JP7650418B2 - Manufacturing method of the electrode body - Google Patents

Description

This disclosure relates to a method for manufacturing an electrode assembly.

JP 2021-030566 A (Patent Document 1) discloses a laminate holding device.

JP 2021-030566 A

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

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.

The electrode sheet may have undulations (which may also be expressed as "wavy"). The undulations may be generated, for example, by pressing 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.

The purpose of this disclosure is to reduce misalignment.

1. A method for producing an electrode assembly includes the following steps (a) and (b):
(a) A curvature is imparted 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.

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

2. In the manufacturing method of the electrode body 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.

By including a solid electrolyte layer in the electrode sheet, an electrode body for an all-solid-state battery can be manufactured.

Note that "collector layer" is a general term for the positive electrode collector layer and the negative electrode collector layer. "Active material layer" is a general term for the positive electrode active material layer and the negative electrode active material layer.

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

Geometric terms (e.g., "parallel," "perpendicular," "orthogonal," etc.) should not be interpreted in a strict sense. For example, "parallel" may deviate slightly from the strict meaning of "parallel." Geometric terms may include, for example, tolerances, errors, etc. in design, operation, manufacturing, etc. The dimensional relationships in each figure may not match the actual dimensional relationships. To facilitate understanding of this disclosure, the dimensional relationships (length, width, thickness, etc.) in each figure may be changed. Furthermore, some configurations may be omitted.

FIG. 1 is a schematic flow chart of the manufacturing method according to the present embodiment. FIG. 2 is a schematic diagram showing the application of curvature. FIG. 3 is a schematic plan view of an electrode sheet. FIG. 4 is a schematic cross-sectional view of an electrode sheet. FIG. 5 is a schematic diagram showing the stacking. FIG. 6 is a schematic diagram showing the gripping member.

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

<(a) Providing curvature>
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.

After the transport plate 20 holds the electrode sheet 10, the transport plate 20 bends, imparting a curvature to the electrode sheet 10.

Figure 3 is a schematic plan view of an electrode sheet. The electrode sheet 10 is a stacking unit. The electrode sheet 10 is stacked 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 stacking direction of the electrode body. The electrode sheet 10 may have, for example, a length of 100 to 500 mm. The electrode sheet 10 may have, for example, a width of 50 to 200 mm. The electrode sheet 10 may have, for example, a thickness of 50 to 5000 μm.

Figure 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.

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, etc. may cause waviness.

The positive electrode 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 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.

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 pressing.

<(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 down the electrode sheet 10 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.

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.

A number 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 multiple gripping members 30 can operate independently.

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 called, for example, a "clamp claw". The state in which the gripping member 30 presses the electrode sheet 10 is also called a "clamped state". The state in which the gripping member 30 releases the electrode sheet 10 is also called 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 an arc. The gripping member 30 may simultaneously grip and release both ends of the electrode sheet 10.

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 side between the electrode sheet 10 and the support 11.

The multiple gripping members 30 may be divided, for example, into 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.

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 are gripping the support 11 (laminated body).

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

Due to the reduction in curvature, the second stage 102 transitions to the 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.

By decreasing 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.

By the above operations, the electrode sheet 10 becomes part of the laminate. The electrode body is completed by stacking a specified number of electrode sheets 10. The electrode body may contain, for example, 2 to 100 electrode sheets 10. The periphery of the electrode body may be fixed, for example, by adhesive tape, curable resin, etc.

Note that the first stage 101 to the fourth stage 104 in FIG. 5 are merely examples. The sequential operation of the multiple gripping members 30 may be further subdivided. For example, all eight gripping members 30 may operate sequentially one by one.

(c) Production of all-solid-state battery
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.

The all-solid-state battery is one example of a battery. For example, the manufacturing method may be used to manufacture an electrode body for a liquid-based battery, an electrode body for a polymer battery, etc.

1 Positive electrode collector layer, 2 Positive electrode active material layer, 3 Solid electrolyte layer, 4 Negative electrode active material layer, 5 Negative electrode collector layer, 10 Electrode sheet, 11 Support, 20 Transport plate, 30 Grip member, 31 First group, 32 Second group, 33 Third group, 101 First stage, 102 Second stage, 103 Third stage, 104 Fourth stage.

Claims (2)

(a) imparting a curvature to an electrode sheet; and (b) laminating the electrode sheet on a support while laying the electrode sheet down along a longitudinal 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 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. 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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