JP2019046803A - Power storage element and power storage device - Google Patents

Abstract

To provide a power storage element capable of increasing a junction area of two conductive members arranged in a main current path.SOLUTION: A power storage element 10 provided with an electrode body 400 includes a first conductive member and a second conductive member disposed in a path of current flowing through the electrode body 400 and joined to each other, and the first conductive member and the second conductive member includes a first caulking joint portion 21 formed of a uneven structure in which a first portion 521 of one of the members protrudes toward a second portion 411 included in the other member. The first caulking joint portion 21 includes a second caulking joint portion 22 formed of a uneven structure in which a third part 524 of one of the first portion 521 and the second portion 411 protrudes toward a fourth part 414 included in the other portion.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a storage element and a storage device including two conductive members disposed in a path of current flowing in an electrode body and joined to each other.

  2. Description of the Related Art Conventionally, a storage element is known which includes two conductive members disposed in a path of current flowing through an electrode body and joined to each other. For example, Patent Document 1 discloses a storage element having a configuration in which an electrode body and a current collector are joined.

JP, 2016-189323, A

  Here, in the above-mentioned conventional storage element, two conductive members (electrode body and current collector) are crimped and joined, but generally, when two conductive members are crimped and joined, ultrasonic waves are generated. The contact area (joining area) is reduced compared to joining such as welding. However, since these two conductive members are members disposed in the path of the current (main current) flowing through the electrode body, when the bonding area is reduced, the conduction resistance is increased. For this reason, it is desirable to increase the junction area in the two conductive members disposed in the main current path.

  The present invention has been made in view of the above problems, and it is an object of the present invention to provide an electric storage device and an electric storage device capable of increasing the bonding area of two conductive members arranged in a main current path.

  In order to achieve the above object, an electricity storage device according to one aspect of the present invention is an electricity storage device including an electrode body, which is disposed in a path of current flowing through the electrode body, and is joined to each other A first caulking provided with a second conductive member, wherein the first conductive member and the second conductive member are each formed by a concavo-convex structure in which the first portion of either one protrudes toward the second portion of the other. An uneven structure in which the first caulking joint has a joint and the third part of one of the first part and the second part protrudes toward the fourth part of the other. And a second crimped joint formed in

  According to this, in the storage element, the first conductive member and the second conductive member disposed in the path of the current flowing through the electrode body and joined to each other have the first caulking joint, and the first caulking joint is , A second crimped joint. That is, in the bonding of the first conductive member and the second conductive member disposed in the main current path, double caulking bonding is performed in which a second caulking bonding portion is formed in the first caulking bonding portion. Thus, the junction area at the first crimped junction can be increased by forming the second crimped junction, thereby increasing the junction area of the two conductive members disposed in the main current path. it can.

  In addition, the first part may have a first protrusion projecting in a first direction toward the second part, and the first protrusion may protrude in a second direction intersecting the first direction. The third portion has a second protrusion, and the third portion has a third protrusion protruding in a third direction toward the fourth portion, and the third protrusion crosses the third direction. It is also possible to have a fourth protrusion projecting in the direction.

  According to this, in the first crimp joint, the first projection projecting in the first direction has the second projection projecting in the second direction intersecting the first direction, and the second crimp joint In the portion, the third projecting portion projecting in the third direction has a fourth projecting portion projecting in a fourth direction intersecting the third direction. That is, in the first caulking joint, a second projection is formed on the first projection to perform an interlock shape, and clinching and caulking is performed, and in the second caulking joint, the fourth projection is formed in the third projection. Is formed to form an interlock shape. As described above, in caulking and bonding the first conductive member and the second conductive member, the second protrusion is formed in the first protrusion and the fourth protrusion is formed in the third protrusion. The bonding area of the conductive member and the second conductive member can be further increased.

  Further, the direction in which the third portion protrudes toward the fourth portion may be the same as the direction in which the first portion protrudes toward the second portion.

  According to this, in the direction in which the third part protrudes toward the fourth part in the second crimped joint (the projecting direction of the second crimped joint), the first part is the second part in the first crimped joint. It is the same direction as the direction in which it protrudes (the protruding direction of the first crimped joint). Here, there are many cases where no space is provided between parts for increasing the capacity of the storage element, and when caulking and joining two members of the storage element, the installation space of the die and punch at the time of caulking and joining In many cases it is difficult to secure Therefore, by making the projecting direction of the second crimp joint the same as the projecting direction of the first crimp joint, the first crimp joint and the second crimp joint can be formed to project in the same direction. Therefore, the first caulking joint and the second caulking joint can be formed by one caulking operation. This makes it possible to easily form a crimped joint without having to reposition the die and punch to different positions or repositioning a different die and punch.

  The direction in which the third part protrudes toward the fourth part may be opposite to the direction in which the first part protrudes toward the second part.

  According to this, in the direction in which the third part protrudes toward the fourth part in the second crimped joint (the projecting direction of the second crimped joint), the first part is the second part in the first crimped joint. The direction opposite to the direction of protrusion (the direction of protrusion of the first crimped joint). Here, it is preferable to save space in the storage element in order to increase the capacity. For this reason, by setting the projecting direction of the second caulking joint opposite to the projecting direction of the first caulking joint, the second caulking joint can be prevented from further protruding from the first caulking joint. Space saving can be achieved.

  Further, the first conductive member and the second conductive member have a pair of the first caulking joints at opposing positions, and the pair of first caulking joints are at a pair opposing to each other. It may have a caulking joint.

  According to this, the first conductive member and the second conductive member have a pair of first caulking joints at opposing positions, and the pair of first caulking joints are at a pair of opposing second caulking positions. It has a joint. Here, in the storage element, a spacer or the like for restricting the movement of the first conductive member and the second conductive member is arranged so that the first conductive member and the second conductive member do not move and damage the internal members. There is a case. Therefore, the pair of first caulking joints are disposed at opposing positions so as to sandwich the spacer. Then, in order to position the spacer relative to the first conductive member and the second conductive member, a pair of second crimped joints facing each other are disposed at the pair of first crimped joints. As described above, by positioning the spacer at an accurate position by the pair of second caulking joints, movement of the first conductive member and the second conductive member can be effectively suppressed.

  Further, the electrode body has stacked electrode plates, the first conductive member is a stacked electrode plate of the electrode body, and the second conductive member is a current collector. It is also good.

  According to this, the first conductive member is an electrode plate on which the electrode body is stacked, and the second conductive member is a current collector. Here, when the electrode body and the current collector are crimped and joined, a high effect can be obtained by using the configuration of the present application. That is, since the electrode plate of the electrode body is thin, if the contact area with the current collector is reduced and the current resistance is increased, the electrode may be melted and damaged. For this reason, by performing double caulking and bonding, the bonding area between the stacked electrode plate and the current collector can be increased, so that damage to the electrode plate of the electrode body can be suppressed. In addition, since bonding between the laminated electrode plate and the current collector is easily released, bonding strength between the laminated electrode plate and the current collector can be strengthened by performing double caulking.

  Further, a power storage device according to one aspect of the present invention is a power storage device including a power storage element having an electrode body, wherein the first conductive member and the second power conductor disposed in a path of current flowing through the electrode body and joined to each other A first caulking joint portion including a conductive member, wherein the first conductive member and the second conductive member are formed with a concavo-convex structure in which a first portion of one of the first and second conductive members protrudes toward a second portion of the other. And the first caulking joint is formed with a concavo-convex structure in which the third part of one of the first part and the second part protrudes toward the fourth part of the other. Having a second crimped joint.

  According to this, in the power storage device, the first conductive member and the second conductive member disposed in the path of the current flowing through the electrode body and joined to each other have the first crimped joint and the first crimped joint is the first crimped joint , A second crimped joint. That is, in the connection of the first conductive member and the second conductive member arranged in the main current path in the storage device, double caulking bonding is performed in which a second caulking bonding portion is formed in the first caulking bonding portion. ing. As the first conductive member and the second conductive member, not only the members in the storage element but, for example, the electrode terminal and the bus bar of the storage element, the two members in the case where the bus bar is composed of two members, etc. It can apply. Thus, the junction area at the first crimped junction can be increased by forming the second crimped junction, thereby increasing the junction area of the two conductive members disposed in the main current path. it can.

  The present invention can be realized not only as such a storage element or storage device, but also as two conductive members (a first conductive member and a second conductive member) included in the storage device or the storage device. be able to.

  According to the storage element or the like in the present invention, it is possible to increase the bonding area of the two conductive members arranged in the path of the main current.

It is a perspective view which shows the external appearance of the electrical storage element which concerns on embodiment. It is a perspective view which shows the component arrange | positioned inside the container of the electrical storage element which concerns on embodiment. It is a disassembled perspective view which disassembles the electrical storage element which concerns on embodiment, and shows each component. It is sectional drawing which shows the structure in the state by which the positive electrode collector which concerns on embodiment was joined to the positive electrode focusing | converging part of an electrode body. It is a perspective view which shows the structure of the junction part of the positive electrode collector and electrode body which concern on embodiment. It is sectional drawing which shows the internal structure of the junction part of the positive electrode collector and electrode body which concern on embodiment. It is a perspective view which shows the structure of the junction part of the positive electrode collector and electrode body which concern on the modification of embodiment. It is sectional drawing which shows the internal structure of the junction part of the positive electrode collector and electrode body which concerns on the modification of embodiment.

  Hereinafter, an electric storage device and an electric storage device according to an embodiment (and its modification) of the present invention will be described with reference to the drawings. The embodiments described below are all inclusive or specific examples. The numerical values, shapes, materials, components, arrangement positions and connection forms of the components, and the like described in the following embodiments are merely examples, and are not intended to limit the present invention. Further, among the components in the following embodiments, components not described in the independent claim indicating the highest concept are described as arbitrary components. Further, in the drawings, the dimensions and the like are not strictly illustrated.

  Further, in the following description and drawings, the arrangement direction of the pair of electrode terminals included in the storage element, the arrangement direction of the pair of current collectors, the arrangement direction of both end portions of the electrode body (a pair of active material layers not formed) The winding axial direction of the electrode body, the width direction of the legs of the current collector, or the opposing direction of the short side of the container is defined as the X-axis direction. In addition, the opposite direction of the long side of the container, the short direction of the short side of the container, the thickness direction of the container, the lamination direction of the electrode plates of the electrode assembly at the caulking joint, or the current collector and the electrode body at the caulking joint The alignment direction of the and the cover members is defined as the Y axis direction. Further, the direction in which the container body and the lid of the storage element are aligned, the longitudinal direction of the short side of the container, or the extending direction of the leg portion of the current collector is defined as the Z-axis direction. The X-axis direction, the Y-axis direction, and the Z-axis direction are directions intersecting with each other (orthogonal in the present embodiment). Further, in the following description, for example, the X axis direction plus side indicates the arrow direction side of the X axis, and the X axis direction minus side indicates the opposite side to the X axis direction plus side. The same applies to the Y-axis direction and the Z-axis direction.

Embodiment
[1. General Description of Storage Element 10]
First, general description of the storage element 10 according to the present embodiment will be given using FIGS. 1 to 3. FIG. 1 is a perspective view showing the appearance of a storage element 10 according to the present embodiment. Moreover, FIG. 2 is a perspective view which shows the component arrange | positioned inside the container 100 of the electrical storage element 10 which concerns on this Embodiment. Specifically, FIG. 2 is a perspective view showing a configuration in which the container body 111 is separated from the storage element 10. That is, the figure shows a state after the positive electrode current collector 500 and the negative electrode current collector 600 are joined to the electrode body 400. FIG. 3 is an exploded perspective view showing each component by decomposing the storage element 10 according to the present embodiment. That is, the figure shows a state before the positive electrode current collector 500 and the negative electrode current collector 600 are bonded to the electrode body 400. Moreover, in the same figure, the container main body 111 is abbreviate | omitted and shown in figure.

  The storage element 10 is a secondary battery capable of charging and discharging electricity, and specifically, a non-aqueous electrolyte secondary battery such as a lithium ion secondary battery. The storage element 10 is used, for example, as a power supply for vehicles such as an electric vehicle (EV), a hybrid electric vehicle (HEV) or a plug-in hybrid electric vehicle (PHEV), a power supply for electronic devices, a power supply for power storage, and the like. The storage element 10 is not limited to the non-aqueous electrolyte secondary battery, and may be a secondary battery other than the non-aqueous electrolyte secondary battery, or may be a capacitor. In addition, the storage element 10 may not be a secondary battery, but may be a primary battery that can use the stored electricity without charging by the user. Further, although the rectangular parallelepiped (square) storage element 10 is illustrated in the present embodiment, the shape of the storage element 10 is not limited to the rectangular shape, and may be other than a cylindrical shape, a long cylindrical shape, or a rectangular solid. It may be in the shape of a polygonal column or the like, or may be a laminate type storage element.

  As shown in FIG. 1, the storage element 10 includes a container 100, a positive electrode terminal 200, and a negative electrode terminal 300. Further, as shown in FIG. 2, an electrode body 400, a positive electrode current collector 500, and a negative electrode current collector 600 are accommodated inside the container 100.

  Although a gasket or the like is disposed between the lid 110 and the positive electrode terminal 200 and between the lid 110 and the positive electrode current collector 500 in order to enhance the insulation and air tightness, in FIG. The illustration is omitted. The same applies to the negative electrode side. Moreover, although the electrolyte solution (non-aqueous electrolyte) is enclosed in the inside of the container 100, illustration is abbreviate | omitted. In addition, as the said electrolyte solution, if it does not impair the performance of the electrical storage element 10, there will be no restriction | limiting in particular in the type, A various thing can be selected. In addition to the above components, a spacer disposed on the side of the positive electrode current collector 500 and the negative electrode current collector 600, a gas discharge valve for releasing the pressure when the pressure in the container 100 is increased, Alternatively, an insulating film or the like that wraps the electrode body 400 or the like may be disposed.

  The container 100 is configured of a container body 111 having a rectangular cylindrical bottom and a bottom, and a lid 110 which is a plate-like member for closing the opening of the container body 111. In addition, the container 100 can seal the inside by welding the lid 110 and the container main body 111 after the electrode body 400 and the like are accommodated therein. The material of the lid 110 and the container main body 111 is not particularly limited, and may be, for example, a weldable metal such as stainless steel, aluminum, or an aluminum alloy, but a resin may also be used.

  The electrode assembly 400 includes a positive electrode plate, a negative electrode plate, and a separator, and is a storage element (power generation element) capable of storing electricity. The positive electrode plate is an electrode plate in which a positive electrode active material layer is formed on a positive electrode base material layer which is a long strip-like current collector foil made of aluminum, aluminum alloy or the like. The negative electrode plate is an electrode plate in which a negative electrode active material layer is formed on a negative electrode base material layer which is a long strip-like current collector foil made of copper, copper alloy or the like. In addition, well-known materials, such as nickel, iron, stainless steel, titanium, baked carbon, a conductive polymer, conductive glass, an Al-Cd alloy, can also be used suitably as said current collector foil. In addition, as the positive electrode active material and the negative electrode active material used for the positive electrode active material layer and the negative electrode active material layer, known materials can be appropriately used as long as they are active materials capable of inserting and extracting lithium ions. Moreover, the separator can use the microporous sheet and non-woven fabric which consist of resin, for example.

  The electrode body 400 is formed by arranging and winding a separator between the positive electrode plate and the negative electrode plate. Specifically, in the electrode body 400, the positive electrode plate and the negative electrode plate are wound so as to be mutually shifted in the direction of the winding axis (virtual axis parallel to the X-axis direction in this embodiment) via the separator. ing. And a portion (active material layer non-forming portion) where the active material is not coated (the active material layer is not formed) on the end of each of the positive electrode plate and the negative electrode plate in the shifted direction (the active material layer is not formed) )have.

  That is, the electrode assembly 400 has stacked electrode plates (a positive electrode plate and a negative electrode plate). The electrode body 400 has the positive electrode focusing portion 410 in which the active material layer non-formed portion of the positive electrode plate is stacked and bundled at one end in the winding axial direction (the end on the positive side in the X axis direction). There is. In addition, the electrode body 400 has the negative electrode focusing portion 420 in which the active material layer non-formed portion of the negative electrode plate is stacked and bundled at the other end portion in the winding axial direction (the end portion on the negative side in the X axis direction). ing. For example, the thickness of the active material layer non-forming portion (current collecting foil) of the positive electrode plate and the negative electrode plate is about 5 μm to 20 μm, and by bundling about 30 to 40 sheets, for example, positive electrode focusing portion 410 and negative electrode focusing The part 420 is formed. In the present embodiment, an oval shape is illustrated as the cross-sectional shape of the electrode body 400, but it may be circular or elliptical.

  The positive electrode terminal 200 is an electrode terminal electrically connected to the positive electrode plate of the electrode body 400, and the negative electrode terminal 300 is an electrode terminal electrically connected to the negative electrode plate of the electrode body 400. That is, positive electrode terminal 200 and negative electrode terminal 300 lead the electricity stored in electrode assembly 400 to the external space of storage element 10, and the electricity in the internal space of storage device 10 for storing electricity in electrode assembly 400. It is a metal electrode terminal for introducing The positive electrode terminal 200 and the negative electrode terminal 300 are attached to a lid 110 disposed above the electrode assembly 400. Specifically, as shown in FIG. 3, in the positive electrode terminal 200, the protrusion 210 is inserted into the through hole 110a of the lid 110 and the opening 511 of the positive electrode current collector 500 and caulking is performed. It is fixed to the lid 110 together with the current collector 500. The same applies to the negative electrode terminal 300.

  The positive electrode current collector 500 is disposed between the positive electrode focusing portion 410 of the electrode body 400 and the side wall of the container body 111, and has conductivity and rigidity electrically connected to the positive electrode terminal 200 and the positive electrode plate of the electrode body 400. And a member provided with In addition, the negative electrode current collector 600 is disposed between the negative electrode focusing portion 420 of the electrode body 400 and the sidewall of the container body 111, and is electrically connected to the negative electrode terminal 300 and the negative electrode plate of the electrode body 400. And the rigidity.

  Specifically, the positive electrode current collector 500 and the negative electrode current collector 600 are arranged in a bent state along the side wall and the lid 110 from the side wall of the container body 111 to the lid 110. It is a member. The positive electrode current collector 500 and the negative electrode current collector 600 are fixedly connected (joined) to the lid 110. In addition, the positive electrode current collector 500 and the negative electrode current collector 600 are fixedly connected (joined) to the stacked electrode plates of the electrode assembly 400, that is, the positive electrode focusing portion 410 and the negative electrode focusing portion 420. With this configuration, the electrode assembly 400 is held (supported) in a state of being suspended from the lid 110 by the positive electrode current collector 500 and the negative electrode current collector 600, and shaking due to vibration or impact is suppressed.

  Although the material of the positive electrode current collector 500 is not limited, for example, like the positive electrode base layer of the electrode assembly 400, it is formed of aluminum or an aluminum alloy. Also, the material of the negative electrode current collector 600 is not limited, but, for example, like the negative electrode base layer of the electrode assembly 400, it is formed of copper or a copper alloy.

[Description of Configuration Around Junction 20]
Here, as shown in FIG. 2, the positive electrode current collector 500 is bonded to the positive electrode focusing portion 410 of the electrode assembly 400 at a plurality of bonding portions 20. Further, the negative electrode current collector 600 is bonded to the negative electrode focusing portion 420 of the electrode body 400 at a plurality of bonding portions 30. The schematic configuration around the bonding portions 20 and 30 will be described below also using FIG. The periphery of the positive electrode side joint 20 and the periphery of the negative electrode side joint 30 have the same configuration, and therefore, the configuration around the positive electrode side junction 20 will be described below. The description of the configuration around the unit 30 is omitted.

  FIG. 4 is a cross-sectional view showing a configuration in which positive electrode current collector 500 according to the present embodiment is joined to positive electrode focusing portion 410 of electrode assembly 400. Specifically, the figure shows a configuration in the case where the positive electrode current collector 500 and the positive electrode focusing portion 410 shown in FIG. 2 are cut along the YZ plane passing through the bonding portion 20.

  As shown in FIGS. 3 and 4, the positive electrode current collector 500 includes a terminal connection portion 510 and two electrode connections extending from both end portions of the terminal connection portion 510 in the Y-axis direction toward the negative side in the Z-axis direction. And a part 520.

  The terminal connection portion 510 is a base of the positive electrode current collector 500 connected (joined) to the positive electrode terminal 200. That is, the terminal connection portion 510 is a flat plate-like portion disposed on the positive electrode terminal 200 side (upper side, positive side in the Z-axis direction) of the positive electrode current collector 500, and is electrically and mechanically connected to the positive electrode terminal 200. Ru.

  The electrode connection portion 520 is a leg portion of the positive electrode current collector 500 connected (joined) to the electrode body 400. That is, the electrode connection portion 520 is a portion disposed on the electrode body 400 side (lower side, the negative side in the Z-axis direction) of the positive electrode current collector 500, and is electrically and mechanically connected to the electrode body 400. Specifically, the electrode connection portion 520 is a long and flat portion extending in the Z-axis direction, and in two positive flat focusing portions of the positive electrode focusing portion 410 of the electrode assembly 400, two electrode flat portions are provided. The electrode connection parts 520 are respectively joined.

  Further, as shown in FIG. 4, the cover member 700 is disposed inside the positive electrode focusing portion 410, and the electrode connection portion 520, the positive electrode focusing portion 410 and the cover member 700 are mechanically joined together to form four. Junctions 20 (two for each of the two electrode connection portions 520) are formed. That is, the laminated electrode plate of the electrode body 400 and the positive electrode current collector 500 are provided with the joint portion 20 fitted with each other in a concavo-convex structure in which one of the electrode plate 400 protrudes toward the other. Specifically, the bonding portion 20 is a bonding portion of a concavo-convex structure in which the electrode connection portion 520 protrudes toward the positive electrode focusing portion 410, and the electrode connection portion 520 and the positive electrode focusing portion 410 are fitted and bonded to each other. ing. The bonding portion 20 can be formed, for example, by caulking the electrode connection portion 520, the positive electrode focusing portion 410, and the cover member 700 (specifically, by performing a clinching caulking bonding).

  Here, the stacked electrode plate of the electrode body 400 is an example of a first conductive member, and the positive electrode current collector 500 is an example of a second conductive member. That is, the laminated electrode plate of the electrode assembly 400 and the positive electrode current collector 500 are an example of the first conductive member and the second conductive member which are disposed in the path of the current flowing through the electrode assembly 400 and joined to each other. The current flowing through the electrode body 400 is a charging current or a discharging current (main current), and is a current flowing between the electrode body 400 and the positive electrode terminal 200 and the negative electrode terminal 300. Further, the path of the current is a current path between the electrode body 400 and the positive electrode terminal 200 and the negative electrode terminal 300.

  The joint portion 20 is a cylindrical projecting portion, and the two joint portions 20 are disposed so as to protrude toward each other at positions facing each other. That is, the first conductive member and the second conductive member have two (two pairs) of the pair of bonding portions 20 at the positions facing each other in the Y-axis direction. Specifically, the first conductive member and the second conductive member have a pair of first caulking joints 21 at opposing positions, and the pair of first caulking joints 21 at a pair of opposing positions. A caulking joint 22 is provided. The detailed description of the configuration of the bonding portion 20 will be described later.

  In addition, the cover member 700 is a cover that is disposed at a position sandwiching the positive electrode focusing portion 410 with the electrode connection portion 520 and that protects the positive electrode focusing portion 410. Specifically, the cover member 700 is a rectangular and flat plate-shaped member extending in the Z-axis direction along the positive electrode focusing portion 410, and is formed to have a uniform thickness before bonding. There is. The material of the cover member 700 is not particularly limited. For example, the cover member 700 is a metal member formed of aluminum or an aluminum alloy as in the case of the positive electrode base layer of the electrode assembly 400. A cover member is similarly disposed on the negative electrode side, and the material of the cover member on the negative electrode side is not particularly limited. For example, like the negative electrode base layer of the electrode assembly 400, copper or copper alloy It is a metal member formed by

[Detailed Description of Configuration of Junction 20]
Next, the configuration of the bonding portion 20 will be described in more detail. FIG. 5 is a perspective view showing the configuration of the bonding portion 20 between the positive electrode current collector 500 and the electrode assembly 400 according to the present embodiment. Specifically, this figure is a perspective view of the joint portion 20 on the negative side in the Y-axis direction shown in FIG. 4 as viewed from the cover member 700 side (projecting side). FIG. 6 is a cross-sectional view showing an internal configuration of a bonding portion 20 between the positive electrode current collector 500 and the electrode assembly 400 according to the present embodiment. Specifically, in the figure, the joint 20 shown in FIG. 5 (the joint 20 on the negative side in the Y-axis direction shown in FIG. 4) is cut along the YZ plane including the VI-VI line. It is sectional drawing which shows a structure. In addition, although the direction of the Y-axis direction minus side joint part 20 and the Y-axis direction minus side joint part 20 shown in FIG. 4 is opposite in direction of the Y-axis direction, the configuration is the same, so the description is omitted. Do.

  As shown to these figures, the junction part 20 has the 1st caulking junction part 21 of the upper surface view circular shape protruded to the Y-axis direction plus side, and the 1st crimping junction part 21 is the Y-axis direction plus side. Furthermore, it has the 2nd crimp joint part 22 of the upper surface view circular shape which protruded. In these figures, top view is viewed from the positive side in the Y-axis direction, and for example, circular in top view is circular when viewed from the positive side in the Y-axis direction. It means that.

  The first caulking joint portion 21 has a concavo-convex structure in which the first portion 521 of either one of the stacked electrode plate of the electrode assembly 400 and the positive electrode current collector 500 protrudes toward the second portion 411 of the other. It is a formed site. That is, the first conductive member and the second conductive member have the first caulking joint portion 21 formed of the concavo-convex structure in which the first portion 521 of either one protrudes toward the second portion 411 of the other. doing. In the present embodiment, the first crimped joint portion 21 is a bottomed substantially cylindrical first portion 521 of the electrode connection portion 520 of the positive electrode current collector 500, and a bottomed portion of the positive electrode focusing portion 410 of the electrode assembly 400. It is formed of a concavo-convex structure which protrudes toward the substantially cylindrical second portion 411. The first caulking joint portion 21 is a portion formed by a concavo-convex structure in which the second portion 411 of the positive electrode focusing portion 410 protrudes toward the bottomed substantially cylindrical fifth portion 701 of the cover member 700. It can be said that.

  The second caulking joint portion 22 is formed with a concavo-convex structure in which the third portion 524 of either one of the first portion 521 and the second portion 411 protrudes toward the fourth portion 414 of the other. It is a site. In the present embodiment, the third portion 524 having a substantially cylindrical shape with a bottom having the first portion 521 of the electrode connection portion 520 has a fourth portion 414 having a substantially cylindrical shape with a bottom that the second portion 411 of the positive electrode focusing portion 410 has. It is formed by the concavo-convex structure which protrudes toward. Here, the direction in which the third portion 524 in the second crimp joint 22 protrudes toward the fourth portion 414 is the direction in which the first portion 521 in the first crimp joint 21 protrudes toward the second portion 411. The same direction. In the second crimp joint portion 22, the fourth portion 414 of the second portion 411 of the positive electrode focusing portion 410 is directed to a bottomed, substantially cylindrical sixth portion 704 of the fifth portion 701 of the cover member 700. It can also be said that it is a part formed by the projecting uneven structure.

[3.1 Detailed Description of Configuration of First Caulking Joint 21]
First, the configuration of the first crimp joint 21 will be described in detail. As shown in FIG. 6, the electrode connection portion 520 of the positive electrode current collector 500, the positive electrode focusing portion 410 of the electrode assembly 400, and the cover member 700 have a first projection (protruding in the first direction) The current collector first projection 522, the electrode body first projection 412, and the cover first projection 702) are provided. Here, the first direction is the direction in which the first protrusion protrudes, that is, the direction from the electrode connection portion 520 toward the cover member 700, and in the same figure, it is the Y axis direction plus side. Moreover, the said 1st protrusion part has the 2nd protrusion part (The collector 2nd protrusion part 523 and the electrode body 2nd protrusion part 413) which protrudes in the 2nd direction which cross | intersects a 1st direction. In the present embodiment, the second direction is a direction orthogonal to the first direction, and is all directions in the XZ plane (both sides in the Z-axis direction in the figure).

  The first projection and the second projection are formed, for example, by plastic deformation of the electrode connection portion 520, the positive electrode focusing portion 410, and the cover member 700 in the bonding portion 20. In the present embodiment, in the bonding portion 20, the electrode connection portion 520, the positive electrode focusing portion 410 and the cover member 700 are formed by caulking (specifically, clinching and caulking).

  Specifically, the first portion 521 of the electrode connection portion 520 includes a current-collector first protrusion 522 that protrudes in a first direction toward the second portion 411 of the positive electrode focusing portion 410. The current collector first protrusion 522 is a cylindrical convex portion in which the surface of the electrode connection portion 520 on the positive electrode focusing portion 410 side protrudes to the positive electrode focusing portion 410 side. In other words, the surface of the current-collector first protrusion 522 on the opposite side (outside) of the electrode connection portion 520 to the positive electrode focusing portion 410 has a shape recessed toward the positive electrode focusing portion 410 side. Further, the current-collector first protrusion 522 has a current-collector second protrusion 523 protruding in the second direction. The current collector second projection 523 is annular in top view and protrudes from the end on the first direction side of the current collector first projection 522 toward the electrode body first projection 412 over the entire circumference. It is a site.

  In addition, the second part 411 of the positive electrode focusing part 410 has an electrode body first projecting part 412 protruding in the first direction toward the fifth part 701 of the cover member 700. The electrode body first projecting portion 412 is a cylindrical convex portion in which the surface of the positive electrode focusing portion 410 on the cover member 700 side protrudes toward the cover member 700. In other words, the electrode body first projecting portion 412 has a shape in which the surface of the positive electrode focusing portion 410 on the electrode connection portion 520 side is recessed toward the cover member 700 side. In addition, the electrode body first projecting portion 412 has an electrode body second projecting portion 413 projecting in the first direction and the second direction. The electrode body second projection 413 projects from the end on the first direction side of the electrode body first projection 412 toward the cover first projection 702 and a cover second projection 703 described later over the entire circumference. It is a site | part of a top view annular shape.

  Further, the fifth portion 701 of the cover member 700 has a cover first projecting portion 702 that protrudes in a first direction away from the positive electrode focusing portion 410. The surface of the cover first protrusion 702 on the opposite side (outside) of the cover member 700 to the positive electrode converging portion 410 is a cylindrical convex portion that protrudes outward. In other words, the cover first protrusion 702 has a shape in which the surface on the positive electrode focusing portion 410 side of the cover member 700 is recessed toward the opposite side to the positive electrode focusing portion 410. Further, the cover first protrusion 702 has a cover second protrusion 703 in an annular shape in top view that protrudes in the first direction at an end on the first direction side.

  The current collector first protrusion 522, the electrode body first protrusion 412, the cover first protrusion 702, the current collector second protrusion 523, the electrode second protrusion 413, and the cover second protrusion 703 The projecting direction is not limited to the above direction, and may be a direction inclined from the above direction, and the projecting shape is not limited to the above. The current collector second projection 523 may also project in the first direction, and the electrode body second projection 413 may not project in the first direction, or the cover second projection The portion 703 may not protrude in the first direction. In addition, although the cover second projection 703 may protrude in the second direction from the end on the first direction side of the cover first projection 702, the joining operation is performed by not projecting in the second direction. Later, the joint 20 can be easily removed from the die of the bonding instrument. In this case, the width of the fifth portion 701 (cover first projection 702 and cover second projection 703) of the cover member 700 (in the figure, the width in the Z-axis direction) in order to make the joint 20 easier to remove from the die. ) May be smaller toward the tip.

[3.2 Detailed Description of Configuration of Second Crank Joint 22]
Next, the configuration of the second crimp joint 22 will be described in detail. The third portion 524 of the first portion 521 of the electrode connection portion 520, the fourth portion 414 of the second portion 411 of the positive electrode focusing portion 410, and the sixth portion 704 of the fifth portion 701 of the cover member 700 are The third protrusion (the current collector third protrusion 525, the electrode body third protrusion 415, and the cover third protrusion 705) protruding in the third direction is provided. Here, the third direction is the direction in which the third protrusion protrudes, and in the present embodiment, the direction from the electrode connection portion 520 toward the cover member 700, that is, the same direction as the first direction (in FIG. Y axis direction plus side). In addition, the third projecting portion has a fourth projecting portion (current collector fourth projecting portion 526 and electrode body fourth projecting portion 416) projecting in a fourth direction crossing the third direction. In the present embodiment, the fourth direction is a direction orthogonal to the third direction, that is, the same direction as the second direction (all directions in the XZ plane, both sides in the Z-axis direction in the figure).

  The third and fourth projecting portions are formed, for example, by plastic deformation of the third portion 524, the fourth portion 414, and the sixth portion 704 in the first caulking joint portion 21. In the present embodiment, the third portion 524, the fourth portion 414 and the sixth portion 704 are formed by caulking (in detail, clinching and caulking are performed). That is, by caulking the electrode connection portion 520, the positive electrode focusing portion 410, and the cover member 700 in the bonding portion 20, the first protrusion portion and the second protrusion portion of the first caulking bonding portion 21 and the second caulking bonding portion 22 are A third protrusion and a fourth protrusion are formed.

  Specifically, the third portion 524 of the electrode connection portion 520 includes a current-collector third protrusion 525 that protrudes in the third direction toward the fourth portion 414 of the positive electrode focusing portion 410. The current collector third projecting portion 525 is a cylindrical convex portion in which the surface on the second portion 411 side of the first portion 521 protrudes to the second portion 411 side. In other words, the surface of the current collector third protrusion 525 on the side (outside) opposite to the second portion 411 of the first portion 521 has a shape that is recessed toward the second portion 411. . Also, the current collector third protrusion 525 has a current collector fourth protrusion 526 protruding in the fourth direction. The current collector fourth projecting portion 526 is an annular top view that protrudes from the end in the third direction of the current collector third projecting portion 525 toward the electrode body third projecting portion 415 over the entire circumference. It is.

  In addition, the fourth portion 414 of the positive electrode focusing portion 410 has an electrode body third projecting portion 415 that protrudes in a third direction toward the sixth portion 704 of the cover member 700. The electrode body third projecting portion 415 is a cylindrical convex portion in which the surface on the fifth portion 701 side of the second portion 411 protrudes to the fifth portion 701 side. In other words, the electrode body third projecting portion 415 has a shape in which the surface on the first portion 521 side of the second portion 411 is recessed toward the fifth portion 701 side. Further, the electrode body third projecting portion 415 has an electrode body fourth projecting portion 416 projecting in the third direction and the fourth direction. The fourth electrode body protrusion 416 protrudes from the end of the third electrode body third protrusion 415 in the third direction toward the cover third protrusion 705 and a cover fourth protrusion 706 described later. It is a part of a top view circular shape.

  Further, the sixth portion 704 of the cover member 700 has a cover third projecting portion 705 that protrudes in a third direction in a direction away from the fourth portion 414. The cover third projecting portion 705 is a cylindrical convex portion in which the surface on the opposite side (outside) to the second portion 411 of the fifth portion 701 protrudes outward. In other words, the cover third projecting portion 705 has a shape in which the surface on the second portion 411 side of the fifth portion 701 is recessed toward the opposite side to the second portion 411. Further, the cover third projecting portion 705 has a cover fourth projecting portion 706 having an annular top view and projecting toward the third direction at an end in the third direction.

  The current collector third protrusion 525, the electrode body third protrusion 415, the cover third protrusion 705, the current collector fourth protrusion 526, the electrode body fourth protrusion 416, and the cover fourth protrusion 706 The projecting direction is not limited to the above direction, and may be a direction inclined from the above direction, and the projecting shape is not limited to the above. Also, the current collector fourth projection 526 may project in the first direction, and the electrode body fourth projection 416 may not project in the first direction, or the cover fourth projection The portion 706 may not protrude in the first direction. In addition, although the cover fourth projecting portion 706 may project in the fourth direction from the end in the third direction of the cover third projecting portion 705, by making it not project in the fourth direction, after the joining operation The joint 20 can be easily removed from the die of the joining tool. In this case, the width of the sixth portion 704 (cover third projection 705 and cover fourth projection 706) of the cover member 700 (in the figure, the width in the Z-axis direction) in order to make the joint 20 easier to remove from the die. ) May be smaller toward the tip.

[4 Description of effect]
As described above, according to the storage element 10 according to the embodiment of the present invention, the first conductive members arranged in the path of the current flowing through the electrode assembly 400 and joined to each other (the electrode plate of the electrode assembly 400 laminated And the second conductive member (positive electrode current collector 500) have a first crimped joint 21, and the first crimped joint 21 has a second crimped joint 22. That is, in the bonding of the first conductive member and the second conductive member disposed in the main current path, double caulking bonding is performed in which the second caulking bonding portion 22 is formed in the first caulking bonding portion 21 There is. As a result, the bonding area at the first crimped joint 21 can be increased by forming the second crimped joint 22, and therefore, the bonded area of the two conductive members disposed in the main current path is increased. be able to. In addition, since double caulking bonding is performed in the bonding of the first conductive member and the second conductive member, the bonding strength of the first conductive member and the second conductive member can be strengthened.

  In addition, a caulking joint portion of the first conductive member (the electrode plate on which the electrode body 400 is stacked) and the second conductive member (the positive electrode current collector 500) which are disposed in the path of the main current flowing through the electrode body 400 and joined together. May be located in the electrolyte or in contact with the electrolyte. Even in such a case, by having the double crimped joint, the creeping distance to the penetration of the electrolytic solution can be increased, so that a long-term increase in resistance of the crimped joint can be suppressed. This is an important effect when placed in the main current path.

  Further, in the first crimp joint portion 21, the current-collector first protrusion 522 protruding in the first direction has a current-collector second protrusion 523 protruding in the second direction intersecting the first direction. In the second crimp joint 22, the current-collector third protrusion 525 protruding in the third direction has a current-collector fourth protrusion 526 protruding in the fourth direction intersecting the third direction. There is. That is, in the first crimp joint portion 21, the current collector second projection portion 523 is formed on the current collector first projecting portion 522, and clinching and caulking bonding is performed in an interlock shape, and in the second crimp joint portion 22. Then, the current collector third projecting portion 525 is formed with the current collector fourth projecting portion 526 to perform an interlock shape by clinching and caulking. Thus, in caulking bonding of the first conductive member and the second conductive member, the current collector second protrusion 523 is formed in the current collector first protrusion 522, and the current collector third protrusion 525 is formed. By forming the current collector fourth projecting portion 526, the bonding area of the first conductive member and the second conductive member can be further increased. Further, since the interlock shape is formed in the first caulking joint portion 21 and the second caulking joint portion 22, the joint strength of the first conductive member and the second conductive member can be further strengthened.

  In the direction in which the third portion 524 protrudes toward the fourth portion 414 in the second crimp joint 22 (the direction in which the second crimp joint 22 protrudes), the first portion 521 in the first crimp joint 21 The direction is the same as the direction of protrusion toward the two portions 411 (the direction of protrusion of the first crimp joint 21). Here, the storage element 10 often does not have a space between components for higher capacity, and in the case of caulking and joining two members of the storage element 10, a die and a punch at the time of caulking It is often difficult to secure installation space. For this reason, the first caulking joint portion 21 and the second caulking joint portion 22 are formed to project in the same direction by making the projecting direction of the second caulking joint portion 22 the same as the projecting direction of the first caulking joint portion 21. Therefore, the first caulking joint 21 and the second caulking joint 22 can be formed by one caulking operation. As a result, the joint 20 can be easily formed without the need to reposition the die and the punch in different positions or to reposition the different die and the punch.

  Further, the first conductive member and the second conductive member have a pair of first caulking joints 21 at opposing positions, and the pair of first caulking joints 21 are at a pair of opposing positions. It has a section 22. Here, in the storage element 10, a spacer or the like for restricting the movement of the first conductive member and the second conductive member is arranged so that the first conductive member and the second conductive member do not move and damage the internal members. May. Therefore, the pair of first caulking joints 21 are disposed at opposing positions so as to sandwich the spacer. Then, a pair of second caulking joints 22 facing each other are disposed at the pair of first caulking joints 21 so that the position of the spacer relative to the first conductive member and the second conductive member can be positioned. Thus, by positioning the said spacer in a precise position by a pair of 2nd crimp joint part 22, it can suppress effectively that a 1st electrically-conductive member and a 2nd electrically-conductive member move.

  The first conductive member is a stacked electrode plate of the electrode body 400, and the second conductive member is a positive electrode current collector 500. Here, when the electrode assembly 400 and the positive electrode current collector 500 are crimped and joined, a high effect can be obtained by using the configuration of the present application. That is, since the electrode plate of the electrode assembly 400 is thin, if the contact area with the positive electrode current collector 500 is reduced and the current flow resistance is increased, the electrode may be melted and damaged. For this reason, by performing double caulking, the bonding area between the stacked electrode plate and the positive electrode current collector 500 can be increased, so that the electrode plate of the electrode body 400 is prevented from being damaged. Can. Further, since bonding between the laminated electrode plate and the positive electrode current collector 500 is easily detached, double bonding is performed to strengthen the bonding strength between the laminated electrode plate and the positive electrode collector 500. be able to.

  The negative electrode current collector 600 side also has the same configuration as that of the positive electrode current collector 500 side, so similar effects can be achieved.

[Description of Modification of Fifth Embodiment]
(Modification)
Next, modifications of the above embodiment will be described. FIG. 7 is a perspective view showing a configuration of a bonding portion 20a between a positive electrode current collector 500 and an electrode assembly 400 according to a modification of the present embodiment. The same figure corresponds to FIG. FIG. 8 is a cross-sectional view showing an internal configuration of a bonding portion 20a between a positive electrode current collector 500 and an electrode assembly 400 according to a modification of the present embodiment. Specifically, this figure is a cross-sectional view showing the configuration in the case where the joint portion 20a shown in FIG. 7 is cut along the YZ plane including the line VIII-VIII.

  As shown in these figures, the joint portion 20a in this modification has a second caulking joint portion 22a in place of the second caulking joint portion 22 of the joint portion 20 in the above-described embodiment. The second crimp joint 22 a is disposed so as to project in the direction opposite to the direction in which the first crimp joint 21 protrudes. The other configuration of this modification is the same as that of the above embodiment, and the detailed description will be omitted.

  Specifically, the second caulking joint portion 22a is a concavo-convex portion in which the third portion 414a of one of the first portion 521 and the second portion 411 protrudes toward the fourth portion 524a of the other. It is a site formed of a structure. That is, in this modification, the second portion 411 of the positive electrode focusing portion 410 has the bottomed substantially cylindrical third portion 414a, and the first portion 521 of the electrode connection portion 520 has the bottomed substantially cylindrical fourth portion It has 524a.

  Thus, in the second crimp joint 22a, the third portion 414a of the second portion 411 of the positive electrode focusing portion 410 protrudes toward the fourth portion 524a of the first portion 521 of the electrode connection portion 520. It is formed of a structure. That is, the direction in which the third portion 414a in the second crimp joint 22a protrudes toward the fourth portion 524a is opposite to the direction in which the first portion 521 in the first crimp joint 21 protrudes toward the second portion 411. It is a direction. In addition, the fifth portion 701 of the cover member 700 includes a sixth portion 704 a having a bottom and substantially cylindrical shape, and the sixth portion 704 a corresponds to the third portion 414 a of the second portion 411 of the positive electrode focusing portion 410. It is arranged to project toward the side.

  With the above configuration, the sixth portion 704a, the third portion 414a, and the fourth portion 524a project in the third direction from the third projecting portion (cover third projecting portion 705a, electrode body third projecting portion 415a). And a current collector third projecting portion 525a). Here, the third direction is the direction in which the third protrusion protrudes, and in this modification, the direction from the cover member 700 toward the electrode connection portion 520, that is, the direction opposite to the first direction (in FIG. Y axis direction minus side). Moreover, the said 3rd protrusion part has the 4th protrusion part (the cover 4th protrusion part 706a and the electrode body 4th protrusion part 416a) which protrudes in the 4th direction which cross | intersects a 3rd direction. In the present modification, the fourth direction is a direction orthogonal to the third direction, that is, the same direction as the second direction (all directions in the XZ plane, both sides in the Z-axis direction in the drawing).

  Thus, in the present modification, the relationship between the third portion 524 of the electrode connection portion 520, the fourth portion 414 of the positive electrode focusing portion 410, and the sixth portion 704 of the cover member 700 in the above embodiment is covered. The sixth portion 704 a of the member 700, the third portion 414 a of the positive electrode focusing portion 410, and the fourth portion 524 a of the electrode connection portion 520 are changed. That is, the sixth portion 704a, the third portion 414a, and the fourth portion 524a in this modification are obtained by vertically inverting the third portion 524, the fourth portion 414, and the sixth portion 704 in the above embodiment. For example, the third portion 414 a of the positive electrode focusing portion 410 has an electrode body third projection 415 a that protrudes in the third direction toward the fourth portion 524 a of the electrode connection portion 520. In addition, the electrode body third projecting portion 415 a includes an electrode body fourth projecting portion 416 a that protrudes in the fourth direction.

  As described above, in the storage element 10 according to the present modification, the direction in which the third portion 414a protrudes toward the fourth portion 524a in the second crimped joint 22a (protruding direction of the second crimped joint 22a) Is opposite to the direction in which the first portion 521 protrudes toward the second portion 411 in the first crimp joint 21 (the direction in which the first crimp joint 21 protrudes). Here, it is preferable to save space in the storage element 10 in order to increase the capacity. Therefore, by making the projecting direction of the second crimp joint 22a opposite to the projecting direction of the first crimp joint 21, the second crimp joint 22a is prevented from further projecting from the first crimp joint 21. Space saving can be achieved.

(Other modifications)
As mentioned above, although the electrical storage element 10 which concerns on embodiment and its modification of this invention was demonstrated, this invention is not limited to this embodiment and its modification. That is, it should be understood that the embodiment disclosed this time and the modification thereof are illustrative in all points and not restrictive. The scope of the present invention is indicated not by the above description but by the claims, and is intended to include all the modifications within the meaning and scope equivalent to the claims.

  For example, in the above embodiment and the modification, the first conductive member is a stacked electrode plate of the electrode assembly 400, and the second conductive member is a current collector (a positive electrode current collector 500 or a negative electrode current collector 600). However, the first conductive member and the second conductive member may be members disposed in the path of the current flowing through the electrode body 400 and joined to each other, and are not limited to the electrode body 400 and the current collector. For example, when a conductive member such as a lead is disposed between the electrode body 400 and the current collector, the first conductive member and the second conductive member may be the electrode body 400 and the conductive member. , A current collector and the conductive member.

  Moreover, when the electrode terminal (the positive electrode terminal 200 or the negative electrode terminal 300) is composed of two members, the first conductive member and the second conductive member may be the two members constituting the electrode terminal. When the current collector is composed of two members, the first conductive member and the second conductive member may be the two members constituting the current collector. In addition, the first conductive member and the second conductive member may be an electrode terminal and a current collector. When the container 100 is dropped to the potential of the positive electrode or the negative electrode, the first conductive member and the second conductive member may be the electrode terminal and the container 100, or may be the current collector and the container 100. .

  In addition, the first conductive member and the second conductive member may be included in a storage device (a module including a plurality of storage devices 10 or a pack including a plurality of the modules) including the storage device 10. For example, when the first conductive member and the second conductive member are provided in the module, the first conductive member and the second conductive member may be bus bars between the electrode terminals of the storage element 10 and the storage element 10 Alternatively, the two members in the case where the bus bar between the storage elements 10 is formed by two members may be used. When the first conductive member and the second conductive member are provided in the pack, the first conductive member and the second conductive member may be bus bars between the external terminals of the module and the module, or the module In the case where the bus bar between is constituted by two members, the two members may be employed. Also in these cases, the configurations of the first conductive member and the second conductive member and the effects thereof are the same as those of the above-described embodiment and the modifications thereof.

  Moreover, in the said embodiment and its modification, we decided that the pair of joined parts 20 (or 20a) are arranged in the position which mutually faces. However, the junctions 20 may not be disposed at the opposite positions. Further, the number of bonding portions 20 is not particularly limited, and any number of bonding portions 20 may be formed in the electrode connection portion 520. Further, the number of the electrode connection portions 520 is not limited, and the positive electrode current collector 500 may have only one electrode connection portion 520, and has three or more electrode connection portions 520. You may decide to In addition, when the electrode connection part 520 is made into one, since it is easy to arrange | position a die | dye and punch on both sides of the electrode connection part 520, the junction part 20 can be formed easily.

  Further, in the above-described embodiment and the variation thereof, in the positive electrode current collector 500, the bonding portion 20 (or 20a) is formed on both of the two electrode connection portions 520. The junction 20 may be formed only in one of the two. Further, in the storage element 10, the bonding portion is formed on both of the positive electrode current collector 500 and the negative electrode current collector 600. However, the bonding portion is formed on either the positive electrode current collector 500 or the negative electrode current collector 600. Only the junction may be formed.

  Moreover, in the said embodiment and its modification, it decided that the 1st caulking junction part 21 protrudes in the Y-axis direction positive | plus side or negative | minus side (Y-axis direction positive | plus side in FIG. 5-8). That is, the bonding portion 20 (or 20 a) is a bonding portion of a concavo-convex structure in which the positive electrode current collector 500 protrudes toward the electrode body 400 and the cover member 700. However, the bonding portion 20 may be a bonding portion of a concavo-convex structure in which the cover member 700 and the electrode assembly 400 protrude toward the positive electrode current collector 500. For example, in the case where the cover member 700 is thicker than the positive electrode current collector 500, this configuration is preferable. Further, the projecting direction of the second crimped joint is not limited to the direction in the above-described embodiment and its modification. For example, the second crimp joint may have a configuration in which it protrudes outward from a side surface (a surface on the Z-axis direction side in FIG. 6) of the first crimp joint 21 or a concave configuration or the like. Alternatively, the first crimp joint 21 and the second crimp joint may be squeezed in the height direction (the Y-axis direction in FIG. 6) so as not to protrude outward.

  Moreover, in the said embodiment and its modification, the 1st caulking joint part 21 and the 2nd caulking joint part decided to have a top view circular shape. However, the first crimp joint portion 21 may have an oval shape, an elliptical shape, a polygonal shape, or the like in top view, and the second crimp joint portion may have an oval shape, an oval shape, a polygonal shape, or the like in top view. It may be

  Further, in the above-described embodiment and its modification, in the joint portion 20 (or 20a), one second crimp joint portion is formed in one first crimp joint portion 21, and double caulking junction is performed. I decided that. However, in the joint 20 (or 20 a), two or more second crimp joints may be formed in the first crimp joint 21. Further, in the bonding portion 20 (or 20a), a caulking bonding portion may be further formed in the second caulking bonding portion, and triple or more caulking bonding may be performed.

  In the above-described embodiment and its modification, the first caulking joint 21 and the second caulking joint may be formed by one caulking operation, or the first caulking joint may be divided into a plurality of caulking operations. 21 and a second crimped joint may be formed.

  Further, in the above-described embodiment and the modification, the electrode assembly 400 is a so-called longitudinally wound winding-type electrode assembly in which the winding axis is parallel to the lid 110. However, the electrode assembly 400 may be a so-called laterally wound winding electrode assembly in which the winding axis is perpendicular to the lid 110. Further, the shape of the electrode body 400 is not limited to the winding type, and a stack type in which flat plate-like electrode plates are stacked, or a shape in which electrode plates and / or separators are folded in a bellows shape It may be a form in which it is sandwiched, a form in which the electrode plate and the separator are stacked, and a form in which the sheet is folded.

  Further, in the above-described embodiment and its modification, although the positive electrode current collector 500, the electrode assembly 400, and the cover member 700 are joined, members other than these may be joined together. . Alternatively, the cover member 700 may not be provided, and the positive electrode current collector 500 and the electrode assembly 400 may be bonded to form the bonding portion 20 (or 20a).

  Further, in the above-described embodiment and its modification, although the positive electrode current collector 500 and the electrode assembly 400 are bonded only at the bonding portion 20 (or 20 a), in addition to bonding at the bonding portion 20 Bonding by other bonding methods may be performed. Other joining methods include, for example, ultrasonic welding, resistance welding, arc welding, or welding by irradiating a laser or an electron beam. As described above, by performing bonding by another bonding method in addition to the bonding portion 20 (or 20a), it is possible to improve the bonding strength and reduce the contact resistance.

  Moreover, in the said embodiment and its modification, we decided that one junction part 20 (or 20a) was formed independently. However, a plurality of junctions 20 (or 20a) may be formed in series. For example, adjacent portions of two joints 20 (or 20a) may be integrated to form a shape (twin point) in which two joints 20 (or 20a) are connected, or three or more joints 20 ( Or 20a) may be connected in series to form an integrated shape. Such a configuration can improve the bonding strength and reduce the contact resistance.

  Further, in the above embodiment and the modification thereof, clinching and caulking is illustrated as an example in which the positive electrode current collector 500 and the electrode body 400 are plastically deformed when the positive electrode current collector 500 and the electrode body 400 are bonded. . However, the present invention is not limited to this, and bonding by caulking different in form from clinching caulking may be used.

  Further, a form constructed by arbitrarily combining the components included in the above-described embodiment and the modification thereof is also included in the scope of the present invention.

  Further, the present invention can not only be realized as such a storage element 10 or storage device, but also realized as the storage element 10 or two conductive members (first and second conductive members) included in the storage device. can do.

  The present invention is applicable to storage devices such as lithium ion secondary batteries.

DESCRIPTION OF SYMBOLS 10 electricity storage element 20, 20a, 30 junction part 21 1st caulking junction part 22, 22a 2nd caulking junction part 400 electrode body 410 positive electrode focusing part 411 2nd part 412 electrode body 1st protrusion part 413 electrode body 2nd protrusion part 414 , 524a fourth part 414a, 524 third part 415, 415a electrode body third projecting part 416, 416a electrode body fourth projecting part 420 negative electrode focusing part 500 positive electrode current collector 520 electrode connecting part 521 first part 522 current collector First protrusion 523 Current collector second protrusion 525, 525a Current collector third protrusion 526, 526a Current collector fourth protrusion 600 Negative electrode current collector 700 Cover member

Claims (7)

A storage element comprising an electrode body,
And a first conductive member and a second conductive member disposed in a path of current flowing through the electrode body and joined to each other,
The first conductive member and the second conductive member have a first caulking joint portion formed with a concavo-convex structure in which a first portion of either one protrudes toward a second portion of the other,
The first caulking joint is formed by a concavo-convex structure in which a third part of one of the first part and the second part is projected toward a fourth part of the other. A storage element having a caulking junction. The first part has a first protrusion projecting in a first direction toward the second part,
The first protrusion includes a second protrusion protruding in a second direction intersecting the first direction,
The third portion has a third protrusion projecting in a third direction toward the fourth portion,
The storage element according to claim 1, wherein the third protrusion has a fourth protrusion protruding in a fourth direction intersecting the third direction. The storage element according to claim 1, wherein a direction in which the third part protrudes toward the fourth part is the same as a direction in which the first part protrudes toward the second part. The storage element according to claim 1, wherein a direction in which the third part protrudes toward the fourth part is opposite to a direction in which the first part protrudes toward the second part. The first conductive member and the second conductive member have a pair of the first caulking joints at opposing positions,
The storage element according to any one of claims 1 to 4, wherein the pair of first crimped joints have a pair of second crimped joints at opposing positions. The electrode body has stacked electrode plates,
The first conductive member is a stacked electrode plate of the electrode body,
The storage element according to any one of claims 1 to 5, wherein the second conductive member is a current collector. A storage device comprising a storage element having an electrode body, wherein
And a first conductive member and a second conductive member disposed in a path of current flowing through the electrode body and joined to each other,
The first conductive member and the second conductive member have a first caulking joint portion formed with a concavo-convex structure in which a first portion of either one protrudes toward a second portion of the other,
The first caulking joint is formed by a concavo-convex structure in which a third part of one of the first part and the second part is projected toward a fourth part of the other. Power storage device having a caulking junction.