JP2019061880A - Power storage element - Google Patents

Abstract

To provide a power storage element that can suppress damage to an electrode body.SOLUTION: In a power storage element 10 including an electrode body 400 and a positive electrode current collector 700, the electrode body 400 includes a main body portion and an end portion to which the positive electrode current collector 700 is connected, and the positive electrode current collector 700 is disposed closer to the main body portion than the end portion and includes an opposing surface 742 facing the main body portion and a curved surface 770 curved in a dome shape from the opposing surface 742 to the opposite side to the main body portion.SELECTED DRAWING: Figure 4

Description

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

  2. Description of the Related Art Conventionally, a storage element having a configuration in which an electrode body and a current collector are provided and the current collector is connected to the electrode body is widely known. For example, Patent Document 1 includes a second flat plate portion including an electrode body and a current collection bar (current collector), and the current collection bar is disposed in the internal space of the electrode sheet of the electrode body, and a second flat plate portion Discloses a storage element having a wing portion which protrudes outward from the outer side and is joined to an electrode sheet.

JP 2003-249423 A

  However, in the configuration in which the current collector has the second flat plate portion inside the wing portion joined to the electrode body as in the above-mentioned conventional storage element, the electrode body is moved due to external vibration or impact. In this case, the second flat plate portion may enter inside the electrode body, and the corner portion of the second flat plate portion may damage the electrode body.

  This invention is made in view of the said subject, and it aims at providing the electrical storage element which can suppress that an electrode body is damaged.

  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 electrode body is connected to a main body portion and the current collector. An end portion, and the current collector is disposed closer to the main body portion than the end portion, and a facing surface facing the body portion, and a side opposite to the body portion from the facing surface And a curved surface which is curved in a dome shape.

  According to this, in the storage element, the current collector is disposed closer to the main body of the electrode body than the end of the electrode body, and an opposing surface facing the main body, and the main body of the electrode from the opposing surface And a curved surface which is curved in a dome shape toward the opposite side. Here, in the case where the current collector has a facing surface on the main body side with respect to the end portion of the electrode body, the facing surface may enter the inside of the electrode body due to external vibration or impact. There is a possibility that the corner of the may damage the electrode body. Therefore, the corner of the facing surface of the current collector is formed into a curved surface that is curved in a dome shape toward the opposite side to the main body of the electrode body. As a result, even if the opposing surface enters the inside of the electrode assembly due to external vibration or impact, the dome-shaped curved surface abuts on the electrode assembly, thereby suppressing damage to the electrode assembly. Can.

  Further, the curved surface is a curved surface formed at the position of an apex formed by the opposing surface and two adjacent surfaces extending from two adjacent sides of the opposing surface to the opposite side to the main body portion. You may

  According to this, in the current collector, the curved surface is a curved surface formed at the position of the vertex formed by the opposing surface and the two adjacent surfaces. That is, if the apexes of the three faces including the opposing face are sharp, the pointed apex may damage the electrode body if the opposing face enters the inside of the electrode body. Form a curved surface at the position of the apex. As a result, even if the opposing surface enters the inside of the electrode assembly due to external vibration or impact, the curved surface formed at the position of the apex abuts on the electrode assembly, thereby damaging the electrode assembly. Can be suppressed.

  Further, a space may be formed at the boundary between the two adjacent surfaces.

  According to this, in the current collector, a space is formed at the boundary between two adjacent surfaces adjacent to the opposite surface. Thus, the space is formed at the boundary portion between the two adjacent surfaces, so that the current collector is more flexible than in the case where the space is not formed at the boundary portion (the two adjacent surfaces are connected). Sex is high. For this reason, when the electrode body moves due to external vibration or impact, the current collector can absorb the movement of the electrode body, and damage to the electrode body can be suppressed.

  Further, the curved surface may have a first curved surface curved in a dome shape from the surface on the electrode terminal side of the facing surface to the opposite side to the main body.

  According to this, the current collector has a first curved surface which is curved in a dome shape from the surface on the opposing surface facing the electrode terminal toward the opposite side to the main body of the electrode body. Here, since the opposing surface of the current collector is disposed closer to the main body than the end of the electrode body, the opposing surface of the current collector is directed from the portion on the electrode terminal side toward the main body of the electrode assembly. It has a protruding shape. For this reason, since there is a possibility that the corner by the side of the electrode terminal of an opposite surface may damage an electrode body, the corner concerned concerned is curving in the shape of a dome, and the 1st curved surface is formed. As a result, even if the opposing surface enters the inside of the electrode assembly due to vibration or impact from the outside, the dome-shaped first curved surface abuts on the electrode assembly, thereby suppressing damage to the electrode assembly. can do.

  Further, the curved surface may have a second curved surface curved in a dome shape from the surface of the opposite surface opposite to the electrode terminal to the opposite side to the main body.

  According to this, the current collector has a second curved surface which is curved in a dome shape from the surface on the opposite surface opposite to the electrode terminal to the opposite side to the main body of the electrode body. Here, since the opposing surface of the current collector is disposed closer to the main body than the end of the electrode body, there is a risk that the corner on the opposing surface opposite to the electrode terminal may damage the electrode body. . For this reason, the corner on the opposite side of the electrode terminal of the opposite surface is curved in a dome shape to form a second curved surface. As a result, even if the opposing surface enters the inside of the electrode assembly due to external vibration or impact, the dome-shaped second curved surface abuts on the electrode assembly, thereby suppressing damage to the electrode assembly. can do.

  The present invention can not only be realized as such a storage element, but also can be realized as a current collector included in the storage element.

  According to the storage element of the present invention, damage to the electrode body can be suppressed.

It is a perspective view which isolate | separates and shows a container main body the structure of the electrical storage element which concerns on embodiment. It is a perspective view which shows the structure arrange | positioned inside the container main body of the electrical storage element which concerns on embodiment, separating a spacer. It is a perspective view which disassembles and shows each component arrange | positioned inside the container of the electrical storage element which concerns on embodiment. It is a perspective view which shows the structure of the positive electrode collector which concerns on embodiment. It is a perspective view which shows the structure of the spacer which concerns on embodiment. It is sectional drawing which shows the arrangement position of the electrode body which concerns on embodiment, a positive electrode collector, and a spacer. It is sectional drawing which shows the arrangement position of the electrode body which concerns on embodiment, a positive electrode collector, and a spacer.

  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, the manufacturing process, the order of manufacturing processes, and the like shown 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.

  In the following description and drawings of the embodiment, the arrangement direction of a pair of electrode terminals of a storage element, the arrangement direction of a pair of current collectors, the arrangement direction of a pair of spacers, and both ends of an electrode body (a pair of The arrangement direction of the active material layer non-forming portion, the winding axis direction of the electrode body, or the opposing direction of the short side surface of the container is defined as the X axis direction. In addition, the arrangement direction of the plurality of electrode bodies, the arrangement direction of the connection portion with the electrode body in one current collector, the opposing direction of the long side of the container, the short direction of the short side of the container, or the thickness direction of the container 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, the extending direction of the connection portion with the electrode body of the current collector, or the vertical direction 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). Although it may be considered that the Z-axis direction is not in the vertical direction depending on the mode of use, the Z-axis direction is hereinafter described as the vertical direction for the convenience of description. 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 configuration of a storage element 10 according to the present embodiment with the container main body 110 separated. Moreover, FIG. 2 is a perspective view which shows the structure arrange | positioned inside the container main body 110 of the electrical storage element 10 which concerns on this Embodiment by separating the spacers 500 and 600. FIG. That is, the figure shows the state after connecting the positive electrode current collector 700 and the negative electrode current collector 800 to the electrode assembly 400. FIG. 3 is an exploded perspective view showing each component disposed inside container 100 of power storage device 10 according to the present embodiment. That is, the figure shows a state before connecting the positive electrode current collector 700 and the negative electrode current collector 800 to the electrode assembly 400.

  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. In addition, although the rectangular parallelepiped (square) storage element 10 is illustrated in the present embodiment, the shape of the storage element 10 is not particularly limited, and may be a cylindrical shape, a long cylindrical shape, or the like. Or a laminate type storage element.

  As shown in FIG. 1, the storage element 10 includes a container 100 having a container body 110 and a lid 120, a positive electrode terminal 200, a positive electrode gasket 210, a negative electrode terminal 300, a negative electrode gasket 310, and an electrode assembly 400. Spacers 500 and 600 are provided. Further, as shown in FIGS. 2 and 3, the storage element 10 further includes a positive electrode current collector 700, a negative electrode current collector 800, and a clip 900.

  Although an electrolytic solution (nonaqueous electrolyte) is enclosed in the inside of the container 100, illustration is 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 gas discharge valve for releasing the pressure when the pressure in the container 100 is increased, a liquid injection unit for injecting an electrolyte into the container 100, or an electrode body 400. An insulating film or the like that wraps the like may be disposed.

[1.1 Description of Container 100, Positive Electrode Terminal 200, and Negative Electrode Terminal 300]
The container 100 is a rectangular parallelepiped (box-shaped) case composed of a container body 110 having a rectangular cylindrical bottom and a lid 120 which is a plate-like member closing the opening of the container body 110. Specifically, the lid 120 is a flat and rectangular wall extending in the X-axis direction, and is disposed on the plus side of the container body 110 in the Z-axis direction. The container body 110 has a flat bottom plate with a rectangular shape at the minus side in the Z-axis direction, a long flat plate with a flat plate and a rectangular shape at the side surfaces at both sides in the Y-axis direction, and a flat plate at the side surfaces at both sides in the X axis It has five walls of a rectangular short side wall.

  In the container 100, the electrode body 400, the spacers 500 and 600, the positive electrode current collector 700, the negative electrode current collector 800 and the like are accommodated inside the container body 110, and then the container body 110 and the lid 120 are welded or the like. This makes it possible to seal the inside. The material of the container body 110 and the lid 120 is not particularly limited, and may be, for example, a weldable metal such as stainless steel, aluminum, an aluminum alloy, iron, a plated steel plate, or a resin.

  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 Further, the positive electrode terminal 200 and the negative electrode terminal 300 are attached to a lid 120 disposed above the electrode assembly 400.

  Specifically, the positive electrode terminal 200 is crimped by inserting the protrusion 201 (see FIG. 7) into the through hole of the lid 120, the through hole of the positive electrode gasket 210, and the through hole 711 of the positive electrode current collector 700. Thus, the positive electrode gasket 210 and the positive electrode current collector 700 are fixed to the lid 120 together. Similarly, the negative electrode terminal 300 is fixed to the lid 120 together with the negative electrode gasket 310 and the negative electrode current collector 800. Thus, the positive electrode terminal 200 and the negative electrode terminal 300 are disposed on the positive side in the Z-axis direction of the positive electrode current collector 700 and the negative electrode current collector 800.

  The positive electrode gasket 210 is an insulating sealing member disposed between the lid 120 and the positive electrode terminal 200 and the positive electrode current collector 700. The positive electrode gasket 210 is made of, for example, a resin such as polycarbonate (PC), polypropylene (PP), polyethylene (PE), or polyphenylene sulfide resin (PPS). In addition, since the negative electrode gasket 310 also has the same configuration as that of the positive electrode gasket 210, the detailed description will be omitted.

[1.2 Description of Electrode Body 400]
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 assembly 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.

  Here, the electrode assembly 400 may be configured of one or more electrode assemblies, but in the present embodiment, the electrode assembly 400 is configured of a plurality of electrode assemblies. Specifically, the electrode assembly 400 includes two separate electrode assemblies, a first electrode assembly 410 and a second electrode assembly 420.

  That is, in the first electrode body 410, the active material layer non-formed portion of the end of the positive electrode plate is stacked and bundled into one at one end in the winding axial direction (the end on the positive side in the X-axis direction). A first positive electrode end 412 is provided. Further, in the first electrode body 410, the active material layer non-formed portion of the end of the negative electrode plate is stacked on the other end in the winding axial direction (the end on the negative side in the X axis direction) and bundled into one. The first negative electrode end 413 is provided. 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 50 to 70 sheets, for example, the first positive electrode side end portion 412 And the 1st negative electrode side end part 413 is formed. A portion of the first electrode body 410 other than the first positive electrode side end portion 412 and the first negative electrode side end portion 413 is referred to as a first electrode body main portion 411. That is, the first electrode body main part 411 is a portion of the first electrode body 410 in which the active material layer is formed on the base material layer. Similarly, in the second electrode body 420, the second electrode body main portion 421 on which the active material layer is formed, and the second positive electrode side in which the active material layer non-formed portion at the end of the positive electrode plate is bundled into one. An end portion 422 and a second negative electrode side end portion 423 in which an active material layer non-formed portion at the end portion of the negative electrode plate is bundled into one are provided.

  In the present embodiment, an oval shape is illustrated as a cross-sectional shape of the electrode body 400 (the first electrode body 410 and the second electrode body 420), but an elliptical shape, a circular shape, a polygonal shape, or the like may be used. Further, the shape of the electrode body 400 (the first electrode body 410 and the second electrode body 420) is not limited to the wound type, and may be a laminated type (stacked type) in which flat plate-like electrode plates are stacked. It may be in a bellows-like shape (strap-like shape).

[1.3 Description of Positive Electrode Current Collector 700 and Negative Electrode Current Collector 800]
The positive electrode current collector 700 is a current collector on the positive electrode side which is disposed on the positive side in the X-axis direction which is the side of the electrode assembly 400. Specifically, the positive electrode current collector 700 is disposed between the positive electrode side end of the electrode assembly 400 and the short side wall of the container body 110, and the positive electrode terminal 200 and the positive electrode side edge of the electrode assembly 400 are electrically It is a member provided with conductivity and rigidity to be connected. Similarly, the negative electrode current collector 800 is a current collector on the negative electrode side disposed on the negative side in the X-axis direction, which is the side of the electrode assembly 400. That is, the negative electrode current collector 800 is disposed between the negative electrode end of the electrode assembly 400 and the short side wall of the container body 110, and electrically connected to the negative electrode terminal 300 and the negative electrode end of the electrode assembly 400. Is a member provided with conductivity and rigidity.

  Specifically, the positive electrode current collector 700 is fixedly connected (joined) to the first positive electrode side end 412 of the first electrode body 410 and the second positive electrode side end 422 of the second electrode body 420. . More specifically, the first positive electrode side end 412 and the second positive electrode side end 422 are sandwiched between the positive electrode current collector 700 and the two clips 900 and joined by welding or the like. The clip 900 is a plate-like metal member. The positive electrode current collector 700 and the first positive electrode side end 412 and the second positive electrode side end 422 may be joined by any welding method such as laser welding, ultrasonic welding, resistance welding, etc. Other than welding, mechanical bonding such as caulking may be used.

  Similarly, the negative electrode current collector 800 is fixedly connected (joined) to the first negative electrode side end portion 413 of the first electrode body 410 and the second negative electrode side end portion 423 of the second electrode body 420. That is, the first negative electrode side end portion 413 and the second negative electrode side end portion 423 are sandwiched between the negative electrode current collector 800 and the two clips 900 and joined by welding or the like.

  In addition, the positive electrode current collector 700 and the negative electrode current collector 800 are fixedly connected (joined) to the lid 120. With this configuration, the first electrode body 410 and the second electrode body 420 are held (supported) in a state of being suspended from the lid 120 by the positive electrode current collector 700 and the negative electrode current collector 800, and vibration from the outside Vibration due to impact is suppressed.

  Although the material of the positive electrode current collector 700 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 800 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. The detailed description of the configurations of the positive electrode current collector 700 and the negative electrode current collector 800 will be described later.

  Here, when describing the positional relationship of members on the positive electrode side, such as the positive electrode current collector 700, the direction directed to the positive side in the X-axis direction is also referred to as a first direction. For example, it can be said that the positive electrode current collector 700 is disposed on the first direction side of the electrode body 400. In addition, since the member on the negative electrode side such as the negative electrode current collector 800 is disposed in the opposite direction to the member on the positive electrode side in the X-axis direction, when applied to the positional relationship of the members on the negative electrode side, the X axis direction The direction toward the minus side is the first direction. For example, like the positive electrode current collector 700, it can be said that the negative electrode current collector 800 is disposed on the first direction side of the electrode assembly 400. Further, a direction intersecting with the first direction (in the present embodiment, a direction directed to the plus side in the Z-axis direction) is also referred to as a second direction. For example, it can be said that the positive electrode terminal 200 and the negative electrode terminal 300 are disposed on the second direction side of the positive electrode current collector 700 and the negative electrode current collector 800.

[1.4 Description of spacers 500 and 600]
The spacer 500 is a spacer disposed on the positive side (first direction side) in the X-axis direction which is the side of the positive electrode current collector 700, and between the positive electrode current collector 700 and the short side wall portion of the container body 110. It is arranged to extend in the Z-axis direction (second direction) along the short side wall portion. The spacer 600 is a spacer disposed on the negative side in the X-axis direction, which is the side of the negative electrode current collector 800, and between the negative electrode current collector 800 and the short side wall portion of the container body 110. It is arranged to extend along the Z-axis direction. That is, the spacer 500 and the spacer 600 are disposed between both ends of the electrode body 400 and both side walls of the container 100 so as to sandwich the electrode body 400 from both ends in the X-axis direction.

  Here, the spacers 500 and 600 are formed of, for example, an insulating material such as polypropylene (PP), polyphenylene sulfide (PPS), polyethylene terephthalate (PET), ceramic, and a composite material thereof. That is, the spacers 500 and 600 insulate the container 100 from the electrode body 400, the positive electrode current collector 700 and the negative electrode current collector 800. In addition, the spacers 500 and 600 fill the space between the electrode body 400, the positive electrode current collector 700 and the negative electrode current collector 800, and the container 100 to obtain the electrode body 400, the positive electrode current collector 700 and the negative electrode current collector. 800 supports the container 100 against vibration. A detailed description of the configuration of the spacers 500 and 600 will be described later.

[2 Detailed Description of Positive Electrode Current Collector 700]
Next, the configuration of the positive electrode current collector 700 will be described in detail. Although the configuration of the positive electrode current collector 700 will be described below, the configuration of the negative electrode current collector 800 is the same as that of the positive electrode current collector 700. FIG. 4 is a perspective view showing the configuration of the positive electrode current collector 700 according to the present embodiment. Specifically, FIG. 4 (a) is an enlarged perspective view showing the positive electrode current collector 700 shown in FIG. 3, and FIG. 4 (b) is a positive electrode collection of FIG. 4 (a). FIG. 10 is a perspective view of the current collector 700 as viewed from the opposite side (rear side).

  As shown in FIG. 4, the positive electrode current collector 700 includes a terminal connecting portion 710, a first electrode connecting portion 720 and a second electrode connecting portion 730, a connecting portion 740, an intermediate portion 750, and an extending portion. And the 760.

  The terminal connection portion 710 is a base of the positive electrode current collector 700 connected to the positive electrode terminal 200. That is, the terminal connection portion 710 is a rectangular and flat portion disposed on the positive electrode terminal 200 side (upper side, positive side in the Z-axis direction) of the positive electrode current collector 700. Connected (joined). Note that, in the terminal connection portion 710, a circular through hole 711 into which the protrusion 201 of the positive electrode terminal 200 described above is inserted, and a through for rotation prevention into which the protrusion 211 (see FIG. 7) of the positive electrode gasket 210 is inserted. A hole 712 and a bead portion 713 for reinforcement are formed.

  The first electrode body connection portion 720 and the second electrode body connection portion 730 are portions connected to the electrode body 400. That is, the first electrode connection portion 720 and the second electrode connection portion 730 are portions disposed on the electrode body 400 side (lower side, the negative side in the Z-axis direction) of the positive electrode current collector 700. Electrically and mechanically. Specifically, the first electrode body connection portion 720 is a long and flat portion extending in the Z-axis direction (second direction), and is disposed on the first electrode body 410 side (minus side in the Y-axis direction) And connected to the first positive electrode end 412 of the first electrode body 410. Further, the second electrode body connection portion 730 is a long and flat portion extending in the Z-axis direction (second direction), and is disposed on the second electrode body 420 side (plus side in the Y-axis direction). It is connected to the second positive electrode side end 422 of the second electrode body 420.

  The connecting portion 740 is an end edge of the first electrode body connecting portion 720 on the electrode body 400 side (the negative side in the X-axis direction or the side opposite to the first direction), and an electrode body of the second electrode body connecting portion 730 It is a part that connects the edge on the 400 side. That is, the connecting portion 740 connects the end edges on the electrode body 400 side of the two connecting portions connected to the electrode body 400 of the positive electrode current collector 700, and is a long and flat wall extending in the Z-axis direction. It is a department. Thus, the connecting portion 740 is disposed at a position facing the electrode body 400 in the X-axis direction (first direction). In addition, a through hole may be formed in the connecting portion 740 in order to secure the injection property of the electrolytic solution.

  The middle portion 750 is a portion disposed between the connecting portion 740 and the terminal connection portion 710 and outside the connecting portion 740 (plus side in the X-axis direction or the first direction side). Here, the middle portion 750 includes a first middle portion 751 and a second middle portion 752.

  The first intermediate portion 751 is a rectangular and flat portion extending from the upper end portion (the end portion on the positive side in the Z-axis direction) of the connecting portion 740 to the positive side in the X-axis direction. That is, the first intermediate portion 751 is a wall portion parallel to the XY plane which is disposed on the plus side (the second direction side) in the Z-axis direction with respect to the first electrode connection portion 720 and the second electrode connection portion 730. . The second intermediate portion 752 is a rectangular and flat portion extending downward (Z-axis direction minus side) from the end of the terminal connection portion 710 on the plus side in the X-axis direction. That is, the second intermediate portion 752 is a wall portion parallel to the YZ plane disposed along the end in a position facing the end of the electrode body 400 in the X-axis direction (first direction).

  The extending portion 760 is a portion extending from the connecting portion 740 to the opposite side (the negative side in the Z-axis direction) to the terminal connecting portion 710 with respect to the first electrode connecting portion 720 and the second electrode connecting portion 730. It is. Specifically, the extending portion 760 is the outer side (the positive side in the X-axis direction or the first direction side) which is the first electrode body connecting portion 720 side and the second electrode body connecting portion 730 side than the connecting portion 740 And the Z axis direction minus side (opposite to the second direction) relative to the connecting portion 740. Here, the extending portion 760 includes a first extending portion 761 and a second extending portion 762.

  The first extending portion 761 is a rectangular and flat portion extending from the lower end portion (end portion on the negative side in the Z-axis direction) of the connecting portion 740 to the positive side in the X-axis direction. That is, the first extending portion 761 is parallel to the XY plane disposed on the Z axis direction minus side (opposite to the second direction) than the first electrode connection portion 720 and the second electrode connection portion 730. It is a wall. Further, the second extending portion 762 is a rectangular and flat portion extending downward (in the Z axis direction minus side) from an end portion on the X axis direction plus side of the first extending portion 761. That is, the second extending portion 762 is a wall parallel to the YZ plane disposed along the end in a position facing the end of the electrode body 400 in the X-axis direction (first direction). . Thus, the first extending portion 761 and the second extending portion 762 are the first electrode connecting portion 720 at the first intermediate portion 751 and the second intermediate portion 752 in the Z-axis direction (the second direction). And the second electrode body connecting portion 730.

  With such a configuration, the positive electrode current collector 700 is formed with a current collector concave portion 741 which is a concave portion having the connecting portion 740 as a bottom portion. That is, the current collector concave portion 741 has the first electrode body connection portion 720 and the second electrode body connection portion 730 which are two connection portions with the electrode body 400, the connection portion 740, the first intermediate portion 751, and It is a recess formed on the negative side in the X axis direction formed by the one extending portion 761.

  Furthermore, the positive electrode current collector 700 has a curved surface 770 curved in a dome shape from the opposing surface 742 which is the surface on the negative side in the X-axis direction of the connecting portion 740 to the positive side in the X-axis direction. Here, the opposing surface 742 is a surface which is disposed closer to the main body of the electrode assembly 400 than the end of the electrode assembly 400 and faces the main body of the electrode assembly 400 (see FIGS. 6 and 7). The end of the electrode assembly 400 means the first positive electrode end 412 and the second positive electrode end 422 or the positive side of the first positive electrode end 412 and the second positive electrode end 422 in the X-axis direction. At the end of the Further, the main body portion of the electrode body 400 is the first electrode body main portion 411 and the second electrode body main portion 421.

  The curved surface 770 is a surface that is curved in a dome shape from the opposing surface 742 toward the opposite side to the main body of the electrode assembly 400. That is, the curved surfaces 770 are four curved surfaces that are curved in a dome shape from the four corners of the facing surface 742 toward the plus side in the X-axis direction. Specifically, the curved surface 770 includes two opposing surfaces 742 and two adjacent surfaces extending from two adjacent sides of the opposing surface 742 to the opposite side to the main body of the electrode assembly 400 (for example, the first electrode assembly connecting portion 720 And a curved surface formed at the position of the vertex formed by the outer surface of the first intermediate portion 751). Thus, the curved surface 770 is not a planar (two-dimensional) curved surface formed by curving a flat surface in one direction, but a three-dimensional curved surface formed by curving a flat surface in two or more directions. It is a (three-dimensional) curved surface.

  Here, the curved surface 770 has two first curved surfaces 771 and 772 and two second curved surfaces 773 and 774. The first curved surfaces 771 and 772 are curved surfaces that are curved in a dome shape from the surface on the positive electrode terminal 200 side of the facing surface 742 toward the opposite side to the main body of the electrode assembly 400. That is, the first curved surface 771 is formed at the position of an apex formed by three surfaces of the facing surface 742 and the outer surface of the first electrode body connection portion 720 and the outer surface (two adjacent surfaces) of the first intermediate portion 751. Is a curved surface. In addition, the first curved surface 772 is formed at the position of an apex formed by three surfaces of the opposing surface 742 and the outer surface of the second electrode body connection portion 730 and the outer surface (two adjacent surfaces) of the first intermediate portion 751. Is a curved surface. Thus, the first curved surfaces 771 and 772 are curved surfaces formed at corners (apex portions) of three surfaces adjacent to each other.

  The second curved surfaces 773 and 774 are curved surfaces that are curved in a dome shape from the surface of the opposite surface 742 opposite to the positive electrode terminal 200 toward the opposite side to the main body of the electrode assembly 400. That is, the second curved surface 773 is at the position of the vertex formed by three surfaces of the facing surface 742 and the outer surface of the first electrode body connection portion 720 and the outer surface (two adjacent surfaces) of the first extending portion 761. It is a formed curved surface. In addition, the second curved surface 774 is located at an apex formed by three surfaces of the facing surface 742 and the outer surface of the second electrode body connection portion 730 and the outer surface (two adjacent surfaces) of the first extending portion 761. It is a formed curved surface. Thus, like the first curved surfaces 771 and 772, the second curved surfaces 773 and 774 are also curved surfaces formed at corners (apex portions) of three surfaces adjacent to each other.

  In addition, a space is formed at the boundary between the two adjacent faces described above. For example, when the two adjacent surfaces are the outer surface of the first electrode body connection portion 720 and the outer surface of the first intermediate portion 751, the space between the first electrode body connection portion 720 and the first intermediate portion 751 is a space 775. Is formed. The same is true for the other two adjacent faces. The curved surface 770 and the space at the boundary between two adjacent surfaces such as the space 775 can be formed by drawing a plate member or the like.

[Detailed Description of 3 Spacer 500]
Next, the configuration of the spacer 500 will be described in detail. Although the configuration of the spacer 500 will be described below, the configuration of the spacer 600 is the same as the configuration of the spacer 500. FIG. 5 is a perspective view showing the configuration of the spacer 500 according to the present embodiment. Specifically, FIG. 5 (a) is an enlarged perspective view showing the spacer 500 shown in FIGS. 2 and 3, and FIG. 5 (b) shows the spacer 500 of FIG. 5 (a). It is a perspective view at the time of seeing from the other side (the back side).

  As shown in FIG. 5, the spacer 500 includes a spacer main body 510 and spacer side walls 520 and 530. The spacer main body portion 510 is a plate-like portion parallel to the YZ plane extending in the Z-axis direction that constitutes the main body portion of the spacer 500, and has a plurality of projecting portions projecting to the negative side in the X-axis direction. Spacer side wall portions 520 and 530 are plate-like portions parallel to the XZ plane extending in the Z-axis direction constituting the side wall portion of spacer 500, and a protruding portion protruding inward in the Y-axis direction is formed. .

  Specifically, the spacer main body 510 includes a spacer first convex portion 511 and a spacer second convex portion 512. The spacer first convex portion 511 is a substantially rectangular parallelepiped protruding portion (convex portion) that protrudes to the negative side in the X-axis direction (the side opposite to the first direction) and extends in the Z-axis direction. In addition, on the back side (plus side in the X-axis direction) of the spacer first convex portion 511, a spacer first concave portion 511a recessed toward the minus side in the X-axis direction is formed. The spacer second convex portion 512 is a protruding portion (convex portion) that protrudes in the negative side in the X-axis direction and extends in the Y-axis direction, and on the back side (plus side in the X-axis direction) of the spacer second convex portion 512 A spacer second recess 512 a is formed to be recessed toward the negative side in the X-axis direction.

  Here, the spacer second convex portion 512 has a U-shaped (U-shaped) shape in which a central portion on the spacer first convex portion 511 side (plus side in the Z-axis direction) is recessed. As a result, it extends in the Y-axis direction surrounded by the spacer first convex portion 511 and the recessed portion of the spacer second convex portion 512 between the spacer first convex portion 511 and the spacer second convex portion 512. A rectangular spacer recess 513 is formed. The spacer first convex portion 511 is disposed to protrude into the current collector recess 741 of the positive electrode current collector 700, and the extended portion 760 of the positive electrode current collector 700 is disposed in the spacer recess 513. The detailed description of these configurations will be described later.

  The spacer side wall 520 has a spacer third convex portion 521, and the spacer side wall 530 has a spacer fourth convex portion 531. The spacer third convex portion 521 is a substantially rectangular parallelepiped protruding portion (convex portion) that protrudes to the Y axis direction plus side and extends in the Z axis direction. In addition, on the back side (the negative side in the Y-axis direction) of the spacer third convex portion 521, a spacer third concave portion 521a recessed toward the positive side in the Y-axis direction is formed. The spacer fourth convex portion 531 is a substantially rectangular parallelepiped protruding portion (convex portion) that protrudes to the negative side in the Y-axis direction and extends in the Z-axis direction. In addition, on the back side (plus side in the Y-axis direction) of the spacer fourth convex part 531, a spacer fourth concave part 531a recessed toward the minus side in the Y-axis direction is formed.

[4. Description of Arrangement Position of Electrode Body 400, Positive Electrode Current Collector 700, and Spacer 500]
Next, the arrangement positions of the electrode body 400, the positive electrode current collector 700, and the spacer 500 will be described in detail. Although the arrangement position of the positive electrode side (the electrode body 400, the positive electrode current collector 700, and the spacer 500) is described below, the positive electrode position of the negative electrode side (the electrode body 400, the negative electrode current collector 800, and the spacer 600) is also described. It is the same as the arrangement position on the side. 6 and 7 are cross-sectional views showing the arrangement positions of the electrode assembly 400, the positive electrode current collector 700, and the spacer 500 according to the present embodiment. Specifically, FIG. 6 is a cross-sectional view showing the configuration on the positive electrode side when the configuration shown in FIG. 1 is cut along the VI-VI cross section (plane parallel to the XY plane). FIG. 7 is a cross-sectional view showing the configuration on the positive electrode side when the configuration shown in FIG. 1 is cut along the VII-VII cross section (plane parallel to the XZ plane).

  As shown in FIG. 6, in the positive electrode current collector 700, the first electrode body connection portion 720 is in contact with the surface on the Y axis direction plus side of the first positive electrode side end portion 412 of the first electrode body 410. And the first positive electrode end 412. Specifically, the first electrode body connection portion 720 is joined to the first positive electrode side end 412 in a state where the first positive electrode side end 412 is sandwiched with the clip 900. Further, the second electrode body connection portion 730 is joined to the second positive electrode side end portion 422 in a state of being in contact with the surface on the negative side in the Y axis direction of the second positive electrode side end portion 422 of the second electrode body 420 There is. Specifically, the second electrode body connection portion 730 is joined to the second positive electrode side end 422 in a state where the second positive electrode side end 422 is sandwiched with the clip 900. With this configuration, the connecting portion 740 is between the first electrode body 410 and the second electrode body 420, that is, the first positive electrode side end portion 412 of the first electrode body 410 and the second positive electrode side of the second electrode body 420. It is disposed between the end 422.

  Further, the spacer first convex portion 511 protrudes toward the connecting portion 740 in the X-axis direction (first direction), and is disposed in the current collector concave portion 741. That is, the spacer first convex portion 511 is positioned between the first electrode connection portion 720 and the second electrode connection portion 730 and facing the first electrode connection portion 720 and the second electrode connection portion 730. Will be placed. With this configuration, the spacer first convex portion 511 is located between the first electrode body 410 and the second electrode body 420, that is, the first positive electrode side end portion 412 of the first electrode body 410 and the second electrode body 420. It is disposed between the two positive electrode end portions 422 (between the end portions of the two electrode bodies 400).

  Further, the spacer third convex portion 521 and the spacer fourth convex portion 531 are disposed between the container 100 and the end of the electrode assembly 400 and are disposed so as to protrude toward the end of the electrode assembly 400. Further, the spacer third convex portion 521 and the spacer fourth convex portion 531 are disposed on the side opposite to the positive electrode current collector 700 with respect to the end portion of the electrode body 400 and on the opposite side to the end portion of the electrode body 400 Has a recess. Specifically, the spacer third convex portion 521 is disposed between the long side wall portion on the negative side in the Y-axis direction of the container body 110 and the first positive electrode side end portion 412 of the first electrode body 410, and It is disposed so as to protrude toward the side end portion 412 in the Y-axis direction plus side. Further, the spacer third convex portion 521 is disposed on the opposite side of the first electrode body connection portion 720 with respect to the first positive electrode side end 412, and the spacer third convex portion 521 is provided on the opposite side to the first positive electrode side end 412. It has three recesses 521a. The same applies to the spacer fourth convex portion 531.

  Further, the spacer third convex portion 521 and the spacer fourth convex portion 531 are disposed to protrude along the edge of the first electrode body main portion 411 and the second electrode body main portion 421 on the plus side in the X-axis direction There is. Thereby, the movement of the electrode assembly 400 (the first electrode assembly 410 and the second electrode assembly 420) can be suppressed, so that the electrode assembly 400 can be prevented from being damaged even by external vibration or impact. Can.

  Further, as shown in FIG. 7, in the positive electrode current collector 700, the first intermediate portion 751 is formed on the spacer first convex portion 511 on the Z axis direction plus side (second direction side) of the spacer first convex portion 511. It is arranged facing each other. Further, the first extension portion 761 is disposed on the negative side in the Z-axis direction of the spacer first convex portion 511 (opposite to the second direction side) so as to face the spacer first convex portion 511. That is, the spacer first convex portion 511 is disposed between the first intermediate portion 751 and the first extending portion 761. Specifically, the spacer first convex portion 511 is disposed in a current collector concave portion 741 formed by the connecting portion 740, the first intermediate portion 751, and the first extending portion 761.

  Further, the second positive electrode side end portion 422 has a second positive electrode side upper end portion 422a at the upper portion and a second positive electrode side lower end portion 422b at the lower portion (see FIG. 3). It is joined to a portion between the second positive electrode side upper end portion 422a and the second positive electrode side lower end portion 422b (a central portion in the Z-axis direction of the second positive electrode side end portion 422). Similarly for the first positive electrode side end 412, the second electrode body connection portion 720 is between the first positive electrode side upper end 412a (see FIG. 3) and the first positive electrode side lower end 412b (see FIG. 3). It is joined to the site.

  In addition, the second intermediate portion 752 is disposed at a position facing the first positive electrode side end 412 and the second positive electrode side end 422 in the X-axis direction (first direction). It is disposed along the positive electrode end 422. Specifically, the second intermediate portion 752 is positioned to face the first positive electrode side upper end portion 412a and the second positive electrode side upper end portion 422a in the X-axis direction, the first positive electrode side upper end portion 412a and the second positive electrode side It is disposed along the upper end 422a.

  Similarly, for the second extension portion 762 and the spacer second convex portion 512, the second extension portion 762 and the spacer second protrusion 512 are disposed at positions facing the first positive electrode side end 412 and the second positive electrode side end 422 in the X axis direction (first direction). It is disposed along the one positive electrode end 412 and the second positive electrode end 422. Specifically, the second extending portion 762 and the spacer second convex portion 512 are located on the first positive electrode side at positions facing the first positive electrode side lower end portion 412b and the second positive electrode side lower end portion 422b in the X-axis direction. It arrange | positions along the lower end part 412b and the 2nd positive electrode side lower end part 422b.

  Thus, the second extending portion 762 and the spacer second convex portion 512 form the first electrode body connecting portion 720 and the second electrode body connection with the second intermediate portion 752 in the Z-axis direction (second direction). It is disposed at a position sandwiching the part 730. Specifically, the spacer second convex portion 512 is the first extension in the Z axis direction minus side (opposite to the second direction) than the first electrode connection portion 720 and the second electrode connection portion 730. It is disposed on the minus side in the Z-axis direction with respect to the provision portion 761 and the second extending portion 762.

  In addition, the second extending portion 762 is disposed in the spacer recess 513 opposed to the extending portion 760, so that the second intermediate portion 752 is disposed on the inner side (the negative side in the X-axis direction, the side opposite to the first direction). The surface and the inner surface of the second extending portion 762 and the spacer second convex portion 512 are disposed on the same plane (on the plane P1 in FIG. 7). Further, the surface of the second intermediate portion 752 on the outer side (plus side in the X-axis direction, the first direction side) and the surface on the outer side of the second extending portion 762 are on the same plane (on the plane P2 of FIG. It is arranged. Thus, the second intermediate portion 752 and the second extending portion 762 are disposed in contact with the same inner surface of the spacer main portion 510. Note that arranging on the same plane is not limited to arranging on the same plane completely, but some deviations due to processing errors or selecting an optimal plate thickness for the material, etc. are acceptable. Be done.

[5 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 700 is disposed closer to the main body of the electrode assembly 400 than the end of the electrode assembly 400 and is It has an opposing surface 742, and a curved surface 770 curved in a dome shape from the opposing surface 742 to the opposite side to the main body of the electrode assembly 400. Here, when the positive electrode current collector 700 has the facing surface 742 on the main body side than the end of the electrode body 400, the facing surface 742 enters the inside of the electrode body 400 due to external vibration or impact. Also, there is a possibility that the corner of the opposite surface 742 may damage the electrode assembly 400. Therefore, corner portions of the facing surface 742 of the positive electrode current collector 700 are formed on a curved surface 770 which is curved in a dome shape toward the opposite side to the main body portion of the electrode assembly 400. As a result, even if the opposing surface 742 enters the inside of the electrode assembly 400 due to external vibration or impact, the dome-shaped curved surface 770 abuts on the electrode assembly 400, thereby damaging the electrode assembly 400. Can be suppressed.

  In the positive electrode current collector 700, the curved surface 770 is a curved surface formed at the position of an apex formed by the facing surface 742 and the two adjacent surfaces. That is, when the apexes of the three surfaces including the opposing surface 742 are pointed, there is a possibility that the pointed apex may damage the electrode assembly 400 when the opposing surface 742 enters the inside of the electrode assembly 400. Therefore, the curved surface 770 is formed at the position of the apex. As a result, even if the opposing surface 742 enters the inside of the electrode assembly 400 due to external vibration or impact, the curved surface 770 formed at the position of the apex abuts on the electrode assembly 400. Can be suppressed from being damaged.

  In the positive electrode current collector 700, a space is formed at the boundary between two adjacent surfaces adjacent to the opposite surface 742. Thus, the space is formed at the boundary portion between the two adjacent surfaces, so that the positive electrode current collector 700 is formed more than in the case where the space is not formed at the boundary portion (the two adjacent surfaces are connected). Flexibility is high. For this reason, when the electrode assembly 400 moves due to vibration or impact from the outside, the positive electrode current collector 700 can absorb the movement of the electrode assembly 400, and the electrode assembly 400 can be prevented from being damaged. Further, when the plate-like member is bent, the curved surface 770 can be easily formed by forming the curved surface 770 at the position of the apex of the opposing surface 742 and the three adjacent surfaces. Space is formed at the boundary between two adjacent faces. That is, rather than forming the curved surface 770 at the position of the vertex when the two adjacent surfaces are connected, it is better to form the curved surface 770 at the position of the vertex while the space is formed at the boundary between the two adjacent surfaces. However, the positive electrode current collector 700 can be easily manufactured.

  In addition, the positive electrode current collector 700 has first curved surfaces 771 and 772 curved in a dome shape from the surface on the positive electrode terminal 200 side of the opposing surface 742 toward the opposite side to the main body of the electrode assembly 400. ing. Here, since the facing surface 742 of the positive electrode current collector 700 is disposed closer to the main body than the end of the electrode body 400, the positive electrode current collector 700 is a portion on the positive electrode terminal 200 side (second intermediate portion A facing surface 742 protrudes from the surface 752 toward the main body of the electrode assembly 400. For this reason, there is a possibility that the corner on the positive electrode terminal 200 side of the facing surface 742 may damage the electrode body 400, so the corner is curved in a dome shape to form the first curved surfaces 771 and 772. Thus, even if the opposing surface 742 enters the inside of the electrode assembly 400 due to vibration or impact from the outside, the dome-shaped first curved surfaces 771 and 772 abut the electrode assembly 400, so the electrode assembly 400 is formed. Can be suppressed from being damaged.

  In addition, from the surface of the opposite surface 742 opposite to the positive electrode terminal 200 of the positive electrode current collector 700, the second curved surface 773 and 774 curved in a dome shape is directed to the opposite side to the main body of the electrode assembly 400. Have. Here, since the opposing surface 742 of the positive electrode current collector 700 is disposed closer to the main body than the end of the electrode body 400, the corner on the opposite side of the opposing surface 742 of the opposing surface 742 is the electrode body 400. There is a risk of damage. For this reason, the corner part on the opposite side to the positive electrode terminal 200 of the opposing surface 742 is curved in a dome shape to form the second curved surfaces 773 and 774. As a result, even if the opposing surface 742 enters the inside of the electrode assembly 400 due to external vibration or impact, the dome-shaped second curved surfaces 773 and 774 abut the electrode assembly 400, so that the electrode assembly 400 is produced. Can be suppressed from being damaged.

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

[6 Description of Modifications]
As mentioned above, although the electrical storage element which concerns on embodiment of this invention was demonstrated, this invention is not limited to this embodiment. That is, it should be considered that the embodiment disclosed this time is 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, the curved surface 770 is a curved surface formed at the position of an apex formed by three surfaces of the opposing surface 742 and two adjacent surfaces adjacent to the opposing surface 742. Here, the three surfaces are not limited to flat surfaces. For example, any of the surfaces may be a curved surface, such as the facing surface 742 is a curved surface. Alternatively, all of the first electrode body connection portion 720, the second electrode body connection portion 730, the connection portion 740, the first intermediate portion 751, and the first extension portion 761 are curved surfaces, and they are spherical or oblong as a whole. The curved surface 770 may be formed by having the shape of a part. The same applies to the negative electrode side.

  In the above embodiment, a space is formed at the boundary between two adjacent surfaces adjacent to the opposite surface 742. However, the two adjacent surfaces may be connected and the space may not be formed. The same applies to the negative electrode side.

  Further, in the above embodiment, the positive electrode current collector 700 is provided with the extension portion 760 having the first extension portion 761 and the second extension portion 762. However, the positive electrode current collector 700 may not include the second extending portion 762, or may have the first extending portion 761 and the second extending portion 762 (that is, the extending portion 760). You may decide not to In the case where the positive electrode current collector 700 does not have the extended portion 760, the curved surface 770 may not have the two second curved surfaces 773 and 774. Similarly, the curved surface 770 may not have the two first curved surfaces 771 and 772. In other words, even if the curved surface 770 does not have any of the four curved surfaces of the two first curved surfaces 771 and 772 and the two second curved surfaces 773 and 774. Good. The same applies to the negative electrode side.

  Further, in the above embodiment, the positive electrode current collector 700 is joined to the end of the electrode body 400 in a state in which the end of the electrode body 400 is sandwiched with the clip 900. However, the positive electrode current collector 700 may be joined to the end of the electrode body 400 without the clip 900 being disposed. The same applies to the negative electrode side.

  Further, in the above embodiment, the connecting portion 740 connects the ends of the first electrode body connecting portion 720 and the second electrode body connecting portion 730 on the electrode body 400 side (the negative side in the X-axis direction). did. However, the connecting portions 740 are the end positions of the first electrode body connecting portion 720 and the second electrode body connecting portion 730 on the opposite side (plus side in the X-axis direction) to each other, or the center position in the X-axis direction Any position may be connected, such as connecting the two. That is, the connecting portion 740 connects the first electrode body connecting portion 720 and the second electrode body connecting portion 730, and the first positive electrode side end portion 412 of the first electrode body connecting portion 720 and the second electrode body connecting portion 730. And the portion disposed along the connection portion with the second positive electrode end 422. In addition, the said connection part is a joining part by the elongate welding etc. which extend in Z-axis direction. The same applies to the negative electrode side.

  Further, in the above embodiment, the spacer 500 is disposed on the side of the positive electrode current collector 700, and the spacer 500 has a plurality of convex portions and concave portions. However, the spacer 500 may not have some or all of these projections and recesses. For example, the spacer recess 513 in which the second extending portion 762 is disposed may not be formed in the spacer 500. Further, the spacer 500 may not be provided on the side of the positive electrode current collector 700. The same applies to the negative electrode side.

  Further, in the above embodiment, although both of the positive electrode current collector 700 and the negative electrode current collector 800 have the above configuration, the positive electrode current collector 700 or the negative electrode current collector 800 is not limited to the above. It may not have the 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.

  The present invention can not only be realized as such a storage element, but also can be realized as a current collector (a positive electrode current collector 700, a negative electrode current collector 800) included in the storage element.

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

DESCRIPTION OF SYMBOLS 10 Storage element 200 Positive electrode terminal 400 Electrode body 410 1st electrode body 411 1st electrode body main-body part 412 1st positive electrode side edge part 420 2nd electrode body 421 2nd electrode body main-body part 422 2nd positive electrode side edge part 700 Positive electrode collection Electric conductor 720 First electrode body connection portion 730 Second electrode body connection portion 740 Joint portion 742 Opposing surface 750 Intermediate portion 751 First intermediate portion 760 Extension portion 761 First extension portion 770 Curved surface 771, 772 First curved surface 773, 774 second curved surface 775 space

Claims (5)

A storage element comprising an electrode body and a current collector,
The electrode body has a main body and an end to which the current collector is connected,
The current collector is
An opposing surface disposed closer to the main body than the end and facing the main body;
A curved surface which is curved in a dome shape from the opposing surface to the opposite side to the main body portion. The curved surface is a curved surface formed at the position of an apex formed of the opposing surface and two adjacent surfaces extending from two adjacent sides of the opposing surface to the opposite side to the main body portion. A storage element according to claim 1. The storage element according to claim 2, wherein a space is formed at a boundary portion between the two adjacent surfaces. The electric storage according to any one of claims 1 to 3, wherein the curved surface has a first curved surface curved in a dome shape from the surface on the electrode terminal side of the facing surface to the opposite side to the main body. element. The said curved surface has a 2nd curved surface curved in the shape of a dome toward the opposite side to the said main-body part from the surface on the opposite side to the electrode terminal of the said opposing surface. Storage element.

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