WO2018159581A1

WO2018159581A1 - Electricity storage element

Info

Publication number: WO2018159581A1
Application number: PCT/JP2018/007148
Authority: WO
Inventors: 勇太中村; 向井　寛
Original assignee: 株式会社Ｇｓユアサ; リチウムエナジーアンドパワーゲゼルシャフトミットベシュレンクテルハフッングウントコンパニーコマンディトゲゼルシャフト
Priority date: 2017-03-03
Filing date: 2018-02-27
Publication date: 2018-09-07
Also published as: JP2020071898A

Abstract

This electricity storage element (10) is provided with an electrode body (400), a container (100) which contains the electrode body (400), and a spacer (700) which is interposed between the container (100) and the electrode body (400). The spacer (700) is provided with a projection part (720) which protrudes toward the inside of the container (100) and faces one surface (401) of the electrode body (400). This electricity storage element (10) comprises a buffering material (800); and the buffering material (800) separates the one surface (401) of the electrode body (400) and the projection part (720) from each other.

Description

Electricity storage element

The present invention relates to a power storage element.

Conventionally, as a power storage element, a power storage element in which an electrode body is accommodated in a container via a spacer is known (see, for example, Patent Document 1).

JP 2011-96660 A

In recent years, the use of a spacer having a protruding portion that covers the end of the electrode body has also been studied, but in general, the spacer has higher rigidity than the electrode body, so that the protruding portion of the spacer contacts the electrode body. If this happens, the electrode body may be damaged.

For this reason, the subject of this invention is suppressing the damage of the electrode body resulting from the contact with the protrusion part of a spacer.

In order to achieve the above object, a power storage element according to one embodiment of the present invention is a power storage element including an electrode body, a container that houses the electrode body, and a spacer that is interposed between the container and the electrode body. The spacer protrudes inward of the container and includes a protruding portion facing one surface of the electrode body. The power storage element has a buffer material. The buffer material protrudes from one surface of the electrode body. Separate the part.

According to the present invention, it is possible to suppress damage to the electrode body due to contact with the protruding portion of the spacer.

FIG. 1 is a perspective view showing an external appearance of a power storage device according to an embodiment. FIG. 2 is an exploded perspective view of the energy storage device according to the embodiment. FIG. 3 is a perspective view showing the configuration of the electrode body according to the embodiment. FIG. 4 is a rear view of the side spacer according to the embodiment as seen from the inside. FIG. 5 is a cross-sectional view of the side spacer according to the embodiment as seen from the XY plane including the VV cutting line of FIG. FIG. 6 is a cross-sectional view schematically showing an arrangement relationship of the container, the electrode body, the side spacer, and the buffer material according to the embodiment. FIG. 7 is a cross-sectional view schematically showing an arrangement relationship of the container, the electrode body, the side spacer, and the buffer material according to the first modification. FIG. 8 is a cross-sectional view schematically showing an arrangement relationship of a container, an electrode body, a side spacer, and a buffer material according to Modification 2. FIG. 9 is a cross-sectional view schematically showing an arrangement relationship of a container, an electrode body, a side spacer, and a buffer material according to Modification 3.

According to this configuration, since one surface of the electrode body and the protrusion are separated by the buffer material, contact between the electrode body and the protrusion can be suppressed. Therefore, the electrode body can be prevented from being damaged due to the contact with the protruding portion of the spacer.

In addition, the spacer has, as the protrusion, a first protrusion that faces the first surface of the electrode body, and a second protrusion that faces the second surface facing the first surface of the electrode body, The buffer material may separate the first surface of the electrode body from the first protrusion and may separate the second surface of the electrode body from the second protrusion.

According to this configuration, the first surface and the first protrusion of the electrode body are separated from each other by the buffer material, and the second surface and the second protrusion are separated from each other. Even when two are provided, the contact between the electrode body and the protruding portion can be suppressed.

The buffer material includes a first buffer material interposed between the first surface of the electrode body and the first protrusion, and a second buffer material interposed between the second surface of the electrode body and the second protrusion. A cushioning material may be included.

According to this configuration, since the first cushioning material is interposed between the first surface of the electrode body and the first projecting portion, the first surface and the first projecting portion can be reliably separated from each other. Can do. In addition, since the second cushioning material is interposed between the second surface of the electrode body and the second protrusion, the second surface and the second protrusion can be reliably separated. Therefore, the contact between the first surface of the electrode body and the first protrusion and the contact between the second surface of the electrode body and the second protrusion can be reliably suppressed.

Further, the cushioning material may include a third cushioning material interposed between the first protrusion and the container, and a fourth cushioning material interposed between the second protrusion and the container.

According to this configuration, the third buffer material interposed between the first protrusion and the container and the fourth buffer material interposed between the second protrusion and the container cause the spacer and the electrode body in the container to The backlash can be suppressed. Therefore, the impact acting on the electrode body can be further alleviated.

The buffer material includes a fifth buffer material interposed between the first surface of the electrode body and the first projecting portion or between the second surface of the electrode body and the second projecting portion, and the first projecting portion. Among the second protrusions, the sixth buffer material interposed between the protrusion provided with the fifth buffer material and the container, and the fifth buffer among the first surface and the second surface of the electrode body The surface on which the material is not provided, and may include a portion exposed from the first protrusion or the second protrusion and a seventh cushioning material interposed between the container and the container.

According to this configuration, the positional relationship between the spacer and the electrode body in the container in the predetermined direction (for example, the vertical direction) is maintained by the fifth buffer material, the sixth buffer material, and the seventh buffer material. The first surface and the first protrusion can be reliably separated from each other, and the second surface of the electrode body and the second protrusion can be reliably separated from each other. Therefore, the contact between the electrode body and the spacer can be reliably suppressed.

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, with reference to FIG. 1 and FIG. 2, a general description of the storage element 10 in the embodiment will be given.

FIG. 1 is a perspective view showing an appearance of a power storage device 10 according to the embodiment. FIG. 2 is an exploded perspective view of the energy storage device 10 according to the embodiment.

In FIG. 1 and the subsequent figures, the Z-axis direction is described as the vertical direction for convenience of explanation. However, in the actual usage, the Z-axis direction may not match the vertical direction.

The electricity 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 a moving body such as an automobile such as an electric vehicle (EV), a hybrid electric vehicle (HEV), or a plug-in hybrid electric vehicle (PHEV), a motorcycle, a watercraft, a snowmobile, an agricultural machine, and a construction machine. It is applied to a battery for driving or engine starting, a stationary power supply device used for power storage use, power supply use, and 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 shape of the electricity storage element 10 is not limited to a square shape, and may be another shape such as a cylindrical shape. Further, the power storage element 10 may be a primary battery.

1 and 2, the electricity storage element 10 includes a container 100, a positive electrode terminal 200, a negative electrode terminal 300, an electrode body 400, a side spacer 700, and a buffer material 800. Although not shown in the figure, the power storage element 10, in addition to the above components, is a positive current collector that electrically connects the positive electrode of the electrode body 400 and the positive electrode terminal 200, and the negative electrode and negative electrode terminal 300 of the electrode body 400. And a negative electrode current collector electrically connected to each other. In addition, a liquid such as an electrolytic solution (non-aqueous electrolyte) is sealed inside the container 100 of the electricity storage element 10, but the illustration of the liquid is omitted. In addition, as long as the electrolyte solution enclosed with the container 100 does not impair the performance of the electrical storage element 10, there is no restriction | limiting in particular in the kind, Various things can be selected.

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

The main body 111 is a cylindrical body having a rectangular shape when viewed from above, and has an opening 112 at one end and a bottom 113 at the other end. At the time of assembly, the electrode body 400, the side spacer 700, and the like are inserted into the main 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). The main body 111 is sealed by the lid body 110 being welded after the electrode body 400 and the like are accommodated therein.

The lid 110 is a plate-like member that closes the opening 112 of the main body 111. Although not shown in the figure, the lid 110 has a gas discharge valve and a liquid injection port. The gas discharge valve is opened when the internal pressure of the container 100 rises, thereby releasing the gas inside the container 100. The liquid injection port is an opening for injecting an electrolytic solution into the container 100.

The electrode body 400 includes a positive electrode plate, a negative electrode plate, and a separator, and is a member that can store electricity. A detailed configuration of the electrode body 400 will be described later.

The positive electrode terminal 200 is an electrode terminal electrically connected to the tab portion 410 on the positive electrode side of the electrode body 400 through a positive electrode current collector. The negative electrode terminal 300 is an electrode terminal electrically connected to the tab portion 420 on the negative electrode side of the electrode body 400 through a negative electrode current collector. 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 a metal or the like having conductivity for introducing. The positive electrode terminal 200 and the negative electrode terminal 300 are attached to the lid body 110 disposed above the electrode body 400 via an insulating gasket (not shown).

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 a direction intersecting the alignment direction (Z-axis direction) of the electrode body 400 and the lid body 110, A side spacer 700 is disposed between the inner peripheral surface of the container 100. The side spacer 700 plays a role of regulating the position of the electrode body 400, for example. The side spacer 700 is made of, for example, an insulating material such as polycarbonate (PC), polypropylene (PP), polyethylene (PE), or polyphenylene sulfide resin (PPS).

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

FIG. 3 is a perspective view showing the configuration of the electrode assembly 400 according to the embodiment. In FIG. 3, 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 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 power storage element 10, a known material can be appropriately used as long as it does not impair the performance of the power storage element 10.

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

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 protrusions 411 and the plurality of protrusions 421 are arranged at the same end in the winding axis direction (the end on the plus side in the Z-axis direction in FIG. 3), and the positive electrode 450 and the negative electrode 460 are stacked. The electrode body 400 is laminated at a predetermined position. Specifically, the plurality of protrusions 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. In addition, the plurality of protrusions 421 are stacked at a predetermined position in the circumferential direction different from the position where the plurality of protrusions 411 are stacked at one end in the winding axis direction by stacking the negative electrode 460 by winding. Is done.

As a result, the electrode body 400 is formed with a tab portion 410 formed by stacking a plurality of protrusions 411 and a tab portion 420 formed by stacking a plurality of protrusions 421. . The tab portion 410 is gathered toward the center in the stacking direction, for example, and joined to the positive electrode current collector by, for example, ultrasonic welding or resistance welding. The tab portion 420 is gathered toward the center in the stacking direction, for example, and joined to the negative electrode current collector by, for example, ultrasonic welding or resistance welding.

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

Here, since the tab portion 410 is formed by laminating the protruding portion 411 that is the portion where the base material layer is exposed, the tab portion 410 does not contribute to power generation. Similarly, since the tab part 420 is formed by laminating the protruding part 421 that is the part where the base material layer is exposed, the tab part 420 does not contribute to power generation. On the other hand, the portions of the electrode body 400 different from the

tab portions

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 portion 430 become

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.

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. 4 is a rear view of the side spacer 700 according to the embodiment as viewed from the inside. FIG. 5 is a cross-sectional view of the side spacer 700 according to the embodiment as viewed from the XY plane including the VV cutting line of FIG. In FIG. 5, the two-dot chain line indicates the curved portion 432 of the electrode body 400.

As shown in FIGS. 4 and 5, 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 is disposed so as to face a pair of short side surfaces among the inner side surfaces of the main body 111 of the container 100.

The side spacer 700 integrally includes a wall portion 710, a top plate 720 connected to the upper end portion of the wall portion 710, and a bottom plate 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, as shown in FIG. 5, the inner side surface 711 of the inner side of the container 100 in the wall portion 710 is a surface facing the curved portion 432 of the electrode body 400, and is a smooth surface corresponding to the curved portion 432. It has a curved 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 on the electrode body 400.

Also, the outer surface 712 on the container 100 side of the wall 710 has a pair of corners formed in an R shape corresponding to the inner shape of the container 100. The pair of R-shaped portions opposes a pair of adjacent corners inside the rectangular container 100. A pair of R-shaped portions in the wall portion 710 is a corner region 713, and a portion sandwiched between the pair of corner regions 713 is a central region 714. The central region 714 is a region that covers the top of the curved portion 432 of the electrode body 400, and the corner region 713 is a region that covers the side of the top of the curved portion 432.

The top plate 720 and the bottom plate 730 are plate bodies in which a pair of adjacent corners has an R shape. The top plate 720 is connected to the upper end portion (one end portion) of the wall portion 710 and is a protruding portion that protrudes from the inner side surface 711 of the wall portion 710 toward the inside of the container 100. Specifically, the top plate 720 is a first protrusion that faces the first surface (upper surface 401) on the opening 112 side of the electrode body 400 from above. The bottom plate 730 is connected to the lower end portion (the other end portion) of the wall portion 710 and is a protruding portion that protrudes from the inner side surface 711 of the wall portion 710 toward the inside of the container 100. Specifically, the bottom plate 730 is a second protrusion that faces the second surface (lower surface 402) facing the first surface of the electrode body 400 from below. In the present embodiment, the first surface (upper surface 401) and the second surface (lower surface 402) of the electrode body 400 are configured from the end surfaces of the

separators

470a and 470b that form the electrode body 400.

The cushioning material 800 is a member formed so as to have lower rigidity than the side spacer 700. Specifically, a cushioning material made of a material having a lower rigidity than the side spacer 700, for example, a cushioning material such as foamed polyethylene, or a shape lower in rigidity than the side spacer 700 is formed. And cushioning materials. One method for reducing the rigidity depending on the shape is, for example, forming a resin material in a porous manner. Examples of the resin material forming the buffer material 800 include a material having insulating properties such as PC, PP, PE, or PPS, as in the case of the side spacer 700.

FIG. 6 is a cross-sectional view schematically showing the positional relationship among the container 100, the electrode body 400, the side spacer 700, and the buffer material 800 according to the embodiment.

2 and 6, the cushioning material 800 includes a first cushioning material 810, a second cushioning material 820, a third cushioning material 830, and a fourth cushioning material 840.

The first buffer material 810 is a plate-shaped buffer material, and one buffer material is provided for each side spacer 700. The first buffer material 810 is interposed between the upper surface 401 of the electrode body 400 and the top plate 720 of the side spacer 700. Thereby, the first buffer material 810 separates the upper surface 401 of the electrode body 400 from the top plate 720 of the side spacer 700. The first buffer material 810 may have any shape as long as it can be interposed between the upper surface 401 of the electrode body 400 and the top plate 720 of the side spacer 700. In the present embodiment, the first buffer material 810 has a planar shape similar to the planar shape of the top plate 720.

The second buffer material 820 is a plate-shaped buffer material, and one buffer material is provided for each side spacer 700. The second buffer material 820 is interposed between the lower surface 402 of the electrode body 400 and the bottom plate 730 of the side spacer 700. Thereby, the second buffer material 820 separates the lower surface 402 of the electrode body 400 from the bottom plate 730 of the side spacer 700. The second buffer material 820 may have any shape as long as it can be interposed between the upper surface 401 of the electrode body 400 and the top plate 720 of the side spacer 700. In the present embodiment, the second cushioning material 820 has a planar shape similar to the planar shape of the bottom plate 730.

The third buffer material 830 is a plate-shaped buffer material, and one buffer material is provided for each side spacer 700. The third cushioning material 830 is interposed between the top plate 720 of the side spacer 700 and the lid 110 of the container 100. Thereby, the third cushioning material 830 separates the top plate 720 of the side spacer 700 and the lid 110 of the container 100. The third buffer material 830 may have any shape as long as it can be interposed between the upper surface 401 of the electrode body 400 and the top plate 720 of the side spacer 700. In the present embodiment, the third cushioning material 830 has a planar shape similar to the planar shape of the top plate 720.

The fourth buffer material 840 is a plate-shaped buffer material, and one fourth buffer material 840 is provided for each side spacer 700. The fourth buffer material 840 is interposed between the bottom plate 730 of the side spacer 700 and the bottom 113 of the main body 111 of the container 100. Thereby, the fourth buffer material 840 separates the bottom plate 730 of the side spacer 700 from the main body 111 of the container 100. The fourth buffer material 840 may have any shape that can be interposed between the lower surface 402 of the electrode body 400 and the bottom plate 730 of the side spacer 700. In the present embodiment, the fourth buffer material 840 has a planar shape similar to the planar shape of the bottom plate 730.

And the 1st shock absorbing material 810, the 2nd shock absorbing material 820, the 3rd shock absorbing material 830, and the 4th shock absorbing material 840 should just be formed in the thickness which can relieve the impact which arises in the container 100 at least. Further, the first buffer material 810, the second buffer material 820, the third buffer material 830, and the fourth buffer material 840 have a thickness that can absorb the impact to the extent that the electrode body 400 is not damaged even if an impact occurs in the container 100. More preferably, it is formed. For these thicknesses, appropriate values obtained by various experiments, simulations, and the like are employed.

Next, a method for manufacturing the electricity storage element 10 will be described.

First, in the electrode body forming step, the positive electrode 450 and the negative electrode 460 and the

separators

470a and 470b are alternately stacked and wound to form the electrode body 400 shown in FIG.

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

Next, the tab portion 420 of the electrode body 400 is welded and fixed to the negative electrode current collector, and the tab portion 410 of the electrode body 400 is welded and fixed to the positive electrode current collector.

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. At this time, the first buffer material 810 is interposed between the upper surface 401 of the electrode body 400 and the top plate 720 of the side spacer 700, and between the lower surface 402 of the electrode body 400 and the bottom plate 730 of the side spacer 700. A second cushioning material 820 is interposed.

Thereafter, the side spacer 700 and the electrode body 400 are fixed by a tape member (not shown) and integrated.

Next, the integrated electrode body 400 and side spacer 700 are inserted into the container 100 by being inserted from the opening 112 of the main body 111 of the container 100. At this time, the third cushioning material 830 is interposed between the top plate 720 of the side spacer 700 and the lid 110 of the container 100, and the bottom plate 730 of the side spacer 700 and the bottom 113 of the main body 111 of the container 100. A fourth cushioning material 840 is interposed therebetween. In addition, if the 1st shock absorbing material 810, the 2nd shock absorbing material 820, the 3rd shock absorbing material 830, and the 4th shock absorbing material 840 are previously adhere | attached on the side spacer 700, assembly | attachment of each shock absorbing material can be performed easily.

Next, the lid 110 is welded to the main body 111, the container 100 is assembled, and the electrolytic solution is injected from the injection port. Thereafter, the storage element 10 is manufactured by welding the injection plug to the lid 110 and closing the injection port.

As described above, according to the present embodiment, the upper surface 401 of the electrode body 400 and the first protrusion (the top plate 720) are separated from each other by the cushioning material 800, and the lower surface 402 and the second surface of the electrode body 400 are separated from each other. Since the protruding portion (bottom plate 730) is separated, contact between the electrode body 400 and the protruding portion can be suppressed even when two protruding portions are provided. Therefore, the electrode body 400 can be prevented from being damaged due to the contact with the protruding portion of the side spacer 700.

In addition, since the first buffer material 810 is interposed between the upper surface 401 of the electrode body 400 and the top plate 720, the upper surface 401 of the electrode body 400 and the top plate 720 can be reliably separated. Further, since the second buffer material 820 is interposed between the lower surface 402 of the electrode body 400 and the bottom plate 730, the lower surface 402 of the electrode body 400 and the bottom plate 730 can be reliably separated. Therefore, the contact between the upper surface 401 of the electrode body 400 and the top plate 720 and the contact between the lower surface 402 of the electrode body 400 and the bottom plate 730 can be reliably suppressed.

Further, the side spacer 700 and the electrode body 400 in the container 100 are provided by the third cushioning material 830 interposed between the top plate 720 and the container 100 and the fourth cushioning material 840 interposed between the bottom plate 730 and the container 100. Can be suppressed. Therefore, the impact acting on the electrode body 400 can be further alleviated.

[Modification 1]
In the above embodiment, in order to separate the side spacer 700 and the electrode body 400, the first buffer material 810 is interposed between the top plate 720 of the side spacer 700 and the upper surface 401 of the electrode body 400, and the side spacer 700. A second cushioning material 820 is interposed between the bottom plate 730 of the first electrode and the lower surface 402 of the electrode body 400. However, the side spacer 700 and the electrode body 400 can be separated from each other without necessarily interposing the buffer material between the side spacer and the electrode body. The arrangement example of the cushioning material in that case will be specifically described in Modification 1.

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.

FIG. 7 is a cross-sectional view schematically showing an arrangement relationship among the container 100, the electrode body 400, the side spacer 700, and the buffer material 800A according to the first modification. As shown in FIG. 7, the cushioning material 800 </ b> A includes a fifth cushioning material 850, a sixth cushioning material 860, and a seventh cushioning material 870.

The fifth buffer material 850 is a plate-shaped buffer material, and one fifth buffer material 850 is provided for each side spacer 700. The fifth buffer material 850 is interposed between the upper surface 401 of the electrode body 400 and the top plate 720 of the side spacer 700. Thereby, the fifth buffer material 850 separates the upper surface 401 of the electrode body 400 from the top plate 720 of the side spacer 700. That is, the fifth buffer material 850 corresponds to the first buffer material 810.

The sixth buffer material 860 is a plate-shaped buffer material, and one buffer material is provided for each side spacer 700. The sixth buffer material 860 is interposed between the upper surface 401 of the electrode body 400 and the lid body 110 of the container 100. That is, the sixth cushioning material 860 is interposed between the container 100 and the projection provided with the fifth cushioning material 850 among the first projection and the second projection of the side spacer 700. Thereby, the sixth buffer material 860 separates the upper surface 401 of the electrode body 400 from the container 100. That is, the sixth buffer material 860 corresponds to the third buffer material 830.

The seventh buffer material 870 is a plate-shaped buffer material, and one seventh buffer material 870 is provided for the electrode body 400. The seventh buffer material 870 is disposed on the lower surface 402 of the electrode body 400 between the portion exposed from the bottom plate 730 and the bottom 113 of the main body 111 of the container 100. That is, the seventh buffer material 870 is the lower surface 402 of the electrode body 400 on the side where the fifth buffer material 850 is not provided, and is exposed from the bottom plate 730 (second projecting portion). It is interposed between the portion and the container 100. The seventh buffer material 870 is set to a thickness that separates the lower surface 402 of the electrode body 400 from the bottom plate 730 of the side spacer 700 and separates the bottom 113 of the container 100 and the bottom plate 730 of the side spacer 700. . Here, “separation” includes a state in which a load from one side is not received by the other even though the separation targets are in contact with each other.

According to this configuration, the fifth buffer material 850, the sixth buffer material 860, and the seventh buffer material 870 maintain the positional relationship between the side spacer 700 and the electrode body 400 in the container 100 in a predetermined direction (for example, the vertical direction). Is done. Therefore, the upper surface 401 of the electrode body 400 and the top plate 720 of the side spacer 700 can be reliably separated from each other, and the lower surface 402 of the electrode body 400 and the bottom plate 730 of the side spacer 700 can be reliably separated from each other. Therefore, the contact between the electrode body 400 and the side spacer 700 can be reliably suppressed.

[Modification 2]
In the first modification, the case where the fifth cushioning material 850 and the sixth cushioning material 860 are disposed on the upper side (the top plate 720 side) and the seventh cushioning material 870 is disposed on the lower side (the bottom 113 side) is illustrated. In Example 2, a case where these arrangement relationships are reversed will be described.

FIG. 8 is a cross-sectional view schematically showing an arrangement relationship among the container 100, the electrode body 400, the side spacer 700, and the buffer material 800A according to the second modification. As shown in FIG. 8, the fifth buffer material 850 is interposed between the lower surface 402 of the electrode body 400 and the bottom plate 730 of the side spacer 700. The sixth buffer material 860 is interposed between the bottom plate 730 of the side spacer 700 and the bottom 113 of the main body 111 of the container 100. On the other hand, the seventh buffer material 870 is interposed between the portion of the upper surface 401 of the electrode body 400 exposed from the top plate 720 and the lid body 110 of the container 100. That is, the seventh buffer material 870 is the upper surface 401 of the upper surface 401 and the lower surface 402 of the electrode body 400 on the side where the fifth buffer material 850 is not provided, and is exposed from the top plate 720 (first protrusion). And the container 100 is interposed.

Even in this case, the positional relationship between the side spacer 700 and the electrode body 400 in the container 100 in a predetermined direction (for example, the vertical direction) can be maintained, and as a result, the contact between the electrode body 400 and the side spacer 700 is ensured. Can be suppressed.

When the seventh cushioning material 870 is disposed on the lid 110 side as in the second modification, the seventh cushioning material 870 has a shape that does not interfere with other components (lower gasket, current collector, etc.) built in the power storage element 10. It is desirable to form the buffer material 870.

[Modification 3]
In the above embodiment, when the first buffer material 810, the second buffer material 820, and the third buffer material 830 are provided one by one in each side spacer 700, that is, two in the container 100. The case has been described as an example. However, the first buffer material 810, the second buffer material 820, and the third buffer material 830 may be provided for each of the pair of side spacers 700.

FIG. 9 is a cross-sectional view schematically showing an arrangement relationship among the container 100, the electrode body 400, the side spacer 700, and the buffer material 800C according to the third modification. As shown in FIG. 9, the fourth cushioning material 840c of the cushioning material 800C has a long plate shape so as to be interposed between the lower surface 402 of the electrode body 400 and the bottom plate 730 of the pair of side spacers 700. Is formed. Thereby, the number of parts can be reduced. When the pair of side spacers 700 is handled by one fourth buffer material 840c, the fourth buffer is formed in a shape that does not interfere with other components (lower gasket, current collector, etc.) built in the storage element 10. It is desirable to form the material 840c.

Here, the fourth buffer material 840c has been described as an example, but the same applies to other buffer materials (first buffer material 810, second buffer material 820, and third buffer material 830).

(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.

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 electrical storage element 10 includes a plurality of electrode bodies 400, a pair of side spacers may be attached so as to cover the side surfaces of the plurality of electrode bodies 400 together. When a plurality of electrode bodies 400 are provided, a pair of side spacers 700 can be attached to each electrode body 400.

Further, the positional relationship between the positive electrode side tab portion 410 and the negative electrode side tab portion 420 of the electrode body 400 is not particularly limited. For example, in the wound electrode body 400, the tab portion 410 and the tab portion 420 may be disposed on opposite sides in the winding axis direction. Moreover, when the electrical storage element 10 is provided with a laminated electrode body, when viewed from the laminating direction, the positive-side tab portion and the negative-side tab portion may be provided so as to protrude in different directions. In this case, it is only necessary that the lower insulating member, the current collector, and the like are arranged at positions corresponding to the tab portion on the positive electrode side and the tab portion on the negative electrode side, respectively.

In the above embodiment, the side spacer 700 that covers the side of the electrode body 400 is described as an example of the spacer. However, any spacer may be used as long as it is interposed between the container and the electrode body. Examples of other spacers include an upper spacer interposed between the upper surface of the electrode body and the lid of the container, and a lower spacer interposed between the lower surface of the electrode body and the bottom of the container.

In the above embodiment and Modifications 1 to 3, the case where a plurality of cushioning materials are provided in the container 100 has been described as an example. However, as long as one surface of the electrode body and the protruding portion (the top plate and the bottom plate) of the side spacer are separated from each other even at one place, there may be one buffer material in the container. Thereby, even if it is one place, the contact with the protrusion part of an electrode body and a side spacer can be reduced, and the damage to the electrode body resulting from the contact with the protrusion part of a spacer can be suppressed. Moreover, the impact with respect to an electrode body can be absorbed by the elasticity of a buffer material, and damage to an electrode body can be suppressed. Note that “separate one surface of the electrode body and the protruding portion of the side spacer” includes a state in which the other does not receive a load from one side even if they are in contact with each other.

As described above, when the electrode body 400 is accommodated in the container 100 so that the winding axis is along the Z-axis direction and current is collected by the

tab portions

410 and 420 protruding from the electrode body 400, the container 100 In this case, the electrode body 400 sways and the protruding portions of the side spacers easily interfere with the electrode body. In other words, as a countermeasure against interference with the protruding portion of the side spacer, adopting a configuration in which one surface of the electrode body and the protruding portion of the side spacer are separated from each other at one place is as opposed to the electrode body 400 as described above. Is preferred.

The present invention can be applied to power storage elements such as lithium ion secondary batteries.

10 power storage element 100 container 110 lid body 400 electrode body 401 upper surface (first surface)
402 Lower surface (second surface)
700 Side spacer (spacer)
720 Top plate (first protrusion)
730 Bottom plate (second protrusion)
800, 800A, 800C Buffer material 810 First buffer material 820 Second buffer material 830

Third buffer material

840, 840c Fourth buffer material 850 Fifth buffer material 860 Sixth buffer material 870 Seventh buffer material

Claims

An electrode body;
A container for housing the electrode body;
A storage element comprising a spacer interposed between the container and the electrode body,
The spacer is
Projecting inward of the container, and having a projecting portion facing one surface of the electrode body,
The power storage element has a buffer material,
The buffer material separates one surface of the electrode body from the protruding portion.
The spacer includes, as the protruding portion, a first protruding portion that faces the first surface of the electrode body, and a second protruding portion that faces the second surface of the electrode body facing the first surface. Have
The buffer material separates the first surface of the electrode body and the first protrusion, and separates the second surface of the electrode body and the second protrusion. Power storage element.
The cushioning material is
A first cushioning material interposed between the first surface of the electrode body and the first protrusion;
The power storage device according to claim 2, further comprising a second buffer material interposed between the second surface of the electrode body and the second protrusion.
The cushioning material is
A third cushioning material interposed between the first protrusion and the container;
The power storage device according to claim 3, further comprising a fourth cushioning material interposed between the second projecting portion and the container.
The cushioning material is
A fifth cushioning material interposed between the first surface of the electrode body and the first projecting portion or between the second surface of the electrode body and the second projecting portion;
Of the first protrusion and the second protrusion, a sixth shock absorber interposed between the container provided with the protrusion provided with the fifth shock absorber, and
Of the first surface and the second surface of the electrode body, the surface on the side where the fifth cushioning material is not provided, the portion exposed from the first protrusion or the second protrusion And a seventh cushioning material interposed between the container and the container.