Electricity storage device

Abstract

A power storage device includes a plurality of power storage modules stacked on each other. Each power storage module is provided with an electrode laminate and a frame. The frame body has a pair of first frame portions and a pair of second frame portions. The pair of first frame portions includes a liquid injection frame portion in which a liquid injection port is formed. At least one of the pair of second frame parts has a second frame part main body, a protrusion provided on either one of the upper surface and the lower surface of the second frame part main body, and a recess provided on the other of the upper surface and the lower surface of the second frame part main body and having a shape to fit with the protrusion. A portion of the upper surface and the lower surface of the liquid injection frame portion, which overlaps the liquid injection port in the vertical direction, is formed flat.

Description

Technical Field

[0001] The present disclosure relates to a power storage device. Background Art

[0002] Japanese Patent Application Publication No. 2005-503655 discloses a bipolar battery having multiple bipolar plate stacks. Each bipolar plate stack comprises a bipolar plate, a positive electrode disposed on one side of the bipolar plate, a cathode disposed on the other side of the bipolar plate, and a frame that supports the bipolar plate. The frame has an annular convex portion and an annular concave portion on its upper surface. In the bipolar battery, the convex portion of one bipolar plate stack fits into the concave portion of the bipolar plate stack stacked above it. Summary of the Invention

[0003] In a bipolar battery such as that described in JP-A-2005-503655, when a liquid injection port for injecting electrolyte is provided in the frame, the liquid injection port may interfere with the convex portion and / or concave portion, thus limiting the design of the liquid injection port.

[0004] An object of the present disclosure is to provide an electricity storage device capable of suppressing positional deviation between stacked electricity storage modules while ensuring the degree of freedom in designing a liquid injection port.

[0005] 14. The battery storage device of claim 13, wherein the battery storage device comprises a plurality of battery storage modules stacked on top of each other, each of the plurality of battery storage modules comprising: an electrode stack comprising a plurality of electrodes stacked on top of each other; and a frame having a shape surrounding the periphery of the electrode stack and holding an edge of the electrode stack, the frame comprising: a pair of first frame portions, the pair of first frame portions opposing each other and holding a portion of the edge of the electrode stack; and a pair of second frame portions, the pair of second frame portions extending in a direction intersecting the first frame portion and opposing each other and holding the remaining portion of the edge of the electrode stack, the pair of first frame portions comprising a liquid injection frame portion, the liquid injection frame portion having a shape A liquid injection port is formed for supplying electrolyte to the electrode stack, and at least one of the pair of second frame parts has: a second frame part main body, which connects the pair of first frame parts to each other and has an upper surface and a lower surface; at least one protrusion, which is arranged on any one of the upper surface and the lower surface of the second frame part main body; and at least one recess, which is arranged on the other of the upper surface and the lower surface of the second frame part main body and has a shape that fits with the protrusion. The liquid injection frame has an upper surface and a lower surface, and the parts of the upper surface and the lower surface of the liquid injection frame that overlap with the liquid injection port in the upper and lower directions are formed flat.

[0006] The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 This is a perspective view schematically showing a power storage device in one embodiment of the present disclosure.

[0008] Figure 2 It is a top view of the power storage device.

[0009] Figure 3 It is a cross-sectional view schematically showing a bipolar electrode.

[0010] Figure 4 It is a cross-sectional view schematically showing a monopolar electrode.

[0011] Figure 5 yes Figure 2 Cross-sectional view at line VV in FIG.

[0012] Figure 6 It is a cross-sectional view schematically showing a modified example of the arrangement of protrusions and recesses.

[0013] Figure 7 It is a cross-sectional view schematically showing a modified example of the protrusion.

[0014] Figure 8 It is a cross-sectional view schematically showing a modified example of the protrusion.

[0015] Figure 9 It is a perspective view schematically showing a modified example of the protrusion.

[0016] Figure 10 It is a cross-sectional view schematically showing a modified example of the protrusion.

[0017] Figure 11 It is a perspective view schematically showing a modified example of the power storage device.

[0018] Figure 12 It is a perspective view schematically showing a modified example of the power storage device.

[0019] Figure 13 It is a perspective view schematically showing a modified example of the power storage device. DETAILED DESCRIPTION

[0020] The embodiments of the present disclosure will be described with reference to the accompanying drawings. In the drawings referred to below, the same or corresponding components are denoted by the same reference numerals.

[0021] Figure 1This is a perspective view schematically showing a power storage device in one embodiment of the present disclosure. Figure 2 It is a top view of the power storage device.

[0022] like Figure 1 and Figure 2 As shown, the power storage device 1 includes a plurality of power storage modules 10. The plurality of power storage modules 10 are stacked one on top of another. In this embodiment, the plurality of power storage modules 10 include four power storage modules 10. However, the number of power storage modules 10 is not limited to four. Figure 2 As shown in FIG. 1 , the outer shape of each power storage module 10 in a plan view is rectangular. Each power storage module 10 includes an electrode stack 100 and a frame 200 .

[0023] The electrode stack 100 includes a plurality of electrodes stacked on top of each other. The electrode stack 100 has an edge 101. Each electrode may be Figure 3 The electrode stack 100 is constructed by alternatingly stacking bipolar electrodes 110 and separators 130. The bipolar electrode 110 includes a collector foil 111, a positive electrode active material layer 112 disposed on one side of the collector foil 111, and a negative electrode active material layer 113 disposed on the other side of the collector foil 111. In this case, the electrode stack 100 is constructed by alternatingly stacking bipolar electrodes 110 and separators 130.

[0024] Alternatively, each electrode may be formed by Figure 4 The electrode stack 100 is composed of a positive or negative monopolar electrode 120. The positive or negative monopolar electrode 120 includes a collector foil 121 and an active material layer 122 provided on the collector foil. In this case, the electrode stack 100 is composed of a positive monopolar electrode 120 and a negative monopolar electrode 120 stacked with a separator 130 interposed therebetween.

[0025] The frame 200 has a shape that surrounds the electrode stack 100. The frame 200 holds the edge 101 of the electrode stack 100. The frame 200 is formed of an insulating material (resin, etc.). The frame 200 is preferably formed of a thermoplastic resin. The frame 200 seals the edge 101 of the electrode stack 100. The frame 200 has the function of preventing the electrolyte from leaking from the electrode stack 100 and moisture from entering the electrode stack 100 from the outside, and the function of ensuring the spacing between the electrodes. The frame 200 is formed into a square cylindrical shape.

[0026] The frame body 200 includes a pair of first frame portions 210 and a pair of second frame portions 220 .

[0027] The pair of first frame portions 210 face each other. The pair of first frame portions 210 hold a portion of the edge portion 101 of the electrode stack 100. Each first frame portion 210 has a first direction (refer to Figure 1 ) is a shape that extends on the

[0028] The pair of first frames 210 includes a liquid injection frame 210A. The liquid injection frame 210A is formed with a plurality of liquid injection ports 211 for supplying electrolyte to the electrode stack 100. The plurality of liquid injection ports 211 are arranged at intervals along the first direction. Figure 1 and Figure 2 For convenience, three liquid injection ports 211 are shown, but the number of liquid injection ports 211 is not limited to 3. The liquid injection frame 210A has an upper surface and a lower surface, and the range of the upper surface and the lower surface overlapping the liquid injection ports 211 in the vertical direction is formed flat.

[0029] The liquid injection frame portion 210A may be provided with a voltage detection terminal 212. The voltage detection terminal 212 is electrically connected to the electrodes of the electrode stack 100. The voltage detection terminal 212 may be provided at an end portion of the liquid injection frame portion 210A in the first direction.

[0030] The pair of second frame portions 220 extend in a direction intersecting the first frame portion 210 and face each other. In this embodiment, each second frame portion 220 extends in a second direction orthogonal to the first frame portion 210 (see FIG. Figure 1 The length of the second frame portion 220 in the second direction is greater than the length of the first frame portion 210 in the first direction. The pair of second frame portions 220 holds the remaining portion of the edge portion 101 of the electrode stack 100 .

[0031] At least one of the pair of second frame portions 220 includes a second frame portion body 221, at least one protrusion 222, at least one recess 224, and at least one partition wall 226. In this embodiment, Figure 1 and Figure 2 As shown, each second frame portion 220 has two protrusions 222, two recesses 224, and two partition walls 226. However, the number of protrusions 222, the number of recesses 224, and the number of partition walls 226 are not limited to two.

[0032] Each second frame body 221 connects a pair of first frame parts 210 to each other. Figure 5 As shown, each second frame portion 220 has an upper surface S1 and a lower surface S2 .

[0033] The two protrusions 222 are provided at positions separated from each other in the second direction. Each protrusion 222 is provided on either the upper surface S1 or the lower surface S2 of the second frame body 221. In this embodiment, the protrusions 222 are provided on the upper surface S1 of the second frame body 221. The height of the protrusions 222 from the upper surface S1 is preferably set to be not less than 5% and not more than 75% of the height of the second frame body 221 (the dimension between the upper surface S1 and the lower surface S2).

[0034] The protrusion 222 has a shape such that the cross-sectional area of ​​the protrusion 222, as measured on a plane perpendicular to the vertical direction, gradually decreases as it moves away from the upper surface S1 of the second frame body 221. In this embodiment, the protrusion 222 has an upwardly convex curved shape. Specifically, the protrusion 222 is formed in the shape of a semicircular plate with a substantially uniform thickness in the first direction. The protrusion 222 may also be formed in a hemispherical shape.

[0035] Each recess 224 is provided at a position corresponding to each protrusion 222 in the vertical direction. Each recess 224 is provided on the other of the upper surface S1 and the lower surface S2 of the second frame body 221. In the present embodiment, the recess 224 is provided on the lower surface S2 of the second frame body 221. The recess 224 has a shape that fits with the protrusion 222. The recess 224 has a shape that is recessed upward from the lower surface S2. In the present embodiment, the recess 224 opens outward in the direction (first direction) that connects the pair of second frame portions 220 to each other.

[0036] The partition wall 226 is formed inside the recessed portion 224 in the direction connecting the pair of second frame portions 220 . The partition wall 226 partitions the electrode stack 100 from the space outside the second frame portion 220 .

[0037] like Figure 5 As shown, the partition wall 226 may also have a guide surface 226a. The guide surface 226a is formed at the lower end of the partition wall 226. The guide surface 226a guides the protrusion 222 toward the recess 224. In more detail, as shown in FIG. Figure 5 As shown by the middle arrow, when stacking other storage modules 10 on one storage module 10 , the guide surfaces 226 a of the other storage modules 10 guide the protrusions 222 of one storage module 10 toward the recesses 224 of the other storage modules 10 .

[0038] Furthermore, the partition wall 226 may be omitted from the second frame portion 220 , and the recessed portion 224 may penetrate the second frame portion main body 221 in the thickness direction (first direction).

[0039] like Figure 1 As shown, the second frame portion 220 may also have a step portion 228. The step portion 228 may protrude from the outer side surface of the second frame portion main body 221 or may be recessed from the outer side surface of the second frame portion main body 221. The step portion 228 can be used to hook the operator's finger or the hook of a crane when removing the power storage module 10.

[0040] As described above, in the energy storage device 1 of this embodiment, the protrusion 222 of the second frame portion 220 in one energy storage module 10 fits into the recess 224 of the second frame portion 220 in the adjacent energy storage module 10, thereby effectively positioning and stacking the multiple energy storage modules 10. Furthermore, unlike the first frame portion 210 in which the liquid injection port 211 is formed, the second frame portion 220 includes the protrusion 222 and the recess 224. This allows for both design freedom for the liquid injection port 211 and the protrusion 222 and recess 224.

[0041] Furthermore, adjacent storage modules 10 are positioned relative to each other by the protrusions 222 and recesses 224. Therefore, when the plurality of storage modules 10 are constrained from both sides in the stacking direction by the constraining plates, even with a relatively small restraining load (e.g., 40 kN), the positional offset between the storage modules 10 that occurs when a collision under specified conditions is input can be suppressed to less than 10 mm.

[0042] Hereinafter, modifications of the above-described embodiment will be described.

[0043] <First Modification>

[0044] like Figure 6 As shown, the recess 224 opens inward in the direction (first direction) connecting the pair of second frame portions 220. The partition wall 226 is formed outside the recess 224 in the direction connecting the pair of second frame portions 220.

[0045] <Second Modification>

[0046] like Figure 7 As shown, the protrusion 222 has a top surface 222a. The top surface 222a is inclined so as to gradually approach the upper surface S1 of the second frame body 221 as it moves inward in the direction connecting the pair of second frame portions 220 (the first direction). The recess 224 has a contact surface 224a that contacts the top surface 222a. The contact surface 224a is inclined so as to gradually approach the lower surface S2 of the second frame body 221 as it moves inward in the first direction.

[0047] <Third Modification>

[0048] like Figure 8 As shown, the top surface 222a of the protrusion 222 is inclined so as to gradually move away from the upper surface S1 of the second frame body 221 as it moves inward in the direction (first direction) connecting the pair of second frame portions 220. The contact surface 224a of the recess 224 is inclined so as to gradually move closer to the upper surface S1 of the second frame body 221 as it moves inward in the first direction.

[0049] <Fourth Modification>

[0050] like Figure 9 and Figure 10 As shown, the protrusion 222 has a base portion 222b and a tip portion 222c.

[0051] The base 222b stands upright from the upper surface S1 of the second frame body 221. The base 222b has a shape in which the cross-sectional area of ​​the base 222b at a plane perpendicular to the vertical direction is uniform in the vertical direction. Figure 9 In the example shown, the base portion 222b is formed in a cylindrical shape, but the base portion 222b may be formed in an elliptical column shape, a polygonal column shape (such as a quadrangular column shape), or the like.

[0052] The top portion 222c is provided on the base portion 222b. That is, the base portion 222b connects the upper surface S1 of the second frame body 221 and the top portion 222c. The top portion 222c has the following shape: as it moves away from the upper surface S1 of the second frame body 221, the cross-sectional area of ​​the top portion 222c at the orthogonal plane perpendicular to the up and down direction gradually decreases. Figure 9 In the above example, the tip portion 222c is formed in a truncated cone shape, but the tip portion 222c may be formed in an elliptical truncated cone shape, a truncated pyramid shape, or the like.

[0053] <Fifth Modification>

[0054] like Figure 11 As shown, the positions of the protrusions 222 and recesses 224 in each storage battery module 10 are offset relative to each other in the direction (second direction) connecting the pair of first frame portions 210. For example, the protrusion 222 in one storage battery module 10 may be provided at a position offset relative to the protrusion 222 in the adjacent storage battery module 10 in the direction (second direction) connecting the pair of first frame portions 210.

[0055] <Sixth Modification>

[0056] like Figure 12 As shown, the pair of first frame portions 210 in each battery module 10 includes an opposing frame portion 210B that faces the liquid injection frame portion 210A. The opposing frame portion 210B includes an opposing frame portion body 216 that connects the pair of second frame portions 220, at least one protrusion 217 formed on the opposing frame portion body 216, and at least one recess (not shown) formed in the opposing frame portion body 216. The shapes of the protrusion 217 and recess in the opposing frame portion 210B can be the same as or different from the shapes of the protrusion 222 and recess 224 in the second frame portion 220.

[0057] <7th Modification>

[0058] like Figure 13As shown, the liquid injection frame 210A has: a liquid injection frame body 213, at least one protrusion 214 formed on the liquid injection frame body 213, and at least one recess 215 formed on the liquid injection frame body 213. The protrusion 214 in the liquid injection frame 210A is formed in a portion of the upper surface of the liquid injection frame body 213 that does not overlap with the liquid injection ports 211 in the up-down direction. The recess 215 in the liquid injection frame 210A is formed in a portion of the lower surface of the liquid injection frame body 213 that does not overlap with the liquid injection ports 211 in the up-down direction. Figure 13 In the example shown, both the pair of first frame portions 210 have protrusions 214 and 217 and recesses. Furthermore, if at least one of the pair of first frame portions 210 has a protrusion and a recess, the protrusion 222 and recess 224 of one of the pair of second frame portions 220 may be omitted, or the protrusion 222 and recess 224 of both the pair of second frame portions 220 may be omitted.

[0059] Those skilled in the art will appreciate that the above-mentioned exemplary embodiments and examples are specific examples of the following technical solutions.

[0060] [Technical Solution 1]

[0061] An electric storage device,

[0062] The power storage device includes a plurality of power storage modules stacked on top of each other.

[0063] Each of the plurality of power storage modules includes:

[0064] an electrode stack including a plurality of electrodes stacked on each other; and

[0065] a frame having a shape surrounding the electrode stack and holding an edge of the electrode stack;

[0066] The frame has:

[0067] a pair of first frame portions, the pair of first frame portions facing each other and holding a portion of the edge portion of the electrode stack; and

[0068] a pair of second frame portions, each extending in a direction intersecting the first frame portion and facing each other, and holding the remaining portion of the edge of the electrode stack;

[0069] One of the pair of first frame portions includes a liquid injection frame portion having a liquid injection port formed therein for supplying an electrolyte solution to the electrode stack.

[0070] At least one of the pair of second frame portions has:

[0071] a second frame body connecting the pair of first frame parts to each other and having an upper surface and a lower surface;

[0072] at least one protrusion provided on either the upper surface or the lower surface of the second frame body; and

[0073] at least one recessed portion, the at least one recessed portion being provided on the other of the upper surface and the lower surface of the second frame body and having a shape that fits with the protrusion,

[0074] The liquid injection frame has an upper surface and a lower surface, and portions of the upper surface and the lower surface of the liquid injection frame that overlap with the liquid injection port in the vertical direction are formed flat.

[0075] In this energy storage device, the protrusion of the second frame portion of one energy storage module fits into the recess of the second frame portion of the adjacent energy storage module, thereby suppressing positional misalignment between stacked energy storage modules. Furthermore, the second frame portion, separate from the liquid injection frame portion having the liquid injection port, has both the protrusion and the recess, and the portions of the upper and lower surfaces of the liquid injection frame portion that vertically overlap the liquid injection port are flat. This ensures both design freedom for the liquid injection port and design freedom for the protrusion and recess.

[0076] [Technical Solution 2]

[0077] According to the power storage device described in technical solution 1,

[0078] The at least one protrusion includes a top end portion,

[0079] The tip portion has a shape in which a cross-sectional area of ​​the tip portion in a plane perpendicular to the up-down direction gradually decreases as it moves away from the one surface of the second frame portion main body.

[0080] In this aspect, it is easy to remove the storage modules stacked on one storage module from the one storage module, and thus it is easy to maintain the storage device and replace the storage modules.

[0081] [Technical Solution 3]

[0082] According to the power storage device described in technical solution 2,

[0083] The at least one protrusion further includes a base portion connecting the one surface of the second frame body to the top portion.

[0084] The base portion has a shape in which a cross-sectional area of ​​the base portion at the orthogonal plane is uniform in the vertical direction.

[0085] [Technical Solution 4]

[0086] According to the power storage device described in technical solution 2 or 3,

[0087] The top portion has a top surface,

[0088] The top surface is inclined so as to gradually move away from or approach the one surface as it moves toward the inner side in the direction connecting the pair of second frame portions to each other.

[0089] The recessed portion has a contact surface that contacts the top surface.

[0090] In this technical solution, the top surface of the top end portion of one storage module abuts the abutting surface of the recessed portion of the storage module adjacent to the one storage module, thereby effectively suppressing positional displacement of the storage module adjacent to the one storage module relative to the one storage module in the direction connecting the pair of second frame portions to each other.

[0091] [Technical Solution 5]

[0092] The power storage device according to any one of claims 1 to 4,

[0093] The recessed portion opens outward in a direction connecting the pair of second frame portions.

[0094] The second frame body includes a partition wall formed inside the recess in a direction connecting the pair of second frame portions and partitioning the electrode stack from a space outside the second frame portion.

[0095] In this aspect, both positioning of a pair of adjacent electricity storage modules and ensuring the sealing performance of the electrode stack are achieved.

[0096] [Technical Solution 6]

[0097] The power storage device according to any one of claims 1 to 5,

[0098] The protrusion of one of the plurality of storage modules is provided at a position offset from the protrusion of an adjacent storage module among the plurality of storage modules in a direction connecting the pair of first frame portions.

[0099] [Technical Solution 7]

[0100] The power storage device according to any one of claims 1 to 6,

[0101] The pair of first frame portions includes an opposing frame portion opposing the liquid injection frame portion,

[0102] The relative frame portion has:

[0103] an opposing frame body connecting the pair of second frame portions to each other and having an upper surface and a lower surface;

[0104] at least one protrusion, the at least one protrusion being provided on any one of the upper surface and the lower surface of the relative frame body; and

[0105] At least one recessed portion is provided on the other of the upper surface and the lower surface of the opposing frame body and has a shape that fits with the protrusion.

[0106] [Technical Solution 8]

[0107] The power storage device according to any one of claims 1 to 7,

[0108] The liquid injection frame has:

[0109] a liquid injection frame body, the liquid injection frame body comprising the upper surface, the lower surface, and the liquid injection port;

[0110] at least one protrusion provided on a portion of either the upper surface or the lower surface of the liquid injection frame body that does not overlap with the liquid injection port in a vertical direction; and

[0111] At least one recessed portion is provided in a portion of the other of the upper surface and the lower surface of the liquid injection frame body that does not overlap with the liquid injection port in the vertical direction and has a shape that fits with the protrusion.

[0112] [Technical Solution 9]

[0113] The power storage device according to any one of claims 1 to 8,

[0114] A height of the protrusion from the upper surface of the second frame body is set to be not less than 5% and not more than 75% of a dimension between the upper surface and the lower surface of the second frame body.

[0115] [Technical Solution 10]

[0116] The power storage device according to any one of claims 1 to 9,

[0117] The frame is formed of thermoplastic resin.

[0118] While the embodiments of the present invention have been described, the embodiments disclosed herein are to be construed as illustrative in all respects and not restrictive. The scope of the present invention is indicated by the claims, and is intended to include all modifications within the meaning and scope of the claims and equivalents thereof.

Claims

1. An electric storage device, The power storage device includes a plurality of power storage modules stacked on top of each other. Each of the plurality of power storage modules comprises: an electrode stack including a plurality of electrodes stacked on each other; and a frame having a shape surrounding the electrode stack and holding an edge of the electrode stack, The frame has: a pair of first frame portions, the pair of first frame portions facing each other and holding a portion of the edge portion of the electrode stack; and a pair of second frame portions, the pair of second frame portions respectively extending in a direction intersecting the first frame portion and facing each other, and holding the remaining portion of the edge portion of the electrode stack, The pair of first frames includes a liquid injection frame having a liquid injection port for supplying electrolyte to the electrode stack. At least one of the pair of second frame portions has: a second frame body connecting the pair of first frame parts to each other and having an upper surface and a lower surface; at least one protrusion, the at least one protrusion being provided on any one of the upper surface and the lower surface of the second frame body; and at least one recessed portion, the at least one recessed portion being provided on the other of the upper surface and the lower surface of the second frame body and having a shape that fits with the protrusion, The liquid injection frame has an upper surface and a lower surface, and portions of the upper surface and the lower surface of the liquid injection frame that overlap with the liquid injection port in a vertical direction are formed flat.

2. The power storage device according to claim 1, The at least one protrusion comprises a top end portion, The tip portion has a shape in which a cross-sectional area of ​​the tip portion on an orthogonal plane orthogonal to the up-down direction gradually decreases as it moves away from the one surface of the second frame portion main body.

3. The power storage device according to claim 2, The at least one protrusion further includes a base portion connecting the one surface of the second frame body to the top end portion, The base has a shape in which the cross-sectional area of ​​the base at the orthogonal plane is uniform in the up-down direction.

4. The power storage device according to claim 2 or 3, The top end portion has a top surface, The top surface is inclined so as to gradually move away from or approach the one surface as it moves toward the inner side in the direction connecting the pair of second frame portions to each other. The recessed portion has a contact surface that contacts the top surface.

5. The power storage device according to any one of claims 1 to 4, The recessed portion opens outward in a direction connecting the pair of second frame portions to each other. The second frame body includes a partition wall formed inside the recess in a direction connecting the pair of second frame portions to each other and partitioning the electrode stack from a space outside the second frame portion.

6. The power storage device according to any one of claims 1 to 5, The protrusion of one of the plurality of power storage modules is provided at a position offset from the protrusion of an adjacent power storage module of the plurality of power storage modules in a direction connecting the pair of first frame portions to each other.

7. The power storage device according to any one of claims 1 to 6, The pair of first frame portions includes an opposing frame portion opposing the injection frame portion, The relative frame portion has: a relative frame body, the relative frame body connecting the pair of second frame parts to each other and having an upper surface and a lower surface; at least one protrusion, the at least one protrusion being disposed on any one of the upper surface and the lower surface of the relative frame body; and At least one recessed portion is provided on the other of the upper surface and the lower surface of the opposing frame body and has a shape that fits with the protrusion.

8. The power storage device according to any one of claims 1 to 7, The liquid injection frame has: A liquid injection frame body, the liquid injection frame body comprising the upper surface, the lower surface and the liquid injection port; at least one protrusion provided at a portion of either the upper surface or the lower surface of the liquid injection frame body that does not overlap with the liquid injection port in a vertical direction; and At least one recessed portion is provided in a portion of the other of the upper surface and the lower surface of the liquid injection frame body that does not overlap with the liquid injection port in the up-down direction and has a shape that fits with the protrusion.

9. The power storage device according to any one of claims 1 to 8, A height of the protrusion from the upper surface of the second frame body is set to be not less than 5% and not more than 75% of a dimension between the upper surface and the lower surface of the second frame body.

10. The power storage device according to any one of claims 1 to 9, The frame is formed of thermoplastic resin.

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