JP2019067595A - Power storage element - Google Patents

Abstract

To provide a power storage element capable of protecting a collector.SOLUTION: In a power storage element 10 including an electrode body 400 and a positive electrode collector 500, the positive electrode collector 500 has an electrode body side arrangement part 520 being joined to the electrode body 400, and an insulating cover member 530 placed on the first surface 521 of the electrode body side arrangement part 520 on the electrode body 400 side, and on the second surface 522 of the electrode body side arrangement part 520 on the opposite side to the first surface 521. The cover member 530 has a first cover part 531 placed on the first surface 521, and in which a first opening 531a passing the juncture 550 of the electrode body side arrangement part 520 and the electrode body 400 is formed, and a second cover part 532 placed on the second surface 522, and in which a second opening 532a is formed at a position facing the first opening 531a.SELECTED DRAWING: Figure 4

Description

  The present invention relates to an electric storage device provided with an electrode body and a current collector.

  Conventionally, in a storage element including an electrode body and a current collector, a configuration in which a current collector is joined to the electrode body is widely known (see, for example, Patent Document 1).

JP, 2009-32640, A

  However, in the above-mentioned conventional storage element, since the current collector is not protected, the current collector may be damaged by external vibration or impact. Since damage to the current collector may lead to problems such as damage to the electrode body, a configuration for protecting the current collector is desired.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a storage element capable of protecting a current collector.

  In order to achieve the above object, a storage element according to an aspect of the present invention is a storage element including an electrode body and a current collector, and the current collector is arranged on the electrode body side to be joined to the electrode body. And an insulating cover member disposed on a second surface opposite to the first surface of the electrode body side arrangement portion, and a first surface of the electrode body side arrangement portion and the electrode body side arrangement portion. The cover member is disposed on the first surface, and is disposed on the second surface and a first cover portion in which a first opening through which a joint portion between the electrode body side arrangement portion and the electrode body passes is formed. And a second cover portion in which a second opening is formed at a position facing the first opening.

  According to this, in the storage element, the current collector is the insulating cover member disposed on the first surface on the electrode body side of the electrode body side arrangement portion joined to the electrode body and the second surface on the opposite side thereof have. Thus, by arranging the cover members on both sides of the electrode body side arrangement portion of the current collector, the cover member protects the electrode body side arrangement portion by the cover member even when the electrode body side arrangement portion receives vibration or impact from the outside. be able to. However, in this case, when joining the electrode body side arrangement portion and the electrode body, the cover member may be an obstacle. For this reason, the first cover portion disposed on the first surface of the cover member is provided with the first opening through which the joint portion between the electrode body side arrangement portion and the electrode body penetrates, and is disposed on the second surface The second cover is formed with a second opening at a position facing the first opening. As described above, since the opening is formed at a position corresponding to the bonding portion between the electrode body side placement portion and the electrode body of the cover member, the cover member is formed when the electrode body side placement portion and the electrode body are bonded. It can suppress being in the way. As described above, it is possible to protect the current collector while suppressing the occurrence of a defect when bonding the current collector and the electrode body.

  The first opening may have a smaller opening area than the second opening.

  According to this, in the cover member, the first opening of the first cover portion has a smaller opening area than the second opening of the second cover portion. Thus, by enlarging the second opening of the second cover portion on the outer surface side of the electrode body side arrangement portion, an instrument for joining the electrode body side arrangement portion and the electrode body is disposed in the second opening portion. Thus, it is possible to easily perform the bonding operation while suppressing the cover member from getting in the way. This makes it possible to protect the current collector while suppressing the occurrence of a defect when joining the current collector and the electrode body.

  Further, the electrode body side arrangement portion may have a convex portion arranged in the first opening.

  According to this, in the current collector, the electrode body side disposition portion has the convex portion disposed in the first opening portion of the first cover portion. As described above, by arranging the convex portion of the electrode body side arrangement portion in the first opening portion of the first cover portion, the convex portion is brought into contact with the electrode body when the electrode body side arrangement portion and the electrode body are joined. Can be performed to prevent the cover member from being in the way. This makes it possible to protect the current collector while suppressing the occurrence of a defect when joining the current collector and the electrode body.

  Further, the current collector further includes a cover plate disposed at a position sandwiching the electrode body with the first surface, a third surface which is a surface on the electrode body side of the cover plate, and the cover plate. And an insulating contact plate holding member disposed on the fourth surface which is a surface opposite to the third surface, the contact plate holding member being disposed on the third surface, and the contact plate A first holding portion provided with a third opening through which a joint between the electrode and the electrode body passes, and a fourth opening disposed at the fourth surface and facing the third opening And a second holding unit.

  According to this, the current collector further includes the cover plate, the third surface on the electrode body side of the cover plate, and the insulating contact plate holding member disposed on the fourth surface opposite to the contact plate. ing. As described above, by sandwiching and holding the backing plate by the contact plate holding member, the backing plate, which is a small component, can be easily handled. In addition, since the contact plate holding member is disposed between the electrode body and the contact plate by arranging the contact plate holding members on both sides of the contact plate, the contact plate is made of the electrode member by external vibration or impact. Damage can be suppressed. However, in this case, when the backing plate and the electrode body are joined, the backing plate holding member may be in the way. Therefore, in the first holding portion disposed on the third surface of the contact plate holding member, the third opening through which the joint portion between the contact plate and the electrode body penetrates is formed, and is disposed on the fourth surface A fourth opening is formed in the second holding portion at a position facing the third opening. As described above, since the opening is formed at a position corresponding to the joining portion between the backing plate and the electrode body of the backing plate holding member, when the backing plate and the electrode body are joined, the backing plate holding member It can suppress being in the way. As described above, it is possible to protect the current collector while suppressing the occurrence of problems caused by the backing plate when the current collector and the electrode body are joined.

  The third opening may have a smaller opening area than the fourth opening.

  According to this, in the contact plate holding member, the third opening of the first holding portion has a smaller opening area than the fourth opening of the second holding portion. In this manner, by enlarging the fourth opening of the second holding portion on the inner surface side of the backing plate, a device for joining the backing plate and the electrode body can be disposed in the fourth opening, The joining operation can be easily performed by suppressing the plate holding member from being in the way. Thereby, protection of a collector can be aimed at, suppressing generation | occurrence | production of the malfunction resulting from the backing plate at the time of joining a collector and an electrode body.

  The present invention can not only be realized as such a storage element, but also as a current collector (electrode body side arrangement portion, cover member, backing plate and contact plate holding member) included in the storage element. Can.

  According to the storage element of the present invention, the current collector can be protected.

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 a perspective view and sectional drawing which show the structure of the terminal side arrangement | positioning part of the positive electrode collector concerning embodiment, the electrode body side arrangement | positioning part, and a cover member. It is the perspective view and sectional drawing which show the structure of the board | substrate unit of the positive electrode collector which concerns on embodiment. It is sectional drawing which shows the structure in the state by which the positive electrode collector which concerns on embodiment is joined to the electrode body. It is the perspective view and sectional drawing which show the structure of the board | plate unit which concerns on the modification of embodiment.

  Hereinafter, an energy storage device according to an embodiment (and a modification thereof) 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 axis direction of the electrode body 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, or the alignment direction of the legs (electrode side arrangement portion) in one current collector is defined as the Y axis direction. Do. Further, the direction in which the container body and the lid of the storage element are aligned, the longitudinal direction of the short side surface of the container, or the extending direction of the leg portion (electrode body side arrangement 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 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 kind, Various things 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 a cross-sectional shape of the electrode body 400, but a circular shape, an elliptical shape, or the like may be used.

  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.

  Here, as shown in FIG. 3, the positive electrode current collector 500 has a terminal side placement portion 510, an electrode body side placement portion 520, a cover member 530, and a contact plate unit 540. Hereinafter, these configurations will be described in detail using FIGS. 4 to 6. FIG. 4 is a perspective view and a cross-sectional view showing the configuration of the terminal side disposition portion 510, the electrode body side disposition portion 520, and the cover member 530 of the positive electrode current collector 500 according to the present embodiment. FIG. 5 is a perspective view and a cross-sectional view showing the configuration of the contact plate unit 540 of the positive electrode current collector 500 according to the present embodiment. FIG. 6 is a cross-sectional view showing the configuration in a state where the positive electrode current collector 500 according to the present embodiment is joined to the electrode assembly 400. In addition, since the positive electrode current collector 500 and the negative electrode current collector 600 have the same configuration, in the following, the configuration of the positive electrode current collector 500 will be described, and the configuration of the negative electrode current collector 600 will be described. Is omitted.

[2 Description of Configurations of Terminal-Side Arrangement Portion 510, Electrode Body-Side Arrangement Portion 520, and Cover Member 530 of Positive Electrode Current Collector 500]
First, the configurations of the terminal side placement portion 510, the electrode body side placement portion 520, and the cover member 530 of the positive electrode current collector 500 will be described in detail with reference to FIGS. 4 and 6. 4A is a perspective view showing the configuration of the terminal side arranging portion 510, the electrode body side arranging portion 520, and the cover member 530, and FIG. 4B is an IVb in FIG. 4A. -FIG.4 (c) is sectional drawing which shows the structure in the IVc-IVc cross section in (a) of FIG. 4 which shows the structure in -IVb cross section.

  As shown in FIG. 4, the terminal-side placement portion 510 is a base of the positive electrode current collector 500 disposed on the positive electrode terminal 200 side (upper side, Z-axis direction plus side) of the positive electrode current collector 500. Specifically, terminal-side arrangement portion 510 is a flat and rectangular portion parallel to the XY plane in which circular opening 511 is formed, and is connected electrically and mechanically to positive electrode terminal 200 (joining ).

  The electrode body side arrangement portion 520 is a leg portion of the positive electrode current collector 500 disposed on the electrode body 400 side (lower side, negative side in the Z-axis direction) of the positive electrode current collector 500. Specifically, the electrode body side arrangement portion 520 is a long and flat plate shape extending from the end on both sides in the X axis direction and both sides in the Y axis direction of the terminal side arrangement portion 510 toward the Z axis direction minus side. And is electrically and mechanically connected (joined) to the electrode body 400. That is, as shown in FIG. 6, the two electrode body side arrangement parts 520 are joined to the outside of the two opposing flat focusing parts 411 of the positive electrode focusing parts 410 of the electrode body 400, respectively.

  Here, the two electrode body side arrangement parts 520 are arranged in parallel to the XZ plane and arranged side by side in the Y-axis direction. Specifically, each electrode body side arrangement portion 520 is a first surface 521 that is a surface parallel to the XZ plane facing the positive electrode focusing portion 410 (focusing portion 411) of the electrode body 400, and the first surface 521 And a second surface 522 which is a surface parallel to the opposite XZ plane. Further, on the first surface 521, a current collector convex portion 521a which is two circular convex portions aligned in the Z-axis direction is formed. The current collector convex portion 521 a is a convex portion disposed in a first opening 531 a of a cover member 530 described later, and has a shape corresponding to the first opening 531 a. Further, current collector concave portions 522a, which are two circular concave portions aligned in the Z-axis direction, are formed at positions on the second surface 522 facing the current collector convex portions 521a. The current collector concave portion 522a is a concave portion disposed in a second opening 532a of a cover member 530 described later, and has a diameter smaller than the outer diameter of the current collector convex portion 521a.

  The cover member 530 is an insulating member disposed on the first surface 521 on the electrode body 400 side of the electrode body side disposition portion 520 and on the second surface 522 opposite to the first surface 521 of the electrode body side disposition portion 520. It is. Specifically, the cover member 530 includes a first cover portion 531 disposed on the first surface 521 of the electrode body side disposition portion 520 and a second cover portion 532 disposed on the second surface 522 of the electrode body side disposition portion 520. And. Further, the cover member 530 further extends from both of the first cover portion 531 and the second cover portion 532 in a direction inclining with respect to both of them and in a direction along the electrode body 400. It has 533. That is, the first cover portion 531, the second cover portion 532, and the third cover portion 533 are disposed in each of the two electrode body side disposition portions 520.

  The first cover portion 531, the second cover portion 532 and the third cover portion 533 disposed in each of the electrode body side disposition portions 520 are integrally formed. For example, by bending one insulating sheet member, the cover member 530 including the first cover portion 531, the second cover portion 532 and the third cover portion 533 can be formed. The cover member 530 is made of, for example, an insulating material such as polycarbonate (PC), polypropylene (PP), polyethylene (PE), polyphenylene sulfide resin (PPS), polybutylene terephthalate (PBT), or ABS resin.

  Specifically, the first cover portion 531 is a long rectangular and flat plate extending in the Z-axis direction along the first surface 521 of the electrode body side arrangement portion 520 (in contact with the first surface 521). It is an area | region and the two 1st opening parts 531a located in a line with the Z-axis direction are formed. The first opening 531a is a circular through hole through which a joint 550 (see FIG. 6) between the electrode body side arrangement part 520 and the electrode body 400 passes. Further, the second cover portion 532 is a long rectangular and flat portion extending in the Z-axis direction along the second surface 522 of the electrode body side arrangement portion 520 (in contact with the second surface 522), , And two second openings 532a aligned in the Z-axis direction. The second opening 532a is a rectangular through hole formed at a position facing the first opening 531a.

  Here, the first opening 531a has a smaller opening area than the second opening 532a. Here, the opening area is the area in the opening when viewed from the Y-axis direction. That is, as viewed from the Y-axis direction, the first opening 531a is disposed at a position included in the second opening 532a. More specifically, when viewed from the Y-axis direction, the first opening 531a is included in the second opening 532a, the current collector convex portion 521a is included in the first opening 531a, and the current collector is The current collector concave portion 522a is disposed so as to be included inside the convex portion 521a.

  In addition, the third cover portion 533 is disposed so as to be inclined to the Y axis direction plus side or minus side from the edge on the X axis direction minus side of both the first cover portion 531 and the second cover portion 532. Two elongated rectangular and flat portions extending in the direction are formed to overlap each other. Specifically, two third cover parts 533 are arranged for two electrode body side arrangement parts 520, and the two third cover parts 533 are on the electrode body 400 side (minus side in the X-axis direction). The closer they are to the other, the more they are separated from each other.

[Description of Configuration of 3 Plate Unit 540]
Next, the configuration of the contact plate unit 540 will be described in detail using FIGS. 5 and 6. 5 (a) is a perspective view showing the structure of the corresponding plate unit 540, and FIG. 5 (b) is a cross-sectional view showing the structure at the Vb-Vb cross section in FIG. 5 (a). is there.

  As shown in FIGS. 5 and 6, the contact plate unit 540 includes a contact plate 541 and a contact plate holding member 542. The contact plate 541 is a member disposed at a position where the electrode body 400 is sandwiched by the first surface 521 of the electrode body side arrangement portion 520. Specifically, the backing plate 541 has two portions electrically and mechanically connected (bonded) to the inside of the two opposing flat focusing portions 411 of the positive electrode focusing portions 410 of the electrode assembly 400. It is a member having a substantially U-shaped (U-shaped) cross section. The material of the backing plate 541 is not particularly limited, but, for example, like the positive electrode current collector 500, it is a metal member formed of aluminum or an aluminum alloy. A backing plate is similarly disposed on the negative electrode side, and the material of the backing plate on the negative electrode side is also not particularly limited. For example, like the negative electrode current collector 600, it is made of copper or copper alloy Metal members.

  Here, the backing plate 541 is a third surface 541a which is a surface parallel to the XZ plane facing the positive electrode focusing portion 410 (focusing portion 411) of the electrode body 400, and an XZ plane opposite to the third surface 541a. And a fourth surface 541 c which is a parallel surface. Further, on the third surface 541a, a corresponding plate convex portion 541b which is a circular convex portion is formed. The corresponding plate convex portion 541 b is a convex portion which is disposed in a third opening 542 b of a corresponding plate holding member 542 described later, and has a shape corresponding to the third opening 542 b. Further, at a position of the fourth surface 541c facing the contact plate convex portion 541b, a contact plate concave portion 541d which is a circular recess is formed. The corresponding plate concave portion 541 d is a concave portion disposed in the fourth opening 542 d of the corresponding plate holding member 542 described later, and has a diameter smaller than the outer diameter of the corresponding plate convex portion 541 b.

  The backing plate 541 includes two portions having a third surface 541a and a fourth surface 541c corresponding to the two focusing portions 411. The two portions extend in the Y-axis direction and have a rectangular shape. A flat plate-like contact plate connecting portion 541e connects the members together to form a member having a substantially U-shaped cross section. For example, by bending a single plate member made of metal, the touch plate 541 of the one piece can be formed. Further, corresponding to the positions of the two current collector convex portions 521a aligned in the Z-axis direction of the electrode body side arrangement portion 520, two contact plates 541 are arranged in the Z-axis direction.

  The corresponding plate holding member 542 is disposed on a third surface 541a which is a surface on the electrode body 400 side of the backing plate 541 and a fourth surface 541c which is a surface on the opposite side to the third surface 541a of the backing plate 541. It is an insulating member. Specifically, the contact plate holding member 542 includes a first holding portion 542a disposed on the third surface 541a of the backing plate 541 and a second holding portion 542c disposed on the fourth surface 541c of the backing plate 541. Have.

  Specifically, the contact plate holding member 542 has two first holding portions 542a corresponding to the two third surfaces 541a of one backing plate 541, and these two first holding portions 542a is connected by a first connecting portion 542e to form a section having a substantially U-shaped cross section. Similarly, the contact plate holding member 542 has two second holding portions 542 c corresponding to two fourth surfaces 541 c of one backing plate 541, and the two second holding portions 542 c The portions are connected by the second connecting portion 542 f to form a section having a substantially U-shaped cross section. Then, the two first holding portions 542a and the two second holding portions 542c are arranged in pairs in the Z-axis direction, and are connected by one third connecting portion 542g, so that a single contact plate holding member is obtained. 542 is formed. For example, the single contact sheet holding member 542 can be formed by bending a single insulating sheet member. As described above, the contact plate unit 540 is configured such that the contact plate holding member 542 holds the two contact plates 541 and is integrated. The corresponding plate holding member 542 is made of, for example, an insulating material such as PC, PP, PE, PPS, PBT, or ABS resin.

  More specifically, the first holding portion 542a is a rectangular and flat portion disposed along (in contact with the third surface 541a) the third surface 541a of the backing plate 541, and the third opening A portion 542b is formed. The third opening 542 b is a circular through hole through which a joint 550 (see FIG. 6) between the backing plate 541 and the electrode assembly 400 passes. The second holding portion 542c is a rectangular and flat portion disposed along the fourth surface 541c of the backing plate 541 (in contact with the fourth surface 541c), and the fourth opening 542d is formed. It is done. The fourth opening 542 d is a rectangular through hole formed at a position facing the third opening 542 b.

  Here, the third opening 542 b has a smaller opening area than the fourth opening 542 d. That is, as viewed from the Y-axis direction, the third opening 542 b is disposed at a position included in the fourth opening 542 d. More specifically, as viewed in the Y-axis direction, the fourth opening 542 d includes the third opening 542 b, and the third opening 542 b includes the contact plate projection 541 b, and the contact plate projection The inside of the plate 541 b is arranged so as to include the abutting plate recess 541 d.

  With the above configuration, as shown in FIG. 6, the current collector convex portion 521 a of the electrode body side arrangement portion 520, the converging portion 411 of the positive electrode converging portion 410 of the electrode body 400, and the contact plate convex portion of the contact plate 541. A junction 550 is formed by joining with 541 b. Specifically, resistance welding is performed in a state in which the current collector convex portion 521a and the contact plate convex portion 541b pass through the first opening 531a and the third opening 542b and abut on the focusing portion 411, and the focusing is performed. Bonding is performed together with the portion 411 to form a bonding portion 550. In addition, since the second opening 532a and the fourth opening 542d are formed at the position where the joint portion 550 of the second cover portion 532 and the second holding portion 542c is formed, the second cover portion 532 and the fourth The bonding portion 550 is exposed from the second holding portion 542 c.

[4 Description of effect]
As described above, according to the storage element 10 according to the embodiment of the present invention, the positive electrode current collector 500 is the first surface 521 of the electrode body side arrangement portion 520 joined to the electrode body 400 on the electrode body 400 side. And an insulating cover member 530 disposed on the opposite second surface 522. As described above, by arranging the cover members 530 on both surfaces of the electrode body side arrangement portion 520 of the positive electrode current collector 500, even when the electrode body side arrangement portion 520 receives vibration or impact from the outside, the cover member 530 Body placement 520 can be protected. However, in this case, the cover member 530 may get in the way when the electrode body side arrangement part 520 and the electrode body 400 are joined. Therefore, in the first cover portion 531 of the cover member 530 disposed on the first surface 521, a first opening 531a through which the joint portion 550 of the electrode body side arrangement portion 520 and the electrode body 400 penetrates is formed. The second cover 532 disposed on the second surface 522 is provided with a second opening 532 a at a position facing the first opening 531 a. Thus, since the opening is formed at a position corresponding to the bonding portion 550 between the electrode body side placement portion 520 and the electrode body 400 of the cover member 530, the electrode body side placement portion 520 and the electrode body 400 are bonded. In this case, it can be suppressed that the cover member 530 gets in the way. In addition, by arranging the cover member 530, it is possible to selectively contact the parts to be joined of the electrode body side arrangement part 520 and the electrode body 400. For this reason, when joining by resistance welding is performed, the cover member 530 is prevented from being energized in an unintended path, so that the risk of occurrence of spatter can be suppressed. As described above, it is possible to protect the positive electrode current collector 500 while suppressing the occurrence of a defect when the positive electrode current collector 500 and the electrode assembly 400 are joined.

  In the cover member 530, the first opening 531a of the first cover 531 has a smaller opening area than the second opening 532a of the second cover 532. Thus, by enlarging the second opening 532a of the second cover 532 on the outer surface side of the electrode body side arrangement portion 520, a device for joining the electrode body side arrangement portion 520 and the electrode body 400 to the second opening Since it can arrange | position in the part 532a, it can suppress that the cover member 530 becomes obstructive, and can perform joining operation easily. In addition, when joining by resistance welding, by making the first opening 531a of the first cover 531 on the electrode body 400 side of the electrode body side arrangement portion 520 smaller, it is possible to conduct electricity in unintended paths. Since the suppression is performed, it is possible to suppress the risk of spattering. Thereby, the positive electrode current collector 500 can be protected while suppressing the occurrence of a defect when the positive electrode current collector 500 and the electrode body 400 are joined.

  In addition, in the positive electrode current collector 500, the electrode body side arrangement portion 520 includes a current collector convex portion 521a disposed in the first opening 531a of the first cover portion 531. As described above, when the current collector convex portion 521 a of the electrode body side arrangement portion 520 is disposed in the first opening 531 a of the first cover portion 531, the electrode body side arrangement portion 520 and the electrode body 400 are joined. Since the current collector convex portion 521a can be brought into contact with the electrode body 400 to perform the bonding operation, the cover member 530 can be prevented from being an obstacle. Further, in the case of joining by resistance welding, since a current path can be formed through the current collector convex portion 521a, it is possible to conduct electricity through the intended path, and to suppress the risk of occurrence of spattering. it can. Thereby, the positive electrode current collector 500 can be protected while suppressing the occurrence of a defect when the positive electrode current collector 500 and the electrode body 400 are joined.

  Further, by providing the third cover portion 533 along the electrode body 400, the electrode body 400 can be protected against external vibration and impact. In addition, the third cover portion 533 can restrict movement of the electrode body 400 in the container 100. Furthermore, since two third cover portions 533 extended from both the first cover portion 531 and the second cover portion 532 are provided and the two third cover portions 533 are connected, the cover member 530 is used. The cover member 530 can be fixed to the electrode body side arrangement part 520 in a state in which the electrode body side arrangement part 520 is sandwiched.

  In addition, the positive electrode current collector 500 further includes a contact plate 541, a third surface 541a on the electrode body 400 side of the contact plate 541, and a fourth contact surface 541c on the opposite side thereof. And a member 542. As described above, by sandwiching and holding the backing plate 541 with the contact plate holding member 542, the backing plate 541 which is a small component can be easily handled. Further, by arranging the contact plate holding members 542 on both surfaces of the contact plate 541, the contact plate holding member 542 is disposed between the electrode body 400 and the contact plate 541, so that the contact is caused by external vibration or impact. It is possible to prevent the plate 541 from damaging the electrode assembly 400. However, in this case, when the backing plate 541 and the electrode assembly 400 are joined, the backing plate holding member 542 may be an obstacle. Therefore, in the first holding portion 542a disposed on the third surface 541a of the contact plate holding member 543, the third opening 542b through which the joint portion 550 of the touch plate 541 and the electrode body 400 penetrates is formed. In the second holding portion 542c disposed on the fourth surface 541c, a fourth opening 542d is formed at a position facing the third opening 542b. As described above, since the opening is formed at a position corresponding to the joint portion 550 of the contact plate 541 and the electrode assembly 400 of the contact plate holding member 542, when the contact plate 541 and the electrode assembly 400 are joined. It is possible to suppress the contact plate holding member 542 from becoming an obstacle. Further, by arranging the contact plate holding member 542, the portions of the backing plate 541 and the electrode body 400 to be joined can be selectively brought into contact with each other. For this reason, when joining by resistance welding is performed, the plate holding member 542 suppresses current flow to an unintended path, so that the risk of occurrence of spatter can be suppressed. As described above, protection of the positive electrode current collector 500 can be achieved while suppressing occurrence of a defect due to the backing plate 541 when the positive electrode current collector 500 and the electrode assembly 400 are bonded.

  Further, in the contact plate holding member 542, the third opening 542b of the first holding portion 542a has a smaller opening area than the fourth opening 542d of the second holding portion 542c. Thus, by enlarging the fourth opening 542 d of the second holding portion 542 c on the inner surface side of the backing plate 541, an instrument for joining the backing plate 541 and the electrode assembly 400 into the fourth opening 542 d Since it can arrange, it can control that contact plate holding member 542 gets in the way, and can do junction work easily. Further, in the case of joining by resistance welding, by making the third opening 542 b of the first holding portion 542 a on the electrode body 400 side of the backing plate 541 smaller, it is possible to further suppress the conduction in the unintended path. Therefore, the risk of spattering can be suppressed. Thereby, protection of the positive electrode current collector 500 can be achieved while suppressing occurrence of a defect due to the backing plate 541 when the positive electrode current collector 500 and the electrode assembly 400 are joined.

  Since the negative electrode side also has the same configuration as that of the positive electrode side, the same effect can be obtained.

[Description of Modification of Fifth Embodiment]
(Modification)
Next, modifications of the above embodiment will be described. FIG. 7 is a perspective view and a cross-sectional view showing a configuration of a contact plate unit 560 according to a modification of the present embodiment. The same figure corresponds to FIG. That is, (a) of FIG. 7 is a perspective view showing a configuration of the corresponding plate unit 560, and (b) of FIG. 7 is a cross-sectional view showing a configuration in a VIIb-VIIb cross section in (a) of FIG. is there.

  As shown in FIG. 7, the abutting plate unit 560 in the present modification has an abutting plate holding member 562 instead of the abutting plate holding member 542 of the abutting plate unit 540 in the above embodiment. The other configuration of this modification is the same as that of the above embodiment, and the detailed description will be omitted.

  Here, the abutting plate unit 560 in this modification is formed by insert molding. That is, the backing plate 541 is integrally molded with the backing plate holding member 562 by insert molding. Therefore, the contact plate holding member 562 is a resin member formed of insertable resin. For example, the first holding portion 562 a and the fourth opening 562 d in which the third opening 562 b is formed similar to the contact plate holding member 542 by disposing a mold around the backing plate 541 and injecting a resin. The second holding portion 562c, the first connecting portion 562e, the second connecting portion 562f, and the third holding portion 562g may be formed.

  In addition, as a resin used for the corresponding plate holding member 562, for example, PP, PE, PPS, PBT, a phenol resin, etc. may be mentioned, but not only resin resins made of one type of resin material but plural resin materials A combination, a combination of a resin material and an elastomer material, or a combination of a resin material with a particulate or fibrous inorganic material may be used.

  As described above, according to the storage element 10 of the present modification, the same effect as that of the above embodiment can be obtained. In particular, in the above embodiment, it may be difficult to form the contact plate holding member 542 with the contact plate 541 with high accuracy, but in the present modification, the contact plate unit 560 is formed by insert molding. Therefore, the contact plate holding member 562 can be easily and precisely formed.

  In the same manner, the electrode body side arrangement portion 520 may be integrally formed with the cover member 530 by insert molding also for the electrode body side arrangement portion 520 and the cover member 530.

(Other modifications)
As mentioned above, although the electrical storage element 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 electrode body side arrangement portion 520 of the positive electrode current collector 500, the positive electrode focusing portion 410 of the electrode body 400, and the backing plate 541 are joined by resistance welding. However, the method of bonding these members is not limited to resistance welding, and may be caulking bonding such as laser welding, ultrasonic bonding, clinch bonding, or the like.

  Further, in the embodiment and the modification thereof, the first cover portion 531 of the cover member 530, the second cover portion 532 and the third cover portion 533 are integrally formed. However, any part of the first cover portion 531, the second cover portion 532 and the third cover portion 533 may be configured as separate members.

  Further, in the above-described embodiment and the modification thereof, in the cover plate 541, two portions having the third surface 541a and the fourth surface 541c are integrally formed by being connected by the contact plate connecting portion 541e. . However, the two parts having the third surface 541 a and the fourth surface 541 c may be configured as separate members.

  Moreover, in the said embodiment and its modification example, it was decided that two sets of two 1st holding parts and two 2nd holding parts are put in order, and the said board holding member is connected by the 3rd joining part. However, the two first holding portions and the two second holding portions may be configured as separate members. Further, in the contact plate holding member, the two first holding portions are connected by the first connecting portion, and the two second holding portions are connected by the second connecting portion. However, the two first holding portions may be separate members, and the two second holding portions may be separate members.

  Further, in the above-described embodiment and the variation thereof, it is assumed that two bonding portions 550 are formed in both of the two electrode body side placement portions 520. However, the number of bonding portions 550 formed in the electrode body side arrangement portion 520 is not particularly limited. In addition, the bonding portion 550 may be formed only in one of the two electrode body side placement portions 520.

  In the above embodiment and its modification, the current collector convex portion 521a, the current collector concave portion 522a, the first opening 531a, the contact plate convex portion 541b, the contact plate concave portion 541d, and the third opening It had circular shape seeing from the Y-axis direction. However, the shape of these portions is not particularly limited as long as the junctions 550 can be formed. Further, the shape of the bonding portion 550 is not particularly limited.

  Further, in the above-described embodiment and its modification, in the cover member 530, the first opening 531a has a smaller opening area than the second opening 532a. However, the first opening 531a may have an opening area larger than that of the second opening 532a. In the contact plate holding member 542, the third opening 542b has a smaller opening area than the fourth opening 542d. However, the third opening 542 b may have an opening area larger than that of the fourth opening 542 d.

  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. In addition, the shape of the electrode body 400 is not limited to the winding type, but 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 (a separator is twisted to form a rectangular electrode plate 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 the modification thereof, although the positive electrode current collector 500, the electrode assembly 400, and the backing plate 541 are joined, members other than these may be joined together. . Alternatively, the contact plate 541 (the target plate unit) may not be provided, and the positive electrode current collector 500 and the electrode assembly 400 may be bonded to form the bonding portion 550.

  Further, in the above-described embodiment and the modification thereof, the positive electrode current collector 500 and the electrode assembly 400 are bonded only at the bonding portion 550, but in addition to the bonding at the bonding portion 550, caulking bonding, etc. Bonding by other bonding methods may be performed. The bonding strength can be improved and the contact resistance can be reduced by performing bonding by another bonding method.

  Further, in the above embodiment and its modification, although both of the positive electrode current collector 500 and the negative electrode current collector 600 have the above configuration, the positive electrode current collector 500 and the negative electrode current collector 600 Only one of them may have the above configuration.

  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, but also the current collector (the positive electrode current collector 500 or the electrode body side arrangement portion of the negative electrode current collector 600 included in the storage element, a cover member, It can also be realized as a plate and a contact plate holding member).

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

10 storage element 400 electrode body 410 positive electrode focusing portion 500 positive electrode current collector 520 electrode body side arrangement portion 521 first surface 521 a current collector convex portion 522 second surface 530 cover member 531 first cover portion 531 a first opening 532 second Cover portion 532a Second opening portion 540, 560 Plate unit 541 Bent plate 541a Third surface 541b Plated convex portion 541c Fourth surface 542 562 Plate holding member 542a, 562a First holding portion 542b, 562b Third opening portion 542c, 562c second holding portion 542d, 562d fourth opening 550 joint portion 600 negative electrode current collector

Claims (5)

A storage element comprising an electrode body and a current collector,
The current collector is
An electrode body side arrangement portion joined to the electrode body;
It has an insulating cover member disposed on a first surface of the electrode body side disposition portion on the electrode body side, and a second surface opposite to the first surface of the electrode body side disposition portion.
The cover member is
A first cover portion disposed on the first surface and having a first opening portion through which a joint portion between the electrode body side arrangement portion and the electrode body penetrates;
And a second cover portion disposed on the second surface and having a second opening at a position facing the first opening. The storage element according to claim 1, wherein an opening area of the first opening is smaller than that of the second opening. The storage element according to claim 1, wherein the electrode body side arrangement part has a convex part arranged in the first opening. The current collector is further
A backing plate disposed at a position sandwiching the electrode body with the first surface;
A third surface which is a surface on the electrode body side of the backing plate, and an insulating contact plate holding member which is disposed on a fourth surface which is a surface opposite to the third surface of the backing plate. And
The contact plate holding member is
A first holding portion disposed on the third surface and having a third opening through which a joint portion between the backing plate and the electrode body penetrates;
The storage element according to any one of claims 1 to 3, further comprising: a second holding portion disposed on the fourth surface and having a fourth opening formed at a position facing the third opening. The storage element according to claim 4, wherein the third opening has an opening area smaller than that of the fourth opening.

Images