Electrode member

Abstract

The invention relates to an electrode member. The electrode member includes a base material including a resin base material and a conductive layer formed on the resin base material, and an active material layer formed on the conductive layer, and the resin base material has a recessed portion recessed inward in a thickness direction parallel to a lamination direction at a position overlapping the active material layer in the lamination direction of the base material and the active material layer.

Description

Technical Field

[0001] This disclosure relates to electrode components. Background Technology

[0002] As a conventional electrode, Japanese Patent Application Publication No. 2019-096592 discloses the following structure. This structure comprises an electrode member formed by sequentially stacking a conductive layer and an active material layer on the surface of an insulating substrate, wherein at least one of a sheet-like positive electrode member and a negative electrode member is used, and a spacer is disposed between the positive and negative electrode members, and the electrode members are wound together. The conductive layer includes a first portion coated with an active material layer and a second portion protruding from the first portion, and a through-hole penetrating in the thickness direction is provided in the second portion and a portion in the insulating substrate corresponding to the second portion. Summary of the Invention

[0003] In the manufacturing process of electrode components, a stamping process is included to adhere and fix the active material layer coated on the substrate, in which the active material layer and the substrate are clamped together by rollers and stamped. In the substrate, uncoated areas without the active material layer are formed. During the stamping process, the rollers contact the active material layer but not the uncoated areas. Therefore, in the substrate, the coated areas with the active material layer stretch due to the stamping, but the uncoated areas are difficult to stretch, resulting in a stretching difference between the coated and uncoated areas. When using a substrate including a resin component, there is a concern that this stretching difference may cause the uncoated areas to bend or wrinkle to form in the uncoated areas.

[0004] This disclosure was made in view of the aforementioned problems, and the purpose of this disclosure is to provide an electrode component capable of suppressing the formation of wrinkles and bending in uncoated areas where no active material layer is coated.

[0005] The electrode components based on this disclosure have:

[0006] The substrate includes a resin substrate and a conductive layer formed on the resin substrate; and

[0007] An active material layer formed on the conductive layer.

[0008] The resin substrate has a recessed portion at the position where it overlaps with the active material layer in the stacking direction of the substrate and the active material layer, which is recessed inward in the thickness direction parallel to the stacking direction.

[0009] According to the structure described, by forming recesses in the resin substrate in easily stretchable regions where the active material layer is formed, the thickness of the resin substrate becomes thinner, while the thickness of the conductive layer becomes thicker. Therefore, when the electrode component is stamped after the active material layer is coated, stretching in easily stretchable regions can be suppressed, thus suppressing the difference in stretching between these regions and those where the active material layer is not formed and where stretching is difficult. As a result, the generation of wrinkles and deformation into curved shapes in the difficult-to-stretch regions where the active material layer is not formed can be suppressed.

[0010] In the electrode components based on this disclosure,

[0011] The recess can also be configured to increase in depth as it moves toward the inside of the width direction orthogonal to the stacking direction.

[0012] According to the structure, the recess gradually deepens toward the center in the width direction, thereby making the change in the width direction of the electrode component smooth when it is stamped after the active material layer is coated.

[0013] In the electrode components based on this disclosure,

[0014] In the width direction orthogonal to the stacking direction, the two ends of the active material layer can be located inside the two ends of the recess.

[0015] According to the structure described, the active material layer will not extend from the recessed area into the width direction. Therefore, when the electrode component is stamped after the active material layer is coated, stretching can be more reliably suppressed in easily stretchable areas, thus reducing the difference in stretching between areas that are difficult to stretch and areas where no active material layer has been formed.

[0016] According to this disclosure, an electrode component can be provided that can suppress the generation of wrinkles and bending in uncoated areas where no active material layer is coated. Attached Figure Description

[0017] The features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will now be described with reference to the accompanying drawings, in which the same reference numerals denote the same elements.

[0018] Figure 1 This is a perspective view of the battery according to Embodiment 1.

[0019] Figure 2 This is an exploded perspective view of the battery according to Embodiment 1.

[0020] Figure 3 Observe in the direction of the arrow on line III-III Figure 1 A cross-sectional view of the battery.

[0021] Figure 4 Observe in the direction of the arrow on line IV-IV. Figure 3 A cross-sectional view of the electrode body.

[0022] Figure 5 This is a cross-sectional view of the first electrode component in Embodiment 1.

[0023] Figure 6 This is a cross-sectional view of the first electrode component in Embodiment 2. Detailed Implementation

[0024] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. Furthermore, in the embodiments shown below, the same reference numerals are used to label the same or common parts in the drawings, and their descriptions will not be repeated.

[0025] Implementation Method 1

[0026] Figure 1 This is a perspective view of the battery according to Embodiment 1. (e.g.) Figure 1 As shown, the battery 1 in Embodiment 1 is a so-called prismatic battery. Battery 1 can be configured as a rechargeable secondary battery, such as a lithium-ion battery or a nickel-metal hydride battery. Battery 1 can, for example, be used as a unit included in an energy storage module mounted in an electrified vehicle.

[0027] Figure 2 This is an exploded perspective view of the battery according to Embodiment 1. Figure 3 Observe from the direction of the arrow on line III-III Figure 1 A cross-sectional view of the battery. (e.g.) Figures 1 to 3 As shown, the battery 1 of Embodiment 1 includes an electrode body 10, a housing 20, a first external terminal 30A, a second external terminal 30B, a first connecting member 40A, and a second connecting member 40B. Furthermore, the battery 1 of Embodiment 1 includes a first sealing ring 50A, a second sealing ring 50B, a first terminal support portion 60A, a second terminal support portion 60B, an insulating member 70, and a fuse protection portion 80.

[0028] The housing 20 is conductive. The conductive parts of the housing 20 are made of a metal such as aluminum. The housing 20 houses the electrode body 10. The housing 20 also houses an electrolyte (not shown in the diagram).

[0029] The housing 20 includes a housing body 21 and a cover 22. The housing body 21 includes a bottom wall 21a and a peripheral wall 21b rising from the bottom wall 21a.

[0030] The bottom wall 21a includes a bottom body 21aa, a pressure relief valve 21ab, an outer protective membrane 21ac, and an inner protective membrane 21ad. The peripheral wall 21b rises from the bottom body 21aa. The pressure relief valve 21ab is disposed on the bottom body 21aa. The outer protective membrane 21ac covers the pressure relief valve 21ab from the outside. The inner protective membrane covers the pressure relief valve 21ab from the inside. The bottom body 21aa and the pressure relief valve 21ab are made of metal such as aluminum.

[0031] An opening is formed at the upper end of the peripheral wall 21b. The peripheral wall 21b has a generally rectangular shape when viewed from the opening direction (the normal direction of the opening surface). The opening and the bottom wall 21a are aligned in a first direction D1. The first direction D1 can also be the height direction of the battery 1 or the vertical direction. The peripheral wall 21b is made of a metal such as aluminum.

[0032] The cover 22 includes a cover body 22a, a sealing bolt 22b, a bolt cover 22c, and an insulating cover 22d.

[0033] The cover body 22a is joined to the peripheral wall 21b by welding or the like, in a manner that closes the opening of the peripheral wall 21b. The cover body 22a has a first connecting hole 22aa, a second connecting hole 22ab, and an electrolyte injection hole 22ac. The electrolyte injection hole 22ac is a through hole for injecting electrolyte into the casing body 21 during the manufacturing process of the battery 1.

[0034] The sealing plug 22b seals the injection hole 22ac. The plug cover 22c covers the injection hole 22ac and the sealing plug 22b. The insulating cover 22d covers the injection hole 22ac, the sealing plug 22b, and the plug cover 22c.

[0035] The first external terminal 30A and the second external terminal 30B are arranged to be exposed to the outside in the battery 1. The first connecting member 40A and the second connecting member 40B are conductive. At least a portion of the first connecting member 40A and the second connecting member 40B is disposed inside the housing 20.

[0036] The first external terminal 30A or the first connecting member 40A is inserted into the first connecting hole 22aa. The first external terminal 30A and the first connecting member 40A are engaged with each other. The first connecting member 40A is engaged with the electrode body 10. Thus, the first external terminal 30A is electrically connected to the electrode body 10.

[0037] The second external terminal 30B or the second connecting member 40B is inserted into the second connecting hole 22ab. The second external terminal 30B and the second connecting member 40B are engaged with each other. The second connecting member 40B is engaged with the electrode body 10. Thus, the second external terminal 30B is electrically connected to the electrode body 10.

[0038] In this embodiment, the first external terminal 30A is the positive terminal and the second external terminal 30B is the negative terminal. The first external terminal 30A and the second external terminal 30B are arranged in the second direction D2. The second direction D2 is orthogonal to the first direction D1.

[0039] A first sealing ring 50A is disposed along the first connecting hole 22aa. The first sealing ring 50A is disposed in the gap between the cover body 22a and the first external terminal 30A, sealing the gap. A second sealing ring 50B is disposed along the second connecting hole 22ab. The second sealing ring 50B is disposed in the gap between the cover body 22a and the second external terminal 30B, sealing the gap. The first sealing ring 50A and the second sealing ring 50B are electrically insulating.

[0040] The first terminal support portion 60A is engaged with the cover body 22a. The first terminal support portion 60A supports the first external terminal 30A from its outer periphery. The first terminal support portion 60A includes a first locking ring 61A and a first covering ring 62A. The first locking ring 61A extends annularly around the first connecting hole 22aa and is directly engaged with the cover body 22a. The first covering ring 62A covers the first locking ring 61A. The first locking ring 61A supports the first external terminal 30A via the first covering ring 62A. The first covering ring 62A is made of a resin member having electrical insulation or relatively weak conductivity.

[0041] The second terminal support portion 60B is engaged with the cover body 22a. The second terminal support portion 60B supports the second external terminal 30B from its outer periphery. The second terminal support portion 60B includes a second locking ring 61B and a second covering ring 62B. The second locking ring 61B extends annularly around the second connecting hole 22ab and is directly engaged with the cover body 22a. The second covering ring 62B covers the second locking ring 61B. The second locking ring 61B supports the second external terminal 30B via the second covering ring 62B. The second covering ring 62B is made of an electrically insulating resin component.

[0042] The insulating member 70 is electrically insulating. The insulating member 70 is disposed between the plurality of electrode bodies 10 and the housing 20. The insulating member 70 electrically insulates the plurality of electrode bodies 10 from the housing 20. The insulating member 70 includes an insulating bracket 71, a peripheral insulating portion 72, and a bottom insulating portion 73.

[0043] An insulating bracket 71 is disposed between the plurality of electrode bodies 10 and the cover body 22a. The insulating bracket 71 has high rigidity and is in contact with both the electrode bodies 10 and the cover body 22a. Thus, the electrode bodies 10 are fixed to the housing 20 in the first direction D1.

[0044] A peripheral insulating portion 72 is disposed between the plurality of electrode bodies 10 and the peripheral wall 21b. The peripheral insulating portion 72 is composed of a film-like component.

[0045] A bottom insulating portion 73 is disposed between each electrode body 10 and the bottom wall 21a. The bottom insulating portion 73 is composed of a film-like component. In this embodiment, the bottom insulating portion 73 is bonded to the electrode body 10. Alternatively, the bottom insulating portion 73 only covers a portion of the bottom surface of the electrode body 10. Furthermore, the bottom insulating portion 73 may also cover the entire bottom surface.

[0046] like Figure 2 As shown, the battery 1 according to this embodiment includes a plurality of electrode bodies 10. The battery 1 typically includes two electrode bodies 10. These electrode bodies 10 are arranged in a third direction D3. The third direction D3 is a direction orthogonal to both the first direction D1 and the second direction D2. Furthermore, the peripheral insulating portion 72 may integrally cover the plurality of electrode bodies 10 in a manner that fixes these electrode bodies 10 to each other.

[0047] The electrode body 10 is provided with a plurality of first electrode tabs 150A and a plurality of second electrode tabs 150B. One end of the plurality of first electrode tabs 150A is connected to the first electrode member 11A described later (see reference). Figure 4 The first conductive layer 121 (refer to) Figure 5 ) and the second conductive layer 122 (refer to Figure 5 The other ends of the plurality of first tabs 150A are joined to the first connecting structural member 40A by means of ultrasonic welding or the like.

[0048] One end of the plurality of second electrode tabs 150B is connected to the second electrode member 11B described later (see reference). Figure 4 The second substrate 100B is connected. The other ends of the plurality of second tabs 150B are joined to the second connecting structure 40B by ultrasonic welding or the like.

[0049] Figure 4 Observe from the direction of the arrow on line IV-IV Figure 3 A cross-sectional view of the electrode body. The electrode body 10 includes a first electrode member 11A, a second electrode member 11B, a separator 12, and a strip member 13. The electrode body 10 is wound such that the first electrode member 11A, the second electrode member 11B, and the separator 12 surround the winding axis Z. In this embodiment, the case of a wound electrode body is illustrated, but it is not limited to this. The electrode body 10 may also be a stacked electrode body in which the first electrode member 11A, the second electrode member 11B, and the separator 12 are stacked in one direction (e.g., the third direction D3). Furthermore, in Figure 4 In the middle, the separator 12 is schematically represented by a dashed line.

[0050] The first electrode member 11A and the second electrode member 11B have a sheet-like shape. The electrode body 10 is formed by winding the first electrode member 11A and the second electrode member 11B with one or more separators 12 between them. The first electrode member 11A is, for example, a positive electrode, and the second electrode member 11B is a negative electrode.

[0051] The first electrode component 11A includes a first substrate 100A and a first active material layer 200A. The first active material layer 200A has the same polarity as the first electrode component 11A. The first active material layer 200A is, for example, a positive electrode active material layer. As the positive electrode active material layer, a known positive electrode active material layer can be used.

[0052] A first active material layer 200A is disposed on the surface and back side of the first substrate 100A. For a detailed description of the structure of the first substrate 100A, please refer to... Figure 5 To be described later.

[0053] The second electrode component 11B includes a second substrate 100B and a second active material layer 200B. The second active material layer 200B has the same polarity as the second electrode component 11B. The second electrode component 11B is, for example, a negative electrode active material layer. As the negative electrode active material layer, a known negative electrode active material layer can be used.

[0054] The second substrate 100B is, for example, made of a copper-containing metal component such as copper foil. The second active material layer 200B is disposed on the surface and back side of the second substrate 100B.

[0055] A separator 12 is disposed between the first electrode member 11A and the second electrode member 11B. The separator 12 allows ions to move between the first electrode member 11A and the second electrode member 11B, and also separates the first electrode member 11A and the second electrode member 11B. The ions are, for example, lithium ions. The separator 12 is electrically insulating.

[0056] In the electrode body 10, a separator 12 is provided on the innermost peripheral side. Additionally, in the electrode body 10, a separator 12 is provided on the outermost peripheral side. The outer peripheral edge of the separator 12 in the winding direction DR is fixed by a strip member 13 disposed on the outer peripheral surface of the separator 12.

[0057] The separator 12 may, for example, comprise a polyolefin resin. The separator 12 may, for example, be substantially composed of a polyolefin resin. The polyolefin resin may, for example, comprise at least one selected from polyethylene (PE) and polypropylene (PP).

[0058] Figure 5 This is a cross-sectional view of the first electrode component in Embodiment 1. Figure 5 A cross-sectional view of the first electrode member 11A at a section perpendicular to the second direction.

[0059] like Figure 5 As shown, the first substrate 100A of the first electrode component 11A has a coated area R1 with a first active material layer 200A and an uncoated area R2 without the first active material layer 200A. In the first electrode component 11A, the first substrate 100A includes a first resin substrate 110 and a first conductive layer 121 and a second conductive layer 122 stacked on the first resin substrate 110.

[0060] The first resin substrate 110 has a first surface 111 and a second surface 112 in the thickness direction. Furthermore, the thickness direction is parallel to the stacking direction of the first substrate 100A and the first active material layer 200A.

[0061] The first resin substrate 110 has recesses 115 and 116 at a position where it overlaps with the first active material layer 200A in the lamination direction, recessed inward toward the thickness direction. Recess 115 is located on the first surface 111 side. Recess 116 is located on the second surface 112 side. Recesses 115 and 116 are generally U-shaped. The bottom surfaces of recesses 115 and 116 are flat in a direction orthogonal to the thickness direction.

[0062] In the width direction of the first resin substrate 110, which is orthogonal to the thickness direction (the lamination direction), the widths of the recesses 115 and 116 are greater than the width of the first active material layer 200A. Furthermore, the width direction is parallel to the first direction in the electrode body 10. The recess 115 has two ends 115c and 115d in the width direction. The recess 116 has two ends 116c and 116d in the width direction.

[0063] The first resin substrate 110 may also be made of a material with a higher rigidity than the separator 12. The first resin substrate 110 may be made of, for example, a resin composition comprising a polyamide resin, a polyester resin, or a polyolefin resin.

[0064] A first conductive layer 121 is formed on the first surface 111. More specifically, the first conductive layer 121 is formed on the first surface 111 on the recess 115 and on both outer sides of the recess 115 in the width direction. In the first conductive layer 121, the surface located on the side opposite to the side where the first resin substrate 110 is located is substantially flat. The first conductive layer 121 formed in the recess 115 is thicker than the first conductive layer 121 formed on the first surface 111 on both outer sides of the recess 115.

[0065] A second conductive layer 122 is formed on the second surface 112. More specifically, the second conductive layer 122 is formed on the second surface 112 on the recess 116 and on both outer sides of the recess 116 in the width direction. In the second conductive layer 122, the surface located on the side opposite to the side where the first resin substrate 110 is located is substantially flat. The second conductive layer 122 formed on the recess 116 is thicker than the second conductive layer 122 formed on the second surface 112 on both outer sides of the recess 116.

[0066] The first conductive layer 121 and the second conductive layer 122 are made of a metal component containing aluminum. The first conductive layer 121 and the second conductive layer 122 may also be formed on the first surface 111 and the second surface 112 by means of vapor deposition or the like. Alternatively, the first conductive layer 121 and the second conductive layer 122 may also be made of metal foil and bonded to the first surface 111 and the second surface 112 by an adhesive.

[0067] The first active material layer 200A is formed on the first conductive layer 121 and the second conductive layer 122. Specifically, the first active material layer 200A is formed on the first conductive layer 121 and the second conductive layer 122 at a position where it overlaps with the recesses 115 and 116 in the stacking direction.

[0068] The first active material layer 200A has a first portion 210A and a second portion 220A. The first portion 210A is formed on the first conductive layer 121. The second portion 220A is formed on the second conductive layer 122. The first portion 210A has two ends 210c and 210d in the width direction, and the second portion 220A has two ends 220c and 220d in the width direction.

[0069] The two ends of the first active material layer 200A are located in the width direction closer to the inner sides of the two ends of the recesses 115 and 116. Specifically, the two ends 210c and 210d of the first portion 210A are located in the width direction closer to the inner sides of the two ends 115c and 115d of the recesses 115. The two ends 220c and 220d of the second portion 220A are located in the width direction closer to the inner sides of the two ends 116c and 116d of the recesses 116.

[0070] Typically, to adhere and fix the coated active material layer to the substrate, a pair of rollers clamp the active material layer and the substrate and press them together. During this pressing, the substrate tends to stretch easily at the locations where it overlaps with the active material layer, but it is difficult to stretch in the uncoated areas where no active material layer has been formed.

[0071] Here, in the first electrode component 11A according to Embodiment 1, the first resin substrate 110 has recesses 115 and 116 in the thickness direction that are recessed in the stacking direction at the position where it overlaps with the first active material layer 200A in the stacking direction.

[0072] Therefore, in the lamination direction, in the region overlapping with the first active material layer 200A, the thickness of the first resin substrate 110 becomes thinner, while the thickness of the first conductive layer 121 and the second conductive layer 122 becomes thicker. Consequently, during the manufacturing process of the first electrode member 11A, when the first electrode member 11A is stamped after the first active material layer 200A is coated, stretching in easily stretchable areas can be suppressed. This suppresses the difference in stretching between the easily stretchable areas where the first active material layer 200A is not formed and the areas that are difficult to stretch. As a result, wrinkling and deformation into a curved shape in the difficult-to-stretch areas where the first active material layer 200A is not formed can be suppressed.

[0073] Furthermore, in the width direction, the two ends of the first active material layer 200A are located further inward than the two ends of the recesses 115 and 116. Therefore, it is possible to suppress the first active material layer 200A from protruding from the recesses 115 and 116 in the width direction. As a result, when the first electrode member 11A is stamped after the first active material layer 200A is coated, it is possible to more reliably suppress stretching in easily stretchable areas and suppress the difference in stretching between areas where the first active material layer 200A is not formed and areas that are difficult to stretch.

[0074] Implementation Method 2

[0075] Figure 6 This is a cross-sectional view of the first electrode component in Embodiment 2. (Refer to...) Figure 6 The first electrode component 11X of Embodiment 2 will be described.

[0076] like Figure 6 As shown, the first electrode member 11X in Embodiment 2 differs from the first electrode member 11 in Embodiment 1 in the shapes of the recesses 115X and 116X. The other structures are largely the same.

[0077] The recesses 115X and 116X are configured such that their depth increases as they move towards the inner side of the width direction, which is orthogonal to the lamination direction. The recesses 115X and 116X have a generally V-shaped form. As a result, in the coating area R1, the thickness of the first resin substrate 110 gradually decreases as it moves towards the valleys of the recesses 115X and 116X.

[0078] With this configuration, the first electrode member 11X of Embodiment 2 can also achieve approximately the same effect as the first electrode member 11A of Embodiment 1. In addition, through the recesses 115X and 116X, when the first electrode member 11A is stamped after the first active material layer 200A is coated, the stretching change of the first resin substrate 110 in the width direction in the coating area R1 can be made gentle by the recesses 115X and 116X.

[0079] Other variations

[0080] In embodiments 1 and 2, the case where the first substrate 100A, serving as the positive electrode, includes a first resin substrate 110, a first conductive layer 121, and a second conductive layer 122 in the first electrode member 11A, is illustrated; however, it is not limited to this. In the second electrode member 11B, serving as the negative electrode, the second substrate 100B may also be constructed substantially the same as the first substrate 100A. That is, the second substrate 100B may include a second resin substrate and a conductive layer formed on the second resin substrate. In this case, the conductive layer is made of a metal containing copper. Furthermore, a recess (second recess) that is recessed inward toward the thickness direction may be provided in the second resin substrate at a position where the active material layer overlaps with the layer in the stacking direction of the second resin substrate and the conductive layer.

[0081] In Embodiments 1 and 2, the case where the first electrode member 11A is a positive electrode and the second electrode member 11B is a negative electrode is illustrated, but the embodiment is not limited to this. Alternatively, the first electrode member 11A may be a negative electrode and the second electrode member 11B a positive electrode. In this case, each component constituting the first electrode member 11A and the second electrode member 11B uses a component with a polarity suitable for the substrate.

[0082] The embodiments disclosed herein are illustrative and not restrictive in all respects. The scope of the invention is set forth in the claims, which include all modifications within the meaning and scope equivalent to those claims.

Claims

1. An electrode component comprising: The substrate includes a resin substrate and a conductive layer formed on the resin substrate; and An active material layer is formed on the conductive layer. The resin substrate has a recessed portion at a position where it overlaps with the active material layer in the stacking direction of the substrate and the active material layer, the recess being recessed inward in the thickness direction parallel to the stacking direction.

2. The electrode component according to claim 1, The recess is configured to increase in depth as it moves toward the inside of the width direction orthogonal to the stacking direction.

3. The electrode component according to claim 1 or 2, In the width direction orthogonal to the stacking direction, the two ends of the active material layer are located inside the two ends of the recess.

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