JP2019175642A - Power storage element - Google Patents

Abstract

To provide a power storage element which can ensure flatness of an electrode terminal.SOLUTION: A power storage element 10 comprises: a container 100 having a first through-hole 110a; an insulation member (an upper gasket 125), having a second through-hole 125a brought into communication with the first through-hole 110a, which faces the container 100; a shaft 210 inserted through the first through-hole 110a and the second through-hole 125a; and an electrode terminal (a positive electrode terminal 200) to which the shaft 210 is connected, and which sandwiches, together with the container 100, the insulation member. A plurality of protrusions 1263 and 1271 are arranged at least on one of a first surface (a lower surface 127), of the insulation member, overlapping the container 100 and a second surface (a bottom surface 1262), of the insulation member, overlapping the electrode terminal. The plurality of protrusions 1263 and 1271 are deformed by compression.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a power storage device including an insulating member disposed between a container and a current collector.

  2. Description of the Related Art Conventionally, a power storage device including a container, an electrode terminal, a current collector, and an insulating member is widely known. For example, Patent Document 1 discloses a power storage device including a container, an electrode terminal, a current collector electrically connected to the electrode terminal, and an insulating member disposed between the container and the current collector. Has been. And these are assembled | attached by the electrode terminal being crimped in the state which penetrated the container, the insulating member, and the electrical power collector.

JP 2013-93160 A

  By the way, in a container or an electrode terminal, a minute unevenness | corrugation may exist in the surface facing an insulating member. This unevenness may hinder the flatness of the electrode terminal through the insulating member. The inclination of the electrode terminal can be a cause of a decrease in welding strength with the bus bar.

  For this reason, this invention is providing the electrical storage element which can ensure the flatness of an electrode terminal.

  In order to achieve the above object, an electricity storage device according to one embodiment of the present invention includes a container having a first through hole, a second through hole communicating with the first through hole, and an insulating member facing the container. A first portion of the insulating member that overlaps the container, and a shaft portion that is inserted into the first through hole and the second through hole, and an electrode terminal that is connected to the shaft portion and sandwiches the insulating member together with the container. A plurality of protrusions are disposed on at least one surface of the second terminal overlapping the electrode terminal, and the plurality of protrusions are compressed and deformed.

  According to this, since the plurality of protrusions are arranged on at least one of the first surface and the second surface of the insulating member and these are compressed and deformed, the plurality of protrusions after the compression deformation are unevenness of the electrode terminal. Or it will absorb the irregularities of the container. Therefore, the flatness of the electrode terminal can be ensured.

  The shaft portion is crimped in a state of being inserted through the first through hole and the second through hole, and the plurality of protrusions are compressed and deformed by the crimping.

  According to this, even when the container, the insulating member, and the electrode terminal are fastened by the crimping of the shaft portion, the plurality of protrusions absorb the unevenness of the electrode terminal and the unevenness of the container. Sex can be secured.

  Of the plurality of protrusions, at least one protrusion is disposed on one side with respect to the second through hole, and at least one other protrusion is disposed on the other side.

  According to this, at least one protrusion is disposed on one side with respect to the second through hole, and the other at least one protrusion is disposed on the other side, so that it is inserted into the second through hole. It is possible to make it difficult for the electrode terminal to be inclined with respect to the shaft portion. Therefore, the flatness of the electrode terminal can be ensured more reliably.

  The plurality of protrusions is three or more, and the protrusions are point protrusions.

  When there are two point-like protrusions, the two point-like protrusions are arranged on the same straight line, so there is a possibility that the flatness of the electrode terminal cannot be secured stably. However, if there are three or more point-like protrusions, the point-like protrusions can be arranged in a wider range, and thus the flatness of the electrode terminals can be secured stably.

  The plurality of protrusions include at least one protrusion that is not arranged on the same straight line.

  According to this, since the plurality of protrusions include protrusions that are not arranged on the same straight line, the plurality of point-like protrusions can be two-dimensionally arranged. That is, the flatness of the electrode terminal can be more stably ensured by the plurality of point-like protrusions arranged two-dimensionally.

  The plurality of protrusions are provided on the first surface.

  According to this, since the plurality of protrusions are provided on the first surface of the insulating member that overlaps the container, the plurality of protrusions absorb the unevenness on the container side that tends to hinder the flatness of the electrode terminals. It becomes. Therefore, the flatness of the electrode terminal can be reliably ensured.

  An electricity storage device according to one embodiment of the present invention includes a container having a first through hole, a second through hole communicating with the first through hole, an insulating member facing the container, the first through hole, and the second through hole. A shaft portion inserted through the through hole, an electrode terminal connected to the shaft portion and sandwiching the insulating member together with the container, a first surface overlapping the container in the insulating member, and a second surface overlapping the electrode terminal in the insulating member; A plurality of protrusions are arranged on at least one of the surfaces, and a receiving surface for receiving the plurality of protrusions in at least one of the container and the electrode terminal is formed flat.

  According to this, when the surface on which the plurality of protrusions are formed and the receiving surface are overlapped by assembly, the plurality of protrusions absorb unevenness on the receiving surface. By absorbing the unevenness of the receiving surface, the flatness of the electrode terminal can be ensured.

  According to the electricity storage device of the present invention, the flatness of the electrode terminal can be ensured.

It is a perspective view which shows the external appearance of the electrical storage element which concerns on embodiment. It is a disassembled perspective view of the electrical storage element which concerns on embodiment. It is a disassembled perspective view of the site | part except the container main body and the insulating sheet from the electrical storage element which concerns on embodiment. It is a perspective view of the upper surface side which shows schematic structure of the upper gasket which concerns on embodiment. It is a top view which shows schematic structure of the upper gasket which concerns on embodiment. It is a perspective view of the lower surface side which shows schematic structure of the upper gasket which concerns on embodiment. It is a bottom view which shows schematic structure of the upper gasket which concerns on embodiment. It is sectional drawing which shows the positional relationship of the upper gasket and other member which concern on embodiment. It is sectional drawing which shows the relationship between the lower surface of the positive electrode terminal which concerns on embodiment, and several protrusion of an upper gasket. It is sectional drawing which shows the relationship between the lower surface of the positive electrode terminal which concerns on embodiment, and several protrusion of an upper gasket. 10 is a top view illustrating a schematic configuration of an upper gasket according to Modification 1. FIG. 10 is a top view illustrating a schematic configuration of an upper gasket according to Modification 2. FIG.

  Hereinafter, a power storage device according to an embodiment of the present invention and a modification thereof will be described with reference to the drawings. It should be noted that each of the embodiments and modifications thereof described below is a comprehensive or specific example. The numerical values, shapes, materials, constituent elements, arrangement positions and connection forms of the constituent elements, manufacturing steps, order of manufacturing steps, and the like shown in the following embodiments and modifications thereof are merely examples and are intended to limit the present invention. is not. In addition, among the constituent elements in the following embodiments and modifications thereof, constituent elements that are not described in the independent claims indicating the highest concept are described as arbitrary constituent elements. Each figure is a schematic diagram, and dimensions and the like are not necessarily shown strictly.

  In the following description and drawings, the direction in which the pair of electrode terminals included in the power storage element, the direction in which the pair of converging portions of the electrode body are aligned, or the opposing direction of the short side surface of the container is defined as the X axis direction. Further, the opposing 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 stacking direction of the electrode plates of the electrode body is defined as the Y-axis direction. Further, the direction in which the container body and the lid of the storage element are arranged, the longitudinal direction of the short side surface of the container, the axial direction of the shaft portion of the electrode terminal, or the vertical direction is defined as the Z-axis direction. These X-axis direction, Y-axis direction, and Z-axis direction are directions that intersect (orthogonal in this embodiment). Although the case where the Z-axis direction does not become the vertical direction may be considered depending on the usage mode, the Z-axis direction will be described below as the vertical direction for convenience of explanation. 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. Configuration of storage element]
First, a general description of the power storage element 10 according to the present embodiment will be described with reference to FIGS. FIG. 1 is a perspective view showing an external appearance of a power storage element 10 according to the embodiment. FIG. 2 is an exploded perspective view of the energy storage device 10 according to the embodiment. FIG. 3 is an exploded perspective view of a portion excluding the container main body 101 and the insulating sheet 500 from the power storage element 10 according to the embodiment.

  The storage element 10 is a secondary battery that can charge electricity and discharge electricity, and specifically, is a non-aqueous electrolyte secondary battery such as a lithium ion secondary battery. The power storage element 10 is, for example, a power source for an automobile (or a moving body) such as an electric vehicle (EV), a hybrid electric vehicle (HEV), or a plug-in hybrid electric vehicle (PHEV), a power source for electronic equipment, or a power storage power source. Applicable to etc. In addition, the electrical storage element 10 is not limited to a nonaqueous electrolyte secondary battery, A secondary battery other than a nonaqueous electrolyte secondary battery may be sufficient, and a capacitor may be sufficient as it. The electricity storage element 10 may be a primary battery that can use the stored electricity without being charged by the user. Further, the power storage element 10 may be an all-solid battery.

  As shown in these drawings, the storage element 10 includes a container 100, an electrode body 400, an insulating sheet 500, and a pair of side spacers 700. In addition, although electrolyte solution (nonaqueous electrolyte) is enclosed inside the container 100, illustration is abbreviate | omitted. There are no particular restrictions on the type of the electrolytic solution as long as it does not impair the performance of the electricity storage element 10, and various types can be selected.

  In the present embodiment, a lid structure 180 configured by arranging various elements on the lid 110 of the container 100 is disposed above the electrode body 400. In the container 100, one end portion of the electrode body 400 faces the lid structure 180.

  The container 100 includes a container body 101 having a rectangular cylindrical shape and a bottom, and a lid 110 that closes an opening of the container body 101. In the container 100, an electrode body 400, an insulating sheet 500, and a pair of side spacers 700 are accommodated. The container 100 has a structure in which the interior of the container 100 is sealed by welding the lid body 110 and the container body 101 after the electrode body 400 and the like are accommodated therein. The container 100 (the lid body 110 and the container body 101) is formed of a weldable metal such as stainless steel, aluminum, or an aluminum alloy, for example. The lid body 110 and the container body 101 are preferably formed of the same material, but may be formed of different materials. In addition, the lid 110 is provided with a liquid injection port 124 for injecting an electrolytic solution into the container 100. The liquid injection port 124 is blocked by a liquid injection plug 123. In addition, the lid 110 may be provided with a gas discharge valve or the like that discharges the gas inside the container 100 when the internal pressure of the container 100 rises.

  The lid structure 180 includes a lid body 110 of the container 100, a positive electrode terminal 200, a negative electrode terminal 300, upper gaskets 125 and 135, lower gaskets 120 and 130, a positive electrode current collector 140, and a negative electrode current collector 150.

  The lid 110 is a plate-like member, and as shown in FIG. 3, a liquid inlet 124, first through holes 110 a and 110 b, and two bulging portions 160 are formed. The liquid injection port 124 is a through-hole for injecting an electrolytic solution when the power storage element 10 is manufactured. In the present embodiment, each of the two bulging portions 160 is provided in the lid body 110 by forming a part of the lid body 110 in a bulging shape. For example, the upper gaskets 125 and 135 Used for positioning. Further, a concave portion 161 (see FIG. 8), which is a concave portion, is formed on the back side of the bulging portion 160 (the side facing the electrode body 400), and the lower gasket 120, 130 engagement protrusions 120b and 130b are engaged. Thereby, the lower gaskets 120 and 130 are also positioned and fixed to the lid 110 in this state.

  The upper gaskets 125 and 135 and the lower gaskets 120 and 130 are insulators, and are formed of an insulating resin such as polypropylene (PP), polyethylene (PE), or polyphenylene sulfide resin (PPS). Yes.

  The upper gasket 125 is a member that electrically insulates the positive electrode terminal 200 and the lid 110. The upper gasket 125 is formed with a second through hole 125a through which the shaft portion 210 of the positive electrode terminal 200 passes. The lower gasket 120 is a member that electrically insulates the positive electrode current collector 140 from the lid 110. The lower gasket 120 has a through hole 120a through which the shaft portion 210 of the positive electrode terminal 200 passes.

  The upper gasket 135 is a member that electrically insulates the negative electrode terminal 300 from the lid 110. The upper gasket 135 is formed with a second through hole 135a through which a shaft portion (not shown) of the negative electrode terminal 300 passes. The lower gasket 130 is a member that electrically insulates the negative electrode current collector 150 from the lid 110. The lower gasket 130 is formed with a through hole 130a through which the shaft portion of the negative electrode terminal 300 passes.

  The upper gaskets 125 and 135 may be referred to as upper packing, for example, and the lower gaskets 120 and 130 may be referred to as lower packing, for example. That is, in this embodiment, the upper gaskets 125 and 135 also have a function of sealing between the electrode terminal (200 or 300) and the container 100. The lower gaskets 120 and 130 may also have a function of sealing between the electrode terminal (200 or 300) and the container 100.

  The lower gaskets 120 and 130 are provided with engaging portions 121 and 131 that engage with the side spacer 700. Specifically, the engaging portions 121 and 131 protrude in the X-axis direction outward from one end portion outside the lower gaskets 120 and 130. Reinforcing ribs 122 and 132 are erected on both side portions of the engaging portions 121 and 131 in the Y-axis direction. The reinforcing ribs 122 and 132 are inclined so that the height decreases toward the tips of the engaging portions 121 and 131. The strength of the engaging portions 121 and 131 is increased by the reinforcing ribs 122 and 132.

  When the engaging portions 121 and 131 are engaged with the side spacer 700, the positions of the lower gaskets 120 and 130 with respect to the side spacer 700 are determined. As a result, the position of the lid structure 180 with respect to the side spacer 700 is determined.

  As shown in FIGS. 1 to 3, the positive electrode terminal 200 is an electrode terminal electrically connected to the positive electrode of the electrode body 400 via the positive electrode current collector 140. The negative electrode terminal 300 is an electrode terminal electrically connected to the negative electrode of the electrode body 400 via the negative electrode current collector 150. That is, the positive electrode terminal 200 and the negative electrode terminal 300 are used to lead the electricity stored in the electrode body 400 to the external space of the power storage element 10 and to store the electricity in the electrode body 400. It is a metal electrode terminal for introducing electricity into the wire. The positive terminal 200 is made of aluminum or aluminum alloy, and the negative terminal 300 is made of copper or copper alloy.

  Further, the positive electrode terminal 200 is provided with a shaft portion 210 (see FIG. 8) for fastening the container 100 and the positive electrode current collector 140. The negative electrode terminal 300 is provided with a shaft portion (not shown) that fastens the container 100 and the negative electrode current collector 150.

  The shaft portion 210 of the positive electrode terminal 200 is a member (rivet) extending downward from the positive electrode terminal 200 and is inserted into the through hole 140 a of the positive electrode current collector 140 and crimped. Specifically, the shaft portion 210 of the positive electrode terminal 200 includes the second through hole 125 a of the upper gasket 125, the first through hole 110 a of the lid 110, the through hole 120 a of the lower gasket 120, and the positive electrode current collector 140. It is inserted into the through hole 140a and crimped. Thereby, the positive electrode terminal 200 and the positive electrode current collector 140 are electrically connected, and the positive electrode current collector 140 is fixed to the lid 110 together with the positive electrode terminal 200, the upper gasket 125, and the lower gasket 120.

  A shaft portion of the negative electrode terminal 300 is a member (rivet) extending downward from the negative electrode terminal 300, and is inserted into the through hole 150 a of the negative electrode current collector 150 and crimped. Specifically, the shaft portion is inserted into the second through hole 135 a of the upper gasket 135, the first through hole 110 b of the lid 110, the through hole 130 a of the lower gasket 130, and the through hole 150 a of the negative electrode current collector 150. Be caulked. Thereby, the negative electrode terminal 300 and the negative electrode current collector 150 are electrically connected, and the negative electrode current collector 150 is fixed to the lid 110 together with the negative electrode terminal 300, the upper gasket 135, and the lower gasket 130.

  The shaft portion 210 may be formed as an integral part of the positive electrode terminal 200, and the shaft portion manufactured as a separate component from the positive electrode terminal 200 is connected to the positive electrode terminal 200 by a technique such as caulking or welding. It does not matter. The same applies to the relationship between the negative electrode terminal 300 and its shaft portion.

  The positive electrode current collector 140 is a member that is disposed between the electrode body 400 and the lid body 110 and electrically connects the electrode body 400 and the positive electrode terminal 200. The positive electrode current collector 140 is made of aluminum or an aluminum alloy. The positive electrode current collector 140 is formed with a through hole 140 a through which the shaft portion 210 of the positive electrode terminal 200 passes.

  The negative electrode current collector 150 is a member that is disposed between the electrode body 400 and the lid body 110 and electrically connects the electrode body 400 and the negative electrode terminal 300. The negative electrode current collector 150 is made of copper or a copper alloy. The negative electrode current collector 150 has a through hole 150 a through which the shaft portion of the negative electrode terminal 300 passes.

  As shown in FIG. 3, the electrode body 400 includes a positive electrode plate, a negative electrode plate, and a separator, and is an electric storage element (power generation element) that can store electricity, and is disposed inside the container 100. Specifically, the electrode body 400 is a stacked electrode body in which a positive electrode plate and a negative electrode plate are alternately arranged with a separator interposed therebetween. 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 that is a long strip-shaped current collector foil made of aluminum, an 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 that is a long strip-shaped current collector foil made of copper, a copper alloy, or the like. Note that as the current collector foil, a known material such as nickel, iron, stainless steel, titanium, baked carbon, a conductive polymer, conductive glass, or an Al—Cd alloy can be used as appropriate. Moreover, as a positive electrode active material and a negative electrode active material used for a positive electrode active material layer and a negative electrode active material layer, if it is an active material which can occlude-release lithium ion, a well-known material can be used suitably. Moreover, the separator can use the microporous sheet | seat which consists of resin, for example, and a nonwoven fabric.

  The electrode body 400 includes an electrode body main body 401 that is a part that generates and stores power, and a positive electrode focusing part 415 and a negative electrode focusing part 425 that are parts that exchange power between the electrode body main body 401 and the outside.

  On the upper part of the electrode body 401, adhesive tapes 370 are attached at two locations. In addition, adhesive tapes 370 are attached at three locations below the electrode body main body 401. These adhesive tapes 370 prevent misalignment between the positive electrode plate, the negative electrode plate, and the separator.

  The positive electrode focusing portion 415 protrudes from the minus side in the X-axis direction on the top surface of the electrode body main body 401. The positive electrode converging part 415 is formed by bundling portions where the positive electrode active material is not applied and the positive electrode base material layer is exposed in each positive electrode plate. The negative electrode focusing part 425 protrudes from the X axis direction plus side on the top surface of the electrode body main body 401. The negative electrode converging portion 425 is formed by bundling portions where the negative electrode active material is not applied and the negative electrode base material layer is exposed in each negative electrode plate.

  The positive electrode focusing portion 415 is bonded to the positive electrode current collector 140, and the negative electrode focusing portion 425 is bonded to the negative electrode current collector 150. That is, the positive electrode focusing unit 415 is electrically connected to the positive electrode terminal 200 via the positive electrode current collector 140, and the negative electrode focusing unit 425 is electrically connected to the negative electrode terminal 300 via the negative electrode current collector 150. . Thereby, the electrode body 400 can exchange electric power with an external apparatus etc. via the positive electrode terminal 200 and the negative electrode terminal 300. FIG.

  In addition, it is possible to use a well-known joining method for joining a focusing part and a collector. Examples of the joining method include welding such as ultrasonic welding and laser welding, and fastening such as caulking or screwing.

  Next, the upper gasket 125 according to the present embodiment will be described. Here, the upper gasket 125 on the positive electrode side will be described as an example, but the same applies to the upper gasket 135 on the negative electrode side, and therefore the description of the upper gasket 135 on the negative electrode side will be omitted.

  FIG. 4 is a top perspective view showing a schematic configuration of the upper gasket 125 according to the present embodiment. FIG. 5 is a top view showing a schematic configuration of the upper gasket 125 according to the present embodiment. FIG. 6 is a perspective view of the lower surface side showing a schematic configuration of the upper gasket 125 according to the present embodiment. FIG. 7 is a bottom view showing a schematic configuration of the upper gasket 125 according to the present embodiment.

  As shown in FIGS. 4 and 5, a recess 1261 is provided around the second through hole 125 a on the upper surface 126 of the upper gasket 125. When the shaft part 210 of the positive electrode terminal 200 is inserted into the second through hole 125a, a part of the positive electrode terminal 200 is accommodated in the recess 1261. A plurality of protrusions 1263 are discretely arranged on the bottom surface 1262 of the recess 1261. Portions other than the protrusions 1263 on the bottom surface 1262 are formed in a planar shape.

  The protrusion 1263 is a point-like protrusion. Specifically, the protrusion 1263 is formed in a cylindrical shape. The protrusion 1263 may have other shapes. Examples of other shapes include a hemispherical shape, a cone shape, and a polygonal column shape.

  In this embodiment, three protrusions 1263 are provided. The three protrusions 1263 are arranged around the second through hole 125a. The three protrusions 1263 are arranged at positions that form vertices of a virtual triangle in which the entire second through hole 125a is accommodated. That is, the three protrusions 1263 are not arranged on the same straight line. The plurality of protrusions 1263 may include at least one protrusion 1263 that is not arranged on the same straight line.

  Of the three protrusions 1263, one protrusion 1263 is arranged on one side (in this embodiment, the X axis direction plus side) with respect to the second through hole 125a, and the other protrusions 1263 are on the other side ( In this embodiment, it is arranged on the X axis direction minus side). In this embodiment, “one side” and “the other side” are distributed in the X-axis direction, but may be distributed in the Y-axis direction or in a direction inclined with respect to the X-axis direction. .

  As shown in FIGS. 6 and 7, the lower surface 127 of the upper gasket 125 is provided with a cylindrical portion 128 that protrudes downward so as to surround the entire circumference of the second through-hole 125 a. A fitting recess 129 into which the bulging portion 160 of the lid 110 is fitted is formed on the lower surface 127 of the upper gasket 125. The fitting recess 129 is recessed in a shape corresponding to the bulging portion 160. A plurality of protrusions 1271 are discretely arranged on the lower surface 127 of the upper gasket 125. Portions other than the cylindrical portion 128, the fitting recess 129, and the protrusion 1271 on the lower surface 127 are formed in a planar shape.

  The protrusion 1271 is a point-like protrusion. Specifically, the protrusion 1271 is formed in a cylindrical shape. The protrusion 1271 may have other shapes. Examples of other shapes include a hemispherical shape, a cone shape, and a polygonal column shape.

  In this embodiment, three protrusions 1271 are provided. The three protrusions 1271 are arranged around the cylindrical portion 128. The three protrusions 1271 are arranged at positions that form vertices of a virtual triangle in which the entire second through hole 125a is accommodated. That is, the three protrusions 1271 are not arranged on the same straight line. The plurality of protrusions 1271 may include at least one protrusion 1271 that is not arranged on the same straight line.

  Of the three protrusions 1271, one protrusion 1271 is arranged on one side (in this embodiment, the X axis direction plus side) with respect to the second through hole 125a, and the other protrusion 1263 is on the other side ( In this embodiment, it is arranged on the X axis direction minus side). In this embodiment, “one side” and “the other side” are distributed in the X-axis direction, but may be distributed in the Y-axis direction or in a direction inclined with respect to the X-axis direction. .

  Next, the positional relationship between the upper gasket 125 and other members in the container 100 will be described. FIG. 8 is a cross-sectional view showing the positional relationship between the upper gasket 125 and other members according to the present embodiment.

  As shown in FIG. 8, the upper gasket 125 is attached on the lid 110 with the cylindrical portion 128 inserted through the first through hole 110 a of the lid 110 and the through hole 140 a of the positive electrode current collector 140. . The shaft portion 210 of the positive electrode terminal 200 is inserted into the second through hole 125 a of the upper gasket 125 and the through hole 140 a of the positive electrode current collector 140. The shaft portion 210 of the positive electrode terminal 200 is crimped, whereby the positive electrode terminal 200 and the positive electrode current collector 140 sandwich the upper gasket 125, the lid 110, and the lower gasket 120 via the shaft portion 210. . A lower surface 127 of the upper gasket 125 is a first surface overlapping the upper surface 115 of the lid 110. The plurality of protrusions 1271 on the lower surface 127 are received by the upper surface 115 of the lid 110 and are compressed and deformed. That is, the upper surface 115 of the lid 110 is a receiving surface that receives the plurality of protrusions 1271. A bottom surface 1262 of the recess 1261 in the upper gasket 125 is a second surface overlapping the lower surface 205 of the positive electrode terminal 200. The plurality of protrusions 1263 on the bottom surface 1262 are received by the lower surface 205 of the positive electrode terminal 200 and are compressed and deformed. That is, the lower surface 205 of the positive electrode terminal 200 is a receiving surface that receives the plurality of protrusions 1263.

  The receiving surface (the upper surface 115 of the lid 110 and the lower surface 205 of the positive electrode terminal 200) is formed flat. However, it is difficult to form the receiving surface completely flat for manufacturing, and the receiving surface is slightly uneven.

  9 and 10 are cross-sectional views showing the relationship between the lower surface 205 of the positive electrode terminal 200 and the plurality of protrusions 1263 of the upper gasket 125 according to the present embodiment. 9 and 10 are cross-sectional views of the section IX-IX in FIG. 9 shows a state immediately before the shaft part 210 of the positive electrode terminal 200 is crimped, and FIG. 10 shows a state after the shaft part 210 of the positive electrode terminal 200 is crimped. In FIGS. 9 and 10, the unevenness of the lower surface 205 of the positive electrode terminal 200 is highlighted.

  As shown in FIG. 9, the lower surface 205 of the positive electrode terminal 200 is slightly recessed. Before caulking, two of the three protrusions 1263 are in contact with the lower surface 205 of the positive electrode terminal 200, and the remaining protrusions 1263 are not in contact with the lower surface 205 of the positive electrode terminal 200. Thereafter, when the shaft portion 210 of the positive electrode terminal 200 is crimped, the positive electrode terminal 200 approaches the upper gasket 125 and compresses and deforms the three protrusions 1263. Originally, one protrusion 1263 that was not in contact with the lower surface 205 of the positive electrode terminal 200 has a smaller deformation amount than the other two protrusions 1263. As described above, the deformation amount of each protrusion 1263 varies depending on the unevenness of the lower surface 205 of the positive electrode terminal 200. Thereby, the unevenness | corrugation of the lower surface 205 of the positive electrode terminal 200 is absorbed, and the flatness of the positive electrode terminal 200 is ensured. The same applies to the upper surface 115 of the lid 110 and the plurality of protrusions 1271 below the upper gasket 125.

  Here, the flatness of the positive electrode terminal 200 refers to flatness based on at least one of the bottom surface of the container body 101 and the main surface (the stripe 115 or the lower surface 205) of the lid 110, for example.

[2. Method for manufacturing power storage element]
Next, the manufacturing method of the electrical storage element 10 is demonstrated. In the following description, a case where the worker assembles the electricity storage element 10 is illustrated, but the assembly apparatus can also assemble the electricity storage element 10.

  First, the operator joins the positive electrode current collector 140 to the positive electrode focusing part 415 of the electrode body 400 and joins the negative electrode current collector 150 to the negative electrode focusing part 425 of the electrode body 400. Thereafter, the operator assembles the positive electrode terminal 200, the negative electrode terminal 300, the upper gaskets 125 and 135, the lower gaskets 120 and 130, the positive electrode current collector 140, and the negative electrode current collector 150 to the lid body 110 of the container 100. Thereby, the electrode body 400 and the lid structure 180 are integrated.

  At the time of this assembly, the shaft portion 210 of the positive electrode terminal 200 is caulked. Since the plurality of protrusions 1263 and 1271 of the upper gasket 125 are compressed and deformed by this caulking, there are a plurality of irregularities on the lower surface 205 (receiving surface) of the positive electrode terminal 200 and the upper surface 115 (receiving surface) of the lid 110. It is absorbed by the protrusions 1263 and 1271. Thereby, the flatness of the positive electrode terminal 200 with respect to the cover body 110 is ensured. The same applies to the upper gasket 135 on the negative electrode side. In addition, after crimping, the cylinder part 128 of the upper gasket 125 is also compressed and deformed. The cylindrical portion 128 expands in the radial direction by this compression deformation, so that the cylindrical portion 128 is in close contact with the inner peripheral surface forming the first through hole 110a of the lid 110 and the outer peripheral surface of the shaft portion 210 of the positive electrode terminal 200, Ensure airtightness.

  Next, the operator attaches a pair of side spacers 700 to the electrode body 400, and then attaches an adhesive tape 380 to each side spacer 700 and the electrode body 400, so that a pair of side spacers is attached to the electrode body 400. The spacer 700 is fixed. Next, the operator winds and fixes the insulating sheet 500 around the electrode body 400. Thereby, the lid structure 180, the electrode body 400, the pair of side spacers 700, and the insulating sheet 500 are integrated.

  Next, the operator inserts the integrated lid structure 180, the electrode body 400, the pair of side spacers 700, and the insulating sheet 500 into the container body 101. After insertion, the operator assembles the container 100 by welding the lid 110 to the container main body 101. Thereafter, the operator injects the electrolytic solution from the liquid injection port 124 and fills the container 100 with the electrolytic solution. After the injection of the electrolytic solution, the operator closes the liquid injection port 124 with the liquid injection plug 123 as shown in FIG.

[3. Effect]
As described above, power storage element 10 according to the present embodiment has container 100 having first through hole 110a and second through hole 125a communicating with first through hole 110a, and faces container 100. The upper gasket 125 (insulating member), the shaft portion 210 inserted through the first through hole 110a and the second through hole 125a, and the positive electrode terminal 200 (electrode terminal) that connects the shaft portion 210 and sandwiches the upper gasket 125 together with the container 100 And a plurality of protrusions on at least one surface of a lower surface 127 (first surface) that overlaps the container 100 of the upper gasket 125 and a bottom surface 1262 (second surface) that overlaps the positive electrode terminal 200 of the upper gasket 125. 1263 and 1271 are arranged, and the plurality of protrusions 1263 and 1271 are compressed and deformed.

  According to this, since the plurality of protrusions 1263 and 1271 are disposed on at least one of the first surface and the second surface of the upper gasket 125 and these are compressed and deformed, the plurality of protrusions 1263 after the compression deformation. 1271 absorbs the unevenness of the positive electrode terminal 200 and the unevenness of the container 100. Therefore, the flatness of the positive electrode terminal 200 can be ensured. Thereby, the bus bar can be reliably welded to the positive electrode terminal 200, and the welding strength between the bus bar and the positive electrode terminal 200 can be increased.

  In addition, the electricity storage device 10 according to the present embodiment includes a container 100 having a first through hole 110a, a second through hole 125a communicating with the first through hole 110a, and an upper gasket 125 facing the container 100. , The shaft portion 210 inserted through the first through hole 110a and the second through hole 125a, and the positive electrode terminal 200 to which the shaft portion 210 is connected and sandwich the upper gasket 125 together with the container 100. A plurality of protrusions 1263 and 1271 are arranged on at least one surface of the lower surface 127 that overlaps and the bottom surface 1262 that overlaps the positive electrode terminal 200 of the upper gasket 125, and a plurality of protrusions at least one of the container 100 and the positive electrode terminal 200. The upper surface 115 and the lower surface 205 (receiving surface) that receive the protrusions 1263 and 1271 are formed flat. There.

  According to this, when the surface on which the plurality of protrusions 1263 and 1271 are formed (the lower surface 127 and the bottom surface 1262) and the receiving surface are overlapped by assembly, the plurality of protrusions 1263 and 1271 absorb the unevenness on the receiving surface. Will do. By absorbing the unevenness of the receiving surface, the flatness of the positive electrode terminal 200 can be ensured. Thereby, the bus bar can be reliably welded to the positive electrode terminal 200, and the welding strength between the bus bar and the positive electrode terminal 200 can be increased.

  The shaft portion 210 is crimped in a state of being inserted into the first through hole 110a and the second through hole 125a, and the plurality of protrusions 1263 and 1271 are compressed and deformed by crimping.

  According to this, even when the container 100, the upper gasket 125, and the positive electrode terminal 200 are fastened by the crimping of the shaft portion 210, the plurality of protrusions 1263 and 1271 are unevenness of the positive electrode terminal 200 or unevenness of the container 100. Therefore, the flatness of the positive electrode terminal 200 can be ensured.

  In addition, the positive electrode terminal 200 may be inclined due to an external force caused by caulking, but this inclination can also be absorbed by the plurality of protrusions 1263 and 1271. In particular, when the shaft portion is displaced from the center of the positive electrode terminal, an inclination due to caulking is likely to occur in the positive electrode terminal. In this case, it is effective that the upper gasket 125 is provided with a plurality of protrusions 1263 and 1271 as in the present embodiment.

  Of the plurality of protrusions 1263 and 1271, at least one protrusion 1263 and 1271 is arranged on one side with respect to the second through hole 125a, and the other at least one protrusion 1263 and 1271 is on the other side. Has been placed.

  According to this, at least one protrusion 1263, 1271 is disposed on one side with respect to the second through hole 125a, and the other at least one protrusion 1263, 1271 is disposed on the other side. It is possible to make it difficult for the positive electrode terminal 200 to have an inclination around the shaft portion 210 inserted into the second through hole 125a. Therefore, the flatness of the positive electrode terminal 200 can be ensured more reliably.

  The plurality of protrusions 1263 and 1271 are three or more, and the protrusions 1263 and 1271 are dot-like protrusions.

  When there are two point-like protrusions, the two point-like protrusions are arranged on the same straight line, and thus there is a possibility that the flatness of the positive electrode terminal 200 cannot be secured stably. However, if there are three or more projections 1263 and 1271 that are dot-like projections, the projections 1263 and 1271 can be arranged in a wider range, and thus the flatness of the positive electrode terminal 200 can be stably secured.

  Since the plurality of protrusions 1263 and 1271 are point-like protrusions, point contact is made with respect to the positive electrode terminal 200 and the lid body 110. For this reason, the plurality of protrusions 1263 and 1271 can be compressed and deformed with a low load.

  Further, since the dot-like projections are solid, they are less likely to be damaged during compression deformation than, for example, an annular projection having the same outer shape.

  The plurality of protrusions 1263 and 1271 include at least one protrusion 1263 and 1271 that are not arranged on the same straight line.

  According to this, since the plurality of protrusions 1263 and 1271 include the protrusions 1263 and 1271 that are not arranged on the same straight line, the plurality of protrusions 1263 and 1271 can be two-dimensionally arranged. That is, the flatness of the positive electrode terminal 200 can be more stably ensured by the plurality of protrusions 1263 and 1271 arranged two-dimensionally.

  The plurality of protrusions 1263 and 1271 are provided on the lower surface 127 (first surface) of the upper gasket 125.

  According to this, since the plurality of protrusions 1271 are provided on the lower surface 127 of the upper gasket 125, the plurality of protrusions 1271 absorb the unevenness on the container 100 side that tends to hinder the flatness of the positive electrode terminal 200. It will be. Therefore, the flatness of the positive electrode terminal 200 can be reliably ensured.

[4. Modified example]
The power storage element 10 according to the above embodiment has been described above, but the power storage element 10 may include an upper gasket different from the above-described aspect. Thus, hereinafter, a modification of the upper gasket provided in the electricity storage element 10 will be described focusing on the difference from the above embodiment. In the following description, the same parts as those in the above embodiment may be denoted by the same reference numerals and the description thereof may be omitted.

(Modification 1)
In the above embodiment, the upper gasket 125 provided with three protrusions 1263 and 1271 is illustrated. However, four or more of the protrusions 1263 and 1271 may be provided. FIG. 11 is a top view illustrating a schematic configuration of the upper gasket 125B according to the first modification. Specifically, FIG. 11 is a diagram corresponding to FIG. As shown in FIG. 11, four or more protrusions 1263 are arranged in the bottom face 1262 of the upper gasket 125B. The four or more protrusions 1263 are equally arranged. Specifically, the four or more protrusions 1263 are arranged in a matrix. If the number of the plurality of protrusions 1263 and 1271 is large, the unevenness of the positive electrode terminal 200 or the unevenness of the lid 110 can be reliably absorbed. That is, the flatness of the positive electrode terminal 200 can be more reliably maintained. In particular, if the plurality of protrusions 1263 and 1271 are evenly arranged, the flatness can be more reliably maintained.

(Modification 2)
FIG. 12 is a top view illustrating a schematic configuration of an upper gasket 125C according to the second modification. In the said embodiment or the modification 1, the case where the some protrusion 1263,1271 was arrange | positioned with predetermined regularity was illustrated. However, a plurality of protrusions 1263 may be randomly arranged as in the upper gasket 125C shown in FIG.

[5. Other Embodiments]
As described above, the power storage device according to the present invention has been described based on the embodiment and the modifications thereof. However, the present invention is not limited to the above-described embodiments and modifications. Without departing from the gist of the present invention, various modifications conceived by those skilled in the art may be applied to the above-described embodiment or modification, or a form constructed by combining a plurality of the constituent elements described above. It is included in the range.

  For example, in the above embodiment, the stacked electrode body 400 in which the positive electrode plate and the negative electrode plate are alternately arranged with the separator interposed therebetween is exemplified. However, the electrode body may be a laminated electrode body in which a positive electrode plate and a negative electrode plate are folded in a bellows shape with a separator interposed therebetween. The electrode body may be a wound electrode body in which a positive electrode plate and a negative electrode plate are wound with a separator interposed therebetween.

  Moreover, in the said embodiment, the case where the some protrusion 1263,1271 was compression-deformed by crimping the axial part 210 of the positive electrode terminal 200 was illustrated. However, the plurality of protrusions 1263 and 1271 can be compressed and deformed by a fastening method other than caulking. Specifically, a method of compressing and deforming the plurality of protrusions 1263 and 1271 by screw fastening to the shaft portion of the positive electrode terminal can be used. Even in this case, the flatness of the positive electrode terminal 200 can be ensured.

  Moreover, in the said embodiment, the case where several protrusion 1263,1271 was provided in each of the 1st surface (lower surface 127) and the 2nd surface (bottom surface 1262) in the upper gasket 125 was illustrated. However, a plurality of protrusions may be provided on at least one of the first surface and the second surface of the upper gasket 125.

  Moreover, in the said embodiment, the case where the axial part 210 of the positive electrode terminal 200 was crimped to the positive electrode collector 140 inside the container 100 was illustrated. However, the upper gasket 125 according to the present embodiment can be applied even to a so-called outer caulking structure in which the shaft portion of the positive electrode current collector is caulked to the positive electrode terminal outside the container.

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

DESCRIPTION OF SYMBOLS 10 Power storage element 100 Container 101 Container main body 110 Cover body 110a, 110b 1st through-hole 115 Upper surface (receiving surface)
120, 130 Lower gasket 120a, 130a, 140a, 150a Through hole 120b, 130b Engaging protrusion 121, 131 Engaging portion 122, 132 Reinforcing rib 123 Injecting plug 124 Injecting port 125, 125B, 125C, 135 Upper gasket ( Insulating material)
125a, 135a Second through-hole 126 Upper surface 127 Lower surface (first surface)
128 Cylinder portion 129 Fitting recess 140 Positive electrode current collector 150 Negative electrode current collector 160 Swelling portion 161 Recess 180 Lid structure 200 Positive electrode terminal (electrode terminal)
205 Bottom surface (receiving surface)
210 Shaft portion 300 Negative electrode terminal 370, 380 Adhesive tape 400 Electrode body 401 Electrode body main body 415 Positive electrode focusing portion 425 Negative electrode focusing portion 500 Insulating sheet 700 Side spacer 1261 Recess 1262 Bottom surface (second surface)
1263, 1271 Projection

Claims (7)

A container having a first through hole;
An insulating member having a second through hole communicating with the first through hole and facing the container;
A shaft portion inserted through the first through hole and the second through hole;
The shaft portion is connected, and the electrode terminal sandwiching the insulating member together with the container,
A plurality of protrusions are disposed on at least one surface of the first surface of the insulating member that overlaps the container and the second surface of the insulating member that overlaps the electrode terminal,
The plurality of protrusions are compressed and deformed. The shaft portion is crimped in a state inserted through the first through hole and the second through hole,
The power storage element according to claim 1, wherein the plurality of protrusions are compressed and deformed by caulking. The at least one projection among the plurality of projections is arranged on one side with respect to the second through hole, and the other at least one projection is arranged on the other side. The electricity storage device described. The power storage device according to claim 3, wherein the plurality of protrusions are three or more, and the protrusions are dot-like protrusions. The power storage element according to claim 4, wherein the plurality of protrusions include at least one protrusion that is not arranged on the same straight line. The power storage element according to any one of claims 1 to 5, wherein the plurality of protrusions are provided on the first surface. A container having a first through hole;
An insulating member having a second through hole communicating with the first through hole and facing the container;
A shaft portion inserted through the first through hole and the second through hole;
The shaft portion is connected, and the electrode terminal sandwiching the insulating member together with the container,
A plurality of protrusions are disposed on at least one surface of the first surface of the insulating member that overlaps the container and the second surface of the insulating member that overlaps the electrode terminal,
A receiving surface that receives the plurality of protrusions in at least one of the container and the electrode terminal is formed in a flat shape.

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