Power storage device

Abstract

To provide a power storage device capable of suppressing misalignment between stacked power storage modules while ensuring design flexibility of a liquid injection port.SOLUTION: A power storage device 1 comprises a plurality of power storage modules 10 stacked one on top of another. Each power storage module 10 includes an electrode laminate 100 and a frame 200. The frame 200 includes a pair of first frame portions 210 and a pair of second frame portions 220. The pair of first frame portions 210 includes a frame section 210A for liquid injection having a liquid injection port 211 formed. At least one of the pair of second frame portions 220 includes a second frame main body 221, a protrusion 222 provided on one of the upper surface and the lower surface of the second frame main body 221, and a recess 224 provided on the other of the upper surface and the lower surface of the second frame main body 221 and shaped to fit the protrusion 222. A region of the upper surface and the lower surface of the frame section 210A for liquid injection that overlaps with the liquid injection port 211 in a vertical direction is formed flat.SELECTED DRAWING: Figure 1

Description

Technical Field

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

Background Art

[0002] Japanese Patent Publication No. 2018-534028 discloses a bipolar battery having a plurality of bipolar plate laminates. Each bipolar plate laminate has a bipolar plate, a positive electrode provided on one surface of the bipolar plate, a negative electrode provided on the other surface of the bipolar plate, and a frame that holds the periphery of the bipolar plate. On the upper surface of the frame, an annular convex portion and an annular concave portion are provided. In the bipolar battery, the convex portion in one bipolar plate laminate is fitted into the concave portion in the bipolar plate laminate laminated on the one bipolar plate laminate.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the bipolar battery described in Japanese Patent Publication No. 2018-534028, when a liquid injection port for injecting an electrolyte is provided in the frame, there is a concern that the liquid injection port may interfere with the convex portion or the concave portion, so there are limitations in the design of the liquid injection port.

[0005] An object of the present disclosure is to provide a power storage device capable of suppressing displacement between power storage modules laminated on each other while ensuring a degree of freedom in the design of a liquid injection port.

Means for Solving the Problems

[0006] A power storage device according to one aspect of the present disclosure includes a plurality of power storage modules stacked on one another. Each of the plurality of power storage modules includes an electrode laminate including a plurality of electrodes stacked on one another, and a frame body having a shape surrounding the periphery of the electrode laminate and holding an edge portion of the electrode laminate. The frame body includes a pair of first frame portions facing each other and holding a part of the edge portion of the electrode laminate, and a pair of second frame portions extending in a direction intersecting the first frame portions and facing each other and holding the remaining part of the edge portion of the electrode laminate. The pair of first frame portions includes a liquid injection frame portion in which a liquid injection port for supplying an electrolytic solution to the electrode laminate is formed. At least one of the pair of second frame portions connects the pair of first frame portions to each other, and includes a second frame portion main body having an upper surface and a lower surface, at least one protrusion provided on one of the upper surface and the lower surface of the second frame portion main body, and at least one recess provided on the other surface of the upper surface and the lower surface of the second frame portion main body and having a shape fitting with the protrusion. The liquid injection frame portion has an upper surface and a lower surface, and a portion overlapping the liquid injection port in the vertical direction of the upper surface and the lower surface is formed flat. Power storage device.

Effect of the Invention

[0007] According to the present disclosure, it is possible to provide a power storage device capable of suppressing displacement between power storage modules stacked on one another while ensuring a degree of freedom in the design of the liquid injection port.

Brief Description of the Drawings

[0008]

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Mode for Carrying Out the Invention

[0009] Embodiments of the present disclosure will be described with reference to the drawings. In the drawings referred to below, the same or corresponding members are denoted by the same reference numerals.

[0010] FIG. 1 is a perspective view schematically showing an electrical storage device according to an embodiment of the present disclosure. FIG. 2 is a plan view of the electrical storage device.

[0011] As shown in FIGS. 1 and 2, the electrical storage device 1 includes a plurality of electrical storage modules 10. The plurality of electrical storage modules 10 are stacked on one another. In the present embodiment, the plurality of electrical storage modules 10 include four electrical storage modules 10. However, the number of electrical storage modules 10 is not limited to four. As shown in FIG. 2, the outer shape of each electrical storage module 10 in plan view is formed in a rectangular shape. Each electrical storage module 10 includes an electrode laminate 100 and a frame body 200.

[0012] The electrode laminate 100 includes a plurality of electrodes laminated on each other. The electrode laminate 100 has an edge portion 101. Each electrode may be constituted by the bipolar electrode 110 shown in FIG. 3. The bipolar electrode 110 has a current collector foil 111, a positive electrode active material layer 112 provided on one surface of the current collector foil 111, and a negative electrode active material layer 113 provided on the other surface of the current collector foil 111. In this case, the electrode laminate 100 is constituted by alternately laminating the bipolar electrode 110 and the separator 130.

[0013] Alternatively, each electrode may be constituted by the monopolar electrode 120 shown in FIG. 4. The monopolar electrode 120 of the positive electrode or the negative electrode has a current collector foil 121 and an active material layer 122 provided on the current collector foil. In this case, the electrode laminate 100 is constituted by laminating the monopolar electrode 120 of the positive electrode and the monopolar electrode 120 of the negative electrode with the separator 130 interposed therebetween.

[0014] The frame body 200 has a shape surrounding the periphery of the electrode laminate 100. The frame body 200 holds the edge portion 101 of the electrode laminate 100. The frame body 200 is made of an insulating material (such as resin). Preferably, the frame body 200 is made of a thermoplastic resin. The frame body 200 seals the edge portion 101 of the electrode laminate 100. The frame body 200 has a function of preventing leakage of the electrolytic solution from the electrode laminate 100 and intrusion of moisture from the outside into the electrode laminate 100, and a function of ensuring the interval between each electrode. The frame body 200 is formed in a rectangular tube shape.

[0015] The frame body 200 has a pair of first frame portions 210 and a pair of second frame portions 220.

[0016] The pair of first frame portions 210 face each other. The pair of first frame portions 210 hold a part of the edge portion 101 of the electrode laminate 100. Each first frame portion 210 has a shape extending in the first direction (see FIG. 1).

[0017] The pair of first frame parts 210 includes a liquid injection frame part 210A. A plurality of liquid injection ports 211 for supplying an electrolytic solution to the electrode laminate 100 are formed in the liquid injection frame part 210A. The plurality of liquid injection ports 211 are provided at intervals along the first direction. In FIGS. 1 and 2, for convenience, three liquid injection ports 211 are shown, but the number of liquid injection ports 211 is not limited to three. The liquid injection frame part 210A has an upper surface and a lower surface, and the ranges of the upper surface and the lower surface that overlap the liquid injection ports 211 in the vertical direction are formed flat.

[0018] A voltage detection terminal 212 may be provided in the liquid injection frame part 210A. The voltage detection terminal 212 is electrically connected to the electrodes of the electrode laminate 100. The voltage detection terminal 212 may be provided at an end of the liquid injection frame part 210A in the first direction.

[0019] The pair of second frame parts 220 each extend in a direction intersecting the first frame part 210 and face each other. In the present embodiment, each second frame part 220 extends in a second direction (see FIG. 1) orthogonal to the first frame part 210. The length of the second frame part 220 in the second direction is greater than the length of the first frame part 210 in the first direction. The pair of second frame parts 220 hold the remaining part of the edge 101 of the electrode laminate 100.

[0020] At least one of the pair of second frame parts 220 has a second frame part main body 221, at least one protrusion 222, at least one recess 224, and at least one blocking wall 226. In the present embodiment, as shown in FIGS. 1 and 2, each second frame part 220 has two protrusions 222, two recesses 224, and two blocking walls 226. However, the number of protrusions 222, the number of recesses 224, and the number of blocking walls 226 are not limited to two respectively.

[0021] Each second frame part main body 221 connects the pair of first frame parts 210 to each other. As shown in FIG. 5, each second frame part 220 has an upper surface S1 and a lower surface S2.

[0022] The two protrusions 222 are provided at positions spaced apart 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 protrusion 222 is provided on the upper surface S1 of the second frame body 221. The height of the protrusion 222 from the upper surface S1 is preferably set to be 5% or more and 75% or less of the height of the second frame body 221 (the dimension between the upper surface S1 and the lower surface S2).

[0023] As the protrusion 222 is spaced apart from the upper surface S1 of the second frame body 221, the cross-sectional area of the protrusion 222 in an orthogonal plane orthogonal to the vertical direction gradually decreases. In this embodiment, the protrusion 222 has a shape that curves convexly upward. Specifically, the protrusion 222 is formed in a semi-circular plate shape with substantially uniform thickness in the first direction. The protrusion 222 may be formed in a hemispherical shape.

[0024] 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 surface of the upper surface S1 and the lower surface S2 of the second frame body 221. In this 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 depresses upward from the lower surface S2. In this embodiment, the recess 224 opens to the outside in the direction (the first direction) connecting the pair of second frames 220.

[0025] The blocking wall 226 is formed inside the recess 224 in the direction connecting the pair of second frames 220. The blocking wall 226 blocks the electrode laminate 100 from the space outside the second frame 220.

[0026] As shown in FIG. 5, the partition wall 226 may have a guiding surface 226a. The guiding surface 226a is formed at the lower end of the partition wall 226. The guiding surface 226a guides the protrusion 222 toward the recess 224. More specifically, as indicated by the arrow in FIG. 5, when another power storage module 10 is stacked on one power storage module 10, the guiding surface 226a in the other power storage module 10 guides the protrusion 222 in one power storage module 10 toward the recess 224 in the other power storage module 10.

[0027] Note that the partition wall 226 may be omitted from the second frame portion 220, and the recess 224 may penetrate in the thickness direction (the first direction) of the second frame portion main body 221.

[0028] As shown in FIG. 1, the second frame portion 220 may have a stepped portion 228. The stepped portion 228 may protrude from the outer surface of the second frame portion main body 221 or may be recessed from the outer surface of the second frame portion main body 221. The stepped portion 228 may be used for hanging the finger of an operator, a hook of a hoist, etc. when the power storage module 10 is removed.

[0029] As described above, in the power storage device 1 according to the present embodiment, since the protrusion 222 of the second frame portion 220 in one power storage module 10 fits into the recess 224 of the second frame portion 220 in the power storage module 10 adjacent to the one power storage module 10, a plurality of power storage modules 10 are stacked while being effectively positioned with respect to each other. Further, since the second frame portion 220 different from the first frame portion 210 in which the liquid injection port 211 is formed has the protrusion 222 and the recess 224, both the degree of freedom in the design of the liquid injection port 211 and the degree of freedom in the design of the protrusion 222 and the recess 224 are ensured.

[0030] Further, since the power storage modules 10 adjacent to each other are positioned with respect to each other by the protrusion 222 and the recess 224, when the plurality of power storage modules 10 are constrained by the constraint plate from both sides in the stacking direction, even if the constraint load is relatively small (for example, 40 kN), the displacement between the power storage modules 10 that occurs when a collision under specified conditions is input can be suppressed to 10 mm or less.

[0031] Hereinafter, modified examples in the above-described embodiment will be described.

[0032] <First Modified Example> As shown in FIG. 6, the recess 224 opens inward in the direction (first direction) connecting the pair of second frame portions 220. The blocking wall 226 is formed outside the recess 224 in the direction connecting the pair of second frame portions 220.

[0033] <Second Modified Example> As shown in FIG. 7, 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 portion main body 221 as it goes inward in the direction (first direction) connecting the pair of second frame portions 220. 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 portion main body 221 as it goes inward in the first direction.

[0034] <Third Modified Example> As shown in FIG. 8, the top surface 222a of the protrusion 222 is inclined so as to gradually separate from the upper surface S1 of the second frame portion main body 221 as it goes 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 approach the upper surface S1 of the second frame portion main body 221 as it goes inward in the first direction.

[0035] <Fourth Modified Example> As shown in FIGS. 9 and 10, the protrusion 222 has a base portion 222b and a tip portion 222c.

[0036] The base portion 222b stands up from the upper surface S1 of the second frame portion main body 221. The base portion 222b has a shape in which the cross-sectional area of the base portion 222b in an orthogonal plane orthogonal to the vertical direction is uniform in the vertical direction. In the example shown in FIG. 9, the base portion 222b is formed in a columnar shape. However, the base portion 222b may be formed in an elliptical columnar shape, a polygonal columnar shape (such as a square columnar shape), or the like.

[0037] The tip portion 222c is provided on the base portion 222b. That is, the base portion 222b connects the upper surface S1 of the second frame portion main body 221 and the tip portion 222c. The tip portion 222c has a shape in which the cross-sectional area of the tip portion 222c in an orthogonal plane orthogonal to the vertical direction gradually decreases as it separates from the upper surface S1 of the second frame portion main body 221. In the example shown in FIG. 9, the tip portion 222c is formed in a frustum of a cone shape. However, the tip portion 222c may be formed in a frustum of an elliptical cone shape, a frustum of a pyramid shape, or the like.

[0038] <Fifth Modification> As shown in FIG. 11, the positions of the protrusions 222 and the recesses 224 in each power storage module 10 are offset from each other in the direction (second direction) connecting the pair of first frame portions 210. For example, the protrusion 222 in one power storage module 10 may be provided at a position offset in the direction (second direction) connecting the pair of first frame portions 210 from the protrusion 222 in the power storage module 10 adjacent to the one power storage module 10.

[0039] <Sixth Modification> As shown in FIG. 12, the pair of first frame portions 210 in each power storage module 10 includes an opposing frame portion 210B that opposes the liquid injection frame portion 210A. The opposing frame portion 210B has an opposing frame portion main body 216 that connects the pair of second frame portions 220, at least one protrusion 217 formed on the opposing frame portion main body 216, and at least one recess (not shown) formed on the opposing frame portion main body 216. The shapes of the protrusion 217 and the recess in the opposing frame portion 210B may be the same as or different from the shapes of the protrusion 222 and the recess 224 in the second frame portion 220.

[0040] <Seventh Modification Example> As shown in FIG. 13, the liquid injection frame portion 210A includes a liquid injection frame portion main body 213, at least one protrusion 214 formed on the liquid injection frame portion main body 213, and at least one recess 215 formed on the liquid injection frame portion main body 213. The protrusion 214 in the liquid injection frame portion 210A is formed at a portion of the upper surface of the liquid injection frame portion main body 213 that does not overlap with each liquid injection port 211 in the vertical direction. The recess 215 in the liquid injection frame portion 210A is formed at a portion of the lower surface of the liquid injection frame portion main body 213 that does not overlap with each liquid injection port 211 in the vertical direction. In the example shown in FIG. 13, both of the pair of first frame portions 210 have protrusions 214, 217 and recesses. Also, when at least one of the pair of first frame portions 210 has protrusions and recesses, the protrusions 222 and recesses 224 in one of the pair of second frame portions 220 may be omitted, or the protrusions 222 and recesses 224 in both of the pair of second frame portions 220 may be omitted.

[0041] Those skilled in the art will understand that the above-described exemplary embodiments and examples are specific examples of the following aspects.

[0042] [Aspect 1] Comprising a plurality of power storage modules stacked on each other, Each of the plurality of power storage modules, An electrode laminate including a plurality of electrodes stacked on each other, Having a shape surrounding the periphery of the electrode laminate and including a frame body that holds an edge portion of the electrode laminate, The frame body, A pair of first frame portions that face each other and hold a part of the edge portion of the electrode laminate, Each extending in a direction intersecting the first frame portion and facing each other, and including a pair of second frame portions that hold the remaining portion of the edge portion of the electrode laminate, One of the pair of first frame portions includes a liquid injection frame portion in which a liquid injection port for supplying an electrolytic solution to the electrode laminate is formed, At least one of the pair of second frame portions, A second frame portion body that connects the pair of first frame portions and has an upper surface and a lower surface, At least one protrusion provided on one of the upper surface and the lower surface of the second frame portion body, At least one recess provided on the other surface of the upper surface and the lower surface of the second frame portion body and having a shape that fits with the protrusion, The liquid injection frame portion has an upper surface and a lower surface, and a portion of the upper surface and the lower surface that overlaps the liquid injection port in the vertical direction is formed flat, a power storage device.

[0043] In this power storage device, since the protrusion of the second frame portion in one power storage module fits into the recess of the second frame portion in the power storage module adjacent to the one power storage module, displacement between the power storage modules stacked on each other is suppressed. Further, since the second frame portion different from the liquid injection frame portion in which the liquid injection port is formed has protrusions and recesses, and a portion of the upper surface and the lower surface of the liquid injection frame portion that overlaps the liquid injection port in the vertical direction is formed flat, both the degree of freedom in the design of the liquid injection port and the degree of freedom in the design of the protrusions and recesses are ensured.

[0044] [Aspect 2] The at least one protrusion includes a tip portion, The tip portion has a shape in which the cross-sectional area of the tip portion in an orthogonal plane orthogonal to the vertical direction gradually decreases as it separates from the one surface of the second frame portion body, the power storage device according to Aspect 1.

[0045] In this aspect, since it becomes easy to remove the power storage module stacked on one power storage module from the one power storage module, maintenance of the power storage device and replacement of the power storage module become easy.

[0046] [Aspect 3] The at least one protrusion further includes a base portion that connects the one surface of the second frame portion body and the tip portion, The base portion has a shape in which the cross-sectional area of the base portion in the orthogonal plane is uniform in the vertical direction, the power storage device according to Aspect 2.

[0047] [Aspect 4] The tip portion has a top surface, the top surface is gradually separated from the one surface or inclined so as to approach the one surface as it goes inward in the direction connecting the pair of second frame portions, The storage device according to Embodiment 2 or 3, wherein the recess has a contact surface that contacts the top surface.

[0048] In this aspect, by the top surface of the tip portion in one power storage module contacting the contact surface of the recess in the power storage module adjacent to the one power storage module, the power storage module adjacent to the one power storage module is effectively suppressed from being displaced in the direction connecting the pair of second frame portions with respect to the one power storage module.

[0049] [Aspect 5] The recess is open to the outside in the direction connecting the pair of second frame portions, The storage device according to any one of Aspects 1 to 4, wherein the second frame portion main body is formed inside the recess in the direction connecting the pair of second frame portions and includes a blocking wall that blocks the electrode laminate from the space outside the second frame portion.

[0050] In this aspect, positioning between a pair of adjacent power storage modules and ensuring the sealing property of the electrode laminate are achieved simultaneously.

[0051] [Aspect 6] The protrusion of one power storage module among the plurality of power storage modules is provided at a position offset in the direction connecting the pair of first frame portions from the protrusion of the power storage module adjacent to the one power storage module among the plurality of power storage modules. The storage device according to any one of Aspects 1 to 5.

[0052] [Aspect 7] The pair of first frame portions includes opposing frame portions that oppose the liquid injection frame portion, the opposing frame portions, connecting the pair of second frame portions to each other, and having an opposing frame portion body having an upper surface and a lower surface; at least one protrusion provided on either the upper surface or the lower surface of the opposing frame portion body; and at least one recess provided on the other surface of the opposing frame portion body and having a shape that fits with the protrusion, the power storage device according to any one of Aspects 1 to 6.

[0053] [Aspect 8] The liquid injection frame portion includes: a liquid injection frame portion body including 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 portion body that does not overlap with the liquid injection port in the vertical direction; and at least one recess provided at a portion of the other surface of the liquid injection frame portion body that does not overlap with the liquid injection port in the vertical direction and having a shape that fits with the protrusion, the power storage device according to any one of Aspects 1 to 7.

[0054] [Aspect 9] The height of the protrusion from the upper surface of the second frame portion body is set to be 5% or more and 75% or less of the dimension between the upper surface and the lower surface of the second frame portion body, the power storage device according to any one of Aspects 1 to 8.

[0055] [Aspect 10] The frame body is made of a thermoplastic resin, the power storage device according to any one of Aspects 1 to 9.

[0056] It should be noted that the embodiments disclosed this time should be considered as illustrative in all respects and not restrictive. The scope of the present disclosure is shown by the claims rather than the description of the above embodiments, and further includes all modifications within the meaning and scope equivalent to the claims.

Explanation of Reference Numerals

[0057] 1 Battery device, 10 Battery module, 100 Electrode laminate, 101 Edge portion, 110 Bipolar electrode, 120 Monopolar electrode, 200 Frame body, 210 First frame portion, 210A Liquid injection frame portion, 210B Opposing frame portion, 211 Liquid injection port, 212 Voltage detection terminal, 213 Liquid injection frame portion main body, 214 Projection, 215 Recess, 216 Opposing frame portion main body, 217 Projection, 220 Second frame portion, 221 Second frame portion main body, 222 Projection, 222a Top surface, 222b Base portion, 222c Tip portion, 224 Recess, 226 Partition wall, 226a Guide surface.

Claims

1. Comprising a plurality of power storage modules stacked on one another, each of the plurality of power storage modules includes an electrode laminate including a plurality of electrodes stacked on one another, and has a shape surrounding the periphery of the electrode laminate and includes a frame body that holds an edge portion of the electrode laminate, the frame body includes a pair of first frame portions that face each other and hold a part of the edge portion of the electrode laminate, and includes a pair of second frame portions that each extend in a direction intersecting the first frame portions and face each other and hold the remaining part of the edge portion of the electrode laminate, the pair of first frame portions includes a liquid injection frame portion in which a liquid injection port for supplying an electrolytic solution to the electrode laminate is formed, at least one of the pair of second frame portions includes a second frame portion main body that connects the pair of first frame portions and has an upper surface and a lower surface, and at least one protrusion provided on one of the upper surface and the lower surface of the second frame portion main body, and at least one recess provided on the other of the upper surface and the lower surface of the second frame portion main body and having a shape that fits with the protrusion, the liquid injection frame portion has an upper surface and a lower surface, and a portion of the upper surface and the lower surface that overlaps the liquid injection port in the vertical direction is formed flat, a power storage device.

2. the at least one protrusion includes a tip portion, the tip portion has a shape in which a cross-sectional area of the tip portion in an orthogonal plane orthogonal to the vertical direction gradually decreases as the tip portion moves away from the one surface of the second frame portion main body, the power storage device according to claim 1.

3. the at least one protrusion further includes a base portion that connects the one surface of the second frame portion main body and the tip portion, the base portion has a shape in which a cross-sectional area of the base portion in the orthogonal plane is uniform in the vertical direction, the power storage device according to claim 2.

4. the tip portion has a top surface, the top surface gradually moves away from or inclines closer to the one surface as it moves inward in the direction connecting the pair of second frame portions, the recess has a contact surface that contacts the top surface, the power storage device according to claim 2 or 3.

5. the recess opens to the outside in the direction connecting the pair of second frame portions, the second frame portion main body is formed inside the recess in the direction connecting the pair of second frame portions and includes a blocking wall that blocks the electrode laminate from a space outside the second frame portion, the power storage device according to claim 1.

6. The protrusion of one of the plurality of power storage modules in the plurality of power storage modules is provided at a position offset in a direction connecting the pair of first frame portions from the protrusion of the power storage module adjacent to the one power storage module among the plurality of power storage modules. The power storage device according to claim 1.

7. The pair of first frame portions includes opposing frame portions opposing the liquid injection frame portion, The opposing frame portion, connects the pair of second frame portions, and includes an opposing frame portion main body having an upper surface and a lower surface, at least one protrusion provided on either the upper surface or the lower surface of the opposing frame portion main body, and at least one recess provided on the other surface of the upper surface and the lower surface of the opposing frame portion main body and having a shape that fits with the protrusion. The power storage device according to claim 1.

8. The liquid injection frame portion, includes a liquid injection frame portion main body including the upper surface, the lower surface, and the liquid injection port, at least one protrusion provided at a portion that does not overlap the liquid injection port in the vertical direction on either the upper surface or the lower surface of the liquid injection frame portion main body, and at least one recess provided at a portion that does not overlap the liquid injection port in the vertical direction on the other surface of the upper surface and the lower surface of the liquid injection frame portion main body and having a shape that fits with the protrusion. The power storage device according to claim 1.

9. The height of the protrusion from the upper surface of the second frame portion main body is set to be 5% or more and 75% or less of the dimension between the upper surface and the lower surface in the second frame portion main body. The power storage device according to claim 1.

10. The frame body is made of a thermoplastic resin. The power storage device according to claim 1.

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