat conducting member 8 is disposed in the through hole as the hole 50 provided in the second restraining member 6, and each energy storage device 12 and the heat conducting member 8 are in contact with each other in a heat exchangeable manner, thereby suppressing the variation in the cooling efficiency of the plurality of energy storage devices 12. Furthermore, by providing through holes as holes 50 in first restraint member 4, the cooling efficiency of each power storage device 12 can be improved.

[0045] Moreover, the energy storage module 1 of the present embodiment includes a cooling plate 10 on which the array body 2 is placed via the second restraining member 6 and which is in contact with the heat conductive member 8 so as to be capable of heat exchange. This can further improve the cooling efficiency of each energy storage device 12. Also, each energy storage device 12 can be thermally connected to the cooling plate 10 only via the heat conductive member 8 fitted into the hole portion 50, without the restraining member. On the other hand, when a restraining member without a hole portion 50 is used, in order to cool each energy storage device 12 with the cooling plate 10 while suppressing the cooling variation for each energy storage device 12, it is necessary to interpose a heat conductive member between the restraining member and the cooling plate 10. Therefore, a laminated structure of a heat conductive member and a restraining member is interposed between the array body 2 and the cooling plate 10. Therefore, according to the present embodiment, the number of interfaces between each member interposed between each energy storage device 12 and the cooling plate 10 can be reduced compared to the case where a restraining member without a hole portion 50 is interposed between each energy storage device 12 and the cooling plate 10. This also enhances the efficiency of cooling each electricity storage device 12. Furthermore, since the internal space of hole 50 can be used as a space for accommodating a heat conductive member, electricity storage module 1 can be made smaller.

[0046] Moreover, the array 2 of the present embodiment has a separator 14 that is disposed between two adjacent power storage devices 12 to provide insulation between the two power storage devices 12. The separator 14 has a protrusion 32 that fits into the hole 50. This makes it possible to restrict the relative displacement between the separator 14 and at least one of the first restraining member 4 and the second restraining member 6. This makes it possible to restrict the displacement of each power storage device 12, and improve the vibration resistance of the power storage module 1.

[0047] Moreover, the hole 50 of the present embodiment extends in the third direction C and overlaps with the plurality of electricity storage devices 12. This allows the number of holes 50 to be reduced, making it easier to manufacture the first binding member 4 and the second binding member 6. Furthermore, the protrusion 32 abuts against two inner surfaces 50B of the inner surfaces of the hole 50 that face each other in the second direction B. This allows the displacement of the separator 14 in the second direction B, and therefore the displacement of the electricity storage device 12, to be more restricted. Furthermore, the displacement of each separator 14 in the third direction C is permitted. Therefore, when each electricity storage device 12 repeatedly expands and contracts due to charging and discharging, etc., each separator 14 can displace in the third direction C following this expansion and contraction. This allows the separator 14 to be suppressed from being damaged or deformed.

[0048] At least one of the first restraining member 4 and the second restraining member 6 is made of a single plate material. This can suppress an increase in the number of parts of the energy storage module 1. In addition, the flatness of the main body can be increased. In addition, the restraining member is more likely to obtain higher rigidity when made of a single plate than when it is divided. In addition, the restraining member made of a single plate may restrain the end plate 16 in a state where it is arranged so as to overlap with the middle part of the end plate 16 in the second direction B. With this configuration, it is possible to further suppress the bending of the end plate 16 caused by the expansion of the energy storage device 12. Note that the energy storage module 1 of the present disclosure can simultaneously include the separator 14 having the protrusion 32 that fits into the hole 50 of the restraining member and the heat conductive member 8 that is accommodated in the same hole 50. The heat conductive member 8 can be arranged so as to fill the space partitioned by the hole 50 and the protrusion 32. With this configuration, holes 50 can be used both as space for arranging alignment structures for each of power storage devices 12 and as space for arranging a cooling structure, so that power storage module 1 can be made smaller.

[0049] (Embodiment 2) The second embodiment has a common configuration with the first embodiment, except for the shapes of the first and second restraining members 4 and 6, and the shape of the separator 14. The following description of the second embodiment will focus on the configuration that differs from the first embodiment, and the common configuration will be briefly described or omitted. FIG. 5 is a perspective view of the second restraining member 6 included in the energy storage module 1 according to the second embodiment. FIG. 6 is a perspective view showing how the separator 14 and the second restraining member 6 are fitted together. The first restraining member 4 has a similar structure to the second restraining member 6, and therefore is not shown or described here.

[0050] The second restraining member 6 has a second main body portion 44, a pair of second arm portions 46, a hole portion 50, and a plurality of cutout portions 52. The hole portion 50 extends in the third direction C and overlaps with a plurality of power storage devices 12. The second restraining member 6 of the present embodiment has three hole portions 50 arranged at a predetermined interval in the second direction B. Each hole portion 50 is configured as a through hole penetrating the second main body portion 44 in the first direction A. Note that the hole portion 50 may be configured as a recess recessed in the first direction A. Furthermore, the number of hole portions 50 is not limited, and may be one or more.

[0051] The plurality of cutouts 52 are arranged to correspond one-to-one to each separator 14. In the second restraint member 6 of the present embodiment, the cutouts 52 are arranged to correspond one-to-one to all separators 14, but this is not limiting, and the cutouts 52 may be provided for at least some of the separators 14. Each cutout 52 is provided on a surface facing the array body 2 in the band-shaped remaining portion 54 excluding the hole 50 in the second main body portion 44. Each cutout 52 is formed as a recess recessed from the surface in the first direction A. Each cutout 52 extends from one end side to the other end side of the remaining portion 54 in the second direction B. Therefore, each cutout 52 is connected to the hole 50.

[0052] Each cutout portion 52 is a groove that is long in the second direction B, and has two inner sides 52C that face each other in the third direction C. The width of each cutout portion 52 in the third direction C, i.e., the distance between the two inner sides 52C, is equal to or smaller than the size of the electricity storage device 12 in the third direction C. For example, each cutout portion 52 is arranged so as to overlap with the center of the third direction C of the main body portion 28 of each separator 14 when viewed from the first direction A. Also, for example, each cutout portion 52 is arranged so that the center of the third direction C of each cutout portion 52 overlaps with the center of the third direction C of the main body portion 28 when viewed from the first direction A.

[0053] Each separator 14 has a protrusion 32 that fits into the hole 50. The protrusion 32 abuts against two inner surfaces 50B of the inner surfaces of the hole 50 that face each other in the second direction B. Each separator 14 also has a fitting portion 56 that fits into the cutout 52. The fitting portion 56 abuts against two inner surfaces 52C of the cutout 52 that face each other in the third direction C. The dimension of the fitting portion 56 in the third direction C is approximately equal to the distance between the two inner surfaces 52C, and the fitting portion 56 inserted into the cutout 52 is sandwiched between the two inner surfaces 52C in the third direction C. The surface of the fitting portion 56 facing the first direction A abuts against the surface of the cutout 52 facing the first direction A.

[0054] The fitting portion 56 is aligned with the protrusion 32 in the second direction B and has a lower downward protrusion height than the protrusion 32, that is, is configured as a recess that is recessed toward the center of the main body portion 28 than the protrusion 32. The fitting portion 56 is fitted into the cutout portion 52 and sandwiched between the two inner sides 52C, thereby restricting the displacement of each power storage device 12 in the third direction C. Furthermore, the fitting portion 56 abuts against the surface of the cutout portion 52 facing the first direction A, thereby restricting the displacement of each power storage device 12 in the first direction A. It is sufficient that at least one of the first restraining member 4 and the second restraining member 6 has the cutout portion 52.

[0055] The power storage module 1 according to the present embodiment may have the following first to third modifications.

[0056] (Variation 1) 7 is a perspective view showing how the second restraining member 6 and the separator 14 included in the energy storage module 1 according to the first modification are fitted together. The protrusion 32 of this modification has a larger dimension in the third direction C than the fitting portion 56. Therefore, the protrusion 32 protrudes in the third direction C beyond the fitting portion 56. This increases the contact area between the protrusion 32 and the inner surface 50B when the protrusion 32 is fitted into the hole 50. As a result, it is possible to suppress rotation of each energy storage device 12 about an axis extending in the first direction A.

[0057] Furthermore, the fitting portion 56 of this modified example has a smaller dimension in the third direction C than the fitting portion 56 of the second embodiment. For example, the dimension of the fitting portion 56 in the third direction C is substantially equal to the thickness of the main body 28. Therefore, each of the cutout portions 52 is thinner than the cutout portions 52 of the second embodiment. This can increase the strength of the second restraining member 6.

[0058] (Variation 2) FIG. 8 is a perspective view of the second restraining member 6 included in the energy storage module 1 according to the second modification. FIG. 9 is a perspective view showing how the second restraining member 6 and the separator 14 are fitted together. The cutout portions 52 of this modification are provided on two inner side surfaces 50B that face each other in the second direction B of the hole portion 50. The cutout portions 52 are formed as recesses that are recessed in the second direction B from the inner side surfaces 50B. The cutout portions 52 also penetrate the remaining portion 54 in the first direction A. The fitting portion 56 protrudes in the second direction B from a side surface of the protrusion 32 facing the second direction B. The fitting portion 56 has a smaller dimension in the third direction C than the side surface. The dimension of the fitting portion 56 in the third direction C may be the same as the dimension of the side surface in the third direction C.

[0059] When the protrusion 32 is fitted into the hole 50, the side surface of the protrusion 32 facing the second direction B abuts against the inner side surface 50B of the hole 50. When the protrusion 32 is fitted into the hole 50, the fitting portion 56 is fitted into the notch 52. In this state, the fitting portion 56 is sandwiched between the two inner sides 52C of the notch 52 facing each other in the third direction C. Furthermore, the side surface of the fitting portion 56 facing the second direction B abuts against the inner side surface 52B of the notch 52 facing the second direction B. Therefore, according to this modification, the fitting portion 56 can regulate the displacement of each of the power storage devices 12 in the second direction B and the third direction C. Also, according to this modification, the hole 50 and the notch 52 can be simultaneously formed by punching the plate material constituting the second main body 44, or the like.

[0060] (Variation 3) FIG. 10 is a perspective view of the second restraining member 6 included in the energy storage module 1 according to the third modification. FIG. 11 is a perspective view showing how the second restraining member 6 and the separator 14 are fitted together. The cutout portion 52 in this modification is provided on the surface of the remaining portion 54 facing the array body 2. Each cutout portion 52 is configured as a recess recessed in the first direction A from the surface. Each cutout portion 52 is rectangular when viewed from the first direction A, and is discontinuous with the hole portion 50. The fitting portion 56 is configured as a convex portion that is aligned with the convex portion 32 and protrudes downward in the second direction B. The fitting portion 56 is rectangular when viewed from the first direction A. The protruding height of the fitting portion 56 is lower than the protruding height of the convex portion 32.

[0061] When the protrusion 32 is fitted into the hole 50, the side surface of the protrusion 32 facing the second direction B abuts against the inner surface 50B of the hole 50. When the protrusion 32 is fitted into the hole 50, the fitting portion 56 is fitted into the cutout 52. In this state, the fitting portion 56 is sandwiched between the two inner surfaces 52C of the cutout 52 facing each other in the third direction C. In addition, the fitting portion 56 is sandwiched between the two inner surfaces 52B of the cutout 52 facing each other in the second direction B. Furthermore, the surface of the fitting portion 56 facing the first direction A abuts against the surface of the cutout 52 facing the first direction A. Therefore, according to this modification, the fitting portion 56 can regulate the displacement of each of the power storage devices 12 in the first direction A, the second direction B, and the third direction C.

[0062] The above describes the embodiments of the present disclosure in detail. The above-mentioned embodiments merely show specific examples of implementing the present disclosure. The contents of the embodiments do not limit the technical scope of the present disclosure, and many design changes such as changes, additions, and deletions of components are possible within the scope of the invention defined in the claims. A new embodiment with a design change has the effects of each of the combined embodiments and modifications. In the above-mentioned embodiments, the contents for which such design changes are possible are emphasized by adding notations such as "in this embodiment" and "in this embodiment", but design changes are permitted even in contents without such notations. In addition, any combination of components included in each embodiment is also valid as an aspect of the present disclosure. The hatching on the cross section of the drawing does not limit the material of the object to which the hatching is added.

[0063] (Other variations) At least one of the first restraining member 4 and the second restraining member 6 may have a plurality of holes 50 arranged in one-to-one correspondence with the respective power storage devices 12. In other words, the restraining member may have a structure in which holes 50 that overlap with only one power storage device 12 in the first direction A are arranged in the third direction C. This can increase the strength of the restraining member compared to a case in which holes 50 extending in the third direction C are provided. The holes 50 are preferably arranged in one-to-one correspondence with all power storage devices 12, but are not limited thereto, and the holes 50 may be provided for some of the power storage devices 12. [Explanation of symbols]

[0064] REFERENCE SIGNS LIST 1 energy storage module, 2 array body, 4 first restraint member, 6 second restraint member, 8 heat conduction member, 10 cooling plate, 12 energy storage device, 14 separator, 24 output terminal, 26 valve portion, 32 protrusion portion, 50 hole portion, 52 cutout portion, 56 fitting portion.

Claims

1. an array in which a plurality of power storage devices each having a first surface and a second surface opposite to the first surface and larger in a second direction perpendicular to the first direction than in a first direction in which the first surface and the second surface are aligned are arranged in a third direction perpendicular to the first direction; a first restraining member that faces the first surface of each power storage device and extends in the third direction to restrain the array in the third direction; a second restraining member that faces the second surface of each power storage device and extends in the third direction to restrain the array in the third direction; At least one of the first restraining member and the second restraining member has a recess recessed in the first direction or a hole formed by a through hole penetrating the restraining member in the first direction, the second restraint member has the hole portion configured as a through hole, the power storage module includes a heat conductive member accommodated in the hole and in contact with the second surface so as to be capable of heat exchange; Energy storage module.

2. the power storage device has a pair of output terminals on the first surface, In the array, the power storage devices are arranged so that each first surface faces the same direction. The energy storage module according to claim 1 .

3. The power storage device has a valve portion on the first surface, the first restraint member has the hole portion configured as a through hole, The hole portion overlaps with the output terminal or the valve portion when viewed from the first direction. The power storage module according to claim 2 .

4. the power storage module includes a cooling plate on which the array is placed via the second restraint member and which is in heat exchangeable contact with the heat conductive member housed in the hole portion; The energy storage module according to claim 1 .

5. An array in which a plurality of power storage devices each having a first surface and a second surface opposite the first surface and larger in a second direction perpendicular to the first direction than in a first direction in which the first surface and the second surface are aligned are arranged in a third direction perpendicular to the first direction and the second direction; a first restraining member that faces the first surface of each power storage device and extends in the third direction to restrain the array in the third direction; a second restraining member that faces the second surface of each power storage device and extends in the third direction to restrain the array in the third direction; At least one of the first restraining member and the second restraining member has a recess recessed in the first direction or a hole formed by a through hole penetrating the restraining member in the first direction, the array includes a separator disposed between two adjacent power storage devices to provide insulation between the two power storage devices, The separator has a protrusion that fits into the hole. Energy storage module.

6. The hole portion extends in the third direction and overlaps with a plurality of the power storage devices, The protrusions abut against two inner surfaces of the inner surface of the hole that face each other in the second direction. The power storage module according to claim 5 .

7. At least one of the first restraining member and the second restraining member has a plurality of cutout portions arranged to correspond one-to-one to each separator and having two inner surfaces facing each other in the third direction, The separator has a fitting portion that abuts against the two inner surfaces of the cutout portion. The power storage module according to claim 5 or 6.

8. At least one of the first restraining member and the second restraining member has a plurality of the holes arranged so as to correspond one-to-one to each of the power storage devices. The energy storage module according to claim 1 .

9. At least one of the first restraining member and the second restraining member is formed of a single plate material. The energy storage module according to claim 1 .

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