Method for manufacturing a solid-state battery and manufacturing apparatus for a solid-state battery

Abstract

To provide a method for manufacturing a solid battery in which a short circuit between a positive electrode layer and a negative electrode layer is unlikely to occur.SOLUTION: A manufacturing method disclosed herein includes steps (i) and (ii) in this order. The step (i) is a step of preparing a laminate including a power generating element 110 including a positive electrode layer 111, a negative electrode layer 112, and a solid electrolyte layer 113 disposed between the positive electrode layer 111 and the negative electrode layer 112, and at least one metal foil 121 disposed on at least one major surface of the power generating element 110, and the step (ii) is a step of dividing the power generating element 110 at the linear dividing position 100d and cutting at least one metal foil 121 at the dividing position 100d.SELECTED DRAWING: Figure 1C

Description

Technical Field

[0001] The present disclosure relates to a solid-state battery, a method for manufacturing a solid-state battery, and a manufacturing apparatus for a solid-state battery.

Background Art

[0002] Currently, solid-state batteries have attracted attention. A solid-state battery includes a laminate (power generation element) in which a solid electrolyte layer is disposed between a positive electrode current collector and a negative electrode current collector. When manufacturing a solid-state battery, after manufacturing a large-sized laminate including power generation elements of a large number of batteries, the laminate may be divided so as to correspond to each battery. Conventionally, various methods have been proposed for dividing a laminate.

[0003] Patent Document 1 (Japanese Patent Application Laid-Open No. 2020-61258) discloses "a laminate pressing step of pressing a laminate in which a positive electrode layer, a negative electrode layer, and a solid electrolyte layer are laminated between the positive electrode layer and the negative electrode layer, and a shearing step of punching the laminate into a predetermined shape by shearing to form a plurality of single battery parts, a method for manufacturing a solid-state battery including the steps."

[0004] Patent Document 2 (International Publication No. 2019 / 131503) discloses "a laminate forming step of forming a laminate including a first electrode layer, a second electrode layer having a polarity opposite to that of the first electrode layer, and a solid electrolyte layer interposed between the first electrode layer and the second electrode layer, and a cutting-off step of cutting off an outer peripheral end portion of the laminate, and the laminate includes a powder material, a method for manufacturing an all-solid-state battery."

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, in the method of punching out a laminate by shearing as in Patent Document 1, there is a problem that the cross section of the laminate becomes rough and a short circuit between the positive electrode layer and the negative electrode layer is likely to occur. In such a situation, one of the objects of the present disclosure is to provide a method and an apparatus for manufacturing a solid battery in which a short circuit between the positive electrode layer and the negative electrode layer is less likely to occur.

Means for Solving the Problems

[0007] One aspect of the present disclosure relates to a method for manufacturing a solid battery. The manufacturing method includes a step (i) of preparing a laminate including a power generation element including a positive electrode layer, a negative electrode layer, and a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer, and at least one metal foil disposed on at least one main surface of the power generation element, and a step (ii) of dividing the power generation element at a linear dividing position and cutting the at least one metal foil at the dividing position, in this order.

[0008] Another aspect of the present disclosure relates to an apparatus for manufacturing a solid battery. The manufacturing apparatus is an apparatus for manufacturing a solid battery, and the solid battery includes a laminate including a power generation element including a positive electrode layer, a negative electrode layer, and a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer, and at least one metal foil disposed on at least one main surface of the power generation element. The manufacturing apparatus includes a dividing mechanism for dividing the power generation element at a linear dividing position, and a cutting mechanism for cutting the at least one metal foil at the dividing position.

Advantages of the Invention

[0009] According to the present disclosure, a solid battery can be manufactured while suppressing a short circuit between the positive electrode layer and the negative electrode layer.

Brief Description of the Drawings

[0010]

Figure 1A

Figure 1B

Figure 1C

Figure 1D

Figure 1E

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Mode for Carrying Out the Invention

[0011] Hereinafter, embodiments according to the present disclosure will be described with examples, but the present disclosure is not limited to the examples described below. In the following description, specific numerical values and materials may be exemplified, but other numerical values and other materials may be applied as long as the invention according to the present disclosure can be implemented. In this specification, the description "numerical value A to numerical value B" includes the numerical values A and B and can be read as "not less than numerical value A and not more than numerical value B". In the following description, when the lower limit and the upper limit of numerical values regarding specific physical properties and conditions are exemplified, any combination of any of the exemplified lower limits and any of the exemplified upper limits can be made as long as the lower limit is not more than the upper limit.

[0012] Hereinafter, the first and second manufacturing methods for manufacturing a solid-state battery will be described. The first manufacturing method and the second manufacturing method may be referred to as "manufacturing method (M1)" and "manufacturing method (M2)", respectively, hereinafter. Examples of solid-state batteries manufactured by the manufacturing method (M1) and the manufacturing method (M2) include batteries named all-solid-state batteries, semi-solid-state batteries, pseudo-solid-state batteries, all-resin batteries, and the like.

[0013] The manufacturing method (M1) and the manufacturing method (M2) are particularly preferably used for manufacturing all-solid-state batteries. Hereinafter, embodiments of all-solid-state batteries will be mainly described. However, when manufacturing solid-state batteries other than all-solid-state batteries, the corresponding power generation elements of the solid-state batteries may be used as the power generation elements. In the following description, in descriptions other than those applicable only to specific batteries, as long as there is no contradiction in the description, "all-solid-state battery" may be read as "solid-state battery". Also, "all-solid-state battery" may be referred to as "solid-state battery" in the industry. Therefore, as long as there is no contradiction in the description, in the following description, "all-solid-state battery" may be read as "solid-state battery".

[0014] Furthermore, the present disclosure relates to a solid-state battery (for example, an all-solid-state battery) manufactured by the manufacturing method (M1) or a solid-state battery (for example, an all-solid-state battery) manufactured by the manufacturing method (M2). The split surface of the power generation element split by the splitting process described later is less likely to cause a short circuit than the split surface of the power generation element split by the shearing process. Therefore, the solid-state battery is less likely to cause a short circuit or the like even after manufacturing and has high reliability.

[0015] In this specification, examples of solid-state batteries include batteries that do not contain a liquid component as a constituent element of the electrolyte. For example, examples of solid-state batteries include batteries that do not contain a liquid component as a constituent element necessary for functioning as a battery, and more specifically, batteries that do not contain a liquid component. Here, the "liquid component" means a component that is liquid at room temperature (25°C).

[0016] (First manufacturing method (M1)) The first manufacturing method (M1) according to this embodiment is a method for manufacturing a solid-state battery (for example, an all-solid-state battery). The manufacturing method (M1) includes step (i) and step (ii) in this order. Step (i) is a step of preparing a laminate including a power generation element including a positive electrode layer, a negative electrode layer, and a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer, and at least one metal foil disposed on at least one main surface of the power generation element. Step (ii) is a step of dividing the power generation element at a linear division position and cutting the at least one metal foil at the division position.

[0017] In step (i), the at least one metal foil is disposed on one side (one main surface) or both sides (two main surfaces) of the power generation element. When the metal foil is disposed (laminated) only on one side of the power generation element, the laminate includes one metal foil. When the metal foil is disposed (laminated) on both sides of the power generation element, the laminate includes two metal foils. In step (ii), "cutting the at least one metal foil" means cutting the one metal foil disposed when the metal foil is disposed only on one side of the power generation element, and means cutting the two metal foils disposed when the metal foil is disposed on both sides of the power generation element. From one viewpoint, step (ii) is a step of dividing the power generation element at a linear division position and cutting all of the metal foils included in the laminate at the division position. Hereinafter, the step of dividing the power generation element at the division position may be referred to as the "division step", and the step of cutting the at least one metal foil at the division position may be referred to as the "cutting step".

[0018] In the manufacturing method (M1), a laminate larger than the size of the laminate used in one solid-state battery (hereinafter sometimes referred to as the "final size") is prepared in step (i). Then, the laminate is divided in step (ii). The laminate is finally divided until it reaches the final size. In a typical example, first, a laminate having a size when the final sizes are arranged in a matrix is prepared in step (i). Next, by repeating step (ii), a plurality of strip-shaped laminates are formed. Next, by repeating step (ii) for each strip-shaped laminate, a plurality of laminates of the final size are obtained. In another example, a laminate slightly larger than the final size is produced, and one laminate of the final size is obtained by dividing and removing the ends of the laminate in step (ii). The number of laminates of the final size formed from the laminate prepared in step (i) is 1 or more, or 2 or more, and may be in the range of 1 to 1000 (for example, in the range of 1 to 100 or in the range of 2 to 100). The planar shape of the laminate of the final size is not particularly limited, but is preferably a shape composed of straight sides, and may be a rectangle (square or rectangle) or a rhombus.

[0019] (Step (i)) Step (i) of the manufacturing method (M1) is a step of preparing a laminate including a power generation element including a positive electrode layer, a negative electrode layer, and a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer, and at least one metal foil disposed on at least one main surface of the power generation element. The metal foil is usually disposed so as to cover the entire surface (or substantially the entire surface) of at least one main surface (one-sided or both-sided) of the power generation element. That is, the metal foil is disposed so as to cover the linear division position.

[0020] When the metal foil is disposed only on one side of the power generation element, the metal foil may be disposed on the positive electrode layer side or the negative electrode layer side. For example, the laminate may have a laminate structure of metal foil / positive electrode layer / solid electrolyte layer / negative electrode layer, or may have a laminate structure of metal foil / negative electrode layer / solid electrolyte layer / positive electrode layer. Note that the power generation element itself is also a laminate having a laminate structure of positive electrode layer / solid electrolyte layer / negative electrode layer. When the metal foil is disposed on both sides of the power generation element, the laminate has a laminate structure of metal foil / positive electrode layer / solid electrolyte layer / negative electrode layer / metal foil. Note that these laminates may include layers other than the above layers between the layers or between the metal foil and the layers.

[0021] There is no limitation on the planar shape of the laminate prepared in step (i) and the planar shape of the laminate of the final size. For example, it may be rectangular. There is no limitation on the size of the planar shape of the laminate of the final size, and each side of the planar shape may be 1 cm or more and 50 cm or less. The planar shape of the laminate of the final size may be a size that fits within a square having a side length in the range of 1 cm to 50 cm (for example, in the range of 1 cm to 30 cm or in the range of 1 cm to 20 cm).

[0022] The thickness of the metal foil may be in the range of 1 μm to 50 μm (for example, in the range of 5 μm to 20 μm). Such a metal foil is preferably cut by shearing. The planar shape of the metal foil on which the power generation element is disposed is usually the same as or larger than the planar shape of the power generation element, but is not particularly limited. When the metal foil is also disposed on the power generation element, the planar shape of the metal foil may be the same as, smaller than, or larger than the planar shape of the power generation element.

[0023] The thickness of the power generation element may be in the range of 100 μm to 1000 μm (for example, in the range of 200 μm to 800 μm). When a power generation element with such a thickness is cut by shearing, a short circuit due to roughness of the cut surface is particularly likely to occur. The thickness of the positive electrode layer may be in the range of 50 μm to 500 μm (for example, in the range of 100 μm to 300 μm). The thickness of the solid electrolyte layer may be in the range of 10 μm to 300 μm (for example, in the range of 30 μm to 100 μm). The thickness of the negative electrode layer may be in the range of 50 μm to 500 μm (for example, in the range of 100 μm to 300 μm). The manufacturing method (M1) is preferably used for manufacturing a solid battery using a thin power generation element.

[0024] There are no particular limitations on the material and formation method of the power generation element. For example, known materials and formation methods may be applied to the materials and formation methods of the positive electrode layer, negative electrode layer, and solid electrolyte layer. Also, there are no particular limitations on the metal foil, and a metal foil used as a current collector of the solid battery may be applied. The power generation element may be formed only by the positive electrode layer, negative electrode layer, and solid electrolyte layer. Alternatively, the power generation element may include other layers as long as the power generation element can be divided in the dividing step. Examples of such other layers include a thin conductive layer composed of a material containing a conductive powder.

[0025] The step (i) of preparing the laminate may be a step of producing the laminate from materials, or may be a step of obtaining a laminate that has already been manufactured. When producing the laminate from materials, it is preferable to form the laminate by a manufacturing process including a step of pressing the materials constituting the power generation element.

[0026] In step (i), after laminating the materials of the positive electrode layer, the solid electrolyte layer, and the negative electrode layer with at least one metal foil, the laminated materials and the metal foil may be pressed together (this pressing) to prepare a laminate. For example, in an example of step (i), the material of the positive electrode layer, the material of the solid electrolyte layer, and the material of the negative electrode layer (and the metal foil as required) are laminated on the metal foil in a predetermined order, and then the laminated materials and one or two metal foils are pressed together (this pressing) to form a laminate. This forming method is preferably used when manufacturing the laminate of an all-solid-state battery. By this pressing, one or two metal foils and each layer are integrated to obtain a laminate. The pressure of this pressing may be appropriately changed according to the material, thickness, etc., and may be 50 MPa or more and 5000 MPa or less (for example, 300 MPa or more and 3000 MPa or less). When laminating the positive electrode layer on the metal foil, a metal foil serving as a positive electrode current collector is used for the metal foil. When laminating the negative electrode layer on the metal foil, a metal foil serving as a negative electrode current collector is used for the metal foil. Note that after forming the power generation element, it is also possible to integrate the power generation element and at least one metal foil to obtain a laminate.

[0027] After arranging the material of the positive electrode layer, after arranging the material of the solid electrolyte layer, or after arranging the material of the negative electrode layer, at any stage, the arranged material may be preliminarily pressed. The preliminary pressing is usually performed at a pressure lower than the pressure of the above-mentioned pressing. There is no particular limitation on the pressure of the preliminary pressing, and it may be in the range of 1 MPa to 10 MPa. In order to reduce the voids in the laminate, at least a part of the step of forming the laminate may be performed under reduced pressure.

[0028] In step (i), at least one layer (e.g., all layers) selected from the group consisting of the positive electrode layer, the solid electrolyte layer, and the negative electrode layer may be formed using a material that does not contain a liquid component (e.g., a material containing powder and not containing a liquid component). As a method of arranging the material that does not contain a liquid component (dispersion medium) in layers, an electrostatic spraying method, a squeegee film forming method, an electrostatic coating method, or the like may be used. By forming the laminate by pressing the material that does not contain a liquid component (dry method), a laminate that is easy to cut in the cutting step can be obtained.

[0029] In addition, at least one layer (e.g., all layers) selected from the group consisting of the positive electrode layer, the solid electrolyte layer, and the negative electrode layer may be formed using a mixture (e.g., slurry) containing a material constituting the layer and a liquid component. In that case, for example, each layer and the laminate can be formed by applying, drying, and pressing the mixture. Even when using a mixture containing a liquid component, a laminate that can be cut in the cutting step can be obtained by performing drying (removal of the liquid component) and / or pressing. There is no particular limitation on the liquid component, and a known liquid component (dispersion medium) used in the formation of known power generation elements may be used. Examples of the liquid component include, for example, butyl butyrate, dibutyl ether, heptane, water, ethanol, acetone, tetrahydrofuran, N-methyl-2-pyrrolidone, and the like.

[0030] As long as it can be cut in the cutting step, there is no particular limitation on the method of forming the laminate and each layer constituting the laminate. For example, any of the layers may be formed by a spraying method or other methods.

[0031] The proportion of the powdered material in at least one layer (e.g., all layers) constituting the power generation element may be 50% by mass or more, or 70% by mass or more, and may be 100% by mass or less. When there is a layer in which the proportion of the powdered material is 50% by mass or more, the brittleness of the power generation element is high and it is easy to cut in the cutting process. The proportion of the powdered material in the positive electrode layer, the proportion of the powdered material in the negative electrode layer, and the proportion of the powdered material in the solid electrolyte layer may each be within the range defined by the lower and upper limits of the above-mentioned proportion of the powdered material. The powdered material may be an inorganic material powder or a mixture of an inorganic material powder and an organic material powder.

[0032] The material of at least one layer (e.g., all layers) selected from the group consisting of the positive electrode layer, the solid electrolyte layer, and the negative electrode layer may or may not contain a binder. From the viewpoint of facilitating the cutting process, it is preferable that the material does not contain a binder or contains a small amount of binder. As long as the cutting process can be performed, the content rate of the binder in each layer may be 10% by mass or less (e.g., 5% by mass or less, 3% by mass or less), or more than that. When the material contains a binder, there is no particular limitation on the binder, and a known binder used in the formation of known power generation elements may be used. Examples of the binder include rubbers such as styrene-butadiene rubber and butylene rubber, polyvinylidene fluoride-based polymers, acrylic resins, and the like.

[0033] In addition, the materials of the layers pressed by this press may be arranged in a layered state in advance. That is, when forming the power generation element, at least one layer selected from the group consisting of the positive electrode layer, the solid electrolyte layer, and the negative electrode layer may be formed as a single layer in advance by drying and / or pressing the material. Then, the single layer may be arranged on a metal foil or another layer and subjected to this press to form a laminate.

[0034] Step (ii) typically includes step (ii-a) of dividing the power generation element at the dividing position and step (ii-b) of cutting the at least one metal foil at the dividing position. When metal foils are disposed on two main surfaces of the power generation element, in step (ii-b), the two disposed metal foils are cut. Usually, step (ii-a) is completed before step (ii-b) is completed. For example, step (ii-a) and step (ii-b) may be performed in this order, or step (ii-b) may be performed after step (ii-a) is completed. Alternatively, step (ii-b) may be started before step (ii-a) is completed, and step (ii-a) may be completed before step (ii-b) is completed.

[0035] The timing at which step (ii-a) is completed and the timing at which step (ii-b) is performed can be varied depending on the shape of the second type described later. The description of the dividing step described below can be applied to step (ii-a), and the description of the cutting step described below can be applied to step (ii-b).

[0036] (Dividing Step) The dividing step is a step of dividing the power generation element at a linear dividing position. The linear dividing position is usually linear, but may not be a straight line as long as the power generation element can be divided at the dividing position. For example, the dividing position may be a gently curved shape, or a linear shape composed of a gently curved line and a straight line, or a linear shape composed of a plurality of straight lines. From one perspective, the dividing step is a step of dividing the power generation element (laminated body) at the dividing position by bending the power generation element (laminated body) so that stress is generated at the dividing position. A groove or the like may or may not be formed in the portion of the power generation element at the dividing position before the dividing step. In the manufacturing method (M1), it is possible to divide the power generation element at the dividing position without forming a groove in the power generation element.

[0037] Note that the dividing step is performed so that the metal foil included in the laminated body is not cut. The angle at which the power generation element is bent at the dividing position is usually a minute angle. Examples of the angle will be described later.

[0038] Step (ii) is usually performed with at least a part of the laminate fixed. There is no particular limitation on the method of fixing the laminate, and as long as the laminate can be fixed, methods such as pressing the laminate with a member or a vacuum adsorption method may be used.

[0039] In step (ii), with a part (fixed part) of the laminate fixed, the power generation element may be cut at the dividing position by applying a force to the part on the opposite side of the part across the dividing position of the laminate. According to this configuration, the power generation element can be cut at the dividing position with good yield without forming a groove or the like at the dividing position. As long as the power generation element can be divided at the dividing position, there is no limitation on the fixing position. For example, an adjacent part adjacent to the dividing position may be fixed. When fixing the adjacent part, it is preferable to perform step (ii) with the whole of the adjacent part fixed. Also, as long as the power generation element can be divided at the dividing position, there is no limitation on the position where the force is applied. For example, by pushing a part on the opposite side of the fixed part across the dividing position and away from the dividing position, the power generation element can be easily divided.

[0040] Step (ii) may be performed with the laminate on the side where the force is applied being unfixed, relative to the fixed part. According to this configuration, stress can be concentrated at the dividing position, so that the power generation element can be cut at the dividing position with good yield.

[0041] (Cutting step) In the cutting step, the metal foil is cut at the above-mentioned dividing position. In a preferred example of the cutting step, the metal foil is cut by shearing. The splitting step and the cutting step are usually continuously performed within a short time. For example, the total time for performing the splitting step and the cutting step may be 1 second or less (for example, 100 mS or less).

[0042] In Patent Document 1, a laminate (power generation element) is punched into a predetermined shape by shearing to form a plurality of single battery components. However, as described above, when the laminate including the power generation element is cut by shearing, the cut surface becomes rough and short circuits are likely to occur. When the laminate includes a metal foil, short circuits due to shearing are particularly likely to occur. One reason for this is thought to be that the preferred conditions for shearing the metal foil differ from the preferred conditions for shearing the power generation element. A power generation element containing an inorganic material powder as a main material is more likely to undergo brittle fracture than a metal foil. On the other hand, since a metal foil is likely to undergo plastic deformation, it is less likely to undergo brittle fracture. Therefore, when cutting a laminate including a power generation element and a metal foil, short circuits are likely to occur, and no effective method for suppressing short circuits and cutting has been known.

[0043] Since the laminate is thin, those skilled in the art have not considered methods other than the method of shearing the laminate including the power generation element and the metal foil as a single unit at once as a matter of common general knowledge. Usually, it is considered impossible to break only the power generation element without cutting the thin metal foil. However, as a result of investigations, the inventors of the present application have newly found that it is possible to break only the power generation element while leaving the thin metal foil. Furthermore, the inventors of the present application have newly found that it is possible to suppress short circuits and divide the laminate by dividing the power generation element and cutting the metal foil. The present disclosure is based on these new findings.

[0044] Step (ii) may be performed using the first mold and the second mold with the laminate disposed on the first mold. In that case, the power generation element can be broken at the division position by pressing the portion of the laminate away from the first mold (the portion away from the division position) with the second mold. Furthermore, the metal foil can be cut at the division position by the first mold and the second mold. According to this method, it becomes easy to perform the breaking step and the cutting step continuously. When using the first mold and the second mold, the breaking step and the cutting step can be performed by a single movement of the second mold in a predetermined direction. Note that the "portion of the laminate away from the first mold" is, from another perspective, the portion of the laminate located on the side opposite to the side where the first mold exists across the division position.

[0045] For each of the first type, the second type, and the mechanism for driving them, a known punch, die, and driving mechanism of a shearing device used in a known shearing process may be used after being modified to conform to the manufacturing method (M1). Therefore, in an example of the manufacturing method (M1), it is possible to read the second type as a punch and the first type as a die. Alternatively, in an example of the manufacturing method (M1), the second type may be read as the upper die and the first type may be read as the lower die. As the manufacturing apparatus for implementing the manufacturing method (M1), an apparatus obtained by improving a known press working machine or a known shearing machine including a punch and a die as needed may be used.

[0046] Step (ii) may be performed using the first type, the second type, and a pressing member. In that case, in step (ii), with a part of the laminate fixed by the first type and the pressing member, the power generation element may be divided at the above-mentioned dividing position by pressing the part of the laminate away from the first type with the second type. By dividing the power generation element with a part of the laminate fixed, it becomes easier to divide the power generation element at the dividing position. Note that the dividing step and the cutting step can be continuously performed while maintaining the state where the adjacent part is fixed by the first type and the pressing member. Thereby, also in the cutting step, it becomes easier to cut the metal foil. There is no particular limitation on the material of the pressing member, and an elastic material (for example, rubber) may be used, or an inorganic material such as metal may be used.

[0047] The distance between the first type and the portion to which force is applied (for example, the portion pressed by the second type) may be 0.5 mm or more, 1 mm or more, 2 mm or more, or 3 mm or more. There is no particular limitation on the portion to which force is applied, and force may be applied to the portion of the laminate protruding from the first type that is farthest from the first type, or force may be applied to a portion closer to the first type than that. That is, the distance between the first type and the portion to which force is applied may be equal to or less than the distance between the portion of the laminate that is farthest from the first type and the first type.

[0048] Step (ii) may be performed on the laminate while the laminate is in an unfixed state on the side of the pressing portion of the second type rather than on the fixed part described above. For example, step (ii) may be performed on the laminate while the portion not on the first mold is in an unfixed state.

[0049] The second mold may include a shoulder for cutting the metal foil and a pressing portion for pressing the laminate. In that case, by pressing the portion of the laminate away from the first mold with the pressing portion, the power generation element can be split at the above-mentioned splitting position. Further, the metal foil can be sheared at the above-mentioned splitting position by the first mold and the shoulder.

[0050] When using the first mold and the second mold, step (ii) may be performed by rotating the second mold. For example, as described in Embodiment 1 to be described later, the second mold may be rotated around a rotation axis located at a position away from the splitting position as the rotation center. Of course, step (ii) may be performed by moving the second mold in a certain direction.

[0051] In the above manner, the laminate can be split. After the laminate is split into the final size, a solid-state battery is manufactured using it. By the manufacturing method (M1), it is possible to manufacture a solid-state battery including a laminate including a power generation element including a positive electrode layer, a negative electrode layer, and a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer, and at least one metal foil disposed on at least one main surface of the power generation element. On at least one side surface of the laminate, the power generation element may have an end face formed by a splitting process, and the at least one metal foil may have an end face formed by a cutting process (for example, a shearing process).

[0052] There is no particular limitation on the method of manufacturing a solid-state battery using the laminate obtained in step (ii), and known methods may be used. In step (i), in an example of the manufacturing method when a laminate in which a metal foil is disposed only on one side of the power generation element is prepared, first, another current collector is formed on the side of the laminate where the metal foil (current collector) is not formed, and a power generation body (laminate) including a laminated structure of metal foil / power generation element / current collector is formed. The other current collector may be a metal foil or may be formed by a vapor deposition method or the like. In step (i), when a laminate in which metal foils are disposed on both sides of the power generation element is prepared, the laminate can be used as the power generation body as it is.

[0053] Next, after connecting a positive electrode lead and / or a negative electrode lead to the obtained power generation body as necessary, the solid-state battery is obtained by housing the power generation body in an exterior body. The power generation body may be pressed in the stacking direction before or after being housed in the exterior body. The solid-state battery may include only one of the above laminates or may include a power generation body composed of a plurality of stacked laminates. When stacking a plurality of laminates, the formation of the other current collector described above may be omitted.

[0054] There is no particular limitation on the exterior body, and a known exterior body may be used. The exterior body may include a case and / or a bag-shaped body formed of a film. For example, the power generation body may be enclosed in a bag-shaped body formed of a laminated film, or the bag-shaped body enclosing the power generation body may be further housed in a case. At this time, the power generation body may be enclosed in the bag-shaped body with the inside of the bag-shaped body or the case being in a depressurized state.

[0055] (Second manufacturing method (M2)) The manufacturing method (M2) is a manufacturing method when the laminate does not include a metal foil disposed at a position corresponding to the above-described dividing position. The manufacturing method (M2) includes step (I) and step (II) in this order. Step (I) is a step of preparing a laminate that includes a power generation element including a positive electrode layer, a negative electrode layer, and a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer and does not include a metal foil. Step (II) is a step of dividing the power generation element at the dividing position by applying a force to a portion away from the dividing position so that a stress is applied to the linear dividing position in the laminate.

[0056] Except that the laminate does not include a metal foil, step (I) and step (II) of the manufacturing method (M2) can be performed in the same manner as step (i) and step (ii) of the manufacturing method (M1), and thus overlapping descriptions are omitted. For example, in step (I), after arranging the materials of each layer in a predetermined order on a metal plate or a resin plate instead of a metal foil, the laminate may be formed by press-fitting. As step (II), only the dividing step of step (ii) may be performed.

[0057] Alternatively, step (II) may be a step of dividing the power generation element at the dividing position by applying a force to a portion away from the dividing position in a state where a member is arranged so as to be in linear contact with the laminate along the linear dividing position.

[0058] Similar to the manufacturing method (M1), also in the manufacturing method (M2), by repeating step (II) a plurality of times as necessary, the laminate is divided until it reaches the final size. The obtained laminate of the final size has current collectors formed on both sides thereof as necessary, and a power generation body (laminate) having a laminated structure of current collector / power generation element / current collector is formed. Using the obtained power generation body, a solid-state battery (for example, an all-solid-state battery) is manufactured in the same manner as the manufacturing method (M1).

[0059] Examples of the components of the solid-state battery manufactured in the present embodiment will be described below. However, the following components are examples, and a solid-state battery using other components can also be manufactured by the manufacturing method of the present embodiment. Hereinafter, an example of an all-solid-state battery (particularly an all-solid-state lithium-ion battery) will be mainly described.

[0060] (Positive electrode layer) The positive electrode layer contains a positive electrode active material and may contain other components as necessary. Examples of the other components include known components used for the positive electrode in all-solid-state batteries. From the viewpoint of enhancing lithium ion conductivity in the positive electrode layer, the positive electrode layer preferably contains a solid electrolyte exhibiting lithium ion conductivity together with the positive electrode active material. The solid electrolyte is not particularly limited as long as it exhibits lithium ion conductivity, and a solid electrolyte such as that used for the solid electrolyte layer in all-solid-state batteries can be used. Usually, the positive electrode active material is used in the form of particles (powder). As described above, the positive electrode layer can be formed by compression molding the powder of the positive electrode active material or the positive electrode mixture (including the powder of the positive electrode active material and additives, etc.).

[0061] As the positive electrode active material, a material that can be used as a positive electrode active material in all-solid-state batteries can be used. In the case of all-solid-state lithium ion batteries, examples of the positive electrode active material include lithium-containing composite oxides and compounds other than oxides. Examples of the lithium-containing composite oxides include lithium cobaltate, lithium nickelate, lithium manganate, and other lithium-containing composite oxides (LiNi 0.8 Co 0.15 Al 0.05 O2, etc.). Examples of the compounds other than oxides include olivine compounds (LiMPO4), sulfur-containing compounds (Li2S, etc.). In the above formula, M represents a transition metal. The positive electrode active material may be used alone or in combination of two or more kinds.

[0062] When using a powdered positive electrode active material, the average particle size of the positive electrode active material may be, for example, 3 μm or more or 4 μm or more, and may be 15 μm or less or 11 μm or less. In this specification, the average particle size is the median diameter (D50) in the volume-based particle size distribution measured using a laser diffraction particle size distribution analyzer.

[0063] (Negative electrode layer) The negative electrode layer contains a negative electrode active material and may contain other components as necessary. Examples of such other components include known components used for the negative electrode in all-solid-state batteries. The negative electrode layer may contain a negative electrode active material and a solid electrolyte exhibiting lithium ion conductivity. Usually, the negative electrode active material is used in the form of particles (powder). As described above, the negative electrode layer can be formed by compression molding a powder of the negative electrode active material or a negative electrode binder (including a powder of the negative electrode active material and additives, etc.).

[0064] For the negative electrode active material, a material that can be used as a negative electrode active material in an all-solid-state battery can be used. In the case of an all-solid-state lithium ion battery, as the negative electrode active material, a predetermined material (such as a carbonaceous material, a single metal or alloy of a metal or semi-metal, or a compound) that can reversibly occlude and release lithium ions can be used. Examples of carbonaceous materials include graphite (natural graphite, artificial graphite, etc.), hard carbon, amorphous carbon, etc. Examples of single metals or semi-metals and alloys include lithium metal and alloys, Si single body, etc. Examples of compounds include oxides (such as titanium oxide, silicon oxide), sulfides, nitrides, hydrides, silicides (such as lithium silicide), etc. The negative electrode active material may be used alone or in combination of two or more. For example, silicon oxide and a carbonaceous material may be used in combination. As the negative electrode active material, particles containing graphite particles and amorphous carbon covering the graphite particles may be used.

[0065] When using a powdered negative electrode active material, the average particle size of the negative electrode active material may be, for example, 3 μm or more or 4 μm or more, and may also be 50 μm or less or 30 μm or less.

[0066] (Solid electrolyte layer) The solid electrolyte layer interposed between the positive electrode and the negative electrode contains a solid electrolyte that conducts charge carriers. Usually, the solid electrolyte is used in the form of particles (powder). As described above, the solid electrolyte layer can be formed by compression molding a material containing a powder of the solid electrolyte.

[0067] For the solid electrolyte, a material that can be used as a solid electrolyte in an all-solid-state battery can be employed. In the case of an all-solid-state lithium-ion battery, a substance having lithium-ion conductivity can be used as the solid electrolyte. Examples of such solid electrolytes include inorganic solid electrolytes such as sulfides (sulfide-based solid electrolytes) and hydrides (hydride-based solid electrolytes).

[0068] Examples of sulfides include Li2S-SiS2, Li2S-P2S5, Li2S-GeS2, Li2S-B2S3, Li2S-Ga2S3, Li2S-Al2S3, Li2S-GeS2-P2S5, Li2S-Al2S3-P2S5, Li2S-P2S3, Li2S-P2S3-P2S5, LiX-Li2S-P2S5, LiX-Li2S-SiS2, LiX-Li2S-B2S3 (X: I, Br, or Cl), etc. Examples of hydrides include LiBH4-LiI complex hydrides and LiBH4-LiNH2 complex hydrides, etc.

[0069] (Positive electrode current collector) Outside the positive electrode layer of the power generation element, a positive electrode current collector is usually disposed. A metal foil may be used for the positive electrode current collector. Examples of the material of the positive electrode current collector (e.g., metal foil) include aluminum, magnesium, stainless steel, titanium, iron, cobalt, zinc, tin, or alloys thereof, etc.

[0070] (Negative electrode current collector) Outside the negative electrode layer of the power generation element, a negative electrode current collector is usually disposed. A metal foil may be used for the negative electrode current collector. Examples of the material of the negative electrode current collector (e.g., metal foil) include copper, nickel, stainless steel, titanium, alloys thereof, etc. One of the positive electrode current collector and the negative electrode current collector is the metal foil included in the laminate of the manufacturing method (M1).

[0071] In the case of manufacturing a solid battery other than an all-solid-state battery, a current collector (metal foil) and a power generation element corresponding to the solid battery are used for the current collector and the power generation element. As the power generation element of a solid battery other than an all-solid-state battery, a power generation element of a known solid battery other than an all-solid-state battery may be used. As long as those power generation elements can be divided in the dividing step, they can be manufactured by the manufacturing method (M1) and the manufacturing method (M2). Examples of power generation elements that can be divided in the dividing step include power generation elements in which each of the positive electrode layer, the solid electrolyte layer, and the negative electrode layer is formed of a solid or a semi-solid. Such a power generation element may be a power generation element in which at least one layer (for example, all layers) of the positive electrode layer, the solid electrolyte layer, and the negative electrode layer is formed of a solid.

[0072] (Manufacturing Apparatus for Solid Battery) The manufacturing apparatus according to the present embodiment is a manufacturing apparatus for a solid battery (for example, an all-solid-state battery). According to this manufacturing apparatus, the manufacturing method (M1) can be easily implemented. However, the manufacturing method (M1) may be implemented by an apparatus other than the apparatus described below. Note that the matters described for the manufacturing method (M1) can also be applied to the following manufacturing apparatus, and thus duplicate explanations may be omitted. Also, the matters described for the manufacturing apparatus may be applied to the manufacturing method (M1). Note that the manufacturing method (M2) can also be implemented using the following manufacturing apparatus except that the cutting step is not performed. When implementing the manufacturing method (M2), a mechanism (for example, shoulders of the first and second molds) for performing the cutting step is unnecessary.

[0073] Hereinafter, a manufacturing apparatus (hereinafter sometimes referred to as "manufacturing apparatus (D)") capable of implementing the manufacturing method (M1) will be described. In this case, the solid battery (for example, an all-solid-state battery) includes a laminate including a power generation element including a positive electrode layer, a negative electrode layer, and a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer, and at least one metal foil disposed on at least one main surface of the power generation element. The manufacturing apparatus (D) includes a dividing mechanism that divides the power generation element at a linear dividing position, and a cutting mechanism that cuts the at least one metal foil at the dividing position.

[0074] The manufacturing apparatus (D) may include a first type and a second type that function as a splitting mechanism and a cutting mechanism. Further, the manufacturing apparatus (D) may include a drive mechanism for driving the second type (and the first type and the second type if necessary). The second type may include a pressing portion that functions as a splitting mechanism by pressing a portion of the laminate away from the first type, and a shoulder portion that functions as a cutting mechanism.

[0075] The first type and the second type may be used after being modified to be suitable for the manufacturing apparatus (D) from the die and punch used in known shearing apparatuses. For example, for the shoulder portion of the second type and the first type (particularly, the shoulder portion of the first type), the same ones as the shoulder portion of the punch and the die (particularly, the shoulder portion of the die) of known shearing apparatuses may be used.

[0076] The manufacturing apparatus (D) may further include a mechanism for rotating the second type. There is no particular limitation on the rotating mechanism, and a known mechanism may be used. For example, the manufacturing apparatus (D) may include a motor or the like that rotates the second type about its rotation axis. The manufacturing apparatus (D) may further include a pressing member for fixing the laminate to the first type.

[0077] The manufacturing apparatus (D) performs step (ii) of splitting the power generation element at a linear splitting position and cutting the at least one metal foil at the splitting position. Since step (ii) has been described above, duplicate explanations are omitted. For example, the manufacturing apparatus (D) may split the power generation element at a linear splitting position by pressing a portion of the laminate away from the first type with the second type in a state where the laminate is disposed on the first type, and cut the at least one metal foil at the splitting position with the first type and the second type.

[0078] The manufacturing apparatus (D) includes at least a drive mechanism for driving the second type. Further, the manufacturing apparatus (D) may include a feeding mechanism for feeding out the laminate as needed. Furthermore, the manufacturing apparatus (D) may include a control device for controlling these mechanisms. There are no particular limitations on these mechanisms and the control device, and mechanisms and control devices used in known shearing devices and press devices may be used, or they may be modified to be adapted to the apparatus according to this embodiment and then used. The control device (D) includes, for example, a storage device that stores a program for performing necessary processes such as process (ii), and an arithmetic processing device for executing the program.

[0079] Hereinafter, examples of embodiments according to the present disclosure will be specifically described with reference to the drawings. The manufacturing method and manufacturing apparatus described below can apply the descriptions of the above-described embodiments, and may be modified based on the above-described descriptions. Among the steps of the manufacturing method and the components of the manufacturing apparatus described below, steps and components that are not essential for the manufacturing method and manufacturing apparatus of the present disclosure may be omitted. Also, the matters described below may be applied to the above-described embodiments. Note that the following figures are schematic and are different from the actual scale. In the following figures, in order to make the figures easier to view, a part of the members may be omitted in the illustration.

[0080] (Embodiment 1) In Embodiment 1, an example of the first manufacturing method (M1) and an example of the manufacturing apparatus (D) used therefor will be described. In the following example, a manufacturing method of an all-solid-state battery including a laminate laminated in the order of metal foil / positive electrode layer / solid electrolyte layer / negative electrode layer will be described. However, an all-solid-state battery including a laminate laminated in the order of metal foil / negative electrode layer / solid electrolyte layer / positive electrode layer, or in the order of metal foil / positive electrode layer / solid electrolyte layer / negative electrode layer / metal foil, or in the order of metal foil / negative electrode layer / solid electrolyte layer / positive electrode layer / metal foil can be manufactured in the same manner. Also, solid-state batteries other than all-solid-state batteries can be manufactured in the same manner.

[0081] In the manufacturing method of Embodiment 1, first, as shown in FIG. 1A, a laminate 100 is prepared. The laminate 100 includes a power generation element 110 and a metal foil 121. The power generation element 110 includes a positive electrode layer 111, a negative electrode layer 112, and a solid electrolyte layer 113. The laminate 100 can be formed by the method described above.

[0082] Next, as shown in FIG. 1B, the laminate 100 is placed on a lower mold (first mold) 210, and the laminate 100 is sandwiched and fixed by the lower mold 210 and a pressing member 211. Specifically, an adjacent portion 100a adjacent to the dividing position 100d of the laminate 100 is fixed. Among the laminate 100, a protruding portion 100b protruding from the lower mold 210 is not fixed.

[0083] At this time, it is preferable to arrange the laminate 100 so that the metal foil 121 is located on the side opposite to the lower mold 210. Thereby, the laminate 100 can be cut with particularly good yield. However, the laminate 100 may be arranged so that the metal foil 121 is located on the side of the lower mold 210.

[0084] The lower mold 210 has a corner portion 210a extending linearly. The upper mold (second mold) 220 includes a shoulder portion 220a for cutting the metal foil 121 and a pressing portion 220b for pressing the laminate 100. The shoulder portion 220a and the pressing portion 220b each have a shape of a linearly extending corner. Note that these shapes can be changed according to the shape of the dividing position 100d. Note that the shape of the pressing portion 220b is not particularly limited as long as the dividing process can be performed. For example, the pressing portion 220b does not have to have a corner shape, and does not have to extend linearly.

[0085] The arrangement of the laminate 100 and the lower mold 210 in FIG. 1B when viewed from above is schematically shown in FIG. 2. FIG. 2 also shows an example of the arrangement of the upper mold 220. In FIG. 2, the direction in which the dividing position 100d extends is defined as the width direction WD, and the width of the laminate 100 in the width direction WD is shown as width W. The pressing member 211 preferably presses and fixes at least a part (for example, the adjacent part 100a) of the laminate 100 over the entire length (width W) of the dividing position 100d. However, as long as the laminate 100 can be divided, only a part of the width W may be pressed and fixed.

[0086] As shown in FIG. 2, it is preferable that the shoulder part 220a and the pressing part 220b are in contact with the metal foil 121 (laminate 100) over the entire width of the laminate 100. However, as long as the cutting process can be performed without problems, the pressing part 220b may contact the metal foil 121 (laminate 100) in a range narrower than the width W. In addition, when the metal foil 121 is larger than the power generation element 110, in order to perform shearing surely, the width of the shoulder part 220a is set to be equal to or larger than the width of the metal foil 121.

[0087] The laminate 100 is cut along the linear dividing position 100d. In the example shown in FIG. 1B, the lower mold 210 and the pressing member 211 are arranged such that their respective linear corner parts 210a and 211a are along the dividing position 100d. As shown in FIG. 1B, the end face 210s of the lower mold 210 and the end face 211s of the pressing member 211 may be flush. Alternatively, the end face 211s may be at a position on the lower mold 210 and away from the end face 210s.

[0088] Next, as shown in FIG. 1C, the power generation element 110 is cut along the dividing position 100d by applying a force to the portion away from the lower mold 210 (from another perspective, the portion away from the adjacent portion 100a) by the upper mold 220 (step (ii-a)). Specifically, the power generation element 110 is cut by moving the upper mold 220 in the direction of the arrow in FIG. 1C. Note that the position where the laminate 100 is fixed is not limited to the adjacent portion 100a, and a position away from the dividing position 100d may be fixed. Even in that case, by pressing the laminate 100 with the upper mold 220, stress concentrates on the portion (dividing position 100d) along the corner portion 210a of the laminate 100. As a result, the power generation element 110 can be cut along the dividing position 100d.

[0089] The pressing portion 220b protrudes more than the shoulder portion 220a. Therefore, when the pressing portion 220b comes into contact with the laminate 100, the shoulder portion 220a and the laminate 100 (metal foil 121) are not in contact. The position and the protruding amount of the pressing portion 220b can be selected so that the power generation element 110 is cut before the cutting of the metal foil 121 is completed.

[0090] The state of the laminate 100 and the like at the timing when the power generation element 110 is cracked is schematically shown in FIG. 3. In FIG. 3, the hatching of the laminate 100 is omitted. Since the power generation element 110 is highly brittle, it can be cracked at a minute angle. The angle α at which the power generation element 110 bends when the power generation element 110 is cracked is, for example, in the range of 0.5° to 5°.

[0091] The direction parallel to the surface of the laminate 100 disposed on the lower mold 210 and orthogonal to the splitting position 100d is defined as the direction PD. Also, the direction perpendicular to the surface of the laminate 100 disposed on the lower mold 210 is defined as the direction ND. The distance L1 (the distance in the direction PD) between the splitting position 100d and the portion pressed by the pressing portion 220b may be 0.3 mm or more, or may be 0.5 mm or more. The upper limit of the distance L1 may be equal to or less than the length of the laminate protruding from the lower mold 210, and may be 100 mm or less, or 80 mm or less. The interval L2 (the interval in the direction PD, not shown in the figure) between the end face 210s of the lower mold 210 and the shoulder 220a of the upper mold 220 when shearing the metal foil 121 should be an interval that can appropriately shear the metal foil 121, and it is preferably 5 μm or less (for example, 3 μm or less or 1 μm or less). There is no particular limitation on the lower limit of the interval L2, and it may be 0.1 μm or more or 0.5 μm or more.

[0092] When cutting the laminate 100 only by shearing, in order to prevent a short circuit of the power generation element 110, it is necessary to increase the interval L2 to a certain extent. However, when the interval L2 is increased, the metal foil 121 is not cleanly cut, and a short circuit due to poor cutting of the metal foil 121 is likely to occur. In this manufacturing method, while the power generation element 110 is divided by a dividing process, the metal foil 121 is divided by cutting. Therefore, even if the interval L2 is shortened to a certain extent (for example, 5 μm or less or 1 μm or less), the short circuit of the power generation element 110 does not increase as a result. As a result, a short circuit during cutting of the laminate 100 can be suppressed.

[0093] After the process of FIG. 1C, by further moving the upper mold 220 in the direction of the arrow, as shown in FIG. 1D, the metal foil 121 is cut at the splitting position 100d (process (ii-b)). Specifically, the metal foil 121 is sheared by the lower mold 210 and the shoulder 220a of the upper mold 220. Note that when the metal foil 121 is cut, the descent of the upper mold 220 may be promptly stopped. By restricting the descent of the upper mold 220, it is possible to suppress the end face of the power generation element 110 from being roughened by the upper mold 220. For example, when the metal foil 121 is disposed only on the side of the upper mold 220, after the metal foil 121 is cut, the descent of the upper mold 220 may be stopped before the shoulder 220a reaches the height of the upper surface of the lower mold 210.

[0094] In this way, the laminate 100 can be split. By repeatedly performing the process (ii) on the laminate 100 as necessary, a final laminate 100 having the final size can be obtained.

[0095] In the process (ii) (process (ii-a) and process (ii-b)), there is no particular limitation on the moving speed of the upper mold 220 in the direction ND, and it may be selected so that the process (ii) can be carried out. For example, the moving speed of the upper mold 220 in the direction ND may be in the range of 0.1 cm / s to 50 cm / s (for example, in the range of 1 cm / s to 30 cm / s).

[0096] The splitting process and the cutting process can be continuously executed by moving the upper mold 220 in the direction of the arrow. If the protruding amount of the pressing portion 220b is too small and the moving speed in the direction ND is high, the power generation element 110 may be sheared before the power generation element 110 cracks, and a short circuit may easily occur. Therefore, it is preferable to select the protruding amount of the pressing portion 220b and the moving speed in the direction ND within an appropriate range.

[0097] The splitting process and the cutting process are performed with a part of the laminate 100 fixed and a part not fixed. Specifically, the adjacent portion 100a adjacent to the splitting position 100d is fixed. On the other hand, the protruding portion 100b protruding outward from the adjacent portion 100a to the outside of the lower mold 210 is not fixed.

[0098] Next, if necessary, a current collector 122 is disposed on one side (the side where the metal foil 121 is not disposed) of the final laminate 100 obtained by the above steps, as shown in FIG. 1E. In this way, a power generation body 100X (all-solid-state battery) is obtained. The obtained power generation body 100X is housed in an exterior body if necessary. When the laminate 100 includes two metal foils 121 laminated on both sides of the power generation element 110, the final laminate 100 obtained by the above steps can be used as the power generation body as it is.

[0099] When the laminate 100 was cut 100 times by the method of Embodiment 1 above, no short circuit occurred in any of the cuts. On the other hand, when the laminate 100 was cut 100 times by a conventional shearing method using a conventional shearing device, a micro short circuit occurred between the positive electrode layer 111 and the negative electrode layer 112 in most of the cuts.

[0100] An example of a manufacturing apparatus 200 including a lower mold 210, a pressing member 211, and an upper mold 220 is shown in FIG. 4. The manufacturing apparatus of FIG. 4 includes a lower mold 210, a pressing member 211, an upper mold 220, drive mechanisms 231 and 232, and a roller 240 (feeding mechanism). The drive mechanism 231 moves the upper mold 220 down and up along the direction of the arrow in FIG. 1C. The drive mechanism 232 fixes and releases the laminate 100 by moving the pressing member 211. The roller 240 feeds the laminate 100 and moves it to an appropriate position.

[0101] As described above, the manufacturing apparatus 200 executes step (ii). As long as step (ii) can be executed, the moving direction of the upper mold 220 is not limited. For example, as shown in FIG. 5, the drive mechanism may rotate the upper mold 220 about a rotation axis at the rotation center 220c. The dotted line indicates the contour of the upper mold 220 before rotation. The rotation axis is located at a position away from the division position 100d and extends in a direction parallel to the direction in which the division position 100d extends (the direction perpendicular to the plane of FIG. 5). Even when the upper mold 220 is rotated, step (ii) can be executed in the same manner as when the upper mold 220 is linearly moved. Note that the position of the rotation center 220c is not particularly limited and may not be the position shown in FIG. 5. The upper mold 220 shown in FIG. 5 has a shape different from the upper mold 220 described above. In the upper mold 220 shown in FIG. 5, of the two corners of the protruding portion on the lower surface of the upper mold 220, one corner becomes the shoulder portion 220a and the other corner becomes the pressing portion 220b.

[0102] The upper mold 220 is not limited to the examples shown in FIGS. 4 and 5, and any upper mold 220 that can execute step (ii) may be used. Another example of the shape of the upper mold 220 is shown in FIG. 6. In the upper mold 220 of FIG. 6, the pressing portion 220b is formed by the inclination of the surface 220s of the upper mold 220 that faces the laminate 100.

[0103] In an example of the manufacturing method (M2), step (II) can be carried out in the same manner as step (ii-a) of Embodiment 1, except that the laminate 100 is replaced with the power generation element 110. In this case, the upper mold 220 may not include the shoulder portion 220a for cutting the metal foil 121.

[0104] Another example of the manufacturing method (M2) is schematically shown in FIG. 7. In the example of FIG. 7, a member 310 for concentrating stress along the splitting position 100d and a member 320 for pressing both ends of the power generation element 110 (laminated body) are used. The member 310 includes a convex portion that linearly contacts the power generation element 110 along the splitting position 100d. With the convex portion in contact with the power generation element 110 along the splitting position 100d, by pressing the portion of the power generation element 110 away from the splitting position 100d in the direction of the arrow by the member 320, the power generation element 110 can be split along the splitting position 100d.

[0105] In the above description, only the example of splitting only one side of the laminated body at a time has been described. However, it is also possible to split a plurality of sides of the laminated body by a single movement of the second type. For example, two of the above-described second types are arranged such that their shoulders form an L shape. Similarly, the first type and the pressing member are also arranged to correspond to the second type. At this time, the two second types are arranged such that their positions in the direction ND are different (that is, they are arranged at different heights). By using these second types, the first type, and the pressing member, it is also possible to split two sides of the laminated body by a single movement of the second type. In a similar manner, it is also possible to split three or four sides of the laminated body by a single movement of the second type. Note that as long as the sides do not intersect each other, it is possible to split them simultaneously without making their positions in the direction ND different.

Industrial Applicability

[0106] The present disclosure can be used for a solid battery, a method for manufacturing a solid battery, and a manufacturing apparatus for a solid battery.

Explanation of Reference Numerals

[0107] 100: Laminated body 100a: Adjacent portion 100d: Splitting position 110: Power generation element 111: Positive electrode layer 112: Negative electrode layer 113: Solid electrolyte layer 121: Metal foil 200: Manufacturing device 210: Lower mold (first mold) 211: Pressing member 220: Upper mold (second mold) 220a: Shoulder part 220b: Pushing part

Claims

1. Step (i) of preparing a laminate including a power generation element including a positive electrode layer, a negative electrode layer, and a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer, and at least one metal foil disposed on at least one main surface of the power generation element; Step (ii) of dividing the power generation element at a linear division position and cutting the at least one metal foil at the division position, in this order, a method for manufacturing a solid battery.

2. The step (ii) Step (ii-a) of dividing the power generation element at the division position; And step (ii-b) of cutting the at least one metal foil at the division position, the manufacturing method according to claim 1.

3. The manufacturing method according to claim 2, wherein step (ii-a) is completed before step (ii-b) is completed.

4. In the step (ii), the power generation element is divided at the division position by applying a force to a portion of the laminate on the side opposite to the fixed portion across the division position while fixing a part of the laminate. The manufacturing method according to any one of claims 1 to 3.

5. In the step (ii), the laminate on the side where the force is applied is performed in an unfixed state with respect to the fixed part, the manufacturing method according to claim 4.

6. In the step (ii), the at least one metal foil is cut by shearing, the manufacturing method according to any one of claims 1 to 5.

7. The step (ii) is performed using the first mold and the second mold with the laminate disposed on the first mold, The power generation element is divided at the division position by pressing a portion of the laminate away from the first mold with the second mold, The manufacturing method according to any one of claims 1 to 3, wherein the at least one metal foil is cut at the dividing position by the first type and the second type.

8. Step (ii) is performed using the first type, the second type, and a pressing member. In step (ii), with a part of the laminate fixed by the first type and the pressing member, the part of the laminate away from the first type is pushed by the second type to divide the power generation element at the dividing position. The manufacturing method according to claim 7.

9. The manufacturing method according to claim 8, wherein step (ii) is performed on the laminate on the side of the part pushed by the second type rather than the fixed part in an unfixed state.

10. The second type includes a shoulder portion for cutting the at least one metal foil and a pressing portion for pressing the laminate. By pushing the part of the laminate away from the first type with the pressing portion, the power generation element is divided at the dividing position. The manufacturing method according to any one of claims 7 to 9, wherein the at least one metal foil is sheared at the dividing position by the first type and the shoulder portion.

11. The manufacturing method according to any one of claims 7 to 10, wherein step (ii) is performed by rotating the second type.

12. In step (i), after laminating the materials of the positive electrode layer, the solid electrolyte layer, and the negative electrode layer and the at least one metal foil, the laminated materials and the at least one metal foil are pressed together to prepare the laminate. The manufacturing method according to any one of claims 1 to 11.

13. A manufacturing apparatus for a solid battery, The solid-state battery includes a laminate including a power generation element including a positive electrode layer, a negative electrode layer, and a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer, and at least one metal foil disposed on at least one main surface of the power generation element. A manufacturing apparatus including a dividing mechanism that divides the power generation element at a linear dividing position and a cutting mechanism that cuts the at least one metal foil at the dividing position.

14. The manufacturing apparatus according to claim 13, including a first type and a second type that function as the dividing mechanism and the cutting mechanism.

15. The manufacturing apparatus according to claim 14, wherein the second type includes a pressing portion that functions as the dividing mechanism by pressing a portion of the laminate away from the first type, and a shoulder portion that functions as the cutting mechanism.

16. The manufacturing apparatus according to claim 14 or 15, further including a pressing member for fixing the laminate to the first type.

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