JP6213036B2 - Storage element and method for manufacturing the same - Google Patents

Description

  The present invention relates to a power storage element including a nonaqueous electrolyte secondary battery such as a lithium ion secondary battery.

  An electrode body of a non-aqueous electrolyte secondary battery such as a lithium ion secondary battery described in Patent Document 1 includes a positive electrode body and a negative electrode body that are alternately and repeatedly arranged via a separator. The positive electrode body and the negative electrode body include a conductive base material (conductive sheet) and an active material layer provided on the conductive sheet. Any conductive sheet of the positive electrode body and the negative electrode body is provided with a portion (uncoated portion) where the active material layer is not provided. At both ends of the electrode body, there are provided portions (lead portions) in which the uncoated portions of the positive electrode body and the negative electrode body are laminated. These lead portions are mechanically and electrically connected to positive and negative current collectors, respectively. The current collector is electrically connected to the external terminal.

  The lead portion of the electrode body and the current collector are connected by welding such as ultrasonic welding. However, in the conventional power storage elements including those described in Patent Document 1, the electrical resistance reduction of the welded portion between the electrode body and the current collector has not been sufficiently studied.

JP 2012-124132 A

  This invention makes it a subject to reduce the electrical resistance of the welding part of an electrode body and a collector in an electrical storage element.

This onset Ming, an external terminal, the conductive sheet is formed by laminating with intervening separators, the conductive sheet is the a portion where the active material layer is formed, a region where the active material layer is not provided Not An electrode body having a coating portion and having a lead portion formed by stacking a plurality of uncoated portions of the conductive sheet, and electrically connecting the lead portion of the electrode body and the external terminal current collector and, with the lead portion and the current collector and the welds were connected by welding, the uncoated portion of the plurality of layers constituting the lead portion, the active material than at least the weld Provided is a power storage device including a close contact portion that is in close contact with each other at a position on a layer side .
And in the 1st mode, the above-mentioned close part is constituted by the press-contact part formed by press-contacting the uncoated part of a plurality of layers which constitute the above-mentioned lead part in the lamination direction.
In the second aspect, a compression element that compresses the plurality of uncoated portions constituting the lead portion in the stacking direction is provided, and the close contact portion is formed by stacking the plurality of uncoated portions by the compression element. The compression element includes an insertion hole through which the lead portion is inserted, and the compression portion includes a plurality of uncoated portions that are compressed in the stacking direction by a hole edge of the insertion hole. And the compression element includes a first region that includes the lead portion of the electrode body and includes a portion excluding the lead portion of the electrode body. The partition member is configured to partition the region so as not to allow the electrolyte solution to flow out from the second region to the first region.
In the third to fifth aspects, a crimping element for crimping a plurality of uncoated portions of the plurality of layers constituting the lead portion in a stacking direction is provided, and the close contact portion includes a plurality of layers of the uncoated portions by the crimping element. It is comprised by the crimping part which crimped the coating part in the lamination direction. And in the 3rd aspect, the said crimping element is comprised by the elastic member which pinches | interposes the said uncoated part of multiple layers elastically. In a fourth aspect, the caulking element includes a first member and a second member that are coupled in a fixed state, and the caulking portion includes the first member and the second member. It is formed by being sandwiched between. In a 5th aspect, it has the plate member which pinches | interposes the said uncoated part of the said multiple layers between the said electrical power collectors, The said crimping element is comprised by the said electrical power collector and the said plate member.

  In the intimate portion, a plurality of uncoated portions constituting the lead portion are in intimate contact with each other. In other words, in the intimate portion, a plurality of uncoated portions constituting the lead portion are densely stacked with substantially no gap. The close contact portion is provided at a position closer to the active material layer than the welded portion (inside the welded portion). Therefore, a plurality of uncoated portions constituting the lead portion are densely laminated even in the welded portion. Since the current collector is welded to the lead portion in which the uncoated portions of a plurality of layers are densely stacked in this way, in the welded portion (the portion where the lead portion and the current collector are electrically connected) Electric resistance can be reduced.

Further, the present invention provides a conductive sheet including a portion where an active material layer is formed and an uncoated portion which is a region where the active material layer is not provided, and the conductive sheet is laminated with a separator interposed therebetween. And forming an electrode body including a lead portion in which a plurality of uncoated portions of the conductive sheet overlap, and a close portion in which the uncoated portions of the plurality of layers constituting the lead portion are partially in close contact with each other As a welded portion in which the uncoated portion is press-contacted in the stacking direction, and the lead portion and the current collector are welded at a position opposite to the active material layer with respect to the close contact portion. The manufacturing method of the electrical storage element which forms is provided.

  By providing an intimate part where the uncoated parts of the plurality of layers constituting the lead part of the electrode body are in close contact with each other at a position closer to the active material layer than the weld part, the weld part between the electrode body and the current collector is provided. Electric resistance can be reduced.

1 is an exploded perspective view of a battery according to a first embodiment of the present invention. The typical enlarged view of the connection part of the electrode body and current collector in the battery of FIG. FIG. 2 is a schematic cross-sectional view of a connection portion between an electrode body and a current collector in the battery of FIG. 1. (A), (b), and (c) are the typical enlarged views of the connection part of the electrode body and current collector in the modification of 1st Embodiment. The disassembled perspective view of the battery which concerns on 2nd Embodiment of this invention. The typical enlarged view of the connection part of the electrode body and current collector in the battery of FIG. The front view of an insulating board. FIG. 6 is a schematic cross-sectional view of a connection portion between an electrode body and a current collector in the battery of FIG. 5. The disassembled perspective view of a part of the battery according to the third embodiment of the present invention. An elastic member is shown, (a) is a front view, (b) is a top view, (c) is a side view. The typical enlarged view of the connection part of the electrode body and current collector in the battery of FIG. The alternative of the elastic member of 3rd Embodiment is shown, (a) is a front view, (b) is a top view, (c) is a side view. (A), (b) and (c) are top views which show the shape at the time of the crimping of the alternative of the crimping member of 2nd Embodiment. The perspective view of the battery which concerns on 4th Embodiment of this invention. An elastic member is shown, (a) is a front view, (b) is a top view, (c) is a side view. FIG. 15 is a schematic cross-sectional view taken along line XVI-XVI in FIG. 14. The elastic member of the modification of 4th Embodiment is shown, (a) is a front view, (b) is a top view, (c) is a side view. Sectional drawing similar to FIG. 16 at the time of employ | adopting the elastic member of FIG. The part disassembled perspective view of the battery which concerns on 5th Embodiment of this invention. A crimping member is shown, (a) is a front view, (b) is a top view, (c) is a side view. The schematic enlarged view of the connection part of the electrode body and current collector in the battery of FIG. The typical perspective view which shows the alternative of the crimping member of 5th Embodiment. The alternative of the crimping member of 5th Embodiment is shown, (a) is a front view, (b) is a top view, (c) is a side view. The perspective view of the battery which concerns on 6th Embodiment of this invention. A crimping member is shown, (a) is a front view, (b) is a side view. FIG. 25 is a schematic sectional view taken along line XXVI-XXVI in FIG. 24. The disassembled perspective view of the battery which concerns on 7th Embodiment of this invention. The partial expansion disassembled perspective view of the battery which concerns on 7th Embodiment of this invention. The typical sectional view in the longitudinal direction of the leg of a current collector and a plate member. FIG. 30 is a schematic sectional view taken along line XXX-XXX in FIG. 29. The partial expansion disassembled perspective view of the alternative of 7th Embodiment. The partial expansion disassembled perspective view of the other alternative of 7th Embodiment.

(First embodiment)
1 to 3 show a lithium ion secondary battery 1 (hereinafter simply referred to as a battery 1) according to a first embodiment of the present invention.

  The exterior body 2 of the battery 1 includes a case body 2a and a lid 2b that closes the opening of the case body 2a. In the present embodiment, the exterior body 2 has a flat rectangular parallelepiped appearance. An electrode body 3 is accommodated in the case main body 2a and filled with an electrolytic solution. On the outer surface (upper surface) of the lid 2b, a positive external terminal 4A is disposed on one end side, and a negative external terminal 4B is disposed on the other end side. External terminals 4A and 4B are electrically connected to positive and negative current collectors 7A and 7B through connecting member 5 and rivet 6, respectively. As will be described later, the electrode body 3 is mechanically and electrically connected to the current collectors 7A and 7B. An upper packing 8 made of insulating resin is interposed between the external terminals 4A and 4B and the outer surface of the lid 2b, and is also made of insulating resin between the current collectors 7A and 7B and the inner side surface (lower surface) of the lid 2b. The lower packing 9 is interposed.

  As shown in FIG. 3, the electrode body 3 in the present embodiment includes an elongated strip-shaped positive electrode body 11 </ b> A and a negative electrode body 11 </ b> B, and a separator 10 made of a similarly elongated strip-shaped microporous resin sheet. And arranged alternately and wound into an elliptic cylinder with a high flatness. The electrode body 3 has a structure in which a plurality of layers of a positive electrode body 11A and a negative electrode body 11B are stacked with a separator 10 interposed therebetween.

  Referring to FIG. 3, the negative electrode body 11 </ b> B includes a conductive sheet 12 </ b> B that is a copper foil in the present embodiment, and a negative electrode active material layer 13 </ b> B formed on both surfaces of the conductive sheet 12 </ b> B. The active material layer 13B is provided up to the side edge at one end (left side in FIGS. 1 and 3) in the width direction of the conductive sheet 12B, but the other in the width direction of the conductive sheet 12B (FIGS. 1 and 3). 3 is provided with an uncoated portion 14B in which the conductive sheet 12B is exposed without providing the active material layer 13B. Similarly, the positive electrode body 11A includes a conductive sheet 12A, which is an aluminum foil in this embodiment, and a positive electrode active material layer 13A formed on both surfaces of the conductive sheet 12A. 3A is provided with an uncoated portion 14A in which the conductive sheet 12A is exposed without providing the active material layer 13A.

  Referring to FIGS. 1 and 3, a negative electrode lead portion 16 </ b> B having an elongated elliptical cylindrical shape protrudes from one end (right side in these drawings) of the electrode body 3. The lead portion 16B is formed by overlapping a plurality of uncoated portions 14B of the negative electrode negative electrode body 11B. Similarly, from the other end (left side in these drawings) of the electrode body 3, an elongated elliptical cylindrical positive electrode lead portion 16 </ b> A formed by overlapping a plurality of uncoated portions 14 </ b> A of the positive electrode body 11 </ b> A protrudes. ing.

  The positive and negative current collectors 7A and 7B include a base portion 7a electrically connected to the external terminals 4A and 4B, respectively, and a pair of leg portions 7b and 7b each having a constant width and projecting downward from the base portion 7a. Is provided. The leg portions 7b and 7b of the negative electrode current collector 7B are mechanically and electrically connected to the negative electrode lead portion 16B of the electrode body 3B. Similarly, the leg portions 7b and 7b of the positive electrode current collector 7A are mechanically and electrically connected to the positive electrode lead portion 16A of the electrode body 3A. In the present embodiment, the negative electrode current collector 7B is made of copper, and the positive electrode current collector 7A is made of aluminum.

  Hereinafter, the connection structure between the lead portion 16B of the electrode body 3 and the leg portion 7b of the current collector 7B will be described taking the negative electrode side as an example. Also on the positive electrode side, the lead portion 16A of the electrode body 3 and the leg portion 7b of the current collector 7A are connected with the same structure. This also applies to the second to seventh embodiments described later.

  Referring to FIGS. 1 and 2, the leg 7b of the current collector 7B is disposed outside the elliptical lead portion 16B, and is the outermost layer among the uncoated portions 14B of the plurality of layers constituting the lead portion 16B. It is in contact with the uncoated part 14B. As shown most clearly in FIG. 2, a welded portion 17 and a pressure contact portion (close contact portion) 18 are provided on the tip end side of the leg portion 7b.

  Referring also to FIG. 3, in the welded portion 17, a plurality of uncoated portions 14B in the vicinity of the surface (inner surface) of the lead portion 16B on the leg portion 7b side are welded to the leg portion 7b. Examples of a method for forming the welded portion 17 by welding the lead portion 16B and the leg portion 7b include resistance welding such as ultrasonic welding and spot welding, laser welding, and the like. As shown in FIG. 2, in the present embodiment, the shape of the welded portion 17 when the leg portion 7 b is viewed from the side is a relatively long and narrow elliptical shape whose long axis extends along the leg portion 7 b. However, the shape of the welded portion 17 and the specific method of welding are not particularly limited as long as necessary mechanical strength can be ensured and no problem occurs in terms of electrical resistance.

  As most clearly shown in FIG. 1, the press contact portion 18 is provided at a position near the center of the electrode body 3 in the direction opposite to the positive and negative lead portions 16 </ b> A and 16 </ b> B with respect to the weld portion 17 (left and right direction in FIG. 1). Yes. In other words, the press contact portion 18 is provided at a position closer to the active material layer 13B than the weld portion 17. In the present embodiment, the press-contact portion 18 is provided with a space inside the electrode body 3 with respect to the welded portion 17. However, the pressure contact portion 18 may be provided close to the welded portion 17. Further, a part or all of the portion of the press contact portion 18 on the welded portion 17 side may contact the welded portion 17. As shown in FIG. 3, in the press contact portion 18, a plurality of uncoated portions 14B in the vicinity of the inner surface of the lead portion 16B are pressed against the leg portion 7b by, for example, cold press contact.

  As shown in FIG. 2, the shape seen from the side of the leg 7b of the press-contact part 18 in this embodiment is a narrow strip extending in the direction parallel to the long axis of the welded part 17 or in the longitudinal direction of the leg 7b. Or the linear center part 18a and a pair of narrow side part 18b, 18b extended toward the welding part 17 from the both ends of this center part 18a are provided. In the present embodiment, the side portions 18b and 18b extend obliquely with respect to the direction perpendicular to the long axis of the welded portion 17 or the longitudinal direction of the leg portion 7b. Further, the length L1 (the distance from the tip of one side portion 18b to the tip of the other side portion 18b) in the major axis direction of the welded portion 17 is greater than the length L2 of the welded portion 17 in this direction. Is also set longer.

  In the press contact part 18, the uncoated parts 14B of a plurality of layers constituting the lead part 16B are in close contact with each other. In other words, in the press-contact portion 18, a plurality of uncoated portions 14B constituting the lead portion 16B are densely stacked with substantially no gap. As described above, the press contact portion 18 is provided at a position closer to the center in the opposing direction of the lead portion 16B than the weld portion 17. In other words, the press contact portion 18 is provided at a position closer to the active material layer 13B than the weld portion 17. In short, the press contact part 18 is provided inside the welded part. Therefore, in the welded portion 17, a plurality of uncoated portions 14B constituting the lead portion 16B are densely stacked. Since the current collectors 7A and 7B are welded to the lead portion 16B in which the plurality of uncoated portions 14B are densely stacked as described above, the electrical resistance in the welded portion 17 can be reduced. The performance of the battery 1 is improved by reducing the electric resistance in the welded portion 17.

  As described above, the length L1 of the pressure contact portion 18 is longer than the length L2 of the welded portion 17. Therefore, in the welded portion 17, the multiple uncoated portions 14 </ b> B constituting the lead portion 16 </ b> B are securely in contact with each other in the entire length L <b> 2, and the electrical resistance in the welded portion 17 is reliably reduced.

  Since it is not necessary to add a special member or part to provide the press-contact part 18, it is possible to reduce the electric resistance in the welded part 17 without increasing the number of parts.

  Next, a method for manufacturing the battery 1 of the present embodiment will be described.

  In the manufacture of the electrode body 3, the positive electrode body 11 </ b> A and the negative electrode body 11 </ b> B, both of which are band-shaped, are alternately arranged with the same band-shaped separator 10 interposed therebetween, and are wound into an elliptic cylinder. At the time of winding, the side edge of the positive electrode body 11A (uncoated part 14A side) is positioned outside the one side edge of the separator 10 in the width direction, and the negative electrode is positioned more negative than the other side edge of the separator 10 in the width direction. The side edge (uncoated part 14B side) of the body 11B is positioned outside. In this way, the lead portions 16A and 16B are formed by shifting the positions of the positive electrode body 11A and the negative electrode body 11B in the width direction with respect to the separator 10.

  The external terminals 4A and 4B, the connection member 5, the rivet 6, the upper and lower packings 8 and 9 and the positive and negative current collectors 7A and 7B are assembled to the lid 2b in a separate process from the manufacturing of the electrode body 3. It is done.

  Next, the positive and negative lead portions 16A and 16B of the electrode body 3 are mechanically and electrically connected to the leg portions 7b of the positive and negative current collectors 7A and 7B. Hereinafter, taking the negative electrode side as an example, a procedure for connecting the lead portion 16B to the leg portion 7b of the current collector 7B will be described. The leg portion 7b of the positive current collector 7A and the lead portion 16A are also connected in the same procedure. This also applies to the second to seventh embodiments described later.

  Referring to FIGS. 1 to 3, first, the leg portion 7 b of the current collector 7 </ b> B is disposed outside the side portion of the elliptical cylindrical lead portion 16. With this arrangement, the innermost surface of the leg portion 7b and the uncoated portion 14B of the outermost layer among the plurality of uncoated portions 14B constituting the lead portion 16B come into contact with each other. Next, the pressure contact portion 18 is formed by, for example, cold pressure welding. After the press contact portion 18 is formed, the active material layers 13A and 13B are positioned on the outer side in the facing direction (left and right direction in FIG. 1) of the lead portions 16A and 16B that are more positive than the press contact portion 18, that is, the press contact portion 18. Is welded to the lead portion 16B and the leg portion 7b of the current collector 7B to form a welded portion 17 at a position on the opposite side. By forming the press contact portion 18, a plurality of uncoated portions 14B are densely laminated in advance without gaps in the inner portion of the lead portion 16B than the welded portion 17, and accordingly, the lead portion 16B Even in the portion where the welded portion 17 is formed, the plurality of uncoated portions 14 </ b> B are in a state of being closely stacked. By performing welding in this state, the uncoated portion 14B and the leg portion 7b constituting the lead portion 16B are sufficiently melted together to obtain a good welded portion 17B. As a result, as described above, the electrical resistance in the welded portion 17 can be reduced and the performance of the battery 1 can be improved.

  When the weld 17 is formed by resistance welding or laser welding, spatter occurs. Moreover, when forming the welding part 17 by ultrasonic welding, dust will generate | occur | produce. Spatter and dust (fine metal pieces) are mixed in the electrolyte and move into the battery 1.

  In this embodiment, since the conductive sheet 12 of the negative electrode body 11B is made of copper, a minute copper piece is generated when the negative electrode side lead portion 16B and the welded portion 17 of the leg portion 7b of the current collector 7B are formed. When this minute copper piece moves to the lead portion 16A of the positive electrode and comes into contact with the uncoated portion 14A of the conductive sheet 12A made of aluminum, the minute copper piece is deposited in the electrolyte as copper ions. When the eluted copper ions reach the negative electrode body 11B, they are deposited on the surface of the negative electrode body 11B. When this deposition amount increases, the deposited copper breaks through the separator 10, reaches the positive electrode body 11A side, and a micro short circuit is formed. As a result, a current flows through the micro short circuit to locally generate heat, and the separator 10 is melted to form a minute through hole, which may cause a reduction in the capacity of the battery 1. However, in this embodiment, since the press contact portion 18 is provided on the inner side of the welded portion 17, it is possible to prevent the minute copper piece generated when forming the welded portion 17 on the negative electrode side from moving to the lead portion 16A of the positive electrode. . By preventing movement to the lead portion 16A of the positive electrode, it is possible to prevent electrochemical dissolution of the minute copper piece, and thus it is possible to prevent a decrease in capacity of the battery 1 due to the minute copper piece. In particular, in this embodiment, the pressure contact portion 18 extends obliquely from both ends of the center portion 18a to the upper and lower end portions of the weld portion 17 in addition to the center portion 18a extending in the longitudinal direction of the leg portion 7b inside the weld portion 17. Side portions 18b, 18b are provided. By making the pressure contact portion 18 into such a shape, it is possible to more reliably prevent the minute copper piece generated when the welded portion 17 is formed from moving toward the lead portion 18 of the positive electrode.

  4A to 4C show modified examples of the shape of the pressure contact portion 18 when the leg portion 7b is viewed from the side. In the example of FIG. 4A, the side portions 18b and 18b extend in a direction substantially perpendicular to the major axis of the pressure contact portion 18 of the leg portion 7b or in the width direction of the leg portion 7b. In the example of FIG. 4B, the shape of the pressure contact portion 18 is a rectangular shape that surrounds the entire circumference of the welded portion 17 with an interval therebetween. In the example of FIG. 4C, the press contact portion 18 has only a linear portion extending in the longitudinal direction of the leg portion 7b. Also in these modified examples, the press contact portion 18 may be provided close to the weld portion 17, or a part or all of the portion of the press contact portion 18 on the weld portion 17 side may be in contact with the weld portion 17.

Second Embodiment FIGS. 5 to 8 show a battery 1 according to a second embodiment of the present invention. The battery 1 of this embodiment includes a metal clip 21 that sandwiches and covers the lead portions 16A and 16B and the leg portions 7b of the current collectors 7A and 7B at the welded portion 17 (see FIG. 8).

  As shown most clearly in FIGS. 5 and 6, the pressure is applied to a position inside the electrode body 3 relative to the leg portion 7b, and thus a position inside the electrode body 3 relative to the welded portion 17 (position on the active material layer 13B side). A partition plate (partition member) 22 as an element is arranged. The partition plate 22 in the present embodiment is made of an insulating material, but the partition plate 22 may be one in which an insulating material is applied to the entire surface of a member having a certain degree of conductivity.

  As shown most clearly in FIG. 7, the partition plate 22 is provided with an insertion hole 22 a having a constant width that penetrates in the plate thickness direction. That is, the partition plate 22 includes an elliptical first member 22c and a second member 22d in which an elliptical through-hole having a size larger than the outline of the first portion 22c is formed. The insertion hole 22a has an elongated oval shape corresponding to the end surface shape of the lead portion 16B of the electrode body 3. The width of the insertion hole 22a is set to be smaller than the thickness (a state in which no external force is applied) of the plurality of uncoated portions 14B in the lead portion 16B. Therefore, in the portion inserted through the insertion hole 22a of the lead portion 16B, the uncoated portion 14B is compressed in the stacking direction by the hole edge 22b of the insertion hole 22a, whereby a compression portion (close contact portion) 23 is formed. Yes.

  The formation of the welded portion 17 between the leg portion 7b of the current collector 7B and the lead portion 16B is performed by inserting the lead portion 16B into the insertion hole 22a of the partition plate 22 in advance, that is, by pressing with the hole edge 22b of the insertion hole 22a. It is executed after forming the part 23.

  By providing the compression part 23, the uncoated part 14B of a plurality of layers is in a state of being densely laminated in advance without gaps in the part inside the welded part 17 of the lead part 16B, and the part that forms the welded part 17 However, the plurality of uncoated parts 14B are densely stacked on each other. As a result, a good welded portion 17B is obtained, and the electrical resistance at the welded portion 17 can be reduced. Further, by forming the pressing portion 23 by the partition plate 22 disposed inside the battery 1 rather than the negative-side welded portion 17, it is possible to prevent the movement of the fine copper piece generated during welding to the positive electrode side.

  The interior of the exterior body 2 (the case main body 2a and the lid 2b) is partitioned into two regions by the partition plate 22. One region is a region outside the positive and negative partition plates 22 (regions on both ends of the electrode body 3 in the opposing direction of the positive and negative lead portions 16A and 16B or the dielectric layer 13A of the electrode body 3, 13B side area) (first area). Lead portions 16A and 16B are arranged in this region. The other region is a region sandwiched between the positive electrode side and negative electrode side partition plates 22, in other words, an outer region of the electrode body with respect to the dielectric layers 13A and 13B (second region). This region includes a portion of the electrode body 3 excluding the lead portions 16A and 16B, that is, a portion where the active material layers 13A and 13B of the positive electrode body 11A and the negative electrode body 11B are provided. Since the portion inserted into the insertion hole 22a of the lead portions 16A and 16B is the compression portion 23 compressed by the hole edge 22b, the passage of the electrolyte does not substantially occur in the portion of the insertion hole 22a. That is, the electrolyte does not flow out from the second region sandwiched between the positive electrode side and the negative electrode side partition plate 22 by the partition plate 22 to the first region outside the second region. Therefore, the electrolytic solution can be filled only in the second region, that is, the portion where the active material layers 13A and 13B of the positive electrode body 11A and the negative electrode body 11B are formed in the internal space of the exterior body 2. Therefore, by providing the partition plate 22, the amount of the electrolytic solution that needs to be filled in the exterior body 2 can be reduced.

  Other configurations and operations of the second embodiment are the same as those of the first embodiment.

(Third embodiment)
The battery 1 according to the third embodiment of the present invention shown in FIGS. 9 to 11 includes an elastic member 24 as a caulking element and a clip 21 similar to that of the second embodiment. The elastic member 24 in the present embodiment is formed by bending a metal wire having elasticity, and a pair of pressure parts 24a and 24a that elastically sandwich the lead part 16B from both sides in the stacking direction of the uncoated part 14B, A pair of connecting portions 24b and 24b for connecting both ends of the pressurizing portions 24a and 24a are provided. The pressurizing parts 24a, 24a are a first part 24c arranged so as to extend in the long axis direction of the elliptical welded part 17 or the longitudinal direction of the leg part 7b, and the welded part 17 from both ends of the first part 24c. And a second portion 24d arranged so as to extend in a direction orthogonal to the major axis of the leg portion 7 or in the width direction of the leg portion 7b. By being elastically sandwiched between the pair of pressurizing parts 24a, 24a, the center part of the electrode body 3 (position on the active material layer 13B side) and the welded part 17 with respect to the welded part 17 of the lead part 16B. At the positions on both sides in the longitudinal direction of the leg portion 7b, a crimped portion (close contact portion) 25 is formed by crimping a plurality of uncoated portions 14B in the stacking direction.

  Formation of the leg portion 7b of the current collector 7B and the welded portion 17 of the lead portion 16B is performed by attaching the elastic member 24 to the lead portion 16B in advance, that is, by elastic pressing by the pressing portion 24a of the elastic member 24. This is performed after the fastening portion 25 is formed.

  A portion formed by the first portion 24 c of the pressurizing portion 24 a in the crimping portion 25 is located in a portion inside the welded portion 17. Therefore, a plurality of uncoated portions 14B are densely stacked in advance without gaps in the inner portion (active material layer 13B side) of the welded portion 17, and even in the portion where the welded portion 17 is formed, a plurality of layers are formed. The uncoated portions 14B are densely stacked on each other. As a result, a good welded portion 17B is obtained, and the electrical resistance at the welded portion 17B can be reduced. Further, by forming the crimped portion 25 inside the battery 1 rather than the welded portion 17 on the negative electrode side, it is possible to prevent the movement of the minute copper piece generated during welding to the positive electrode side.

  Other configurations and operations of the third embodiment are the same as those of the first embodiment.

  FIG.12 and FIG.13 shows the alternative of the elastic member 24 (caulking element) of 3rd Embodiment. The elastic member 24 connects a pair of pressure parts 124 and 125 that elastically sandwich the uncoated part 14B constituting the lead part 16B (for example, see FIG. 9), and both ends of the pressure parts 124 and 125. And a pair of connecting portions 126, 127. Each pressurizing part 124, 125 includes first parts 124a, 125a arranged so as to extend in the long axis direction of the welded part 17 or the longitudinal direction of the leg part 7b, and both ends of the first parts 124a, 125a. A pair of second portions 124b and 125b arranged to extend in a direction orthogonal to the long axis of the welded portion 17 or in the width direction of the leg portion 7b. The length of the first portion 125a of one pressing part 125 is set shorter than the length of the first part 124a of the other pressing part 124. Therefore, when viewed from the front (see FIG. 12A), the pressurizing unit 125 having the short first portion 125a is spaced apart from the pressurizing unit 124 having the long first portion 124a. positioned. Each of the connecting portions 126 and 127 includes a pair of first portions 126a and 127a extending outward from the end portions of the pressurizing portions 124 and 125, respectively, and an obliquely extending first connecting the end portions of the first portions 126a and 127a. And two portions 126b and 127b. Between the pressurization parts 124 and 125, it is not provided on the same plane, but is provided between the surfaces which separated the space | interval B.

  By being elastically sandwiched between the pair of pressure parts 124 and 125, a crimped part is formed by crimping a plurality of uncoated parts 14B in the stacking direction. First, the caulking portion 25a (see FIG. 11) is formed at a position near the center of the electrode body 3 with respect to the welded portion 17 of the lead portion 16B by the first portions 124a and 125a of the pressurizing portions 124 and 125. Further, the second portions 124b and 125b of the pressurizing portions 124 and 125 are positioned on both sides in the longitudinal direction of the leg portion 7b of the current collector 7B with respect to the welded portion 17 of the lead portion 16B, and the crimping portion 25b (FIG. 11). Reference) is formed.

  As shown in FIG. 12C, the pressurizing unit 124 and the pressurizing unit 125 face each other with a gap B before caulking. At the time of caulking, the elastic member 24 is deformed to eliminate the interval B between the pressurizing parts 124 and 125 as shown in FIGS. 16B is sandwiched elastically. As described above, since one pressing part 125 is located inside the other pressing part 124, the lead part 16B (uncoated part 14B) sandwiched between the pressing parts 124, 125 is In addition to being pressurized in the stacking direction of the uncoated portion 14B, it is curved or bent. As a result, in the crimping portions 124 and 125, the uncoated portion 14B is more firmly and tightly crimped, and the electrical resistance in the welded portion 17 is reduced, and the minute copper pieces generated during welding toward the positive electrode side. The movement prevention can be realized more effectively.

  In order to sufficiently bend or bend the lead portion 16B (uncoated portion 14B), as shown in FIG. 13A, when viewed from the side (the short side surface of the exterior body 2 shown in FIG. 1), the lead portion 16B (uncoated portion 14B) is It is preferable to deform the elastic member 24 to such an extent that the pressure parts 124 and 125 overlap each other. As shown in FIG. 13B, the degree of bending or bending of the lead portion 16B can be increased by increasing the overlapping amount of the pressure portions 124 and 125. As shown in FIG. 13C, the degree of bending or bending of the lead portion 16B is further increased by deforming the elastic member 24 until the positions of the pressurizing portions 124, 125 are replaced with those before deformation (see FIG. 12). Can be increased. By deforming the elastic member 24 as shown in FIGS. 13A to 13C, the bending amount or bending amount of the lead portion 16B becomes equal to or greater than the thickness of the lead portion 16B, and the uncoated portion 14B becomes stronger and denser. It will be in a crimped state.

  Any one of the pressure parts 124 and 125 having the first portions 124a and 125a having different lengths may be disposed on the outer peripheral surface of the lead part 16B, and any of them may be disposed on the inner peripheral surface of the lead part 16B. When the welded portion 17 is formed by ultrasonic welding, the inner portion of the lead portion 16B has a short first portion 125a on the side where the end surface of the horn of the ultrasonic welder abuts (the side on which vibration is applied). It is preferable to arrange the pressure part 125. When the elastic member 24 is attached to the lead portion 16B in such a posture, the pressure portion 125 having the short first portion 125a moves elastically toward the pressure portion 124 having the long first portion 124a. The tension acting on the uncoated layer 14B is relieved by the vibration. As a result, it is possible to prevent the uncoated portion 14B (the conductive sheet 12B, which is a copper foil in the present embodiment) constituting the lead portion 16B from being damaged due to vibration during ultrasonic welding.

(Fourth embodiment)
The battery 1 according to the fourth embodiment of the present invention shown in FIGS. 14 to 16 has a crimped portion 25 formed of an elastic member 28 having a structure different from that of the third embodiment. Specifically, the elastic member 28 in the present embodiment is formed by punching and bending a metal plate material having elasticity, and a pair of pressurizing parts 28a, 28a having a constant width, and these pressurizing parts 28a, And a rectangular connecting portion 28b for connecting 28a. The pressurizing parts 28a, 28a are first and second parts 28c, 28d arranged in parallel at a distance so as to extend in the long axis direction of the elliptical welded part 17 or in the longitudinal direction of the leg part 7b, A pair of third portions connected to both ends of the first and second portions 28c and 28d and arranged to extend in a direction orthogonal to the long axis of the welded portion 17 or in the width direction of the leg portion 7b. 28e, 28e.

  A wire rod 28f having a circular cross section is attached to the inside of the first to third portions 28c to 28e of each pressurizing portion 28a to form a protrusion. As shown in FIG. 15, the wire 28f has a rectangular frame shape.

  A crimped portion (close contact portion) in which a plurality of uncoated portions 14B are crimped in the stacking direction so as to surround the welded portion 17 of the lead portion 16B by being elastically sandwiched between the pair of pressurizing portions 28a, 28a. ) 25 is formed. Since the wire rod 28f provided inside the pressurizing portions 28a and 28a contacts the uncoated portion 14B of the lead portion 16B in a line contact manner, a sufficiently strong tightening force acts on the uncoated portion 14B. Thus, the caulking portion 25 having sufficient strength is formed. In the present embodiment, the pressurizing portions 28a, 28a surround the welded portion 17 of the lead portion 16B with a space therebetween, so that the crimping portion 25 is also formed to surround the welded portion 17 with a space therebetween. However, the crimping portion 25 may be provided close to the welded portion 17, or a part or all of the crimped portion 25 on the welded portion 17 side may be in contact with the welded portion 17.

  Formation of the leg portion 7b of the current collector 7B and the welded portion 17 of the lead portion 16B is performed by attaching the elastic member 28 to the lead portion 16B in advance, that is, by elastic pressing by the pressing portion 28a of the elastic member 28. This is performed after the fastening portion 25 is formed.

  A portion formed by the first portion 28 c of the pressurizing portion 28 a in the crimping portion 25 is located in a portion inside the welded portion 17. Therefore, a plurality of uncoated portions 14B of a plurality of layers are in a state of being densely stacked in advance without gaps in a portion inside the welded portion 17, and a plurality of uncoated portions 14B of a plurality of layers are formed even in a portion forming the welded portion 17. They are stacked closely together. As a result, a good welded portion 17B is obtained, and the electrical resistance at the welded portion 17 can be reduced. Further, by forming the crimped portion 25 inside the battery 1 rather than the welded portion 17 on the negative electrode side, it is possible to prevent the movement of the minute copper piece generated during welding to the positive electrode side. In particular, since the caulking portion 25 surrounds the entire circumference of the welded portion 17, the movement of the minute copper piece to the positive electrode side can be more reliably prevented.

  Other configurations and operations of the fourth embodiment are the same as those of the first embodiment.

  FIG.17 and FIG.18 shows the modification of the elastic member 28 of 4th Embodiment. In this elastic member 28, instead of providing the wire rod 28f (for example, see FIG. 16), the first to third portions 28c to 28e of the pressurizing portion 28a are bent inward to provide the ridge portion 28g. Since the ridge portion 28g is in line contact with the uncoated portion 14B of the lead portion 16B, a sufficiently strong clamping force acts on the uncoated portion 14B, and the swaged portion has sufficient strength. 25 is formed.

(Fifth embodiment)
19 to 21 show a battery 1 according to a fifth embodiment of the present invention. The battery 1 includes a substantially rigid caulking tool (caulking element) 31. The crimping tool 31 includes a pair of halves 32A and 32B that are brought into contact with each other and connected in a fixed state. The individual halves 32A and 32B have bottom walls 32a and side walls 32b, 32c protruding from portions other than the portions facing each other when the halves 32A and 32B of the peripheral edge of the bottom wall 32a are connected. 32d. The side wall parts 32b and 32c are arrange | positioned facing, and are connected by the side wall part 32d. Referring to FIG. 20, when the half portions 32 </ b> A and 32 </ b> B are connected, a bottom portion 31 a of the crimping tool 31 is formed by the bottom wall portion 32 a, and a crimping tool 31 having a rectangular shape rounded by the side wall portions 32 b to 32 d. Frame wall portion 31b is formed. When the half portions 32A and 32B are connected by the notches 32e and 32f provided in the side wall portions 32b and 32c of the half portions 32A and 32B, a pair of slits 31c and 31d are formed in the frame wall portion 31b. Similarly, when the half portions 32A and 32B are connected by the notches 32g provided in the bottom wall portions 32a of the half portions 32A and 32B, a slit 31e is formed in the bottom portion 31a. In the present embodiment, all of the slits 31c to 31e are linear. The slits 31c to 31e are arranged in a straight line, and the slits 31c and 31d are connected to the slit 31e to form one slit.

  As shown most clearly in FIG. 19, the crimping tool 31 is attached to the lead portion 16B so as to be elastically sandwiched from both sides in the stacking direction of the uncoated portion 14B. Specifically, one half portion 32A contacts the outermost uncoated portion 14B of the lead portion 16B, and the other half portion 32B contacts the innermost uncoated portion 14B of the lead portion 16B. In the state, the halves 32A and 32B are butted together and connected in a fixed state. When the crimping tool 31 is attached to the lead portion 16B, the pair of slits 31c and 31d formed in the frame wall portion 31b is directed from the tip end side of the lead portion 16B toward the center side (active material layer 13B side) of the electrode body 3. The slit 31e formed in the bottom wall portion 32a extends in a direction parallel to the long axis of the welded portion 17 or in the longitudinal direction of the leg portion 7b. When the caulking tool 31 is attached to the lead portion 16B, a caulking portion (close contact portion) 25 is formed by caulking a plurality of uncoated portions 14B in the stacking direction by the edges of the slits 31c to 31e.

  As shown most clearly in FIG. 21, the shape of the caulking portion 25 in the present embodiment when viewed from the side of the leg portion 7b is a direction parallel to the long axis of the welded portion 17 or the length of the leg portion 7b. A narrow strip or straight central portion 25a extending in the direction and a pair of narrow strip side portions 25b and 25b extending from both ends of the central portion 25a toward the welded portion 17 are provided. The central portion 25a is disposed on the inner side with a gap with respect to the welded portion 17, and the side portions 25b and 25b are disposed with an interval above and below the welded portion 17 in the drawing. The crimping portion 25 may be provided close to the welded portion 17, or a part or all of the portion on the welded portion 17 side of the press contact portion 18 may be in contact with the welded portion 17.

  The current collectors 7A and 7B in this embodiment include a bent portion 7c at the tip of the leg portion 7b. The bent portion 7c is inserted into a gap between the frame wall portion 31b of the caulking tool 31 attached to the lead portion 16B and the lead portion 16B, and comes into contact with the uncoated portion 14B of the outermost layer of the lead portion 16B. The In this state, the lead portion 16B and the bent portion 7c are welded to form the welded portion 17.

  Since the crimped portion 25 is provided, the uncoated portion 14B having a plurality of layers is densely laminated in advance at a portion inside the welded portion 17 of the lead portion 16B, so that the electric resistance is low. A good weld 17B is obtained. In addition, by providing the crimping portion 25 including the central portion 25a disposed closer to the inner side than the welded portion 17, it is possible to prevent the movement of the minute copper piece generated during welding to the positive electrode side.

  The caulking portion 31 can be formed by connecting the half portions 32A and 32B so as to sandwich the lead portion 16B. Therefore, workability is good for the work of forming the crimped portion 31.

  Other configurations and operations of the fifth embodiment are the same as those of the first embodiment.

  22 and 23 show alternatives of the caulking tool (caulking element) 31 of the fifth embodiment. In this alternative, the pair of slits 31c and 31d formed in the frame wall portion 31b and the slit 31e formed in the bottom portion 31a are both broken lines.

  The shape of the slits 31c to 31e will be described by taking as an example a state in which the crimping tool 31 is mounted on the lead portion 16B (see FIG. 19). First, the slits 31c and 31d of the frame wall portion 31b include a linear first portion 31f extending from the distal end side of the lead portion 16B toward the center side (active material layer 13B side) of the electrode body 3. The slits 31c and 31d are directed from the leading end side of the lead portion 16B toward the center side of the electrode body 3 at a position shifted in the stacking direction of the uncoated layer 14B constituting the slit portion 16B with respect to the first portion 31f. The linear 2nd part 31g extended is provided. Furthermore, the slits 31c and 31d include a third portion 31h that extends obliquely with respect to the first portion 31f and the second portion 31g.

  Next, the slit 31e of the bottom wall portion 32a is formed in the vertical direction in the drawing along the center in the width direction of the caulking tool 31 (in a state where the caulking tool 31 is attached to the lead portion 16B, In the drawing, the first portion 31i extending in the parallel direction or the longitudinal direction of the leg portion 7b, the pair of second portions 31j and 31j extending obliquely from both ends of the first portion 31i, and the second portions 31j and 31j respectively. A pair of third portions 31k, 31k extending in parallel with the first portion 31i in the vertical direction is provided.

  Since the slits 31c to 31e are formed in a polygonal line shape, when the crimping tool 31 is attached to the lead portion 16B, the uncoated portion 14B constituting the lead portion 16B is not only pressed in the stacking direction, but also the slits 31c to 31e. It bends or bends according to the shape. As a result, in the caulking portions 25a and 25b formed by the caulking tool 31, the uncoated portion 14B is more strongly and densely caulked, and electric resistance is reduced in the welded portion 17B and occurs during welding. The prevention of the movement of the minute copper piece to the positive electrode side can be realized more effectively.

  Of the slits 31c to 31e, only the slits 31c and 31d of the frame wall portion 31b may be formed in a polygonal line shape. Conversely, only the slit 31e of the bottom wall portion 32a may be formed in a polygonal line shape.

(Sixth embodiment)
24 to 26 show a battery 1 according to a sixth embodiment of the present invention. The caulking tool (caulking element) 33 provided in the battery 1 includes a pair of fitting members 34A and 34B that are fitted in a state where a plurality of uncoated parts 14B constituting the lead part 16B are sandwiched. As most clearly shown in FIG. 25, these fitting members 34A and 34B are rounded chamfered rectangular frame shapes, and the cross-sectional shape is a flat portion 34a and an edge portion 34b extending obliquely from both ends of the flat portion 34a. , 34b. With this cross-sectional shape, a convex portion 34c is formed on one surface side of the fitting members 34A and 34B, and a concave portion 34d is formed on the other surface side.

  As most clearly shown in FIG. 26, the crimping tool 33 is attached to the lead portion 16B so as to be elastically sandwiched from both sides in the stacking direction of the uncoated portion 14B. Specifically, one fitting member 34A is disposed on the outermost uncoated portion 14B of the lead portion 16B, and the other fitting member 34B is disposed on the innermost uncoated portion 14B of the lead portion 16B. Be placed. Further, the convex portion 34c of one fitting member 34A is elastically fitted into the concave portion 34d of the other fitting portion 34B with the plurality of uncoated portions 14B constituting the lead portion 16B interposed therebetween. It is. By pressing the fitting members 34A and 34B between the concave portions 34c and the convex portions 34d and compressing them, a crimped portion (close contact portion) 25 is formed by crimping a plurality of uncoated portions 14B in the stacking direction. . The shape of the caulking portion 25 in the present embodiment when viewed from the side of the leg portion 7b is a rectangular shape that surrounds the entire welded portion 17 with an interval.

  Formation of the leg portion 7b of the current collector 7B and the welded portion 17 of the lead portion 16B is performed after the crimping tool 33 is mounted on the lead portion 16B in advance, that is, with the fitting members 34A and 34B constituting the crimping tool 33. It is executed after forming the crimping portion 33 by sandwiching and compressing the portion 16B.

  Since the crimped portion 25 is provided, the uncoated portion 14B having a plurality of layers is densely laminated in advance at a portion inside the welded portion 17 of the lead portion 16B, so that the electric resistance is low. A good weld 17B is obtained. Moreover, the movement to the positive electrode side of the small copper piece which generate | occur | produces at the time of welding can be prevented by providing the crimping part 25 surrounding the welding part 17. FIG. The crimping portion 25 may be provided close to the welded portion 17, or a part or all of the crimped portion 25 on the welded portion 17 side may be in contact with the welded portion 17.

  Other configurations and operations of the sixth embodiment are the same as those of the first embodiment.

(Seventh embodiment)
27 to 30 show a battery 1 according to a seventh embodiment of the present invention. The battery 1 includes a plate member 41 disposed so as to sandwich a plurality of uncoated portions 14B constituting the lead portion 16B between the legs 7b of the current collector 7B. As will be described later, caulking portions 42a, 42b, and 42c are formed by the plate member 41 and the leg portion 7b of the current collector 7B. In other words, in this embodiment, the plate member 41 and the leg 7b of the current collector 7B constitute a caulking element. In the present embodiment, the leg portion 7b of the current collector 7B is disposed on the outermost uncoated portion 14B of the lead portion 16B, and the plate member 41 is disposed on the innermost uncoated portion 14B of the lead portion 16B. . The plate member 41 is provided with a bulging portion 43 that bulges in a direction from the outermost layer to the innermost layer of the lead portion 16B. The bulging portion 43 is provided with an opening 43a on one side portion (right side portion in FIG. 28) of the leg portion 7b of the current collector 7B. A bulging portion 44 having a similar shape is also provided on the leg portion 7b of the current collector 7B. The bulging portion 44 also bulges in the direction from the outermost layer to the innermost layer of the lead portion 16B, and an opening 44a is provided on one side portion (right side portion in FIG. 28) of the leg portion 7b.

  As shown most clearly in FIGS. 29 and 30, the space formed inside the bulging portion 43 of the plate member 41 is in a state where a plurality of uncoated portions 14B constituting the lead portion 16B are interposed. Thus, the bulging portion 43 of the leg portion 7a of the current collector 7B is fitted.

  A welded portion 17 is formed by welding the lead portion 16B (uncoated portion 14B) to the leg portion 7b of the current collector 7B at the top wall portions 43b, 44b of the bulging portions 43, 44. On the other hand, around the bulging part 43, the leg part 7b of the current collector 7B and the plate member 41 are caulked together with the lead part 16B (uncoated part 14B) between them, so that the caulking parts 42a to 42c. 42c is formed. The caulking portion 42a is formed at a position closer to the center of the electrode body 3 (position on the active material layer 13B side) than the bulging portions 43 and 44 where the welded portion 17 is formed. The caulking portions 42b and 42c are arranged on both sides (upper and lower sides in the drawing) in the longitudinal direction of the leg portion 7b with respect to the bulging portions 43 and 44 where the welded portion 17 is formed. The welded portion 17 is formed after the formation of these crimping portions 42a to 42c.

  Since the crimped portions 42a to 42c are provided so as to surround the welded portion 17 and the uncoated portion 14B is in close contact with each other, the uncoated portion 14B constituting the lead portion 16B is also densely laminated in the welded portion 17, The electric resistance in the welded portion 17 can be reduced. Further, by providing the crimping portions 42a to 42c, it is possible to prevent the movement of the fine copper piece generated when the welded portion 17 is formed to the lead portion 16A of the positive electrode.

  As shown in FIG. 29 and FIG. 30, by providing the bulging portions 43 and 44, the lead portion 16B (uncoated portion 14B) sandwiched between the plate member 41 and the leg portion 7b of the current collector 7B. Is bent or curved. Thereby, the relative position shift between the uncoated parts 14B of the plurality of layers constituting the lead part 16B can be prevented. In order to effectively prevent the relative displacement between the uncoated portions 14B, it is preferable that the bulging amounts of the bulging portions 43 and 44 are sufficiently large. For example, as shown in FIG. 30, the difference δ3 obtained by subtracting the thickness δ2 of the plate member 41 from the bulging amount δ1 of the bulging portions 43 and 44 is preferably larger than the thickness δ4 of the lead portion 16B.

  Other configurations and operations of the seventh embodiment are the same as those of the first embodiment.

  31 and 32 show an alternative of the seventh embodiment. The bulging portions 43 and 44 in the alternative shown in FIG. 31 are not provided with openings 43a and 44a (see, for example, FIG. 28), and a substantially flat rectangular parallelepiped closed space inside the bulging portions 43 and 44. Is formed. A crimping portion 42d is also provided at a position near the end of the electrode body 3 with respect to the bulging portions 43 and 44 provided with the welded portion 17 (a position on the side opposite to the active material layer 13B). In the alternative shown in FIG. 32, the direction in which the bulging portions 43 and 44 bulge is opposite to that of the seventh embodiment. That is, in the alternative shown in FIG. 32, the bulging portions 43 and 44 bulge in the direction from the innermost layer to the outermost layer of the lead portion 16B. In the case of the alternative bulging portions 43 and 44 in FIG. 31, the bulging portions may be bulged in the direction from the innermost layer to the outermost layer of the lead portion 16B.

  Although the present invention has been described by taking a lithium ion secondary battery as an example, the present invention can be applied to various power storage elements including non-aqueous electrolyte secondary batteries other than lithium ion secondary batteries.

  The present invention can also be applied to an electricity storage device including an electrode body having a structure in which a plate-like positive electrode body and a negative electrode body are laminated in a plurality of layers with a separator interposed therebetween.

  Moreover, you may provide a close part (pressing part, pressing part, or crimping part) only in any one of the positive electrode side and the negative electrode side.

DESCRIPTION OF SYMBOLS 1 Battery 2 Exterior body 2a Case main body 2b Cover 3 Electrode body 4A, 4B External terminal 5 Connection member 6 Rivet 7A, 7B Current collector 7a Base part 7b Leg part 7c Bending part 8 Upper packing 9 Lower packing 10 Separator 11A Positive electrode body 11B Negative electrode body 12A, 12B Conductive sheet 13A, 13B Active material layer 14A, 14B Uncoated portion 16A, 16B Lead portion 17 Welded portion 18 Press contact portion (close contact portion)
18a Center part 18b Side part 21 Clip 22 Partition plate (compression element)
22a insertion hole 22b hole edge 23 compression part (close part)
24 Elastic member (caulking element)
24a Pressure part 24b Connection part 24c 1st part 24d 2nd part 25 Clamping part (close part)
25a Central part 25b Side part 28 Elastic member (caulking element)
28a Pressure part 28b Connection part 28c 1st part 28d 2nd part 28e 3rd part 28f Wire rod 28g Ridge part 31 Caulking tool (caulking element)
31a Bottom part 31b Frame wall part 31c, 31d, 31e Slit 31f First part 31g Second part 31h Third part 31i First part 31j Second part 31k Third part 32A, 32B Half part 32a Bottom wall part 32b, 32c, 32d Side wall portion 32e, 32f, 32g Notch 33 Caulking tool (caulking element)
34A, 34B Fitting member 34a Flat portion 34b Edge portion 34c Convex portion 34d Concavity 41 Plate member 42a, 42b, 42c, 42d Clamping portion 43, 44 Expansion portion 43a, 44a Opening 43b, 44b Top wall portion 124, 125 Addition Pressure part 124a, 125a First part 124b, 125b Second part 126, 127 Connecting part 126a, 127a First part 126b, 127b Second part

Claims (13)

An external terminal,
The conductive sheet is formed by laminating a separator with a separator interposed therebetween, and the conductive sheet includes a portion where an active material layer is formed and an uncoated portion which is a region where the active material layer is not provided. An electrode body having a lead portion formed by stacking a plurality of uncoated portions of the sheet;
A current collector that electrically connects the lead portion of the electrode body and the external terminal;
A welded portion in which the lead portion and the current collector are welded and connected;
The uncoated portion of the plurality of layers constituting the lead portion, and a close portion that is close to each other at the location of the active material layer side than at least the welded portion,
The close contact portion is a storage element , which is a press contact portion formed by pressing the uncoated portions of the plurality of layers constituting the lead portion in the stacking direction . The dimensions of the pressure-contact portion between said contact portion in a direction perpendicular to the active material layer and the direction are arranged is larger than the dimension of the welded portion, the electric storage device according to claim 1. An external terminal,
The conductive sheet is formed by laminating a separator with a separator interposed therebetween, and the conductive sheet includes a portion where an active material layer is formed and an uncoated portion which is a region where the active material layer is not provided. An electrode body having a lead portion formed by stacking a plurality of uncoated portions of the sheet;
A current collector that electrically connects the lead portion of the electrode body and the external terminal;
A welded portion in which the lead portion and the current collector are welded and connected;
A close contact portion in which the uncoated portions of the plurality of layers constituting the lead portion are brought into close contact with each other at least at a position closer to the active material layer than the weld portion;
With
A compression element that compresses the uncoated portion of the plurality of layers constituting the lead portion in the stacking direction,
The close contact portion is a compression portion in which a plurality of uncoated portions are compressed in the stacking direction by the compression element,
The compression element includes an insertion hole for inserting the lead portion,
The compression part is formed by pressing the uncoated part of a plurality of layers in the stacking direction by a hole edge of the insertion hole,
The compression element includes a first region in which the insertion hole is formed and including the lead portion of the electrode body, and a second region including a portion excluding the lead portion of the electrode body. An electricity storage element , which is a partition member that partitions the electrolyte solution from the region so as not to allow the electrolyte solution to flow out to the first region . An external terminal,
The conductive sheet is formed by laminating a separator with a separator interposed therebetween, and the conductive sheet includes a portion where an active material layer is formed and an uncoated portion which is a region where the active material layer is not provided. An electrode body having a lead portion formed by stacking a plurality of uncoated portions of the sheet;
A current collector that electrically connects the lead portion of the electrode body and the external terminal;
A welded portion in which the lead portion and the current collector are welded and connected;
A close contact portion in which the uncoated portions of the plurality of layers constituting the lead portion are brought into close contact with each other at least at a position closer to the active material layer than the weld portion;
With
A caulking element for caulking the uncoated portion of the plurality of layers constituting the lead portion in the stacking direction;
The close contact portion is a caulking portion obtained by caulking the uncoated portions of a plurality of layers in the stacking direction by the caulking element,
The said crimping element is an electrical storage element which is an elastic member which elastically pinches | interposes the said uncoated part of multiple layers . The power storage element according to claim 4 , wherein the elastic member includes a pair of pressure units that elastically sandwich the uncoated portions of the plurality of layers. The electric storage element according to claim 5 , wherein one of the pair of pressurizing parts is located on the inner side with respect to the other when viewed from a direction in which the uncoated part is elastically sandwiched. An external terminal,
The conductive sheet is formed by laminating a separator with a separator interposed therebetween, and the conductive sheet includes a portion where an active material layer is formed and an uncoated portion which is a region where the active material layer is not provided. An electrode body having a lead portion formed by stacking a plurality of uncoated portions of the sheet;
A current collector that electrically connects the lead portion of the electrode body and the external terminal;
A welded portion in which the lead portion and the current collector are welded and connected;
A close contact portion in which the uncoated portions of the plurality of layers constituting the lead portion are brought into close contact with each other at least at a position closer to the active material layer than the weld portion;
With
A caulking element for caulking the uncoated portion of the plurality of layers constituting the lead portion in the stacking direction;
The close contact portion is a caulking portion obtained by caulking the uncoated portions of a plurality of layers in the stacking direction by the caulking element,
The caulking element includes a first member and a second member coupled in a fixed state to each other,
The power storage element , wherein the crimping portion is formed by being sandwiched between the first member and the second member . The storage element according to claim 7 , wherein a slit for sandwiching the uncoated portions of the plurality of layers is formed in a state where the first member and the second member are coupled. The electricity storage device according to claim 8 , wherein the slit has a polygonal line shape. An external terminal,
The conductive sheet is formed by laminating a separator with a separator interposed therebetween, and the conductive sheet includes a portion where an active material layer is formed and an uncoated portion which is a region where the active material layer is not provided. An electrode body having a lead portion formed by stacking a plurality of uncoated portions of the sheet;
A current collector that electrically connects the lead portion of the electrode body and the external terminal;
A welded portion in which the lead portion and the current collector are welded and connected;
A close contact portion in which the uncoated portions of the plurality of layers constituting the lead portion are brought into close contact with each other at least at a position closer to the active material layer than the weld portion;
With
A caulking element for caulking the uncoated portion of the plurality of layers constituting the lead portion in the stacking direction;
The close contact portion is a caulking portion obtained by caulking the uncoated portions of a plurality of layers in the stacking direction by the caulking element,
A plate member for sandwiching the uncoated portions of the plurality of layers between the current collectors;
The power storage element , wherein the crimping element includes the current collector and the plate member . The current collector and the plate member are each provided with a bulging portion, and the bulging portion provided on the other side is disposed in the bulging portion provided on one side of the current collector and the plate member,
The electrical storage element according to claim 10 , wherein the welded portion is formed in a portion sandwiched between the concave portion and the convex portion in the uncoated portion of the plurality of layers. The power storage element according to claim 11 , wherein the crimping portion is provided in a portion other than the portion other than the bulging portion. Preparing a conductive sheet comprising a portion where an active material layer is formed and an uncoated portion which is a region where the active material layer is not provided;
Laminating the conductive sheet with a separator interposed therebetween, and forming an electrode body including a lead portion in which a plurality of uncoated portions of the conductive sheet overlap,
As the intimate part in which the uncoated parts of the plurality of layers constituting the lead part are partially in close contact with each other , a pressure contact part in which the uncoated part is pressed in the stacking direction is formed,
A method for manufacturing a storage element, comprising forming a welded portion by welding the lead portion and a current collector at a position opposite to the active material layer with respect to the close contact portion.

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