Power storage module

Abstract

The housing of the power storage module has a plurality of first communication holes that communicate with each of the plurality of internal spaces. The pressure adjustment valve is provided with: a resin wall body (32) in which a plurality of second communication holes (33) communicating with each of the plurality of first communication holes are formed, and which faces the housing; a protrusion (34) that protrudes from a first wall surface (32a) of the wall body (32) and is formed so as to surround each of a plurality of second communication holes (33) that open in the first wall surface (32a); and a plurality of valve bodies (30) that block the plurality of second communication holes (33) from the second wall surface (32b) side of the wall body (32). A groove portion (37) is formed in a region of the first wall surface (32a) of the wall body (32) that does not overlap the plurality of valve bodies (30) when viewed from the second direction, the groove portion (37) being recessed along the valve bodies (30) in a direction away from the housing.

Description

Technical Field

[0001] The present disclosure relates to an electricity storage module. Background Art

[0002] An electricity storage module is disclosed in Patent Document 1. The electricity storage module includes: a module main body having an electrode laminate in which a plurality of bipolar electrodes are laminated and a frame configured to surround the electrode laminate and having a first communication hole communicating with an internal space of the electrode laminate; and a pressure regulating valve assembled to the module main body and having a second communication hole communicating with the first communication hole. The pressure regulating valve includes an elastic member having a sealing surface that blocks the second communication hole, and a concave portion communicating with the second communication hole is formed in the sealing surface.

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2019-192547 Summary of the Invention

[0006] Problems to be Solved by the Invention

[0007] In such a technical field, it is desired to efficiently permeate the gas generated inside a single cell to the outside of the electricity storage module without operating the pressure regulating valve. In the above-described electricity storage module, by forming a concave portion in the elastic member that functions as the valve body of the pressure regulating valve, the surface area of the space communicating with the internal space of the pressure regulating valve is increased, so that the gas permeation amount to the outside of the module via the pressure regulating valve increases when gas is generated in the internal space. However, forming a concave portion in the elastic member as in the above-described electricity storage module may impair the function of the elastic member as the valve body, which is not preferable. In addition, enlarging the pressure regulating valve itself to increase the surface area of the space on the pressure regulating valve side communicating with the internal space will decrease the energy density of the electricity storage module, which is not preferable.

[0008] An object of the present disclosure is to provide a technique that can suppress the enlargement of the electricity storage module and increase the amount of gas permeating to the outside of the electricity storage module.

[0009] Solutions for Solving the Problems

[0010] One aspect of the present disclosure relates to a power storage module including: a module main body having an electrode laminate and a housing, the electrode laminate including a plurality of electrodes laminated in a first direction, the housing being disposed to surround the electrode laminate and enclosing a plurality of internal spaces respectively formed between the plurality of electrodes adjacent to each other in the first direction; and a pressure regulating valve assembled to the housing. The housing has a plurality of first communication holes respectively communicating with the plurality of internal spaces and opening on the outer peripheral surface of the housing. The pressure regulating valve includes: a resin wall body formed with a plurality of second communication holes respectively communicating with the plurality of first communication holes and facing the housing; a protrusion protruding from a first wall surface of the wall body facing the outer peripheral surface of the housing along a second direction intersecting the first direction toward the housing and formed to surround the plurality of second communication holes opening on the first wall surface; and a plurality of valve bodies respectively closing the plurality of second communication holes from a second wall surface side opposite to the first wall surface of the wall body. A groove portion recessed in a direction away from the housing along the valve body is formed in a region of the first wall surface of the wall body that includes an opening of one of the plurality of second communication holes surrounded by the protrusion and does not overlap with the plurality of valve bodies when viewed from the second direction.

[0011] In the above power storage module, a single cell is constituted by electrodes adjacent to each other in the first direction. A part of the gas generated in the internal space of each single cell can permeate through the wall body facing the intermediate space. Since the groove portion is formed on the wall surface of the wall body, the surface area of the wall surface exposed to the intermediate space can be increased compared with the case where the wall surface is formed flat. Thus, the gas permeation path is increased, and the amount of gas permeating to the outside of the pressure regulating valve can be increased. Since such a groove portion is formed along the valve body in a region not overlapping with the valve body, the space formed by the pressure regulating valve can be effectively utilized, and the enlargement of the power storage module can be suppressed.

[0012] Alternatively, the plurality of valve bodies may be cylindrical, and when viewed from the second direction, the protrusion surrounds each of the second communication holes in a rectangular frame shape. In this configuration, since the protrusion is in a rectangular frame shape and the valve body is in a circular shape, it is easy to form a region where the valve body is not disposed in the region inside the protrusion, and it is easy to secure a space for forming the groove portion.

[0013] Alternatively, when viewed from the second direction, at least a part of the edge portion of the groove portion may be formed in a shape along the peripheral edge of the valve body. In this configuration, a permeation path connecting the groove portion and the region where the valve body is disposed can be efficiently formed.

[0014] Alternatively, a plurality of valve bodies may be arranged along a third direction intersecting the first direction and the second direction, and the positions of the valve bodies adjacent to each other in the third direction are offset from each other in the first direction. In this configuration, since the valve bodies adjacent to each other in the third direction are inclined with respect to the third direction, it is easy to create a space for forming the groove portion.

[0015] Advantages of the Invention

[0016] According to the present disclosure, it is possible to provide a technique that can suppress the enlargement of the power storage module and increase the amount of gas that penetrates to the outside of the power storage module. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a cross-sectional view of a power storage device showing an example.

[0018] Figure 2 is along Figure 1 sectional view taken along line II-II.

[0019] Figure 3 is a cross-sectional view of a power storage module showing an example.

[0020] Figure 4 is a perspective view of a power storage module showing an example.

[0021] Figure 5 is a top view of a side surface of a main body constituting a power storage module showing an example.

[0022] Figure 6 is an exploded perspective view of a part of a power storage module showing an example. s

[0023] Figure 7 is an exploded perspective view of a pressure regulating valve showing an example.

[0024] Figure 8 is a top view of a cover showing an example.

[0025] Figure 9 is a top view of a housing showing an example.

[0026] Figure 10 is a bottom view of a housing showing an example.

[0027] Figure 11 is along Figure 10 sectional view taken along line XI-XI.

[0028] Figure 12 is a bottom view of a housing of other examples.

[0029] Figure 13 is along Figure 12Cross-sectional view taken along line XIII-XIII. Detailed Description of the Embodiment

[0030] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same or equivalent elements are denoted by the same reference numerals, and redundant descriptions are omitted. In the drawings, an XYZ orthogonal coordinate system is shown as needed. The Z-axis direction is the vertical direction as an example, and the X-axis direction (the second direction and the third direction) and the Y-axis direction (the first direction) are the horizontal directions as an example.

[0031] Figure 1 and Figure 2 is a cross-sectional view showing an electric storage device including an electric storage module according to one embodiment. In Figure 1 a cross-section orthogonal to the X-axis direction is shown. In Figure 2 a cross-section taken along line II-II of Figure 1 i.e., a cross-section orthogonal to the Y-axis direction is shown. Figure 1 and Figure 2 The electric storage device 1 shown in, for example, can be used as a battery for various vehicles such as forklifts, hybrid vehicles, and electric vehicles. The electric storage device 1 includes: a module laminate 2 including a plurality of electric storage modules 4 laminated along the Z-axis direction; and a restraint member 3 that applies a restraint load to the module laminate 2 along the Z-axis direction.

[0032] The module laminate 2 includes a plurality of (here, three) electric storage modules 4 and a plurality of (here, two) conductive plates 5. The electric storage module 4 is, for example, a bipolar battery and has a rectangular shape when viewed from the Z-axis direction. An example of the electric storage module 4 has a rectangular shape with a long side and a short side when viewed from the Z-axis direction. The electric storage module 4 is, for example, a secondary battery such as a nickel-metal hydride battery, a lithium-ion battery, or a lead battery, or an electric double layer capacitor. In the following description, a nickel-metal hydride secondary battery is exemplified.

[0033] The conductive plates 5 are disposed between the electric storage modules 4 adjacent to each other along the Z-axis direction. Thus, the plurality of electric storage modules 4 are electrically connected via the conductive plates 5. For example, each electric storage module 4 has a positive terminal surface at one end surface in the Z-axis direction and a negative terminal surface at the other end surface in the Z-axis direction, and the plurality of electric storage modules 4 laminated with the conductive plates 5 interposed therebetween are connected in series. Outside the electric storage module 4 at one end in the Z-axis direction of the module laminate 2, a current collector plate 6 having a positive terminal 6a led out is disposed. The current collector plate 6 is electrically connected to the electric storage module 4. Further, outside the electric storage module 4 at the other end in the Z-axis direction of the module laminate 2, a current collector plate 7 having a negative terminal 7a led out is disposed. The current collector plate 7 is electrically connected to the electric storage module 4. Charging and discharging of the electric storage device 1 are performed by using these positive terminal 6a and negative terminal 7a.

[0034] Inside the conductive plate 5, a plurality of flow paths 5a for allowing a refrigerant such as air to flow are provided. The flow paths 5a extend, for example, in a direction (here, the X-axis direction) that intersects (is orthogonal to) the Z-axis direction and the lead-out directions of the positive terminal 6a and the negative terminal 7a respectively. In addition to the function of serving as a connection member for electrically connecting the power storage modules 4 to each other, the conductive plate 5 also functions as a heat dissipation member that dissipates the heat generated in the power storage modules 4 by allowing the refrigerant to flow through these flow paths 5a.

[0035] The restraining member 3 includes: a pair of restraining plates 8 that sandwich the module laminate 2 in the stacking direction; a plurality of fastening members 9 such as bolts for connecting them by fastening the restraining plates 8 to each other; and struts 10 that house the main body portions (for example, the shaft portions of the bolts) of the fastening members 9. The restraining plates 8 are rectangular metal plates having an area that is one size larger than the areas of the power storage module 4 and the conductive plate 5 when viewed from the first direction. When viewed from the Z-axis direction, the restraining plates 8 are rectangular with a long side and a short side. A plate-shaped insulating member F is provided on the inner side surface (the surface on the module laminate 2 side) of the restraining plate 8. That is, the current collector plate 6 or the current collector plate 7 and the insulating member F are interposed between the module laminate 2 and the restraining plate 8. Thereby, insulation is provided between the restraining plate 8 and the module laminate 2 (the current collector plates 6, 7).

[0036] At the edge of one restraining plate 8, insertion holes 8a are provided at positions that are outside the module laminate 2 when viewed from the Z-axis direction, and at the edge of the other restraining plate 8, threaded holes 8b are provided at positions opposite to the insertion holes 8a. The fastening member 9 passes through the insertion hole 8a of one restraining plate 8 toward the threaded hole 8b of the other restraining plate 8 and is screwed into the threaded hole 8b of the other restraining plate 8. Thereby, the power storage module 4 and the conductive plate 5 are clamped by the restraining plates 8 and unitized as the module laminate 2, and a restraining load is applied to the module laminate 2 along the Z-axis direction.

[0037] In this way, the fastening members 9 are arranged outside the module laminate 2, extend along the Z-axis direction, and the module laminate 2 is restrained by fastening the pair of restraining plates 8 to each other along the Z-axis direction. The struts 10 are interposed between the pair of restraining plates 8 and extend along the Z-axis direction together with the fastening members 9. The struts 10 define the distance between the pair of restraining plates 8 in the Z-axis direction, thereby defining the restraining force on the module laminate 2. In the power storage device 1, a plurality of one fastening member 9 and one strut 10 that houses the fastening member 9 are arranged along the long side of the restraining plate 8 when viewed from the Z-axis direction. In addition, the fastening members 9 and the struts 10 are opposite to each other in the direction along the short side of the restraining plate 8 when viewed from the Z-axis direction.

[0038] Next, the configuration of the power storage module 4 will be described in detail. Figure 3 It is a cross-sectional view showing the power storage module. Figure 4This is a perspective view showing an electricity storage module. The electricity storage module 4 has a structure (multi-single cell structure) in which a plurality of single cells (for example, 24 single cells) are stacked in the Z-axis direction as the stacking direction. The electricity storage module 4 includes a module main body 4A and a plurality of (here, two) pressure regulating valves 22 assembled to the module main body 4A. The module main body 4A includes an electrode laminate 11 and a frame body 25 disposed so as to surround the electrode laminate 11. The electrode laminate 11 includes a plurality of electrodes stacked along the Z-axis direction with a separator 13 interposed therebetween. The electrode laminate 11 in the illustrated example has one negative terminal electrode 18, one positive terminal electrode 19, and a plurality of bipolar electrodes 14 (intermediate electrodes) disposed between the negative terminal electrode 18 and the positive terminal electrode 19 as the plurality of electrodes. The stacking direction of the electrodes may be the same as the stacking direction of the module main body 4A.

[0039] The bipolar electrode 14 includes: an electrode plate 15 including a first surface 15a and a second surface 15b opposite to the first surface 15a; a positive electrode active material layer 16 provided on the first surface 15a; and a negative electrode active material layer 17 provided on the second surface 15b. In the electrode laminate 11, the positive electrode active material layer 16 of one bipolar electrode 14 faces the negative electrode active material layer 17 of another bipolar electrode 14 adjacent in the Z-axis direction with the separator 13 interposed therebetween. In the electrode laminate 11, the negative electrode active material layer 17 of one bipolar electrode 14 faces the positive electrode active material layer 16 of another bipolar electrode 14 adjacent in the Z-axis direction with the separator 13 interposed therebetween.

[0040] The negative terminal electrode 18 includes an electrode plate 15 and a negative electrode active material layer 17 provided on the second surface 15b of the electrode plate 15. No active material layer is provided on the first surface 15a of the electrode plate 15 of the negative terminal electrode 18. The negative terminal electrode 18 is disposed at one end in the Z-axis direction of the electrode laminate 11 such that its second surface 15b becomes the inner side (center side in the Z-axis direction) of the electrode laminate 11. The negative electrode active material layer 17 of the negative terminal electrode 18 faces the positive electrode active material layer 16 of the bipolar electrode 14 at one end in the Z-axis direction with the separator 13 interposed therebetween.

[0041] The positive terminal electrode 19 includes an electrode plate 15 and a positive electrode active material layer 16 provided on the first surface 15a of the electrode plate 15. No active material layer is provided on the second surface 15b of the electrode plate 15 of the positive terminal electrode 19. The positive terminal electrode 19 is disposed at the other end in the Z-axis direction of the electrode laminate 11 such that its first surface 15a becomes the inner side of the electrode laminate 11. The positive electrode active material layer 16 of the positive terminal electrode 19 faces the negative electrode active material layer 17 of the bipolar electrode 14 at the other end in the Z-axis direction with the separator 13 interposed therebetween.

[0042] The first surface 15a of the electrode plate 15 of the negative terminal electrode 18 is the surface facing the outside of the electrode laminate 11. On the first surface 15a of the negative terminal electrode 18, the conductive plate 5 is electrically connected via the metal plate 50. Further, the second surface 15b of the electrode plate 15 of the positive terminal electrode 19 is the surface facing the outside of the electrode laminate 11. On the second surface 15b of the positive terminal electrode 19, another conductive plate 5 is electrically connected via the metal plate 50.

[0043] The electrode plate 15 includes a metal such as nickel or a nickel-plated steel sheet. As an example, the electrode plate 15 is a rectangular metal foil including nickel. The peripheral portion 15c of the electrode plate 15 (the peripheral portions of the bipolar electrode 14, the negative terminal electrode 18, and the positive terminal electrode 19) is in a rectangular frame shape and is an area where the positive electrode active material layer 16 and the negative electrode active material layer 17 are not formed. As the positive electrode active material constituting the positive electrode active material layer 16, nickel hydroxide can be cited, for example. As the negative electrode active material constituting the negative electrode active material layer 17, a hydrogen storage alloy can be cited, for example.

[0044] The separator 13 is formed in a sheet shape, for example. As the separator 13, a porous membrane including a polyolefin resin such as polyethylene (PE) or polypropylene (PP), a woven or non-woven fabric including polypropylene, polyethylene terephthalate (PET), methyl cellulose, etc. can be cited. The separator 13 can also be a separator reinforced with a vinylidene fluoride resin compound.

[0045] The frame 25 is formed in a rectangular cylindrical shape as a whole from an insulating resin, for example. The frame 25 is provided on the electrode laminate 11 so as to surround the peripheral portion 15c of the electrode plate 15. The frame 25 has: a plurality of first sealing portions 21 that are joined to the peripheral portion 15c of the electrode plate 15; and a second sealing portion 12 that extends in the stacking direction and is joined to each first sealing portion 21. The first sealing portion 21 and the second sealing portion 12 can be formed of an insulating resin such as polypropylene (PP), polyphenylene sulfide (PPS), or modified polyphenylene ether (modified PPE), for example.

[0046] Each of the plurality of first sealing portions 21 includes a first portion 21a, a second portion 21b, and a third portion 21c. The first portion 21a is formed in a rectangular frame shape when viewed from the Z-axis direction and is joined (for example, welded) to the peripheral portion 15c of the electrode plate 15. The second portion 21b is in a rectangular frame shape when viewed from the Z-axis direction and is disposed on a part of the first portion 21a. When viewed from the Z-axis direction, the inner edge of the second portion 21b is located outside the inner edge of the first portion 21a. The peripheral portion of the separator 13 is joined (for example, welded) to the first portion 21a.

[0047] The third portion 21c is a rectangular tube extending along the Z-axis, formed by joining multiple first portions 21a and multiple second portions 21b together to form an integrated structure. The first and second portions 21a, 21b can be formed, for example, by folding a single sheet. In this case, the third portion 21c is formed, for example, by welding the folded portion of the sheet (the outer ends of the first and second portions 21a, 21b) to form a welded end.

[0048] The second sealing portion 12 is formed as a whole into a rectangular cylindrical shape by, for example, an insulating resin. The second sealing portion 12 is provided around the electrode stack 11 in a manner surrounding the electrode stack 11 when viewed from the Z-axis direction. The second sealing portion 12 is joined (for example, welded) to the first sealing portion 21 in a manner surrounding the first sealing portion 21 from the outside. The second sealing portion 12 is formed, for example, by injection molding of a resin, and extends along the entire length of the electrode stack 11 in the Z-axis direction. The second sealing portion 12 is, for example, welded to the outer surface of the first sealing portion 21 by the heat during injection molding.

[0049] The first sealing portion 21 and the second sealing portion 12 seal the spaces between the bipolar electrodes 14 adjacent to each other in the Z-axis direction, between the negative terminal electrode 18 and the bipolar electrode 14, and between the positive terminal electrode 19 and the bipolar electrode 14. Thus, airtightly separated internal spaces V are formed between the bipolar electrodes 14, between the negative terminal electrode 18 and the bipolar electrode 14, and between the positive terminal electrode 19 and the bipolar electrode 14. Specifically, the frame 25, which is arranged to surround the electrode stack 11, forms internal spaces V between a plurality of electrode plates 15 adjacent to each other in the Z-axis direction and seals each of the internal spaces V. An electrolyte (not shown), such as an alkaline solution such as an aqueous potassium hydroxide solution, is contained in the internal spaces V. At least a portion of the electrolyte can be impregnated in the separator 13, the positive active material layer 16, and the negative active material layer 17. Furthermore, an example module body 4A has 24 internal spaces V. In the following description, the internal space V formed between the positive terminal electrode 19 and the bipolar electrode 14 adjacent to the positive terminal electrode 19 is sometimes referred to as the first internal space V1, the internal space V formed between adjacent bipolar electrodes 14 is sometimes referred to as the second internal space V2, and the internal space V formed between the negative terminal electrode 18 and the bipolar electrode 14 adjacent to the negative terminal electrode 18 is sometimes referred to as the third internal space V3.

[0050] like Figures 1 to 4As shown, the second sealing portion 12 includes a pair of outer peripheral surfaces 12s along the long side of the power storage module 4 and a pair of outer peripheral surfaces 12r connecting the outer peripheral surfaces 12s to each other. The outer peripheral surfaces 12s and the outer peripheral surfaces 12r are surfaces extending in the Z-axis direction. Here, the outer peripheral surface 12s is a surface intersecting (orthogonal) with the X-axis direction, and the outer peripheral surface 12r is a surface intersecting (orthogonal) with the Y-axis direction. In addition, the length of the outer peripheral surface 12s in the Y-axis direction is longer than the length of the outer peripheral surface 12r in the X-axis direction. In the above-described conductive plate 5, the flow path 5a extends in the X-axis direction and opens at a pair of surfaces of the conductive plate 5 intersecting with the X-axis direction.

[0051] Therefore, the gaps on the outer peripheral surface 12s side of the second sealing portions 12 of adjacent power storage modules 4 are used for the introduction and discharge of the refrigerant with respect to the flow path 5a (for the refrigerant to pass through). On the other hand, the gaps on the outer peripheral surface 12r side of the second sealing portions 12 of adjacent power storage modules 4 are not used for the introduction and discharge of the refrigerant with respect to the flow path 5a. Thus, in the module laminate 2, the gaps on the outer peripheral surface 12s side of the second sealing portions 12 of adjacent power storage modules 4 are open, while the gaps on the outer peripheral surface 12r side are closed by the closure E.

[0052] Here, the power storage module 4 may also include a pair of metal plates 50. In the present embodiment, the metal plates 50 are provided at one end (the end on the negative terminal electrode 18 side) and the other end (the end on the positive terminal electrode 19 side) of the electrode laminate 11 in the Z-axis direction. One of the pair of metal plates 50 contacts the first surface 15a of the electrode plate 15 of the negative terminal electrode 18 and the conductive plate 5. The other of the pair of metal plates 50 contacts the second surface 15b of the electrode plate 15 of the positive terminal electrode 19 and another conductive plate 5. In this way, in the power storage module 4, the metal plates 50 are provided on the outer sides of the negative terminal electrode 18 and the positive terminal electrode 19. The metal plate 50 (negative terminal electrode 18) disposed at one end in the Z-axis direction constitutes the negative terminal surface of the power storage module 4. In addition, the metal plate 50 (positive terminal electrode 19) disposed at the other end in the Z-axis direction constitutes the positive terminal surface of the power storage module 4.

[0053] The peripheral portion of one of the pair of metal plates 50 is clamped between the first part 21a of the first sealing portion 21 of the electrode plate 15 of the negative terminal electrode 18 and another first part 21a provided on the opposite side of the first part 21a. The pair of first parts 21a are joined (e.g., welded) by the third part 21c and integrated. The peripheral portion of the other metal plate 50 of the pair of metal plates 50 is clamped between the first part 21a of the first sealing portion 21 of the electrode plate 15 of the positive terminal electrode 19 and another first part 21a provided on the opposite side of the first part 21a. The pair of first parts 21a are also joined (e.g., welded) by the third part 21c and integrated. The metal plate 50 is a metal foil (uncoated foil) such as the electrode plate 15 on which the active material layer is not formed.

[0054] Figure 5 One wall portion 25a of the housing 25 constituting the module main body 4A is shown. Figure 6 It is an exploded perspective view showing a part of the power storage module 4. As Figures 4 to 6 shown, a plurality (here, four) of mounting regions 24 for mounting the pressure regulating valve 22 are provided on the wall portion 25a (the outer peripheral surface 12r of the second sealing portion 12). The plurality of mounting regions 24 are separated from each other in the X-axis direction. In one example, one pressure regulating valve 22 is mounted on two adjacent mounting regions 24 in the X-axis direction.

[0055] In each mounting region 24, the housing 25 has a communication hole 24a (first communication hole) communicating with the internal space V (refer to Figure 3 ). A plurality (here, six) of communication holes 24a are provided in each mounting region 24 respectively. The communication holes 24a are arranged in three columns and two rows (three columns in the Y-axis direction and two rows in the Z-axis direction) in each mounting region 24. Therefore, the communication holes 24a are arranged in twelve columns and two rows in the wall portion 25a. Each communication hole 24a communicates with the internal space V of a different single cell and opens on the outer peripheral surface 12r.

[0056] Specifically, the mounting regions 24 provided at the left end facing the paper surface in Figure 5 respectively have communication holes 24a1 and a plurality (here, five) of communication holes 24a2. In Figure 5 , the two mounting regions 24 provided on the inner side in the X-axis direction only have a plurality (here, six) of communication holes 24a2. In ​In the [diagram], the assembly regions 24 disposed at the right end facing the paper surface respectively have communication holes 24a3 and a plurality (here, five) of communication holes 24a2. The communication hole 24a1 is in communication with the first internal space V1 on the most negative side in the stacking direction. Each communication hole 24a2 is in communication with any one of the plurality of second internal spaces V2 disposed in the middle in the stacking direction. The communication hole 24a3 is in communication with the third internal space V3 on the most positive side in the stacking direction.

[0057] Each communication hole 24a includes a through hole 21h provided in the first sealing portion 21 and a through hole 12h provided in the second sealing portion 12. The communication hole 24a functions as a liquid injection hole for injecting electrolyte into the internal space V. In addition, after the electrolyte is injected, the communication hole 24a becomes a flow path for the gas (such as hydrogen gas) generated in the internal space V to flow.

[0058] In each assembly region 24, the second sealing portion 12 has a substantially frame-shaped engaging projection 27. The projection 27 is used to join the module body 4A and the pressure regulating valve 22 by heat welding, and forms a plurality (here, six) of intermediate spaces 28 for the gas from each internal space V to flow respectively. The intermediate space 28 can form a part of the liquid injection hole or the flow path for the gas to flow. The intermediate space 28 has a rectangular shape in the cross section along the plane perpendicular to the X-axis direction. The projection 27 is formed in a lattice shape when viewed from the Y-axis direction and respectively surrounds the plurality of communication holes 24a.

[0059] In ​ , the plurality of intermediate spaces 28 in the assembly region 24 disposed at the left end facing the paper surface include an intermediate space 281 in communication with the communication hole 24a1 and an intermediate space 282 in communication with the communication hole 24a2. In ​ , the plurality of intermediate spaces 28 in the two assembly regions 24 disposed on the inner side in the X-axis direction are only composed of the intermediate space 282 in communication with the communication hole 24a2. In ​ , the plurality of intermediate spaces 28 in the assembly region 24 disposed at the right end facing the paper surface include an intermediate space 283 in communication with the communication hole 24a3 and an intermediate space 282 in communication with the communication hole 24a2.

[0060] Next, the configuration of the pressure regulating valve 22 assembled to the module body 4A will be described in detail. ​ is an exploded perspective view of the pressure regulating valve. ​ is a top view of the cover. ​ is a top view of the housing. ​ is a bottom view of the housing. ​ is along ​ sectional view taken along line XI-XI of

[0061] As ​As shown, the pressure regulating valve 22 has a housing 23 and a plurality (here, 12) of valve bodies 30. The housing 23 includes a housing body 29 and a cover 31. The housing body 29 is formed of a resin such as PP, PPS, or modified PPE, for example. The housing body 29 is formed in a substantially rectangular shape when viewed from the opposite direction in which the housing body 29 faces the cover 31. The opposite direction is the assembling direction of the pressure regulating valve 22 with respect to the outer peripheral surface 12r of the module body 4A, and is also the compression direction of the valve body 30. The pressure regulating valve 22 is assembled to the module body 4A in a direction perpendicular to the outer peripheral surface 12r. Therefore, the opposite direction between the housing body 29 and the cover 31 coincides with the Y-axis direction.

[0062] The housing body 29 has a bottom wall 32 (wall body). The bottom wall 32 faces the outer peripheral surface 12r of the module body 4A in the Y-axis direction. A plurality (here, 12) of through holes 33 (second communication holes) that penetrate the bottom wall 32 in the Y-axis direction are provided in the bottom wall 32. The through holes 33 extend from the outer wall surface 32a facing the module body 4A to the inner wall surface 32b facing the cover 31.

[0063] As ​ and ​ shown, the housing body 29 has an outer peripheral wall 36 that protrudes from the bottom wall 32 toward the cover 31 side. In the present embodiment, the outer peripheral wall 36 is integrally formed with the bottom wall 32. The outer peripheral wall 36 is erected at the edge of the inner wall surface 32b of the bottom wall 32 so as to surround a plurality (here, 12) of valve bodies 30 together. Specifically, the outer peripheral wall 36 is formed on the entire circumference of the outer peripheral edge of the bottom wall 32 and constitutes the outer wall of the housing body 29. More specifically, when viewed from the Y-axis direction, the outer peripheral wall 36 is formed in a substantially rectangular frame shape along the outer peripheral edge of the bottom wall 32 formed in a substantially rectangular shape.

[0064] In one example, a cylindrical accommodation space S1 for accommodating each valve body 30 is formed in the inner wall surface 32b. The accommodation space S1 has an axis along the Y-axis direction and is formed in a concave shape from the inner wall surface 32b toward the outer wall surface 32a.

[0065] In the present embodiment, in a state where the cover 31 is fixed to the housing body 29, the cover 31 is in contact with the end surface 36a of the outer peripheral wall 36. On the other hand, the cover 31 and the inner wall surface 32b are separated from each other. That is, a space S2 is formed between the cover 31 and the inner wall surface 32b. This space S2 functions as a flow path for gas or electrolyte flowing from the internal space V into the interior of the pressure regulating valve 22.

[0066] The valve body 30 is received in the accommodation space S1 within the housing 23 in a manner that blocks the through-hole 33. A plurality of valve bodies 30 are arranged and disposed in the X-axis direction in a manner that blocks the corresponding through-holes 33. The valve body 30 is a cylindrical member formed of an elastic member such as rubber. The valve body 30 has a first end face 30a that blocks the through-hole 33 from the inner wall face 32b side of the bottom wall 32, a second end face 30b located on the side opposite to the first end face 30a, and a side face 30c that connects the first end face 30a and the second end face 30b. The second end face 30b is a pressed surface pressed by the cover 31.

[0067] The valve body 30 blocks the through-hole 33 by being disposed in a state where the first end face 30a is pressed against the accommodation space S1. The valve body 30 opens and closes the through-hole 33 according to the pressure in the internal space V. A gap G is provided between the side face 30c of the valve body 30 and the inner wall face S1a of the accommodation space S1.

[0068] As ​ and ​ shown, a protrusion 38 for positioning the valve body 30 is formed on the inner wall face S1a of the accommodation space S1. The protrusion 38 protrudes inward from the inner wall face S1a of the accommodation space S1. The protrusion 38 is provided integrally on the inner wall face S1a of the accommodation space S1 along the extending direction (Y-axis direction) of the central axis of the through-hole 33. The protrusion 38 is formed in a manner that contacts the side face 30c of the valve body 30. By bringing the protrusion 38 into contact with the valve body 30, the central position of the valve body 30 can be made to coincide with the central axis of the through-hole 33. Through such a protrusion 38, the misalignment of the valve body 30 can be suppressed within a certain range. In the present embodiment, a plurality of (here, six) protrusions 38 are formed at equal intervals around the central axis of the through-hole 33.

[0069] As ​ and ​ shown, a sealing portion 39 is formed on the bottom surface S1b of the accommodation space S1 as a protrusion that protrudes outward from the inner wall face 32b. The sealing portion 39 opens and closes the space between the through-hole 33 and the gap G by contacting the first end face 30a of the valve body 30 pressed against the sealing portion 39. The sealing portion 39 is formed in a manner that surrounds the open end of the through-hole 33 in the bottom surface S1b. The sealing portion 39 is formed in a circular ring shape centered on the central axis of the through-hole 33 along the edge portion of the through-hole 33. The sealing portion 39 is formed in a manner that surrounds the entire circumference of the through-hole 33 without a gap. Thereby, the sealing portion 39 contacts the first end face 30a of the valve body 30 without a gap, ensuring airtightness.

[0070] As ​As shown, a pair of engaging projections 34 in a substantially frame shape are provided on the outer wall surface 32a of the bottom wall 32. The pair of projections 34 are formed separately in the X-axis direction at intervals corresponding to the projections 27. The pair of projections 34 engage the module body 4A with the pressure regulating valve 22, and form a plurality (here, 12) of intermediate spaces 35 through which gases or electrolytes from the respective internal spaces V flow respectively. The projection 34 engages with the projection 27 of the module body 4A. The projection 34 has a shape and size corresponding to the projection 27. That is, when viewed from the Y-axis direction, the projection 34 is formed in a lattice shape and respectively surrounds a plurality of through holes 33.

[0071] The module body 4A and the pressure regulating valve 22 are joined by, for example, hot plate welding. Specifically, a hot plate is disposed between the module body 4A and the pressure regulating valve 22, and the tips of the projections 27 and 34 are brought into contact with the hot plate. Thereby, the tips of the projections 27 and 34 are melted. Next, during the melting of the projections 27 and 34, the tip of the projection 34 is pressed against the tip of the projection 27, thereby welding (joining) the projection 27 and the projection 34. As a result, the module body 4A and the pressure regulating valve 22 are joined. By melting the projections 27 and 34 with each other, the intermediate space 28 and the intermediate space 35 disposed at corresponding positions when viewed from the Y-axis direction are connected. In a state where the projections 27 and 34 are welded to each other, each through hole 33 is connected to each communication hole 24a of the module body 4A. In other words, the intermediate spaces 28 and 35 mediate the corresponding communication holes 24a and through holes 33.

[0072] The intermediate space 35 can be classified into an intermediate space 351 (first intermediate space) and an intermediate space 352 (second intermediate space). The intermediate space 351 is disposed in the lower row at the right end when viewed from the paper surface of the front view ​ In the case where the pressure regulating valve 22 is joined to the two fitting regions 24 on the left side of the paper surface of ​ the intermediate space 351 is connected to the intermediate space 281 communicating with the communication hole 24a1. In the case where the pressure regulating valve 22 is joined to the two fitting regions 24 on the right side of the paper surface of ​ the upper and lower portions of the pressure regulating valve 22 are reversed, so that the intermediate space 351 is connected to the intermediate space 283 communicating with the communication hole 24a3. The intermediate space 352 is connected to the intermediate space 282 communicating with the communication hole 24a2.

[0073] As ​As shown, the cover 31 is a member that closes the opening of the housing 29. The cover 31 has a side wall 40. The side wall 40 faces the bottom wall 32 of the housing 29 in the Y-axis direction with a plurality of valve bodies 30 interposed therebetween. The side wall 40 and the bottom wall 32 constitute a pair of walls of the outer shell 23 that face each other in the Y-axis direction. The cover 31 is formed of a resin such as PP, PPS, or modified PPE, for example. In one example, the cover 31 can be manufactured by injection molding. When viewed from the Y-axis direction, the position of the outer peripheral edge portion of the cover 31 substantially coincides with the position of the outer peripheral edge portion of the housing 29 (the outer edge portion of the outer peripheral wall 36).

[0074] The cover 31 is joined to the opening end surface of the housing 29 by welding such as ultrasonic welding, for example. Specifically, the outer peripheral edge portion of the side wall 40 is welded to the end surface 36a of the outer peripheral wall 36 of the housing 29. In the side wall 40, a first hole 41 and a second hole 42 that penetrate the side wall 40 in the Y-axis direction are provided. The second hole 42 is located vertically above the first hole 41. When viewed from the Y-axis direction, the first hole 41 and the second hole 42 are arranged so as not to overlap with the valve body 30. When viewed from the Y-axis direction, the first hole 41 and the second hole 42 are arranged adjacent to the valve body 30 in the Z-axis direction. The first hole 41 and the second hole 42 are arranged so as not to overlap with each other in the Z-axis direction. When viewed from the Z-axis direction, the first hole 41 and the second hole 42 are arranged separately from each other in the X-axis direction so as not to overlap.

[0075] The first hole 41 and the second hole 42 can function as an exhaust port for exhausting (discharging) the gas inside the pressure regulating valve 22 to the outside of the pressure regulating valve 22, or as a discharge port for discharging the electrolyte inside the pressure regulating valve 22 to the outside of the pressure regulating valve 22. As an example, the first hole 41 and the second hole 42 have an oval shape with the X-axis direction as the long side direction in a cross section orthogonal to the Y-axis direction. The first hole 41 and the second hole 42 have the same shape as each other.

[0076] A plurality of (six in this case) first holes 41 and a plurality of (six in this case) second holes 42 are provided in the side wall 40. The plurality of first holes 41 are arranged in a row in the X-axis direction. The plurality of second holes 42 are arranged in a row in the X-axis direction. The plurality of first holes 41 and the plurality of second holes 42 are arranged alternately in the X-axis direction. Three first holes 41 and three second holes 42 are provided for each assembly area 24.

[0077] A further description of the configuration of the housing 29 will be given. As ​ and ​As shown, the multiple through-holes 33 formed in the housing 29 include a through-hole 331 and a through-hole 332. When viewed in the Y-axis direction, the through-hole 331 corresponds to the position where the communication hole 24a1 is formed, and is communicated with the communication hole 24a1 via the intermediate space 351 and the intermediate space 281. When viewed in the Y-axis direction, the through-hole 332 corresponds to the position where the communication hole 24a2 is formed, and is communicated with the communication hole 24a2 via the intermediate space 352 and the intermediate space 282.

[0078] As ​ and ​ shown, the bottom wall 32 includes: a first wall portion 321 having an outer wall surface 32a1 facing the intermediate space 351 and facing the frame body 25 face to face; and a plurality of second wall portions 322 having an outer wall surface 32a2 facing the intermediate space 352 and facing the frame body 25 face to face. The outer wall surface 32a1 of the first wall portion 321 and the outer wall surface 32a2 of the second wall portion 322 are separated from each other by the protrusion 34. In addition, the outer wall surfaces 32a2 of the plurality of second wall portions 322 are also separated from each other by the protrusion 34.

[0079] Grooves 37 are formed in the outer wall surfaces 32a1 and 32a2 and are recessed in a direction away from the frame body 25. The grooves 37 extend along the axial direction (Y-axis direction) of the valve body 30 (accommodation space S1). When viewed in the Y-axis direction, the grooves 37 are formed so as to avoid the valve body 30 and do not overlap with the valve body 30. The grooves 37 have: an inner peripheral surface 37a that extends in a direction away from the frame body 25 along the Y-axis direction and toward the cover 31; and a bottom surface 37b that is formed at the end on the cover 31 side of the inner peripheral surface 37a. The bottom surface 37b faces the frame body 25 in the same manner as the outer wall surface 32a. The grooves 37 are formed such that the groove width becomes narrower as the distance from the frame body 25 increases, and the inner peripheral surface 37a extends obliquely with respect to the Y-axis direction. The wall surface 37a1 of the inner peripheral surface 37a of the groove 37 that is adjacent to the valve body 30 is formed by the wall portion forming the accommodation space S1. That is, on the opposite side of the wall surface 37a1 of the inner peripheral surface 37a that is adjacent to the valve body 30, there is an inner wall surface S1a of the accommodation space S1. In other words, the wall surface 37a1 is one surface of the wall portion forming the accommodation space S1, and the inner wall surface S1a is another surface of the wall portion forming the accommodation space S1.

[0080] In addition, the wall surface 37a2 of the other part of the inner peripheral surface 37a of the groove 37 that is not adjacent to the valve body 30 is formed by the outer peripheral wall 36. The bottom surface 37b is located on the opposite side of the inner wall surface 32b forming the space S2 in the bottom wall 32. For example, when viewed in the Y-axis direction, at least a part of the edge of the groove 37 may be formed along the peripheral edge of the valve body 30. That is, the wall surface 37a1 of the inner peripheral surface 37a of the groove 37 that is adjacent to the valve body 30 may be bent in a manner following the outer peripheral surface of the cylindrical valve body 30.

[0081] As ​ shown, in one example, the protrusions 34 are formed in a lattice pattern so as to surround the respective through-holes 33. Further, adjacent through-holes 33 arranged along the X-axis direction are offset from each other in the Z-axis direction. In the illustrated example, the accommodation spaces S1 of the valve bodies 30 adjacent to each other in the X-axis direction are offset from each other within a range where they overlap each other in the Z-axis direction. Therefore, when viewed from the Y-axis direction, the edge portion of the groove portion 37 is formed along a part of the circumferences of two valve bodies 30 adjacent to each other in the X-direction and a part of the protrusions 34.

[0082] As described above, the power storage module 4 of one example includes two pressure regulating valves 22 (first pressure regulating valve 22A, second pressure regulating valve 22B) having the same shape (structure) (see ​ ). In ​ the example, the first pressure regulating valve 22A is arranged near the front (left side) of the paper surface, and the second pressure regulating valve 22B is arranged far behind (right side) of the paper surface.

[0083] The first pressure regulating valve 22A and the second pressure regulating valve 22B assembled to one module body 4A are assembled to the housing 25 in a state where they are inverted with respect to each other about a rotation axis along the Y-axis direction. That is, the first pressure regulating valve 22A and the second pressure regulating valve 22B are upside down. In the first pressure regulating valve 22A, the through-hole 331 is communicated to the communication hole 24a1 communicating with the first internal space V1 via the intermediate space 351 and the intermediate space 281. In the second pressure regulating valve 22B, the through-hole 331 is communicated to the communication hole 24a3 communicating with the third internal space V3 via the intermediate space 351 and the intermediate space 283.

[0084] As described above, the power storage module 4 includes: a module main body 4A having an electrode laminate 11 and a casing 25, the electrode laminate 11 including a plurality of electrodes (bipolar electrodes 14, negative terminal electrodes 18, and positive terminal electrodes 19) laminated in the Z-axis direction, and the casing 25 being disposed so as to surround the electrode laminate 11 and enclosing a plurality of internal spaces V respectively formed between the plurality of electrodes adjacent in the Z-axis direction; and a pressure regulating valve 22 attached to the casing 25. The casing 25 has a plurality of communication holes 24a that communicate with the plurality of internal spaces V respectively and open to the outer peripheral surface 12r of the casing 25. The pressure regulating valve 22 includes: a resin bottom wall 32 formed with a plurality of through holes 33 that communicate with the plurality of communication holes 24a respectively and opposed to the casing 25; a protrusion 34 protruding from an outer wall surface 32a (first wall surface) of the bottom wall 32 opposed to the outer peripheral surface 12r of the casing 25 along a Y-axis direction intersecting the Z-axis direction toward the casing 25 and formed so as to surround the plurality of through holes 33 opening to the outer wall surface 32a respectively; and a plurality of valve bodies 30 respectively closing the plurality of through holes 33 from an inner wall surface 32b (second wall surface) side of the bottom wall 32 opposite to the outer wall surface 32a. A groove portion 37 recessed in a direction away from the casing 25 along the valve bodies 30 is formed in a region of the outer wall surface 32a of the bottom wall 32 that does not overlap with the plurality of valve bodies 30 when viewed from the Y-axis direction and includes an opening of one of the plurality of through holes 33 surrounded by the protrusion 34.

[0085] In the above-described power storage module 4, single cells are formed by electrodes adjacent to each other in the Z-axis direction. A part of the gas generated in the internal space V of each single cell can permeate through the bottom wall 32 facing the intermediate space 35. Since the groove portion 37 is formed in the outer wall surface 32a of the bottom wall 32, the surface area of the outer wall surface 32a exposed to the intermediate space 35 can be increased as compared with the case where the outer wall surface 32a is formed flat. As a result, the gas permeation path is increased, and thus the amount of gas permeating to the outside of the pressure regulating valve 22 can be increased. Since such a groove portion 37 is formed along the valve bodies 30 in a region not overlapping with the valve bodies 30, the space formed by the pressure regulating valve 22 can be effectively utilized, and the pressure regulating valve 22 can be prevented from becoming large-sized. As a result, the power storage module 4 can be prevented from becoming large-sized.

[0086] Alternatively, the plurality of valve bodies 30 may be cylindrical, and when viewed from the Y-axis direction, the protrusion 34 surrounds each of the through holes 33 in a rectangular frame shape. In this configuration, since the protrusion 34 is in a rectangular frame shape and the valve bodies 30 are circular, a region where the valve bodies 30 are not disposed is easily formed in the region inside the protrusion 34, and a space for forming the groove portion 37 can be easily ensured.

[0087] Alternatively, when viewed from the Y-axis direction, at least a part of the edge portion of the groove portion 37 is formed in a shape along the peripheral edge of the valve body 30. In this configuration, a through-path that connects the groove portion 37 and the region where the valve body 30 is disposed can be efficiently formed.

[0088] Alternatively, a plurality of valve bodies 30 are arranged along the X-axis direction that intersects the Z-axis direction and the Y-axis direction, and the positions of the valve bodies 30 adjacent to each other in the X-axis direction are offset from each other in the Z-axis direction. In this configuration, since the valve bodies 30 adjacent to each other in the X-axis direction are inclined with respect to the X-axis direction, a space for forming the groove portion 37 is likely to be generated.

[0089] As described above, an example of the present disclosure has been described in detail, but the present disclosure is not limited to the above-described manner.

[0090] For example, ​ is a bottom view of a housing according to another example, ​ is along ​ sectional view taken along line XIII-XIII. In ​ and ​ In the housing shown, the groove portion 37 is formed only on the outer wall surface 32a2 facing the intermediate space 352, and the groove portion 37 is not formed on the outer wall surface 32a1 facing the intermediate space 351. In addition, the first wall portion 321 corresponding to the outer wall surface 32a1 is formed to have a thickness substantially the same as the thickness from the bottom surface S1b of the storage space S1 to the outer wall surface 32a.

[0091] The above-described power storage module 4 includes: an outermost single cell having a first internal space V1 (or a third internal space V3); and an intermediate single cell having a second internal space V2. Gas generated inside the single cell can permeate to the outside through the frame body 25 that closes the peripheral edge of the electrode laminate 11. In the intermediate single cell located in the middle in the stacking direction, the gas easily permeates the frame body 25 in a manner along a substantially horizontal direction (X-axis direction and Y-axis direction). On the other hand, in the outermost single cell located on the outermost side in the stacking direction, in addition to the horizontal direction, the gas can also permeate the frame body 25 in a manner along the vertical direction (Z-axis direction). Therefore, the amount of gas permeating from the outermost single cell tends to be larger than the amount of gas permeating from the intermediate single cell.

[0092] In the power storage module 4, the first internal space V1 communicates with the intermediate space 351 through the communication hole 24a1, and the second internal space V2 communicates with the intermediate space 352 through the communication hole 24a2. Therefore, a part of the gas generated in the first internal space V1 that constitutes the outermost single cell can permeate through the first wall portion 321 facing the intermediate space 351. Similarly, a part of the gas generated in the second internal space V2 that constitutes the intermediate single cell can permeate through the second wall portion 322 facing the intermediate space 352.

[0093] In ​ and ​ In the housing shown, since the surface area of the outer wall surface 32a1 of the first wall portion 321 is formed to be smaller than the surface area of the outer wall surface 32a2 of the second wall portion 322, the amount of gas passing through the first wall portion 321 is less than the amount of gas passing through the second wall portion 322. Therefore, the difference between the gas permeation amount of the outermost single cell and the gas permeation amount of the intermediate single cell can be reduced.

[0094] The gist of the present disclosure can be described as follows.

[0095] [1] A power storage module, comprising:

[0096] A module main body having an electrode laminate and a casing, the electrode laminate including a plurality of electrodes laminated in a first direction, the casing being disposed so as to surround the electrode laminate and enclosing a plurality of internal spaces respectively formed between the plurality of electrodes adjacent to each other in the first direction; and

[0097] A pressure regulating valve assembled to the casing,

[0098] In the power storage module,

[0099] The casing has a plurality of first communication holes respectively communicating with the plurality of internal spaces and opening on the outer peripheral surface of the casing,

[0100] The pressure regulating valve has:

[0101] A resin wall body formed with a plurality of second communication holes respectively communicating with the plurality of first communication holes and facing the casing;

[0102] Protrusions protruding from a first wall surface of the wall body facing the outer peripheral surface of the casing along a second direction intersecting the first direction so as to go from the wall body to the casing, and formed so as to respectively surround the plurality of second communication holes opening on the first wall surface; and

[0103] A plurality of valve bodies respectively closing the plurality of second communication holes from a second wall surface side opposite to the first wall surface of the wall body,

[0104] In a region of the first wall surface of the wall body that includes an opening of one of the plurality of second communication holes surrounded by the protrusions and does not overlap with the plurality of valve bodies when viewed from the second direction, a groove portion is formed along the valve body and recessed in a direction away from the casing.

[0105] [2] The power storage module according to [1], wherein

[0106] The plurality of valve bodies are cylindrical,

[0107] When viewed from the second direction, the protrusion surrounds each of the second communication holes in a rectangular frame shape.

[0108] [3] The power storage module according to [1] or [2], wherein,

[0109] When viewed from the second direction, at least a part of the edge portion of the groove portion is formed in a shape along the peripheral edge of the valve body.

[0110] [4] The power storage module according to any one of [1] to [3], wherein,

[0111] The plurality of valve bodies are arranged along a third direction intersecting the first direction and the second direction,

[0112] The positions of the valve bodies adjacent to each other in the third direction are offset from each other in the first direction.

[0113] ​

[0114] 4 Power storage module

[0115] 4A Module body

[0116] 11 Electrode laminate

[0117] 14 Bipolar electrode (electrode)

[0118] 18 Negative terminal electrode (electrode)

[0119] 19 Positive terminal electrode (electrode)

[0120] 22 Pressure regulating valve

[0121] 24a Communication hole (first communication hole)

[0122] 25 Housing

[0123] 30 Valve body

[0124] 32 Bottom wall (wall body)

[0125] 32a Outer wall surface (first wall surface)

[0126] 33 Through hole (second communication hole)

[0127] 37 Groove portion [[ID=6,5]]

[0128] V Internal space.

Claims

1. A power storage module, comprising: A module main body having an electrode laminate and a casing, the electrode laminate including a plurality of electrodes laminated in a first direction, and the casing being arranged to surround the electrode laminate and enclosing a plurality of internal spaces respectively formed between the plurality of electrodes adjacent to each other in the first direction; and A pressure regulating valve assembled to the casing, The power storage module is characterized in that The casing has a plurality of first communication holes respectively communicating with the plurality of internal spaces and opening on the outer peripheral surface of the casing, The pressure regulating valve has: A resin wall body formed with a plurality of second communication holes respectively communicating with the plurality of first communication holes and opposing the casing; Protrusions protruding from a first wall surface of the wall body opposite to the outer peripheral surface of the casing along a second direction intersecting the first direction toward the casing and formed to surround the plurality of second communication holes opening on the first wall surface respectively; and A plurality of valve bodies respectively blocking the plurality of second communication holes from a second wall surface side of the wall body opposite to the first wall surface, In a region of the first wall surface of the wall body that includes an opening of one of the plurality of second communication holes surrounded by the protrusions and does not overlap with the plurality of valve bodies when viewed from the second direction, a groove portion is formed along the valve body and recessed in a direction away from the casing.

2. The power storage module according to claim 1, wherein The plurality of valve bodies are cylindrical, When viewed from the second direction, the protrusions surround each of the second communication holes in a rectangular frame shape.

3. The power storage module according to claim 1, wherein When viewed from the second direction, at least a part of the edge of the groove portion is formed in a shape along the circumference of the valve body.

4. The power storage module according to any one of claims 1 to 3, wherein The plurality of valve bodies are arranged along a third direction intersecting the first direction and the second direction, Positions of the valve bodies adjacent to each other in the third direction are offset from each other in the first direction.

Images