JP2014035916A - Power storage device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power storage device capable of facilitating insertion of an electrode assembly into a case.SOLUTION: An electrode assembly 14 of a secondary battery 10 has an opposed part T including a cathode active material layer and an anode active material layer opposed to the cathode active material layer and a non-opposed part 24 extending from the opposed part T in a direction along the surface of the cathode active material layer and having no cathode active material layer. The non-opposed part 24 is gathered up toward opposite ends in laminate direction of the electrode assembly 14, and protrudes in laminate direction than an end face along a direction orthogonal to the laminate direction of the electrode assembly 14 on the gathered side. Furthermore, adhesive tape 25 stuck over the gathered non-opposed part 24 is stuck to the opposed part T on the gathered end face.

Description

  The present invention relates to an electrode assembly in which a positive electrode sheet having a positive electrode active material layer formed on at least one surface, a negative electrode sheet having a negative electrode active material layer formed on at least one surface, and a separator are laminated. It is related with the electrical storage apparatus provided with.

  A vehicle such as an EV (Electric Vehicle) or a PHV (Plug in Hybrid Vehicle) is equipped with a secondary battery as a power storage device that stores power supplied to the traveling motor. The secondary battery includes, for example, a positive electrode sheet and a negative electrode sheet having active material layers formed on both surfaces, and an electrode assembly in which these are stacked with a separator interposed therebetween. An example of such an electrode assembly is described in Patent Document 1.

  As shown in FIG. 7, in Patent Document 1, an electrode stack 80 (electrode assembly) is an electrode 81 (positive electrode sheet and negative electrode sheet) formed by applying an active material layer to one or both sides of a current collector. Are stacked with a separator 82 interposed therebetween. The electrode laminate 80 has adhesive members 83 attached to four side surfaces, and the electrode laminate 80 is fixed in the laminating direction by the fixing members 83. And the electrode laminated body 80 by which the shift | offset | difference to the direction along the surface of the electrode 81 and the lamination direction was prevented by the fixing member 83 is accommodated in an exterior body (not shown), and the electrical storage apparatus is formed.

JP 2010-80324 A

  By the way, in the power storage device, when the electrode stack 80 is inserted into the exterior body, it is necessary to perform an insertion operation so that the electrode 81 and the exterior body are not damaged by the contact between the electrode 81 and the exterior body. Improvement of the workability of the work of inserting the electrode laminate 80 into the body is desired. In addition, depending on how the fixing member 83 is fixed, the electrode 81 may be displaced and it may be difficult to insert the electrode stack 80 into the exterior body.

  An object of the present invention is to provide a power storage device that can facilitate insertion of an electrode assembly into a case.

  In order to solve the above problems, the invention according to claim 1 is characterized in that the positive electrode active material layer is formed on at least one surface, and the negative electrode active material layer is formed on at least one surface. In a power storage device in which a negative electrode sheet and an electrode assembly configured by laminating a separator interposed between the positive electrode sheet and the negative electrode sheet are housed in a case, the electrode assembly includes the positive electrode active material layer And a facing portion including the negative electrode active material layer facing the positive electrode active material layer, and extending from the facing portion in a direction along a surface of the positive electrode active material layer and the negative electrode active material layer, and the positive electrode active material And a non-opposing portion to which the negative electrode active material layer is not applied, and the non-opposing portion is gathered toward at least one end of both ends in the stacking direction of the electrode assembly in the opposing portion. Et And projecting in the laminating direction from the end surface along the direction orthogonal to the laminating direction of the electrode assembly on the gathered side, and further covering and pasting at least the tip of the gathered non-opposing portion. The gist is that the adhesive tape is stuck to the facing portion on the end face on the gathered side.

  According to this, the adhesive tape is stuck to the gathered non-opposing part, and the adhesive tape is stuck to the opposing part of the end surface on the gathered side. Therefore, the adhesive tape is stuck to the opposing part in a state of being pulled toward the gathered side of the non-opposing part. Therefore, the electrode assembly can be positioned together with the non-opposing portion by the adhesive tape. Therefore, since an electrode assembly with no positional deviation can be inserted into the case, the insertion operation can be easily performed. Further, the gathered non-opposing part protrudes outward from the facing part on the gathered side end face. For this reason, when the electrode assembly is inserted into the case, the collected non-opposing portion functions as a cushioning material between the opposing portion and the case. Therefore, when the electrode assembly is inserted into the case, it is not necessary to insert it carefully while paying attention to the contact between the case and the facing portion (particularly the positive electrode active material layer), and the electrode assembly can be easily inserted into the case. it can.

The non-facing portion may be gathered separately on both end face sides in the stacking direction of the electrode assembly.
According to this, the gathered non-opposing portions protrude at both end sides in the stacking direction of the electrode assembly, and the contact of the positive electrode active material layer and the negative electrode active material layer to the case is determined in the stacking direction of the electrode assembly. It is possible to prevent any of both end sides.

Moreover, the both ends of the said adhesive tape may be stuck on the opposing part of both the end surfaces of the said lamination direction, and the said adhesive tape may be stuck ranging over the two non-opposing parts gathered together.
According to this, the two non-opposing parts gathered together can be collectively positioned with the adhesive tape.

Moreover, the said adhesive tape may be affixed on the position which the said electrode assembly opposes.
According to this, in order to prevent displacement of the electrode assembly, the amount of the adhesive tape used can be reduced as compared with the case where the adhesive tape is attached to the four side surfaces of the electrode assembly.

Moreover, the said adhesive tape may be stuck so that a part of said electrode assembly may be covered.
According to this, the usage-amount of an adhesive tape can be reduced.
The power storage device may be a secondary battery. According to this, the insertion property of the electrode assembly into the case can be facilitated.

  ADVANTAGE OF THE INVENTION According to this invention, the insertability to the case of an electrode assembly can be made easy.

The exploded perspective view of a secondary battery. The perspective view which shows the external appearance of a secondary battery. The disassembled perspective view which shows the component of an electrode assembly. The fragmentary sectional view which shows the electrode assembly and integration | stacking part in a container. The perspective view which shows the electrode assembly of another example. The perspective view which shows the electrode assembly of another example. The figure which shows background art.

  Hereinafter, an embodiment embodying the present invention will be described with reference to FIGS. A plurality of power storage devices are mounted on vehicles (automobiles and industrial vehicles), and are used to drive a traveling motor (electric motor) mounted on the vehicle. For convenience of drawing, the length of the non-opposing portion shown in FIG. 3 and the like are shown as being appropriately different from the actual dimensions.

  As shown in FIGS. 1 and 2, a secondary battery 10 as a power storage device includes a metal case 11 that forms an outer shell thereof. The case 11 includes a rectangular box-shaped container 12 and a rectangular flat lid 13 that closes the opening of the container 12. For this reason, the secondary battery 10 has a rectangular outer shape. Note that the secondary battery 10 of the present embodiment is a lithium ion secondary battery. The case 11 contains an electrode assembly 14 and an electrolytic solution (not shown) as an electrolyte.

  As shown in FIG. 3, the electrode assembly 14 includes a separator 23 in which a plurality of positive electrode sheets 21 and a plurality of negative electrode sheets 22 are formed of a porous film through which ions (lithium ions) related to electric conduction can pass. And are alternately stacked. Specifically, the electrode assembly 14 insulates the positive electrode sheet 21 and the negative electrode sheet 22 by interposing a sheet-like separator 23 between the positive electrode sheet 21 and the negative electrode sheet 22, and stacks a plurality of these in a certain direction. Configured.

  The positive electrode sheet 21 includes a positive electrode metal foil (for example, an aluminum foil) 21a formed in a rectangular shape, and a positive electrode active material layer 21b formed by applying a positive electrode active material on both surfaces of the positive electrode metal foil 21a. Has been. The negative electrode sheet 22 includes a negative electrode metal foil (for example, copper foil) 22a formed in a rectangular shape, and a negative electrode active material layer 22b formed by applying a negative electrode active material on both surfaces of the negative electrode metal foil 22a. Has been. As the negative electrode active material, a mixture of graphite and silicon dioxide can be used, including a material having a thermal conductivity lower than that of the carbon-based active material, and lithium ions. Use removable material. In addition, silicon monoxide (silicon monoxide, SiO), lithium titanate, and lithium silicate can be used.

  The positive electrode sheet 21 is provided with a positive electrode current collecting tab 31 formed by extending the positive electrode metal foil 21 a at a part of one end portion 21 c (one side direction (long side direction)) of the positive electrode sheet 21. . Similarly to the positive electrode sheet 21, the negative electrode sheet 22 is formed by extending the negative electrode metal foil 22 a at a part of one end 22 c (one side direction (long side direction)) of the negative electrode sheet 22. A current collecting tab 32 is provided.

  As shown in FIG. 1, the positive electrode sheet 21 and the negative electrode sheet 22 are arranged such that the positive electrode current collecting tabs 31 are arranged in a row along the stacking direction, and the negative electrode current collecting tabs 32 are not overlapped with the positive electrode current collecting tab 31. Are stacked in a row along the stacking direction. Each positive electrode current collecting tab 31 is bent in a state of being collected (bundled) within a range from one end to the other end in the stacking direction of the electrode assembly 14. Specifically, each positive electrode current collecting tab 31 is gathered toward one end side in the stacking direction of the electrode assembly 14, and in the gathered state, other positive electrode current collecting tabs 31 are arranged in the stacking direction opposite to the one end side. It is folded toward the end side. And each positive electrode current collection tab 31 is electrically connected by welding the location where the each positive electrode current collection tab 31 has overlapped. The same applies to each negative electrode current collecting tab 32.

  As shown in FIGS. 1 and 2, the secondary battery 10 includes a positive terminal 41 and a negative terminal 42 for extracting power from the electrode assembly 14. Each terminal 41, 42 is attached in a state of penetrating the case 11 through a through hole 13 a formed in the lid 13 of the case 11, and a part of the terminal 41 is exposed to the outside of the case 11. In addition, ring-shaped insulating rings 13 b for insulating from the case 11 are attached to the positive terminal 41 and the negative terminal 42, respectively.

  The positive terminal 41 is electrically connected to each welded positive current collecting tab 31, and the negative terminal 42 is electrically connected to each welded negative current collecting tab 32. Thereby, the electric power of the electrode assembly 14 can be taken out of the case 11 and the electrode assembly 14 can be charged by supplying electric power to the electrode assembly 14.

  Further, negative electrode sheets 22 are provided at both ends of the electrode assembly 14 in the stacking direction. Thereby, the area | region which does not oppose the negative electrode active material layer 22b in the positive electrode active material layer 21b in the both ends of the lamination direction in the electrode assembly 14 is prevented from being formed. Further, in order to suppress a short circuit between the electrode assembly 14 (specifically, the outermost negative electrode sheet 22) and the container 12, an insulating sheet is provided between the side surface in the stacking direction of the electrode assembly 14 and the inner surface of the container 12. 30 is provided.

  As shown in FIG. 3, the positive electrode sheet 21 (rectangular portion excluding the positive electrode current collecting tab 31) and the negative electrode sheet 22 (rectangular portion excluding the negative electrode current collecting tab 32) have a similar shape. Yes. Specifically, the positive electrode sheet 21 is formed smaller than the negative electrode sheet 22. The length of one side direction (long side direction) and the other side direction (short side direction) of the positive electrode sheet 21 (positive electrode metal foil 21a) is set shorter than the length of each direction of the negative electrode sheet 22 (negative electrode metal foil 22a). Has been.

  Since the positive electrode sheet 21 is formed smaller than the negative electrode sheet 22, the positive electrode active material layer 21b is formed smaller than the negative electrode active material layer 22b. As shown by a two-dot chain line in FIG. 3, in the separator 23 and the negative electrode sheet 22, a portion of the positive electrode sheet 21 that faces the positive electrode active material layer 21 b constitutes a facing portion T in the electrode assembly 14. In the positive electrode sheet 21, the positive electrode active material layer 21 b itself also constitutes a part of the facing portion T. Further, in the separator 23 and the negative electrode sheet 22, a portion that protrudes outward from the edge of the positive electrode active material layer 21 b in a direction along the surface of the positive electrode active material layer 21 b is formed as a non-facing portion 24 that does not face the positive electrode active material layer 21 b. Forming. The non-opposing portions 24 surround the four sides of the positive electrode active material layer 21 b and are provided on the four sides of the electrode assembly 14.

  As shown in FIGS. 1 and 4, two accumulation portions 26 are formed on both short sides of the electrode assembly 14 by gathering the non-opposing portions 24 together. Each integrated portion 26 divides the non-facing portion 24 toward both ends of the electrode assembly 14 in the stacking direction, and further, the non-facing portion 24 faces the facing portion T of the negative electrode sheet 22 on both ends in the stacking direction. It is formed in a bent state. In each stacking portion 26, the non-opposing portion 24 on the center side in the stacking direction of the electrode assembly 14 is positioned on the outside so as to cover the stacking portion 26, and the non-facing portion 24 on both ends in the stacking direction is on the inside of the stacking portion 26. Is located. The non-opposing portions 24 provided on both short sides of the electrode assembly 14 have the same protruding length from the positive electrode active material layer 21b. Therefore, each integrated portion 26 is formed so as to gradually incline as it separates from both ends (negative electrode sheet 22) in the stacking direction of the electrode assembly 14 along the stacking direction, and each non-facing portion is formed on the inclined surface. 24 tips are arranged.

  The adhesive tape 25 is applied to the opposing portions T of the negative electrode sheets 22 in a state where each non-opposing portion 24 exposed in the outermost layer of each collecting portion 26 is pulled toward the end surface on the side where each collecting portion 26 is gathered. It is stuck. Note that the end surface on the side where the integrated portions 26 are gathered together is an end surface along a direction orthogonal to the stacking direction of the electrode assembly 14 and is an end surface positioned at both ends in the stacking direction.

  Each integrated portion 26 is pressed toward the positive electrode active material layer 21 b in the long side direction of the electrode assembly 14, and pressed toward the negative electrode sheets 22 at both ends in the stacking direction of the electrode assembly 14. . For this reason, in each stacking part 26, the non-opposing parts 24 adjacent in the stacking direction are positioned with the adhesive tape 25 in a state of being in close contact with each other.

  Further, each integrated portion 26 protrudes outward from the negative electrode sheets 22 on both ends in the stacking direction of the electrode assembly 14. As shown in FIG. 4, the protruding length L of the integrated portion 26 from the negative electrode sheet 22 is obtained by adding the thickness of the adhesive tape 25 to the total thickness of the non-facing portions 24 stacked in the stacking direction of the electrode assembly 14. Value. Let K be the length of the gap between the negative electrode sheet 22 on the end face of the electrode assembly 14 in the stacking direction and the insulating sheet 30. In this case, the protruding length L of the stacking portion 26 before the electrode assembly 14 is accommodated in the container 12 is set slightly longer than the length K of the gap. When the electrode assembly 14 is accommodated in the container 12, the stacking portion 26 is slightly compressed, and the protruding length L becomes the same as the length K of the gap.

The operation of the secondary battery 10 of the present embodiment will be described below.
In the electrode assembly 14, on both short sides, a stacking portion 26 is formed that is positioned by the adhesive tape 25 in a state where the non-opposing portions 24 are gathered together at both ends in the stacking direction. The adhesive tape 25 is attached to both the stacking portions 26 while pulling the non-facing portion 24 so that the non-facing portions 24 are in close contact with each other in the stacking portion 26, and is opposed to the negative electrode sheets 22 at both ends in the stacking direction. Affixed to the part T. For this reason, the electrode assembly 14 is strongly positioned by the adhesive tape 25 in the laminating direction and in the direction along the surfaces of the active material layers 21b and 22b, and displacement in each direction is prevented.

  Further, each integrated portion 26 protrudes outside the negative electrode sheet 22 on both ends in the stacking direction of the electrode assembly 14. For this reason, when the electrode assembly 14 is inserted into the container 12, it can be inserted while pressing the outer surface of each stacking portion 26 against the inner surface of the insulating sheet 30. Therefore, the accumulation unit 26 functions as a buffer material between the electrode assembly 14 and the container 12.

According to the above embodiment, the following effects can be obtained.
(1) In the electrode assembly 14, the non-facing portion 24 that does not face the positive electrode active material layer 21 b and the negative electrode active material layer 22 b and extends outward from the positive electrode active material layer 21 b is formed in the stacking direction of the electrode assembly 14. The both ends of the electrode assembly 14 were positioned with the adhesive tape 25 and the integrated portions 26 were provided on both short sides of the electrode assembly 14. And the accumulation | aggregation part 26 is formed by affixing on the both negative electrode sheets 22 in the state which pulled the adhesive tape 25 toward the end surface side of the lamination direction of the electrode assembly 14. FIG. Therefore, the electrode assembly 14 can be positioned by the adhesive tape 25, and the electrode assembly 14 can be prevented from being displaced in the direction along the surfaces of the active material layers 21b and 22b and in the stacking direction. Therefore, since the electrode assembly 14 without misalignment can be inserted into the container 12, the insertion operation can be easily performed.

  In addition, each of the accumulation portions 26 protrudes outward from the negative electrode sheets 22 on both ends in the stacking direction of the electrode assemblies 14. For this reason, when the electrode assembly 14 is inserted into the container 12, the stacking portion 26 can be inserted while being pressed against the insulating sheet 30 in the container 12. Therefore, the accumulation part 26 functions as a buffer material, and the facing part T of the electrode assembly 14 can be prevented from coming into direct contact with the insulating sheet 30.

  In particular, the protruding length L of the integrated portion 26 from the negative electrode sheet 22 on both ends in the stacking direction is the gap between the opposing portion T (negative electrode sheet 22) on both ends in the stacking direction of the electrode assembly 14 and the insulating sheet 30. Is set to be slightly longer than the length K. For this reason, when the electrode assembly 14 is inserted into the container 12, the stacking portion 26 is deformed while being pressed against the inner surface of the insulating sheet 30, and the electrode assembly 14 is held in the container 12 by the deformation. 14 can be prevented from falling. Therefore, it is possible to prevent the electrode assembly 14 from falling and colliding with the inner surface of the container 12 via the insulating sheet 30. Therefore, it is not necessary to insert the electrode assembly 14 into the container 12 without worrying about the drop of the electrode assembly 14 into the container 12 and the contact with the positive electrode active material layer 21b.

  (2) The integrated portion 26 is provided on both short sides of the electrode assembly 14 and is provided separately on both ends in the stacking direction. For this reason, the accumulation part 26 protrudes at both ends in the stacking direction of the electrode assembly 14, and the contact of the facing part T (the positive electrode active material layer 21 b and the negative electrode active material layer 22 b) with the inner surface of the container 12 is performed. Any of the both end sides in the stacking direction of 14 can be prevented.

  (3) On both short sides of the electrode assembly 14, the integrated portions 26 are provided separately on both ends in the stacking direction, and the adhesive tape 25 is stuck across the two integrated portions 26. That is, the adhesive tape 25 is collectively attached to the negative electrode sheet 22 so as to cover the two integrated portions 26 from the opposing portions T of the negative electrode sheet 22 on both ends in the stacking direction of the electrode assembly 14. Therefore, the two stacked portions 26 can be suitably positioned by the adhesive tape 25.

  (4) Each stacking portion 26 is pulled by the adhesive tape 25 toward the facing portion T on both ends in the stacking direction. For this reason, in each integrated part 26, the non-opposing parts 24 are in close contact with each other, and the displacement of the electrode assembly 14 in the stacking direction can be reliably prevented.

  (5) The stacking portion 26 is provided on both short sides of the electrode assembly 14, and the adhesive tape 25 is placed at a position facing the electrode assembly 14 (both short sides) in order to position the stacking portion 26. It is stuck. Therefore, compared with the case where the adhesive tape 25 is stuck on the four side surfaces of the electrode assembly 14 in order to prevent the electrode assembly 14 from being displaced, the amount of the adhesive tape 25 used can be reduced.

  (6) The integrated portions 26 protrude outward from the negative electrode sheets 22 at both ends in the stacking direction of the electrode assemblies 14. For this reason, when the electrode assembly 14 is accommodated in the case 11, a gap is formed between the facing portion T of the electrode assembly 14 and the inner surface of the container 12 (insulating sheet 30). Therefore, even if the entire electrode assembly 14 expands in the stacking direction due to charging of the secondary battery 10, the expansion can be allowed by the gap.

In addition, you may change the said embodiment as follows.
In the embodiment, the integrated portions 26 are provided on both short sides of the electrode assembly 14, and the integrated portions 26 are positioned with separate adhesive tapes 25 on each short side. However, as shown in FIG. Alternatively, the adhesive tape 25 may be attached to the electrode assembly 14 so as to surround the entire 14, and all the stacking portions 26 may be positioned by the single adhesive tape 25.

  In the embodiment, the integrated part 26 is provided on both short sides of the electrode assembly 14, but the position where the integrated part 26 is provided may be changed as appropriate. For example, as shown in FIG. 6, the integrated part 26 may be provided on the electrode assembly 14 on the opposite side (long side) to the side where the positive electrode current collecting tab 31 and the negative electrode current collecting tab 32 are provided.

  In the embodiment, the adhesive tape 25 is stuck to the two stacking portions 26 across the opposing portions T of the negative electrode sheets 22 on both end sides in the stacking direction. The other end side may be adhered to the facing portion T of the one negative electrode sheet 22 in a state where the distal end portion of the negative electrode sheet 22 is adhered. That is, as long as the stacking portion 26 can be positioned, the manner of sticking the adhesive tape 25 may be appropriately changed.

  In the embodiment, the two non-opposing portions 24 are gathered toward the both end sides in the stacking direction of the electrode assembly 14 to form the two integrated portions 26, but the number of the integrated portions 26 may be one. That is, the non-opposing portion 24 may be gathered toward one end side in the stacking direction of the electrode assembly 14 to form one integrated portion 26.

  In the embodiment, the two stacking portions 26 are formed separately from the center of the non-facing portion 24, but the number of the non-facing portions 24 forming each stacking portion 26 may be appropriately changed. For example, the non-opposing portion 24 that forms the collecting portion 26 gathered on one end side in the stacking direction may be less than the non-facing portion 24 that forms the collecting portion 26 gathered on the other end side in the stacking direction. Or vice versa.

  In the embodiment, the non-opposing portion 24 is a portion that does not oppose the positive electrode active material layer 21 b in the separator 23 and the negative electrode sheet 22, but the negative electrode active material layer 22 b is not used as the non-opposing portion 24. The non-facing portion 24 may be formed only at a portion that does not face the active material layer 21b.

  In the embodiment, the positive electrode current collecting tab 31 and the negative electrode current collecting tab 32 are folded in a state of being collected (bundled) within a range from one end to the other end in the stacking direction of the electrode assembly 14. However, the positive electrode current collecting tab 31 and the negative electrode current collecting tab 32 may not be collected.

The positive electrode active material layer 21b and the negative electrode active material layer 22b may be formed on one side of the positive electrode metal foil 21a and the negative electrode metal foil 22a.
The number of the positive electrode sheet 21 and the negative electrode sheet 22 constituting the electrode assembly 14 may be changed as appropriate.

The shape of the case 11 may be formed in a columnar shape or an elliptical column shape that is flat in the left-right direction.
The present invention may be embodied as a nickel hydride secondary battery as an electricity storage device or an electric double layer capacitor.

  T ... opposing portion, 10 ... secondary battery as power storage device, 11 ... case, 14 ... electrode assembly, 21 ... positive electrode sheet, 21b ... positive electrode active material layer, 22 ... negative electrode sheet, 22b ... negative electrode active material layer, 23 ... separator, 24 ... non-opposing part, 25 ... adhesive tape.

Claims (6)

A positive electrode sheet in which a positive electrode active material layer is formed on at least one surface;
A negative electrode sheet having a negative electrode active material layer formed on at least one surface thereof,
And an electrode assembly configured by laminating a separator interposed between the positive electrode sheet and the negative electrode sheet, a power storage device housed in a case,
The electrode assembly includes an opposing portion including the positive electrode active material layer and the negative electrode active material layer facing the positive electrode active material layer;
A non-facing portion that extends in a direction along the surfaces of the positive electrode active material layer and the negative electrode active material layer from the facing portion, and that is not coated with the positive electrode active material layer and the negative electrode active material layer;
The non-opposing portion is gathered toward at least one of the opposite ends in the stacking direction of the electrode assembly, and the direction perpendicular to the stacking direction of the electrode assembly on the gathered side Projecting in the laminating direction from the end face along
The power storage device according to claim 1, further comprising: an adhesive tape attached to cover at least a tip of the gathered non-opposing portion and attached to the facing portion on the gathered end surface.   2. The power storage device according to claim 1, wherein the non-opposing portions are gathered separately on both end face sides in the stacking direction of the electrode assembly.   The electrical storage according to claim 2, wherein both end portions of the adhesive tape are attached to opposing portions of both end faces in the laminating direction, and the adhesive tape is attached across two non-opposing portions gathered together. apparatus.   The power storage device according to any one of claims 1 to 3, wherein the adhesive tape is attached to a position facing the electrode assembly.   The power storage device according to claim 1, wherein the adhesive tape is attached so as to cover a part of the electrode assembly.   The power storage device according to any one of claims 1 to 5, wherein the power storage device is a secondary battery.