JP2018056081A - Power storage element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inhibit damage of an electrode body and improve impact resistance.SOLUTION: A power storage element 10 includes: an electrode body 400; a container 100 which houses the electrode body 400; a spacer (a side spacer 700) disposed between the container 100 and the electrode body 400; and a sheet member (an insulation sheet 350) which is fixed to the spacer and the electrode body 400 while covering an area from one end part to the other end part of the electrode body 400.SELECTED DRAWING: Figure 11

Description

  The present invention relates to a power storage element.

  2. Description of the Related Art Conventionally, as a power storage element, a power storage element is known in which an insulating spacer is interposed between a container and an electrode body in order to prevent contact between the container and the electrode body (for example, see Patent Document 1).

JP 2011-216239 A

  However, if vibration, impact, or the like acts on the power storage element, the electrode body may collide with the container in a region where there is no spacer, and the electrode body may be damaged.

  For this reason, the subject of this invention is suppressing the damage of an electrode body and improving impact resistance.

  In order to achieve the above object, an energy storage device according to one embodiment of the present invention includes an electrode body, a container that houses the electrode body, a spacer that is interposed between the container and the electrode body, and one end of the electrode body. A sheet member fixed to the spacer and the electrode body in a state of covering up to the other end.

  According to this configuration, since the sheet member is fixed to the spacer and the electrode body, the spacer receives an impact load acting on the electrode body via the sheet member. Therefore, damage to the electrode body can be suppressed and impact resistance can be improved.

  Moreover, since the sheet member covers from one end to the other end of the electrode body, it is possible to protect one side surface of the electrode body with the sheet member.

  Further, the sheet member may be fixed by being welded to the spacer and the electrode body.

  According to this configuration, since the sheet member is welded to the spacer and the electrode body, the sheet member can be fixed to the spacer and the electrode body without using a separate member for fixing them.

  The spacer may be provided on each of the one end and the other end of the electrode body, and the sheet member may be fixed to each of the spacer on the one end side and the spacer on the other end side of the electrode body. .

  According to this configuration, since the sheet member is fixed to each of the spacer on the one end side and the spacer on the other end side of the electrode body, the impact load acting on the electrode body is applied to the one end side via the sheet member. And the spacer on the other end side. Therefore, damage to the electrode body can be further suppressed.

  The sheet member may be wound around the electrode body and the spacer.

  According to this configuration, since the sheet member is wound around the spacer and the electrode body, the sheet member can restrain the spacer and the electrode body. Therefore, the integrity of the spacer and the sheet member can be enhanced, and the impact resistance can be further enhanced.

  Further, the sheet member may be wound in a plurality of layers with respect to the spacer and the electrode body, and may be fixed to the spacer and the electrode body in each layer.

  According to this configuration, since the sheet member is wound in a plurality of layers with respect to the spacer and the electrode body, the integrity between the spacer and the sheet member can be further improved. In addition, since each layer of the sheet member is fixed to the spacer and the electrode body, it is possible to prevent the layers of the sheet member from varying.

  ADVANTAGE OF THE INVENTION According to this invention, damage to an electrode body can be suppressed and impact resistance can be improved.

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 lid structure which concerns on embodiment. It is a perspective view which shows the structure of the electrode body which concerns on embodiment. It is the front view which looked at the side spacer which concerns on embodiment from the outside. It is the rear view which looked at the side spacer which concerns on embodiment from the inner side. It is a side view of the side spacer which concerns on embodiment. It is a top view of the side spacer which concerns on embodiment. It is a front view which shows typically the state which wound the insulating sheet which concerns on embodiment to the electrode body and the side spacer. It is sectional drawing which looked at the cut surface containing the XX cut line in FIG. It is a front view which shows the positional relationship of an electrode body, a side spacer, and an insulating sheet within the container main body which concerns on embodiment. It is sectional drawing which shows typically the state which wound the insulating sheet which concerns on the modification 1 around the electrode body and the side spacer. It is sectional drawing which shows typically the state which wound the insulating sheet which concerns on the modification 2 around the electrode body and the side spacer. It is sectional drawing which shows typically the state which wound the insulating sheet which concerns on the modification 3 to the electrode body and the side spacer.

  Hereinafter, a power storage device according to an embodiment of the present invention will be described with reference to the drawings. Each figure is a schematic diagram and is not necessarily illustrated exactly.

  The embodiment described below shows a specific example of the present invention. The shapes, materials, constituent elements, arrangement positions and connection forms of constituent elements, order of manufacturing steps, and the like shown in the following embodiments are merely examples, and are not intended to limit the present invention. In addition, among the constituent elements in the following embodiments, constituent elements that are not described in the independent claims indicating the highest concept are described as optional constituent elements.

  First, a general description of the power storage element 10 according to the 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 the lid structure 180 according to the embodiment.

  For convenience of explanation, FIG. 1 and the subsequent drawings are described with the Z-axis direction as the vertical direction. However, in the actual usage, the Z-axis direction may not match the vertical direction.

  The power storage element 10 is a secondary battery that can charge electricity and discharge electricity. Specifically, the electricity storage element 10 is a nonaqueous electrolyte secondary battery such as a lithium ion secondary battery. The power storage element 10 is applied to, for example, an electric vehicle (EV), a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), or the like. 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. Further, the power storage element 10 may be a primary battery.

  As shown in FIG. 1, the electricity storage device 10 includes a container 100, a positive electrode terminal 200, and a negative electrode terminal 300. As shown in FIG. 2, an electrode body 400 is accommodated inside the container 100, and a lid structure 180 is disposed above the electrode body 400.

  The lid structure 180 includes the lid plate 110 of the container 100, a current collector, and an insulating member. Specifically, the lid structure 180 includes a positive electrode current collector 140 that is electrically connected to a tab bundle 410 (tab portion) on the positive electrode side of the electrode body 400 as the current collector. Similarly, the lid structure 180 includes a negative electrode current collector 150 electrically connected to a tab bundle 420 (tab portion) on the negative electrode side of the electrode body 400 as the current collector.

  The lid structure 180 has a lower insulating member 120 disposed between the lid plate 110 and the positive electrode current collector 140 as the insulating member. Similarly, the lid structure 180 includes a lower insulating member 130 disposed between the lid plate 110 and the negative electrode current collector 150 as the insulating member.

  The lid structure 180 according to the present embodiment further includes a positive electrode terminal 200, a negative electrode terminal 300, an upper insulating member 125, and an upper insulating member 135.

  The upper insulating member 125 is disposed between the lid plate 110 and the positive electrode terminal 200. The upper insulating member 135 is disposed between the lid plate 110 and the negative electrode terminal 300.

  An upper spacer 500 and a buffer sheet 600 are disposed between the lid structure 180 having the above configuration and the electrode body 400.

  The upper spacer 500 is disposed between the side of the electrode body 400 where the tab bundles 410 and 420 are provided and the lid plate 110. Specifically, the upper spacer 500 has a flat plate shape as a whole, and has two insertion portions 520 into which the tab bundles 410 and 420 are inserted. In the present embodiment, the insertion portion 520 is provided in a cutout shape in the upper spacer 500. The upper spacer 500 is made of an insulating material such as polycarbonate (PC), polypropylene (PP), polyethylene (PE), or polyphenylene sulfide resin (PPS).

  The upper spacer 500 prevents, for example, a member that directly or indirectly regulates the movement of the electrode body 400 upward (in the direction of the lid plate 110) or a short circuit between the lid structure 180 and the electrode body 400. It functions as a member.

  The buffer sheet 600 is formed of a highly flexible porous material such as foamed polyethylene, and is a member that functions as a buffer material between the electrode body 400 and the upper spacer 500.

  Further, in the present embodiment, the side surface (both side surfaces in the X-axis direction in the present embodiment) of the electrode body 400 in the direction intersecting the alignment direction (Z-axis direction) of the electrode body 400 and the cover plate 110, A side spacer 700 is disposed between the inner peripheral surface of the container 100. Thereby, the side spacer 700 is provided in the one end part of the positive electrode side (positive electrode terminal 200 side) and the other end part of the negative electrode side (negative electrode terminal 300 side) in the electrode body 400, respectively. The side spacer 700 plays a role of regulating the position of the electrode body 400, for example.

  The storage element 10 includes other elements such as a buffer sheet disposed between the electrode body 400 and the bottom 113 of the container 100 (container body 111) in addition to the elements illustrated in FIGS. May be. In addition, although an electrolytic solution (nonaqueous electrolyte) is sealed inside the container 100 of the electricity storage element 10, the illustration of the electrolytic solution is omitted.

  The container 100 is a square case and includes a container main body 111 and a lid plate 110. The material of the container body 111 and the lid plate 110 is not particularly limited, but is preferably a weldable metal such as stainless steel, aluminum, or aluminum alloy.

  The container main body 111 is a case formed in a rectangular parallelepiped shape. Specifically, the container main body 111 is a cylindrical body having a rectangular shape when viewed from above, and includes an opening 112 at one end and a bottom 113 at the other end. At the time of assembly, the electrode body 400 and the side spacer 700 are inserted into the container body 111 of the container 100 through the opening 112. A direction in which the electrode body 400 and the side spacer 700 are inserted into the opening 112 is defined as an insertion direction (Z-axis direction). Specifically, the side spacer 700 is interposed between the short side surface of the container body 111 and the electrode body 400.

  An insulating sheet 350 that covers the electrode body 400 is disposed inside the container body 111. In FIG. 2, the developed insulating sheet 350 is shown. The insulating sheet 350 is formed in a long rectangular shape with an insulating material such as PC, PP, PE, or PPS. The insulating sheet 350 is fixed in a state of being wound around the electrode body 400 and the side spacer 700 and is accommodated in the container main body 111. The fixed state of the insulating sheet 350 will be described later.

  The container main body 111 is sealed by the electrode plate 400, the insulating sheet 350, and the like being accommodated therein and then the lid plate 110 being welded or the like.

  The lid plate 110 is a plate-like member that closes the opening 112 of the container body 111. As shown in FIGS. 2 and 3, the cover plate 110 is formed with a gas discharge valve 170, a liquid injection port 117, through holes 110 a and 110 b, and two bulging portions 160. The gas discharge valve 170 has a role of releasing the gas inside the container 100 by being opened when the internal pressure of the container 100 increases.

  The liquid injection port 117 is a through-hole for injecting an electrolytic solution when the power storage element 10 is manufactured. In addition, an infusion plug 118 is arranged on the lid plate 110 so as to close the infusion port 117. That is, at the time of manufacturing the electricity storage device 10, the electrolytic solution is injected into the container 100 from the liquid injection port 117, the liquid injection plug 118 is welded to the lid plate 110, and the liquid injection port 117 is closed. Housed inside.

  In addition, as long as it does not impair the performance of the electrical storage element 10, as the electrolyte solution enclosed with the container 100, there is no restriction | limiting in particular and various things can be selected.

  In the present embodiment, each of the two bulging portions 160 is provided on the lid plate 110 by forming a part of the lid plate 110 in a bulging shape. For example, the upper insulating member 125 or 135 is provided. Used for positioning. Further, a concave portion (not shown) that is a concave portion is formed on the back side of the bulging portion 160, and the engaging protrusion 120b or 130b of the lower insulating member 120 or 130 is engaged with a part of the concave portion. Match. Thereby, the lower insulating member 120 or 130 is also positioned and fixed to the lid plate 110 in that state.

  The upper insulating member 125 is a member that electrically insulates the positive electrode terminal 200 and the cover plate 110. The lower insulating member 120 is a member that electrically insulates the positive electrode current collector 140 from the lid plate 110. The upper insulating member 135 is a member that electrically insulates the negative electrode terminal 300 from the lid plate 110. The lower insulating member 130 is a member that electrically insulates the negative electrode current collector 150 from the lid plate 110. The upper insulating members 125 and 135 may be called, for example, an upper gasket, and the lower insulating members 120 and 130 may be called, for example, a lower gasket. That is, in the present embodiment, the upper insulating members 125 and 135 and the lower insulating members 120 and 130 also have a function of sealing between the electrode terminal (200 or 300) and the container 100.

  The upper insulating members 125 and 135 and the lower insulating members 120 and 130 are formed of an insulating material such as PC, PP, PE, or PPS, for example, like the upper spacer 500.

  As shown in FIG. 3, an engaging protrusion 130 b that engages with the bulging portion 160 protrudes from the upper surface of the lower insulating member 130. Further, a recess is formed on the lower surface of the lower insulating member 130, and the negative electrode current collector 150 is accommodated in the recess. A through hole 130 a communicating with the through hole 150 a of the negative electrode current collector 150 is formed at one end of the lower insulating member 130. The fastening portion 310 of the negative electrode terminal 300 is inserted into the through holes 130a and 150a.

  On the upper surface of the lower insulating member 120, an engagement protrusion 120b that engages with the bulging portion 160 protrudes. A recess is formed in the lower surface of the lower insulating member 120, and the positive electrode current collector 140 is accommodated in the recess. A through hole 120 a communicating with the through hole 140 a of the positive electrode current collector 140 is formed at one end of the lower insulating member 120. The fastening portion 210 of the positive terminal 200 is inserted into the through holes 120a and 140a. Further, a through hole 126 that guides the electrolyte flowing from the liquid injection port 117 toward the electrode body 400 is provided in a portion of the lower insulating member 120 that is located immediately below the liquid injection port 117.

  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 lead the electricity stored in the electrode body 400 to the external space of the power storage element 10, and in order to store the electricity in the electrode body 400, It is an electrode terminal made of metal for introducing. The positive electrode terminal 200 and the negative electrode terminal 300 are made of metal such as aluminum or aluminum alloy.

  In addition, the positive terminal 200 is provided with a fastening portion 210 that fastens the container 100 and the positive current collector 140. The negative electrode terminal 300 is provided with a fastening portion 310 that fastens the container 100 and the negative electrode current collector 150.

  The fastening portion 210 is a shaft 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 caulked. Specifically, the fastening portion 210 is inserted into the through hole 125 a of the upper insulating member 125, the through hole 110 a of the cover plate 110, the through hole 120 a of the lower insulating member 120, and the through hole 140 a of the positive electrode current collector 140. It is squeezed. Accordingly, 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 cover plate 110 together with the positive electrode terminal 200, the upper insulating member 125, and the lower insulating member 120.

  The fastening portion 310 is a shaft 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 caulked. Specifically, the fastening portion 310 is inserted into the through hole 135 a of the upper insulating member 135, the through hole 110 b of the lid plate 110, the through hole 130 a of the lower insulating member 130, and the through hole 150 a of the negative electrode current collector 150. It is squeezed. 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 cover plate 110 together with the negative electrode terminal 300, the upper insulating member 135, and the lower insulating member 130.

  The fastening portion 310 may be formed as an integral part of the negative electrode terminal 300, and the fastening portion 310 manufactured as a separate component from the negative electrode terminal 300 is fixed to the negative electrode terminal 300 by a method such as caulking or welding. It may be done. The fastening portion 310 may be formed of a metal made of a material different from that of the negative electrode terminal 300, such as copper or a copper alloy. The same applies to the relationship between the fastening portion 210 and the positive electrode terminal 200.

  The positive electrode current collector 140 is a member that is disposed between the electrode body 400 and the container 100 and electrically connects the electrode body 400 and the positive electrode terminal 200. The positive electrode current collector 140 is formed of a metal such as aluminum or an aluminum alloy. Specifically, the positive electrode current collector 140 is electrically connected to the tab bundle 410 on the positive electrode side of the electrode body 400 and electrically connected to the fastening portion 210 of the positive electrode terminal 200.

  The negative electrode current collector 150 is a member that is disposed between the electrode body 400 and the container 100 and electrically connects the electrode body 400 and the negative electrode terminal 300. The negative electrode current collector 150 is made of a metal such as copper or a copper alloy. Specifically, the negative electrode current collector 150 is electrically connected to the tab bundle 420 on the negative electrode side of the electrode body 400 and also electrically connected to the fastening portion 310 of the negative electrode terminal 300.

  Next, the configuration of the electrode body 400 will be described with reference to FIG.

  FIG. 4 is a perspective view showing the configuration of the electrode body 400 according to the embodiment. In FIG. 4, a part of the wound state of the electrode body 400 is shown in a developed manner.

  The electrode body 400 is a power storage element (power generation element) that can store electricity. The electrode body 400 is formed by alternately stacking and winding positive electrodes 450 and negative electrodes 460 and separators 470a and 470b. That is, the electrode body 400 is formed by laminating the positive electrode 450, the separator 470a, the negative electrode 460, and the separator 470b in this order, and winding the cross section into an oval shape.

The positive electrode 450 is an electrode plate in which a positive electrode active material layer is formed on the surface of a positive electrode base material layer that is a long strip-shaped metal foil made of aluminum or an aluminum alloy. In addition, as a positive electrode active material used for a positive electrode active material layer, if it is a positive electrode active material which can occlude / release lithium ion, a well-known material can be used suitably. For example, as a positive electrode active material, a polyanion compound such as LiMPO ₄ , LiMSiO ₄ , LiMBO ₃ (M is one or more transition metal elements selected from Fe, Ni, Mn, Co, etc.), lithium titanate, Spinel compounds such as lithium manganate, lithium transition metal oxides such as LiMO ₂ (M is one or more transition metal elements selected from Fe, Ni, Mn, Co, etc.) and the like can be used.

The negative electrode 460 is an electrode plate in which a negative electrode active material layer is formed on the surface of a negative electrode base material layer that is a long strip-shaped metal foil made of copper or a copper alloy. In addition, as a negative electrode active material used for a negative electrode active material layer, if it is a negative electrode active material which can occlude-release lithium ion, a well-known material can be used suitably. For example, as the negative electrode active material, lithium metal, lithium alloy (lithium metal-containing alloys such as lithium-aluminum, lithium-lead, lithium-tin, lithium-aluminum-tin, lithium-gallium, and wood alloy), and lithium can be used. Alloys that can be occluded / released, carbon materials (eg, graphite, non-graphitizable carbon, graphitizable carbon, low-temperature calcined carbon, amorphous carbon, etc.), metal oxides, lithium metal oxides (Li ₄ Ti ₅ O _12, etc.) ) And polyphosphoric acid compounds.

  The separators 470a and 470b are microporous sheets made of resin. In addition, as a material of the separators 470a and 470b used for the electrical storage element 10, a well-known material can be used suitably as long as the performance of the electrical storage element 10 is not impaired.

  The positive electrode 450 has a plurality of tabs 411 protruding outward at one end in the winding axis direction. Similarly, the negative electrode 460 includes a plurality of tabs 421 protruding outward at one end in the winding axis direction. The plurality of tabs 411 and the plurality of tabs 421 are portions where the active material is not applied and the base material layer is exposed (active material layer non-forming portion).

  The winding axis is an imaginary axis that becomes a central axis when winding the positive electrode 450, the negative electrode 460, and the like. In the present embodiment, the winding axis is parallel to the Z-axis direction passing through the center of the electrode body 400. It is a straight line.

  The plurality of tabs 411 and the plurality of tabs 421 are arranged on the same end in the winding axis direction (end on the plus side in the Z-axis direction in FIG. 4), and the positive electrode 450 and the negative electrode 460 are stacked to form an electrode. The body 400 is laminated at a predetermined position. Specifically, the plurality of tabs 411 are stacked at predetermined positions in the circumferential direction at one end in the winding axis direction by stacking the positive electrodes 450 by winding. The plurality of tabs 421 are stacked at a predetermined circumferential position different from the position where the plurality of tabs 411 are stacked at one end in the winding axis direction by stacking the negative electrode 460 by winding. .

  As a result, a tab bundle 410 formed by stacking a plurality of tabs 411 and a tab bundle 420 formed by stacking a plurality of tabs 421 are formed on the electrode body 400. The tab bundle 410 is gathered toward the center in the stacking direction, for example, and joined to the positive electrode current collector 140 by, for example, ultrasonic welding. Further, the tab bundle 420 is gathered toward the center in the stacking direction, for example, and joined to the negative electrode current collector 150 by, for example, ultrasonic welding.

  The tab bundle (410 and 420) is a portion for introducing and deriving electricity in the electrode body 400, and may be given other names such as “lead (part)” and “current collector”. is there.

  Here, since the tab bundle 410 is formed by laminating the tabs 411 that are portions where the base material layer is exposed, the tab bundle 410 does not contribute to power generation. Similarly, since the tab bundle 420 is formed by laminating the tabs 421 that are portions where the base material layer is exposed, the tab bundle 420 does not contribute to power generation. On the other hand, the portions of the electrode body 400 that are different from the tab bundles 410 and 420 are formed by laminating portions of the base material layer coated with the active material, and thus contribute to power generation. Hereinafter, this part is referred to as a main body part 430. Both end portions in the X-axis direction of the main body 430 are curved portions 431 and 432 whose outer peripheral surfaces are curved. Further, a portion between the curved portions 431 and 432 in the electrode body 400 becomes a flat portion 433 having a flat outer surface. Thus, the electrode body 400 is formed in an oval shape in which the flat portion 433 is disposed between the two curved portions 431 and 432. The electrode body 400 is housed in the container body 111 such that the curved portion 431 faces the short side surface of the container body 111 and the flat portion 433 faces the long side surface of the container body 111.

  Next, a specific configuration of the side spacer 700 will be described. Here, the side spacer 700 on the negative electrode side is illustrated, but the configuration on the positive side spacer 700 is the same, and thus the description on the positive electrode side is omitted.

  FIG. 5 is a front view of the side spacer 700 according to the embodiment as viewed from the outside. FIG. 6 is a rear view of the side spacer 700 according to the embodiment as viewed from the inside. FIG. 7 is a side view of the side spacer 700 according to the embodiment. FIG. 8 is a top view of the side spacer 700 according to the embodiment.

  As shown in FIGS. 5 to 8, the side spacer 700 is a long member extending in the insertion direction (Z-axis direction) and is made of an insulating material such as PC, PP, PE, or PPS. Is formed. The side spacer 700 integrally includes a wall portion 710, a base portion 720 connected to the upper end portion of the wall portion 710, and a bottom portion 730 connected to the lower end portion of the wall portion 710.

  The wall portion 710 is a portion that extends along the insertion direction and covers one side portion of the electrode body 400. Specifically, the wall portion 710 covers the curved portion 432 of the electrode body 400 from the side. As shown in FIGS. 6 and 8, the inner side surface 711 of the wall portion 710 on the inner side of the container 100 is a contact surface that contacts the curved portion 432 of the electrode body 400, and is curved corresponding to the curved portion 432. It is a surface. When the side spacer 700 is assembled to the electrode body 400, the inner side surface 711 of the wall portion 710 comes into contact with the curved portion 432 of the electrode body 400.

  As shown in FIG. 8, the outer surface 712 of the wall portion 710 on the container 100 side has a pair of corners formed in an R shape corresponding to the inner shape of the container 100. Moreover, the area | region which opposes the long side surface of the container 100 among the outer side surfaces 712 becomes the fixed surface 713 to which the insulating sheet 350 is fixed.

  As shown in FIGS. 5 to 8, the base 720 includes a top plate 721 and a peripheral wall 722.

  The top plate 721 is a plate portion parallel to a plane (XY plane) intersecting the insertion direction in which a pair of adjacent corner portions has an R shape. The top plate 721 is connected to the upper end portion (one end portion) of the wall portion 710 and is a portion that covers one end portion on the opening 112 side of the electrode body 400 from above.

  A peripheral wall 722 is provided on the top surface of the top plate 721. The peripheral wall 722 is open from a portion corresponding to one side 723 of the top plate 721 and is erected from the top plate 721 along other sides of the top plate 721.

  Next, the fixed state in the insulating sheet 350 will be described.

  FIG. 9 is a front view schematically showing a state in which the insulating sheet 350 according to the embodiment is wound around the electrode body 400 and the side spacer 700. FIG. 10 is a cross-sectional view of the cut surface including the XX cut line in FIG. 9.

  As shown in FIGS. 9 and 10, the insulating sheet 350 is formed on the main body 430 of the electrode body 400 and the side spacer 700 attached to one end portion on the positive electrode side and the other end portion on the negative electrode side of the electrode body 400. On the other hand, these are wound so as to cover them from the outside. Specifically, the insulating sheet 350 is wound around the main body 430 and the side spacer 700 in a state in which one end portion 351 is disposed on the outer surface 712 of the side spacer 700 on the negative electrode side. The other end 352 of the insulating sheet 350 is disposed on the outer surface 712 of the side spacer 700 on the negative electrode side so as to overlap the one end 351. Thereby, the both sides of the main body part 430 in the Y-axis direction are covered with the insulating sheet 350 from one end part to the other end part of the main body part 430. Note that if the insulating sheet 350 is wound around the main body 430 and the side spacer 700, the main body 430 and the side spacer 700 can be restrained by the insulating sheet 350.

  The wound insulating sheet 350 is fixed to the main body 430 and the side spacer 700. Specifically, the insulating sheet 350 is welded at predetermined positions on both sides of the main body 430 and the side spacer 700 in the Y-axis direction. The insulating sheet 350 is welded with the central portion in the X-axis direction of the flat portion 433 in the main body portion 430 as a welding location 440. Further, the insulating sheet 350 is welded with the fixing surface 713 of the side spacer 700 as a welding location 750. In the present embodiment, there are three welding locations 440 and 750 on the Y axis direction plus side, and there are three welding locations 440 and 750 on the Y axis direction minus side. Moreover, the welding locations 440 and 750 have a long shape along the insertion direction. The shape and size of the welding locations 440 and 750 may be any shape as long as the insulating sheet 350 can be stably fixed.

  As described above, since the insulating sheet 350 is fixed to the main body 430 and the side spacer 700 of the electrode body 400, the positional deviation between the electrode body 400 and the side spacer 700 is regulated by the insulating sheet 350. In particular, if the insulating sheet 350 is in a tension state between the welding locations 440 and 750, the positional deviation between the electrode body 400 and the side spacer 700 can be more reliably regulated.

  Next, the manufacturing method of the electrical storage element 10 is demonstrated.

  First, the positive electrode 450 and the negative electrode 460 and the separators 470a and 470b are alternately laminated and wound to form the electrode body 400 shown in FIG.

  When the winding is completed, an adhesive tape (not shown) is attached to the flat portion 433 of the electrode body 400 so that the electrode body 400 does not expand.

  Next, the tab bundle 420 of the electrode body 400 is welded and fixed to the negative electrode current collector 150, and the tab bundle 410 of the electrode body 400 is welded and fixed to the positive electrode current collector 140. Thereby, the electrode body 400 is attached to the lid structure 180.

  Next, the side spacer 700 is attached to the main body 430 of the electrode body 400. Specifically, the side spacer 700 is attached to each of the curved portions 431 and 432 of the main body 430. After the attachment, the insulating sheet 350 is wound around the main body 430 and the side spacer 700 so as to cover the main body 430 and the side spacer 700. Then, at the welding locations 440 and 750, the insulating sheet 350 is fixed to the main body 430 and the side spacer 700 by heat welding or vibration welding.

  Next, the integrated electrode body 400 and side spacer 700 are accommodated in the container body 111 of the container 100. At this time, the electrode body 400 and the side spacer 700 are inserted from the opening 112 of the container body 111.

  FIG. 11 is a front view showing a positional relationship among the electrode body 400, the side spacer 700, and the insulating sheet 350 in the container main body 111 according to the embodiment. In FIG. 11, the container main body 111 is shown as a cross-sectional view.

  As shown in FIG. 11, the electrode body 400 is restrained by the insulating sheet 350 together with the side spacer 700 in the container main body 111. Further, in this state, the displacement of the electrode body 400 and the side spacer 700 is regulated by the insulating sheet 350.

  Next, the lid plate 110 is welded to the container main body 111 to assemble the container 100, and then an electrolyte is injected from the liquid injection port 117. Thereafter, the liquid injection plug 118 is welded to the lid plate 110 to close the liquid injection port 117, whereby the power storage element 10 is manufactured.

  As described above, according to the present embodiment, since the insulating sheet 350 is fixed to the side spacer 700 and the electrode body 400, the side spacer 700 applies the impact load acting on the electrode body to the insulating sheet 350. Will be received through. Therefore, damage to the electrode body 400 can be suppressed and impact resistance can be improved.

  In addition, since the insulating sheet 350 covers from one end to the other end of the electrode body 400, one side surface of the electrode body 400 can be protected by the insulating sheet 350.

  Since the displacement between the electrode body 400 and the side spacer 700 is suppressed by the insulating sheet 350, the electrode body 400 can be held at a predetermined position in the container 100. Here, when the electrode body 400 moves from a predetermined position in the container 100, the distance between the electrode body 400 and the cover plate 110 may be increased. When this spread occurs, there is a possibility that the joint portion between the tab bundles 410 and 420 and the current collector (the positive electrode current collector 140 and the negative electrode current collector 150) is damaged. However, if the electrode body 400 can be held at a predetermined position in the container 100, the above-described spread is less likely to occur, so that it is possible to prevent the joint portion from being damaged due to the spread.

  Further, since the insulating sheet 350 is welded to the side spacer 700 and the electrode body 400, the insulating sheet 350 is fixed to the side spacer 700 and the electrode body 400 without using a separate member for fixing them. be able to.

  In addition, since the insulating sheet 350 is fixed to each of the side spacer 700 on one end side and the side spacer 700 on the other end side of the electrode body 400, the impact load acting on the electrode body 400 is passed through the insulating sheet 350. The pair of side spacers 700 can be received. Therefore, damage to the electrode body 400 can be further suppressed.

  Further, since the insulating sheet 350 is wound around the side spacer 700 and the electrode body 400, the insulating sheet 350 can restrain the side spacer 700 and the electrode body 400. Therefore, the integrity of the side spacer 700 and the insulating sheet 350 can be enhanced, and the impact resistance can be further enhanced.

(Other embodiments)
The power storage element according to the present invention has been described based on the embodiments. However, the present invention is not limited to the above embodiment. Unless it deviates from the gist of the present invention, various modifications conceived by those skilled in the art have been applied to the above-described embodiments, or forms constructed by combining a plurality of the constituent elements described above are within the scope of the present invention. include.

  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.

  For example, the number of electrode bodies 400 included in the electricity storage element 10 is not limited to 1, and may be 2 or more. When the power storage element 10 includes a plurality of electrode bodies 400, a pair of side spacers 700 may be attached to each electrode body 400.

  In the above-described embodiment, the wound-type electrode body 400 has been described as an example. However, if the tab portion (tab bundle) is accommodated in the container main body 111 in a state of facing the opening 112, the stacked body is stacked. It may be a type of electrode body.

  Moreover, in the said embodiment, the case where the side spacer 700 was individually provided in the one end part and other end part of the electrode body 400 demonstrated and demonstrated. However, the pair of side spacers 700 may be integrally formed.

  Moreover, in the said embodiment, the case where the insulating sheet 350 was fixed by welding to the electrode body 400 and the side spacer 700 was illustrated. However, the method of fixing the insulating sheet 350 to the electrode body 400 and the side spacer 700 is not limited to welding. Examples of other fixing methods include a fixing method using an adhesive.

  Moreover, in the said embodiment, the case where the insulating sheet 350 has the function to ensure the insulation of the electrode body 400 and the container 100, and the function fixed to the side spacer 700 and the electrode body 400 is illustrated. explained. However, a dedicated sheet member that ensures insulation and a dedicated sheet member that is fixed to the side spacer 700 and the electrode body 400 may be provided. In this case, the latter sheet member may not have insulation.

  Next, a fixed state different from the fixed state of the insulating sheet 350 described in the above embodiment will be described as modified examples 1 to 3.

(Modification 1)
In the said embodiment, the case where the insulating sheet 350 was wound around the electrode body 400 and the side spacer 700 was illustrated and demonstrated. In the first modification, a case where a plurality of layers of the insulating sheet 350a are wound around the electrode body 400 and the side spacer 700 will be described.

  FIG. 12 is a cross-sectional view schematically showing a state in which the insulating sheet 350 a according to the first modification is wound around the electrode body 400 and the side spacer 700. FIG. 12 corresponds to FIG.

  As shown in FIG. 12, the insulating sheet 350 a is wound on the main body 430 and the side spacer 700 in a state where a plurality of layers (specifically, two layers) are wound around the main body 430 and the side spacer 700 of the electrode body 400. Is fixed. Each layer of the insulating sheet 350a is welded at the welding locations 440 and 750. Thereby, each layer of the insulating sheet 350a is being fixed to the welding location 440 and 750 in the integrated state.

  According to this configuration, since the insulating sheet 350a is wound around the side spacer 700 and the electrode body 400 in a plurality of layers, the integrity of the side spacer 700 and the insulating sheet 350a can be further improved. Further, since each layer of the insulating sheet 350a is fixed to the side spacer 700 and the electrode body 400, it is possible to prevent the layers of the insulating sheet 350a from varying.

  In this modification, the case where the insulating sheet 350a is wound in two layers on the electrode body 400 and the side spacer 700 is described as an example, but the insulating sheet may be wound in three or more layers. In addition, a separate insulating sheet may be wound for each layer without winding a single insulating sheet 350a in multiple layers.

(Modification 2)
In the said embodiment, the case where the insulating sheet 350 was wound around the electrode body 400 and the side spacer 700 was illustrated and demonstrated. In the second modification, a case where the insulating sheet 350b is not wound around the electrode body 400 and the side spacer 700 will be described.

  FIG. 13 is a cross-sectional view schematically showing a state in which the insulating sheet 350b according to Modification 2 is attached to the electrode body 400 and the side spacer 700. FIG. 13 corresponds to FIG.

  As shown in FIG. 13, in the second modification, a pair of insulating sheets 350b are provided. One insulating sheet 350b covers the Y axis direction minus side between the main body 430 of the electrode body 400 and the side spacer 700, and is welded to the welding locations 440 and 750 on the Y axis direction minus side. The other insulating sheet 350b covers the Y axis direction plus side of the main body 430 and the side spacer 700 of the electrode body 400, and is welded to the welding locations 440 and 750 on the Y axis direction plus side.

  In the modified example 2, since the insulating sheets are not arranged on the negative side and the positive side in the X-axis direction, the installation space for the insulating sheet in the X-axis direction can be reduced, and the installation space for the electrode body 400 is accordingly reduced. Can be secured.

(Modification 3)
In the said embodiment, the case where the insulating sheet 350 was each fixed to the electrode body 400 and a pair of side spacer 700 was illustrated and demonstrated. In the fourth modification, a case where the insulating sheet 350c is fixed only to the electrode body 400 and one side spacer 700 will be described.

  FIG. 14 is a cross-sectional view schematically showing a state in which the insulating sheet 350c according to Modification 3 is attached to the electrode body 400 and the side spacer 700. FIG. 14 corresponds to FIG.

  As shown in FIG. 14, the insulating sheet 350 c according to Modification 3 is the same as the insulating sheet 350 according to the embodiment in that it is wound around the main body 430 and the side spacer 700 of the electrode body 400. It is. However, the insulating sheet 350c according to Modification 3 is welded and fixed only to the welding location 440 of the electrode body 400 and the welding location 750 of one side spacer 700 on the positive side in the Y-axis direction.

  Also in this case, since the insulating sheet 350 is fixed to the side spacer 700 and the electrode body 400, the side spacer 700 receives an impact load acting on the electrode body 400 via the insulating sheet 350. Therefore, damage to the electrode body 400 can be suppressed and impact resistance can be improved. And in this modification 3, the frequency | count of welding can be suppressed to required minimum, and the manufacturing efficiency of the electrical storage element 10 can be improved.

  In addition, the form constructed | assembled combining the said embodiment and the said modification arbitrarily is also contained in the scope of the present invention.

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

DESCRIPTION OF SYMBOLS 10 Storage element 100 Container 110 Cover plate 110a Through-hole 110b Through-hole 111 Container main body 112 Opening 113 Bottom 117 Injection port 118 Injection plug 120 Lower insulation member 120a Through-hole 120a, 140a Through-hole 120b Engagement protrusion 125 Upper insulation member 125a Through hole 126 Through hole 130 Lower insulating member 130a Through hole 130a, 150a Through hole 130b Engaging protrusion 135 Upper insulating member 135a Through hole 140 Positive electrode current collector 140a Through hole 150 Negative electrode current collector 150a Through hole 160 Swelling portion 170 Gas Discharge valve 180 Lid structure 200 Positive electrode terminal 210 Fastening part 300 Negative electrode terminal 310 Fastening part 350, 350a, 350b, 350c Insulating sheet (sheet member)
351 One end portion 352 Other end portion 400 Electrode body 410 Tab bundle 411 Tab 420 Tab bundle 421 Tab 430 Main body portion 431 Curve portion 432 Curve portion 433 Flat portion 440, 750 Welding location 450 Positive electrode 460 Negative electrode 470a Separator 470b Separator 500 Upper spacer 520 Insertion Part 600 Buffer sheet 700 Side spacer (spacer)
710 Wall 711 Inner side 712 Outer side 713 Fixed surface 720 Base 721 Top plate 722 Perimeter wall 723 One side 730 Bottom

Claims (5)

An electrode body;
A container for housing the electrode body;
A spacer interposed between the container and the electrode body;
A sheet member fixed to the spacer and the electrode body in a state of covering from one end to the other end of the electrode body;
A power storage element. The power storage device according to claim 1, wherein the sheet member is fixed by being welded to the spacer and the electrode body. The spacer is provided on each of one end and the other end of the electrode body,
The electric storage element according to claim 1, wherein the sheet member is fixed to each of the spacer on one end side of the electrode body and the spacer on the other end side. The electric storage element according to claim 1, wherein the sheet member is wound around the electrode body and the spacer. The storage element according to claim 4, wherein the sheet member is wound in a plurality of layers with respect to the spacer and the electrode body, and is fixed to the spacer and the electrode body in each layer.

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