Energy storage module

Abstract

To provide a power storage module capable of suppressing the decrease in volume of a gas pocket.SOLUTION: A power storage module 1 includes an electrode multilayer body 10 including a plurality of bipolar electrodes 100, a positive electrode terminal electrode 200, and a negative electrode terminal electrode 300, a sealing part 500, and a buffer region formation member 600 to form a closed buffer region R2. Each bipolar electrode 100 includes a current collector 110, a positive electrode active material layer 120, and a negative electrode active material layer 130. The positive electrode terminal electrode 200 includes a positive electrode current collector foil 112 and a positive electrode active material layer 120. The negative electrode terminal electrode 300 includes a negative electrode foil 113 and a negative electrode active material layer 130. The sealing part 500 seals a region R1 in a state where a region R1 formed between a positive electrode non-applied part 112b and a negative electrode non-applied part 113b has lower pressure than atmospheric pressure. The buffer region formation member 600 forms the buffer region R2 at a position overlapping with the region R1 in a lamination direction.SELECTED DRAWING: Figure 2

Description

Technical Field

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

Background Art

[0002] Japanese Patent Application Laid-Open No. 2021-128898 discloses a power storage module including a plurality of bipolar electrodes, a plurality of separators disposed between adjacent bipolar electrodes, a sealing portion that seals a space formed between adjacent bipolar electrodes, and an electrolytic solution disposed in the space. The separator has a overlapping portion that overlaps with the electrode layer in the bipolar electrode and an exposed portion that does not overlap with the electrode layer when viewed from the stacking direction. The region where the exposed portion exists has a function of accommodating gas generated from the electrode during charge and discharge.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the power storage module described in Japanese Patent Application Laid-Open No. 2021-128898, the inside of the power storage module may be depressurized until it is below atmospheric pressure. In this case, the outermost electrode in the stacking direction may deform inward in the stacking direction due to the differential pressure between the inside and the outside of the power storage module.

[0005] On the other hand, since the region where the exposed portion of the separator exists has a function as a gas pocket that accommodates gas generated from the electrode during charge and discharge, when the outermost electrode in the stacking direction deforms inward, the volume of the gas pocket decreases.

[0006] An object of the present disclosure is to provide a power storage module capable of suppressing a decrease in the volume of a gas pocket.

Means for Solving the Problems

[0007] A power storage module according to an aspect of the present disclosure includes a plurality of bipolar electrodes stacked on one another, a positive terminal electrode disposed on one side of the plurality of bipolar electrodes in the stacking direction of the plurality of bipolar electrodes, and a negative terminal electrode disposed on the other side of the plurality of bipolar electrodes in the stacking direction. An electrode laminate including: a sealing portion that seals between a pair of electrodes adjacent to each other in the stacking direction of the electrode laminate; and a buffer region forming member that forms a sealed buffer region outside the electrode laminate in the stacking direction. Each of the plurality of bipolar electrodes has a current collector including a positive current collector foil and a negative current collector foil, a positive electrode active material layer provided on the positive current collector foil in the current collector, and a negative electrode active material layer provided on the negative current collector foil in the current collector. The positive terminal electrode has a positive current collector foil and a positive electrode active material layer provided on the positive current collector foil. The negative terminal electrode has a negative electrode foil and a negative electrode active material layer provided on the negative electrode foil. The positive current collector foil in each current collector and the positive current collector foil in the positive terminal electrode have a positive electrode coated portion provided with the positive electrode active material layer and a positive electrode uncoated portion not provided with the positive electrode active material layer. The negative current collector foil in each current collector and the negative current collector foil in the negative terminal electrode have a negative electrode coated portion provided with the negative electrode active material layer and a negative electrode uncoated portion that faces the positive electrode uncoated portion in the stacking direction and is not provided with the negative electrode active material layer. The sealing portion seals the region in a state where the region formed between the positive electrode uncoated portion and the negative electrode uncoated portion has a pressure lower than atmospheric pressure, and the buffer region forming member forms the buffer region at a position overlapping the region in the stacking direction.

Advantages of the Invention

[0008] According to the present disclosure, it is possible to provide a power storage module capable of suppressing a decrease in the volume of a gas pocket.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

MODE FOR CARRYING OUT THE INVENTION

[0010] 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.

[0011] (First Embodiment) FIG. 1 is a perspective view schematically showing a power storage module according to a first embodiment of the present disclosure. FIG. 2 is a cross-sectional view taken along line II-II in FIG. 1. As shown in FIGS. 1 and 2, the power storage module 1 includes an electrode laminate 10, a plurality of separators 400, a sealing portion 500, and a buffer region forming member 600.

[0012] The electrode laminate 10 has a plurality of bipolar electrodes 100, a positive terminal electrode 200, and a negative terminal electrode 300.

[0013] The plurality of bipolar electrodes 100 are laminated on each other. As shown in FIG. 2, each bipolar electrode 100 has a current collector 110, a positive electrode active material layer 120, and a negative electrode active material layer 130.

[0014] The current collector 110 is made of metal and is formed, for example, in a rectangular shape. The current collector 110 has a positive electrode current collector foil 112 and a negative electrode current collector foil 113. The positive electrode current collector foil 112 is made of, for example, aluminum. The negative electrode current collector foil 113 is made of, for example, copper foil. The negative electrode current collector foil 113 is adhered to the positive electrode current collector foil 112 by a conductive adhesive.

[0015] The positive electrode active material layer 120 is provided on one surface of the current collector 110, that is, on the surface of the positive electrode current collector foil 112. The negative electrode active material layer 130 is provided on the other surface of the current collector 110, that is, on the surface of the negative electrode current collector foil 113.

[0016] A plurality of bipolar electrodes 100 are laminated such that the positive electrode active material layer 120 in one bipolar electrode 100 and the negative electrode active material layer 130 in the bipolar electrode 100 adjacent to the one bipolar electrode 100 face each other.

[0017] The positive terminal electrode 200 is disposed on one side of the plurality of bipolar electrodes 100 in the stacking direction. The positive terminal electrode 200 has a positive electrode current collector foil 112 and a positive electrode active material layer 120 provided on the positive electrode current collector foil 112. The configurations of the positive electrode current collector foil 112 and the positive electrode active material layer 120 in the positive terminal electrode 200 are the same as those in the bipolar electrode 100.

[0018] The negative terminal electrode 300 is disposed on the other side of the plurality of bipolar electrodes 100 in the stacking direction. The negative terminal electrode 300 has a negative electrode current collector foil 113 and a negative electrode active material layer 130 provided on the negative electrode current collector foil 113. The configurations of the negative electrode current collector foil 113 and the negative electrode active material layer 130 in the negative terminal electrode 300 are the same as those in the bipolar electrode 100.

[0019] The positive electrode current collector foil 112 in each bipolar electrode 100 and the positive electrode current collector foil 112 in the positive terminal electrode 200 have a positive electrode coated portion 112a and a positive electrode uncoated portion 112b.

[0020] The positive electrode coating section 112a is the part where the positive electrode active material layer 120 is provided.

[0021] The uncoated section 112b of the positive electrode is the part where the positive electrode active material layer 120 is not provided, that is, the part where the positive electrode current collector foil 112 is exposed.

[0022] The negative electrode current collector foil 113 in each bipolar electrode 100 and the negative electrode current collector foil 113 in the negative electrode terminal electrode 300 have a negative electrode coating section 113a and an uncoated section 113b of the negative electrode.

[0023] The negative electrode coating section 113a is the part where the negative electrode active material layer 130 is provided.

[0024] The uncoated section 113b of the negative electrode is the part where the negative electrode active material layer 130 is not provided, that is, the part where the negative electrode current collector foil 113 is exposed. The uncoated section 113b of the negative electrode faces the uncoated section 112b of the positive electrode in the stacking direction.

[0025] Each separator 400 is disposed between a pair of electrodes 100, 200, 300 adjacent to each other in the stacking direction. Specifically, each separator 400 is disposed between the positive electrode active material layer 120 and the negative electrode active material layer 130. Each separator 400 is made of an insulating material and allows the permeation of ions. Examples of each separator 400 include a polyolefin microporous membrane.

[0026] The sealing portion 500 is made of an insulating material (such as resin). The sealing portion 500 seals between a pair of electrodes 100, 200, 300 that are adjacent to each other in the stacking direction in the electrode laminate 10. More specifically, the sealing portion 500 seals the region R1 (see FIG. 2) formed between the positive electrode non-coated portion 112b and the negative electrode non-coated portion 113b in a state where the pressure in the region R1 is lower than atmospheric pressure. An electrolytic solution is enclosed in this region R1. The sealing portion 500 holds the peripheral portions of the current collector foils 112 and 113 and the peripheral portions of the separators 400. The sealing portion 500 has a function of preventing leakage of the electrolytic solution from the region R1 and ingress of moisture from the outside into the region R1, and a function of ensuring the interval between the positive electrode non-coated portion 112b and the negative electrode non-coated portion 113b disposed so as to sandwich the region R1. The region R1 has a function as a gas pocket that accommodates the gas generated from the electrodes 100, 200, 300 during charge and discharge.

[0027] The buffer region forming member 600 forms a sealed buffer region R2 (see FIG. 2) outside the electrode laminate 10 in the stacking direction. As shown in FIG. 2, the buffer region forming member 600 forms the buffer region R2 at a position overlapping the region R1 in the stacking direction. The buffer region forming member 600 includes a positive electrode side conductive member 612, a positive electrode side conductive film 622, a positive electrode side holding portion 632, a positive electrode side support portion 642, a negative electrode side conductive member 613, a negative electrode side conductive film 623, a negative electrode side holding portion 633, and a negative electrode side support portion 643.

[0028] The positive electrode side conductive member 612 is disposed so as to contact the outer surface of the positive electrode coated portion 112a in the positive electrode terminal electrode 200. The positive electrode side conductive member 612 is formed in a flat plate shape. The positive electrode side conductive member 612 is made of aluminum, copper, or the like.

[0029] The positive electrode side conductive film 622 covers the positive electrode side conductive member 612. The positive electrode side conductive film 622 covers the entire outer surface of the positive electrode side conductive member 612. The positive electrode side conductive film 622 is made of aluminum or the like.

[0030] The positive electrode side holding portion 632 holds the peripheral edge portion of the positive electrode side conductive film 622 so as to form a buffer region R2 together with the positive electrode uncoated portion 112b, the positive electrode side conductive member 612, and the positive electrode side conductive film 622 in the positive electrode terminal electrode 200. The positive electrode side holding portion 632 is made of an insulating material (such as resin). The positive electrode side holding portion 632 is connected to the outer end surface of the sealing portion 500 in the stacking direction. The positive electrode side holding portion 632 may be made of the same material as the sealing portion 500 and may be integrally formed with the sealing portion 500.

[0031] As shown in FIG. 2, the portion of the positive electrode side conductive film 622 that defines the buffer region R2 (the portion between the positive electrode side conductive member 612 and the positive electrode side holding portion 632) is deformed inward in the stacking direction due to the differential pressure between the atmospheric pressure and the pressure in the region R1.

[0032] The positive electrode side support portion 642 is disposed between the positive electrode uncoated portion 112b and the positive electrode side conductive film 622 in the positive electrode terminal electrode 200. The positive electrode side support portion 642 supports the positive electrode side conductive film 622. The positive electrode side support portion 642 is made of an insulating material (such as resin). The positive electrode side support portion 642 has a shape extending from the positive electrode side holding portion 632 toward the positive electrode side conductive member 612. The positive electrode side support portion 642 may be made of the same material as the positive electrode side holding portion 632 and may be integrally formed with the positive electrode side holding portion 632. The positive electrode side support portion 642 is set to have a rigidity such that it can support the positive electrode side conductive film 622 deformed inward in the stacking direction. The positive electrode side support portion 642 may be in contact with the positive electrode uncoated portion 112b in the positive electrode terminal electrode 200 or may be spaced apart from the positive electrode uncoated portion 112b.

[0033] The negative electrode side conductive member 613, the negative electrode side conductive film 623, the negative electrode side holding portion 633, and the negative electrode side support portion 643 each have a configuration corresponding to the positive electrode side conductive member 612, the positive electrode side conductive film 622, the positive electrode side holding portion 632, and the positive electrode side support portion 642. Therefore, the description of the negative electrode side conductive member 613, the negative electrode side conductive film 623, the negative electrode side holding portion 633, and the negative electrode side support portion 643 is simplified.

[0034] The negative electrode side conductive member 613 is disposed so as to be in contact with the outer surface of the negative electrode coating portion 113a in the negative electrode terminal electrode 300.

[0035] The negative electrode side conductive film 623 covers the negative electrode side conductive member 613.

[0036] The negative electrode side holding portion 633 holds the peripheral edge portion of the negative electrode side conductive film 623 so as to form a buffer region R2 together with the negative electrode non-coated portion 113b, the negative electrode side conductive member 613, and the negative electrode side conductive film 623 in the negative electrode terminal electrode 300.

[0037] The negative electrode side support portion 643 is disposed between the negative electrode non-coated portion 113b and the negative electrode side conductive film 623 in the negative electrode terminal electrode 300. The negative electrode side support portion 643 supports the negative electrode side conductive film 623.

[0038] As described above, in the power storage module 1 according to the present embodiment, a sealed buffer region R2 is formed at a position overlapping in the stacking direction with the region R1 sealed in a state of being at a pressure lower than the atmospheric pressure. Since this buffer region R2 absorbs the differential pressure between the atmospheric pressure and the pressure in the region R1, the non-coated portions 112b, 113b in each of the terminal electrodes 200, 300 approach the non-coated portions 112b, 113b in the bipolar electrode 100 facing the non-coated portions 112b, 113b, that is, an increase in the volume of the gas pocket is suppressed.

[0039] Also, contact (occurrence of a short circuit) between the non-coated portions 112b, 113b in each of the terminal electrodes 200, 300 and the non-coated portions 112b, 113b in the bipolar electrode 100 facing the non-coated portions 112b, 113b is suppressed.

[0040] (Second Embodiment) Next, the power storage module 1 according to the second embodiment of the present disclosure will be described with reference to FIGS. 3 and 4. In the second embodiment, only the parts different from the first embodiment will be described, and the description of the same structure, operation, and effects as those of the first embodiment will not be repeated.

[0041] In this embodiment, the buffer region forming member 600 has a cover 650 and a seal portion 660.

[0042] The cover 650 covers the sealing portion 500. The cover 650 is composed of a so-called aluminum laminate film. That is, the cover 650 has an aluminum layer 651 and a resin layer 652 that covers the front and back surfaces of the aluminum layer 651. The cover 650 has an inner edge portion 654 formed at a position overlapping with the positive electrode coating portion 112a and the negative electrode coating portion 113a in the lamination direction. In other words, the cover 650 covers the entire outer surface of the non-coated positive electrode portion 112b in the positive electrode terminal electrode 200 and the entire outer surface of the non-coated negative electrode portion 113b in the negative electrode terminal electrode 300.

[0043] The seal portion 660 connects the cover 650 to the electrode laminate 10. Specifically, the seal portion 660 connects the inner edge portion 654 to the positive electrode coating portion 112a in the positive electrode terminal electrode 200 and the negative electrode coating portion 113a in the negative electrode terminal electrode 300.

[0044] Those skilled in the art will understand that the above-described exemplary embodiments and examples are specific examples of the following aspects.

[0045] [Aspect 1] An electrode laminate including a plurality of bipolar electrodes laminated on each other, a positive electrode terminal electrode disposed on one side of the plurality of bipolar electrodes in the lamination direction of the plurality of bipolar electrodes, and a negative electrode terminal electrode disposed on the other side of the plurality of bipolar electrodes in the lamination direction, A sealing portion that seals between a pair of electrodes adjacent to each other in the lamination direction of the electrode laminate, A buffer region forming member that forms a sealed buffer region outside the electrode laminate in the lamination direction, Each of the plurality of bipolar electrodes A current collector including a positive electrode current collector foil and a negative electrode current collector foil, A positive electrode active material layer provided on the positive electrode current collector foil in the current collector, It has a negative electrode active material layer provided on the negative electrode current collector foil in the current collector. The positive electrode terminal electrode has a positive electrode current collector foil and a positive electrode active material layer provided on the positive electrode current collector foil. The negative electrode terminal electrode has a negative electrode foil and a negative electrode active material layer provided on the negative electrode foil. In each of the current collectors, the positive electrode current collector foil in the positive electrode current collector and the positive electrode current collector foil in the positive electrode terminal electrode has a positive electrode coating part where the positive electrode active material layer is provided and a positive electrode non - coating part where the positive electrode active material layer is not provided. In each of the current collectors, the negative electrode current collector foil in the negative electrode current collector and the negative electrode current collector foil in the negative electrode terminal electrode has a negative electrode coating part where the negative electrode active material layer is provided and a negative electrode non - coating part that faces the positive electrode non - coating part in the stacking direction and where the negative electrode active material layer is not provided. The sealing part seals the region formed between the positive electrode non - coating part and the negative electrode non - coating part in a state where the pressure in the region is lower than atmospheric pressure. The buffer region forming member forms the buffer region at a position overlapping with the region in the stacking direction, a power storage module.

[0046] In this power storage module, a sealed buffer region is formed at a position overlapping in the stacking direction with the region sealed in a state of being lower than atmospheric pressure. Since this buffer region absorbs the differential pressure between atmospheric pressure and the pressure in the region, the non - coating part in each terminal electrode approaching the non - coating part in the bipolar electrode facing the non - coating part, that is, the decrease in the volume of the gas pocket is suppressed.

[0047] [Aspect 2] The buffer region forming member has a positive electrode side conductive member arranged to contact the outer surface of the positive electrode coating part in the positive electrode terminal electrode and a positive electrode side conductive film covering the positive electrode side conductive member. A positive electrode side holding portion that holds a peripheral edge portion of the positive electrode side conductive film so as to form the buffer region together with the positive electrode uncoated portion, the positive electrode side conductive member, and the positive electrode side conductive film in the positive electrode terminal electrode; A negative electrode side conductive member disposed so as to be in contact with an outer surface of the negative electrode coated portion in the negative electrode terminal electrode; A negative electrode side conductive film that covers the negative electrode side conductive member; A negative electrode side holding portion that holds a peripheral edge portion of the negative electrode side conductive film so as to form the buffer region together with the negative electrode uncoated portion, the negative electrode side conductive member, and the negative electrode side conductive film in the negative electrode terminal electrode, the power storage module according to aspect 1.

[0048] In this aspect, the positive electrode side conductive film and the negative electrode side conductive film are deformed inward in the stacking direction, so that the compressive force due to atmospheric pressure is absorbed. Therefore, a decrease in the volume of the gas pocket is effectively suppressed.

[0049] Further, since the outer surface of the power storage module in the stacking direction is composed of the positive electrode side conductive film and the negative electrode side conductive film, it is possible to stack a plurality of power storage modules via a conductive member (such as a current collector plate).

[0050] [Aspect 3] A positive electrode side support portion that is disposed between the positive electrode uncoated portion and the positive electrode side conductive film in the positive electrode terminal electrode and supports the positive electrode side conductive film; A negative electrode side support portion that is disposed between the negative electrode uncoated portion and the negative electrode side conductive film in the negative electrode terminal electrode and supports the negative electrode side conductive film, the power storage module according to aspect 2.

[0051] In this aspect, since each conductive film is supported by each support portion, a decrease in the volume of the gas pocket is more reliably suppressed.

[0052] [Aspect 4] The buffer region forming member is A cover that covers the sealing portion It has a sealing part that connects the cover to the electrode laminate. The cover has an inner edge formed at a position overlapping the positive electrode coating part and the negative electrode coating part in the stacking direction. The power storage module according to Aspect 1, wherein the sealing part connects the inner edge to the electrode laminate.

[0053] In this aspect, the portion of the cover that overlaps the region in the stacking direction is deformed inward in the stacking direction, thereby absorbing the compressive force due to atmospheric pressure.

[0054] Further, by arranging a conductive member (such as a current collector plate) at a portion of each terminal electrode that is not covered by the cover, it becomes possible to stack a plurality of power storage modules.

[0055] It should be noted that the embodiments disclosed this time are illustrative in all respects and should not be considered restrictive. The scope of the present invention is shown by the scope of claims rather than the description of the above embodiments, and further includes all modifications within the meaning and scope equivalent to the scope of claims.

Explanation of Reference Numerals

[0056] 1 Power storage module, 10 Electrode laminate, 100 Bipolar electrode, 110 Current collector, 112 Positive electrode current collecting foil, 112a Positive electrode coating part, 112b Uncoated positive electrode part, 113 Negative electrode current collecting foil, 113a Negative electrode coating part, 113b Uncoated negative electrode part, 120 Positive electrode active material layer, 130 Negative electrode active material layer, 200 Positive electrode terminal electrode, 300 Negative electrode terminal electrode, 400 Separator, 500 Sealing part, 600 Buffer region forming member, 612 Positive electrode side conductive member, 613 Negative electrode side conductive member, 622 Positive electrode side conductive film, 623 Negative electrode side conductive film, 632 Positive electrode side holding part, 633 Negative electrode side holding part, 642 Positive electrode side support part, 643 Negative electrode side support part, 650 Cover, 654 Inner edge, 660 Sealing part, R1 Region, R2 Buffer region.

Claims

1. An electrode laminate including a plurality of bipolar electrodes, a positive terminal electrode, and a negative terminal electrode; A sealing portion that seals between a pair of electrodes adjacent to each other in the stacking direction of the electrode laminate; A buffer region forming member that forms a sealed buffer region outside the electrode laminate in the stacking direction, and comprising: The positive current collector foil in each bipolar electrode and the positive current collector foil in the positive terminal electrode have a positive electrode coating portion and a non-coated positive electrode portion; The negative current collector foil in each bipolar electrode and the negative current collector foil in the negative terminal electrode have a negative electrode coating portion and a non-coated negative electrode portion; The sealing portion seals the region in a state where the region formed between the non-coated positive electrode portion and the non-coated negative electrode portion has a pressure lower than atmospheric pressure; The buffer region forming member forms the buffer region at a position overlapping the region in the stacking direction; The buffer region forming member A positive electrode side conductive film provided outside the positive terminal electrode and outside the region in the stacking direction; A negative electrode side conductive film provided outside the negative terminal electrode and outside the region in the stacking direction; At least one insulating member disposed in the buffer region, a power storage module.

2. An electrode laminate including a plurality of bipolar electrodes, a positive terminal electrode, and a negative terminal electrode; A sealing portion that seals between a pair of electrodes adjacent to each other in the stacking direction of the electrode laminate; A buffer region forming member that forms a sealed buffer region outside the electrode laminate in the stacking direction, and comprising: The positive current collector foil in each bipolar electrode and the positive current collector foil in the positive terminal electrode have a positive electrode coating portion and a non-coated positive electrode portion; The negative current collector foil in each bipolar electrode and the negative current collector foil in the negative terminal electrode have a negative electrode coating portion and a non-coated negative electrode portion; The sealing portion seals the region in a state where the region formed between the non-coated positive electrode portion and the non-coated negative electrode portion has a pressure lower than atmospheric pressure; The buffer region forming member forms the buffer region at a position overlapping the region in the stacking direction; The buffer region forming member A positive electrode side conductive member disposed in contact with the outer surface of the positive electrode coating portion in the positive terminal electrode; A positive electrode side conductive film covering the positive electrode side conductive member; A positive electrode side holding portion that holds a peripheral edge portion of the positive electrode side conductive film so as to form the buffer region together with the positive electrode non-coated portion, the positive electrode side conductive member, and the positive electrode side conductive film in the positive electrode terminal electrode; A positive electrode side support portion that is disposed between the positive electrode non-coated portion and the positive electrode side conductive film in the positive electrode terminal electrode and supports the positive electrode side conductive film; A negative electrode side conductive member disposed so as to be in contact with an outer surface of the negative electrode coated portion in the negative electrode terminal electrode; A negative electrode side conductive film that covers the negative electrode side conductive member; A negative electrode side holding portion that holds a peripheral edge portion of the negative electrode side conductive film so as to form the buffer region together with the negative electrode non-coated portion, the negative electrode side conductive member, and the negative electrode side conductive film in the negative electrode terminal electrode; A negative electrode side support portion that is disposed between the negative electrode non-coated portion and the negative electrode side conductive film in the negative electrode terminal electrode and supports the negative electrode side conductive film, the power storage module having the same.

3. An electrode laminate including a plurality of bipolar electrodes, a positive electrode terminal electrode, and a negative electrode terminal electrode; A sealing portion that seals between a pair of electrodes adjacent to each other in the stacking direction in the electrode laminate; A buffer region forming member that forms a sealed buffer region outside the electrode laminate in the stacking direction, the power storage module including the same; The positive electrode current collector foil in each of the bipolar electrodes and the positive electrode current collector foil in the positive electrode terminal electrode have a positive electrode coated portion and a positive electrode non-coated portion; The negative electrode current collector foil in each of the bipolar electrodes and the negative electrode current collector foil in the negative electrode terminal electrode have a negative electrode coated portion and a negative electrode non-coated portion; The sealing portion seals the region in a state where the region formed between the positive electrode non-coated portion and the negative electrode non-coated portion has a pressure lower than atmospheric pressure; The buffer region forming member forms the buffer region at a position overlapping the region in the stacking direction; The buffer region forming member Has a cover that covers the sealing portion; A seal portion that connects the cover to the electrode laminate; The cover has an inner edge portion formed at a position overlapping the positive electrode coated portion and the negative electrode coated portion in the stacking direction; The seal portion connects the inner edge portion to the positive electrode coated portion in the positive electrode terminal electrode and the negative electrode coated portion in the negative electrode terminal electrode, the power storage module having the same.

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