Manufacturing method of the electrode body

Abstract

To provide a manufacturing method of electrode body capable of reducing misalignment.SOLUTION: An electrode sheet is given with a curvature. The electrode sheet is laminated over a support medium while the electrode sheet is being folded down along the length of the electrode sheet. Multiple gripping members are lined up in the direction in which the electrode sheet falls. Each of the gripping members is configured to grip both ends of the electrode sheet and support medium in the width direction. The curvature decreases as the electrode sheet collapses. As the curvature decreases, starting from the contact area between the electrode sheet and the support medium, each of the grip members releases both ends of the support medium at the same time, and after that, grips both ends of the electrode sheet at the same time.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present disclosure relates to a method for manufacturing an electrode assembly. [Background technology]

[0002] JP 2021-030566 A (Patent Document 1) discloses a stack holding device. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-030566 Summary of the Invention [Problem to be solved by the invention]

[0004] The battery includes a power generating element. The power generating element includes an electrode body. The electrode body includes a plurality of electrode sheets. For example, the electrode body can be manufactured by stacking a plurality of electrode sheets on a flat support. Hereinafter, the term "support" refers to a platform on which a workpiece is placed, a single electrode sheet, or a laminate (an electrode body in the process of being manufactured). The laminate includes two or more electrode sheets. The term "workpiece" refers to a single electrode sheet or a laminate.

[0005] A gripping member is used to reduce misalignment of the workpiece during stacking. The gripping member fixes the stack by gripping it. When a new electrode sheet is supplied on top of the stack, the gripping member releases the stack once and then grips the new electrode sheet and the stack together. By repeating this operation, the electrode sheets are stacked up. Conventionally, the gripping member grips one end (one side) of the workpiece. The gripping member releases the entire workpiece.

[0006] The electrode sheet may have undulations (which may also be expressed as "wavy"). The undulations may be generated, for example, by press processing of the electrode sheet. When the entire electrode sheet having the undulations is released from the gripping member, the electrode sheet may repel. The repulsion of the electrode sheet may cause a force to act in a direction intersecting the stacking direction. As a result, the workpiece may become misaligned.

[0007] The present disclosure aims to reduce misalignment. [Means for solving the problem]

[0008] 1. A method for producing an electrode assembly includes the following steps (a) and (b): (a) Give curvature to the electrode sheet. (b) The electrode sheet is laminated on the support while being laid down along the length direction of the electrode sheet. A plurality of gripping members are arranged in the direction in which the electrode sheet falls. Each of the gripping members is configured to grip both ends in the width direction of the electrode sheet and the support. As the electrode sheet is tilted over, the curvature decreases. As the curvature decreases, each of the gripping members, starting from the contact portion between the electrode sheet and the support, simultaneously releases both ends of the support and then simultaneously grips both ends of the electrode sheet.

[0009] In the above "1", the electrode sheets are stacked while the R-shaped electrode sheet is returned to a flat shape. In the direction in which the electrode sheet falls, the gripping members are operated sequentially in accordance with the flattening (reduction in curvature) of the electrode sheet. During stacking, even if some of the gripping members release part of the workpiece, the remaining gripping members can grip the remaining part of the workpiece. Furthermore, the gripping members grip or release both ends of the workpiece simultaneously. It is considered that deformation of the workpiece is less likely to concentrate on one side by gripping or releasing both ends of the workpiece, rather than just one end of the workpiece. Therefore, even if the electrode sheet has undulations, misalignment can be reduced.

[0010] 2. In the method for producing an electrode assembly described in "1" above, the electrode sheet may include a current collector layer, an active material layer, and a solid electrolyte layer. In an electrode sheet having a multi-layer structure, for example, undulations tend to occur due to differences in mechanical properties between the layers.

[0011] When the electrode sheet includes a solid electrolyte layer, an electrode body for an all-solid-state battery can be produced.

[0012] The term "current collector layer" is a general term for a positive electrode current collector layer and a negative electrode current collector layer, and the term "active material layer" is a general term for a positive electrode active material layer and a negative electrode active material layer.

[0013] Hereinafter, an embodiment of the present disclosure (hereinafter, may be abbreviated as "the present embodiment") will be described. However, the present embodiment does not limit the technical scope of the present disclosure. The present embodiment is illustrative in all respects. The present embodiment is non-restrictive. The technical scope of the present disclosure encompasses all modifications within the meaning and scope equivalent to the description of the claims. For example, it is also intended from the beginning that any configuration may be extracted from the present embodiment and arbitrarily combined.

[0014] Geometric terms (e.g., "parallel," "perpendicular," "orthogonal," etc.) should not be interpreted strictly. For example, "parallel" may deviate slightly from the strict meaning of "parallel." Geometric terms may include, for example, tolerances, errors, etc. in design, work, manufacturing, etc. The dimensional relationships in each drawing may not match the actual dimensional relationships. In order to facilitate understanding of the present disclosure, the dimensional relationships (length, width, thickness, etc.) in each drawing may be changed. Furthermore, some configurations may be omitted. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is a schematic flow chart of the manufacturing method according to the present embodiment. [Diagram 2] FIG. 2 is a schematic diagram showing the application of curvature. [Diagram 3] FIG. 3 is a schematic plan view of an electrode sheet. [Figure 4] FIG. 4 is a schematic cross-sectional view of an electrode sheet. [Diagram 5] FIG. 5 is a schematic diagram showing the stacking. [Figure 6] FIG. 6 is a schematic diagram showing a gripping member. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] FIG. 1 is a schematic flow chart of the manufacturing method in this embodiment. Hereinafter, the "manufacturing method in this embodiment" may be abbreviated as "the present manufacturing method". The present manufacturing method includes "(a) imparting curvature", "(b) lamination", and "(c) manufacturing an all-solid-state battery". The present manufacturing method includes "a manufacturing method of an electrode body". The manufacturing method of an electrode body includes (a) and (b). The present manufacturing method may include "a manufacturing method of an all-solid-state battery". The manufacturing method of an all-solid-state battery includes (a) to (c).

[0017] <(a) Adding curvature> FIG. 2 is a schematic diagram showing the imparting of curvature. This manufacturing method includes imparting a curvature to the electrode sheet 10. "Imparting a curvature" can also be expressed as "R bending." For example, a transport plate 20 is prepared. The transport plate 20 has flexibility. The transport plate 20 holds the electrode sheet 10 by any method. The transport plate may hold the electrode sheet 10 by, for example, an adsorption mechanism (such as a vacuum pad), a chuck, or the like.

[0018] After the transport plate 20 holds the electrode sheet 10, the transport plate 20 is curved, thereby imparting a curvature to the electrode sheet 10.

[0019] FIG. 3 is a schematic plan view of an electrode sheet. The electrode sheet 10 is a laminate unit. The electrode sheets 10 are laminated to form an electrode body. The electrode sheet 10 may have, for example, a rectangular planar shape. In this embodiment, the x-axis direction indicates the width direction of the electrode sheet 10. The y-axis direction indicates the length direction of the electrode sheet 10. The z-axis direction indicates the thickness direction of the electrode sheet 10 or the lamination direction of the electrode body. The electrode sheet 10 may have a length of, for example, 100 to 500 mm. The electrode sheet 10 may have a width of, for example, 50 to 200 mm. The electrode sheet 10 may have a thickness of, for example, 50 to 5000 μm.

[0020] 4 is a schematic cross-sectional view of an electrode sheet. The electrode sheet 10 includes at least one of a positive electrode and a negative electrode. The electrode sheet 10 may have, for example, a multi-layer structure. The electrode sheet 10 may include, for example, a positive electrode collector layer 1, a positive electrode active material layer 2, a solid electrolyte layer 3, a negative electrode active material layer 4, and a negative electrode collector layer 5. The electrode sheet 10 may include, for example, two layers each of the positive electrode active material layer 2, the solid electrolyte layer 3, and the negative electrode active material layer 4.

[0021] The positive electrode active material layer 2 may have an area smaller than that of the negative electrode active material layer 4. The negative electrode collector layer 5 may protrude in the y-axis direction (see FIG. 3). The positive electrode collector layer 1 may protrude in the y-axis direction. The positive electrode collector layer 1 may protrude in the opposite direction to the negative electrode collector layer 5 in the y-axis direction. The protruding portions of the negative electrode collector layer 5 and the positive electrode collector layer 1 may be connected to an external terminal. Dimensional differences between layers, steps between layers, and the like may cause waviness.

[0022] The positive electrode current collector layer 1 may include, for example, Al foil. The positive electrode active material layer 2 includes a positive electrode active material. The positive electrode active material may include, for example, Li(NiCoMn)O2, Li(NiCoAl)O2, etc. The solid electrolyte layer 3 may include, for example, a sulfide solid electrolyte. The sulfide solid electrolyte may include, for example, Li3PS4, etc. The negative electrode active material layer 4 includes a negative electrode active material. The negative electrode active material may include, for example, graphite, Si, etc. The negative electrode current collector layer 5 may include, for example, Cu foil, Ni foil, etc. The difference in mechanical properties between each layer (each material) can be a cause of waviness.

[0023] The electrode sheet 10 may be manufactured by any method. For example, the electrode sheet 10 may be manufactured by alternately repeating the application of paint and the press working.

[0024] <(b) Lamination> Fig. 5 is a schematic diagram showing lamination. This manufacturing method includes laminating the electrode sheet 10 on the support 11 while laying the electrode sheet 10 down along the length direction of the electrode sheet 10. The support 11 in Fig. 5 is a laminate. Note that, at the time of the first lamination, the support 11 may be, for example, a flat table. At the time of the second lamination, the support 11 is one electrode sheet 10.

[0025] The electrode sheet 10 is transported so that one end of the electrode sheet 10 contacts the support 11 in the y-axis direction. The electrode sheet 10 is gradually returned to a flat state and is laminated on the support 11. The electrode sheet 10 is tilted along the y-axis direction. As the electrode sheet 10 is tilted, the curvature of the electrode sheet 10 decreases.

[0026] A plurality of gripping members 30 are arranged in the y-axis direction. The gripping members 30 may be arranged, for example, at equal intervals. The number of gripping members 30 is arbitrary. For example, an appropriate number is set depending on the size of the gripping members 30, the length of the electrode sheet 10, the degree of waviness, etc. Each of the plurality of gripping members 30 can operate independently.

[0027] FIG. 6 is a schematic diagram showing a gripping member. The gripping member 30 is configured to grip both ends of the electrode sheet 10 in the width direction (x-axis direction). The gripping member 30 presses both ends of the electrode sheet 10, thereby fixing the electrode sheet 10 to the support 11. The gripping member 30 may have any shape. The gripping member 30 may be, for example, claw-shaped. The claw-shaped gripping member 30 may also be referred to as, for example, a "clamp claw." The state in which the gripping member 30 presses the electrode sheet 10 is also referred to as a "clamped state." The state in which the gripping member 30 releases the electrode sheet 10 is also referred to as an "unclamped state." For example, the gripping member 30 may move away from the electrode sheet 10 in the x-axis direction to transition from the clamped state to the unclamped state. The gripping member 30 may, for example, move in a circular arc. The gripping member 30 may simultaneously grip and release both ends of the electrode sheet 10.

[0028] The multiple gripping members 30 operate sequentially in accordance with the reduction in the curvature of the electrode sheet 10 (see FIG. 5). In the y-axis direction, the multiple gripping members 30 operate sequentially from the contact portion side between the electrode sheet 10 and the support 11.

[0029] The multiple gripping members 30 may be divided into, for example, a first group 31, a second group 32, and a third group 33. One or more gripping members 30 are assigned to each group. The number of members assigned to each group is arbitrary, as long as it is one or more. Each of the first group 31 and the second group 32 may include, for example, three gripping members 30. The third group 33 may include, for example, two gripping members 30.

[0030] In the first stage 101, the first group 31 is in an unclamped state. The second group 32 and the third group 33 are in a clamped state. The second group 32 and the third group 33 grip the support 11 (laminate).

[0031] Due to the reduction in curvature, the first stage 101 transitions to a second stage 102. In the second stage 102, the first group 31 is in a clamped state. The first group 31 collectively grips the electrode sheet 10 and the support 11. The second group 32 is in an unclamped state. The third group 33 is in a clamped state. The third group 33 grips the support 11.

[0032] Due to the reduction in curvature, the second stage 102 transitions to a third stage 103. In the third stage 103, the first group 31 and the second group 32 are in a clamped state. The first group 31 and the second group 32 collectively grip the electrode sheet 10 and the support 11. The third group 33 is in an unclamped state.

[0033] Due to the reduction in the curvature, the third stage 103 transitions to a fourth stage 104. In the fourth stage, the curvature is zero. That is, the electrode sheet 10 is flat. The first group 31, the second group 32, and the third group 33 are all in a clamped state. The first group 31, the second group 32, and the third group 33 collectively grip the electrode sheet 10 and the support 11.

[0034] Through the above operations, the electrode sheet 10 becomes part of the laminate. The electrode body is completed by laminating a specified number of electrode sheets 10. The electrode body may include, for example, 2 to 100 electrode sheets 10. The periphery of the electrode body may be fixed, for example, by an adhesive tape, a curable resin, or the like.

[0035] 5 are merely examples. The sequential operation of the multiple gripping members 30 may be divided into smaller operations. For example, the eight (all) gripping members 30 may be operated sequentially one by one.

[0036] <(c) Manufacturing of all-solid-state batteries> The manufacturing method includes manufacturing an all-solid-state battery including an electrode body. For example, an external terminal is connected to the electrode body. For example, the electrode body can be housed in an exterior body. The exterior body may have any shape. The exterior body may include, for example, a metal case, a pouch made of a metal foil laminate film, or the like.

[0037] The all-solid-state battery is an example of a battery. For example, an electrode body for a liquid battery, an electrode body for a polymer battery, etc. may be manufactured by the manufacturing method of the present invention. [Explanation of symbols]

[0038] 1 positive electrode current collector layer, 2 positive electrode active material layer, 3 solid electrolyte layer, 4 negative electrode active material layer, 5 negative electrode current collector layer, 10 electrode sheet, 11 support, 20 conveying plate, 30 gripping member, 31 first group, 32 second group, 33 third group, 101 first stage, 102 second stage, 103 third stage, 104 fourth stage.

Claims

1. (a) imparting a curvature to an electrode sheet; and (b) stacking the electrode sheet on a support while laying the electrode sheet down along the length direction of the electrode sheet; Including, A plurality of gripping members are arranged in the direction in which the electrode sheet falls, Each of the gripping members is configured to grip both ends of the electrode sheet and the support in a width direction, The electrode sheet is inverted to reduce the curvature, As the curvature decreases, each of the gripping members simultaneously releases both ends of the support, one after the other, from the contact portion between the electrode sheet and the support, and then simultaneously grips both ends of the electrode sheet. A method for manufacturing an electrode assembly.

2. The electrode sheet includes a current collector layer, an active material layer, and a solid electrolyte layer. A method for producing the electrode assembly according to claim 1 .

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