Peeling mechanism and peeling method

Abstract

The present invention provides a peeling mechanism and peeling method that can improve the accuracy of peeling a substrate from a solid electrolyte layer. The peeling mechanism (132) for peeling a substrate sheet (123) from a first solid electrolyte layer (SE1) transferred to a positive electrode side sheet (200) includes: a peeling roller (130) that peels the substrate sheet (123) from the first solid electrolyte layer (SE1); and a substrate roll (131) that takes up the substrate sheet (123) peeled by the peeling roller (130), the peeling roller (130) peeling the substrate sheet (123) in a direction opposite to the transport direction of the positive electrode side sheet (200).

Description

Technical Field

[0001] This invention relates to a stripping mechanism and a stripping method. Background Technology

[0002] In recent years, research and development related to secondary batteries that help improve energy efficiency have been carried out in order to ensure that more people have access to affordable, reliable and sustainable modern energy.

[0003] Previously, as a method for manufacturing solid-state batteries, there is a known method of manufacturing them by pressing the positive electrode layer, the solid electrolyte layer and the negative electrode layer with rollers (for example, Patent Document 1).

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2023-085663 Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] In the transfer of the solid electrolyte layer to the positive electrode layer, after the solid electrolyte layer disposed on the substrate is transferred to the positive electrode layer by rolling, the substrate is peeled off from the solid electrolyte layer, but the peeling accuracy of the substrate may be reduced.

[0009] This invention provides a peeling mechanism and peeling method that can improve the accuracy of peeling a substrate from a solid electrolyte layer. This, in turn, helps to improve energy efficiency.

[0010] Methods for solving problems

[0011] One aspect of the present invention provides a peeling mechanism that peels a substrate from a transfer body transferred to a base material sheet, wherein,

[0012] The stripping mechanism includes:

[0013] A peeling roller that peels the substrate from the transfer body; and

[0014] A substrate roll, which takes up the substrate after it has been peeled off by the peeling roller.

[0015] The peeling roller peels the substrate in a direction opposite to the transport direction of the parent material sheet.

[0016] Furthermore, another aspect of the present invention provides a peeling method for peeling a substrate from a transfer body transferred to a base material sheet, wherein...

[0017] The stripping method comprises:

[0018] The identification step for identifying the peeling start point of the substrate;

[0019] The peeling start point is controlled to a predetermined position by a peeling start point control step; and

[0020] The peeling step involves peeling the substrate in a direction opposite to the transport direction of the parent material sheet, based on the peeling start point controlled to the specified position.

[0021] Invention Effects

[0022] According to the present invention, the precision of peeling the substrate sheet from the solid electrolyte layer can be improved. This, in turn, can help improve energy efficiency. Attached Figure Description

[0023] Figure 1 This is a cross-sectional view representing an example of a solid-state battery 1.

[0024] Figure 2 This is a diagram showing an example of a pressing apparatus 100 for manufacturing a solid-state battery 1.

[0025] Figure 3 This is a diagram showing a portion of the pressing apparatus 100, and in particular an example illustrating the structure of peeling off the substrate sheet 123 after transferring the first solid electrolyte layer SE1.

[0026] Figure 4 This is a diagram illustrating an example of the stripping mechanism 132.

[0027] Figure 5 This is a diagram showing a portion of the pressing device 100, and in particular an example of the transfer of the intermediate layer transfer roller 150 and the negative electrode side transfer roller 160.

[0028] Figure 6 This is a flowchart illustrating an example of a pressing method using a pressing device 100 that includes a stripping method.

[0029] Figure 7 This is a diagram used to illustrate other examples of the stripping mechanism 132.

[0030] Figure 8 This is a diagram showing a comparative example of the stripping mechanism 132a.

[0031] Explanation of reference numerals in the attached figures:

[0032] 123 Substrate sheet (substrate)

[0033] 130 peeling roller

[0034] 131 Substrate Roll

[0035] 132 Stripping Mechanism

[0036] 200 Positive electrode side sheet (base sheet)

[0037] 300 Identification Department

[0038] 400 Control Department

[0039] P stripping start point

[0040] SE1 First Solid Electrolyte Layer (Transfer Body)

[0041] S30 Identification Steps

[0042] S31 Peeling Start Control Steps

[0043] S32 Peeling step. Detailed Implementation

[0044] Hereinafter, an embodiment will be described with reference to the accompanying drawings. The peeling mechanism 132 in the embodiment is part of a pressing apparatus 100 for manufacturing a solid-state battery 1. Furthermore, the peeling method is part of a pressing method using the pressing apparatus 100. In the following description, the solid-state battery 1, the pressing apparatus 100 including the peeling mechanism 132, and the pressing method including the peeling method will be described sequentially.

[0045] Solid-state batteries

[0046] Figure 1 This is a schematic diagram illustrating an example of a solid-state battery 1. The solid-state battery 1 is an all-solid-state battery having an electrode 10 having a negative electrode layer 2, a solid electrolyte layer 3, and a positive electrode layer 4 stacked on top of each other. In an embodiment, as... Figure 1 As shown, the stacked structure of the solid-state battery 1 is described using a sequence of layers: negative electrode layer 2, solid electrolyte layer 3, positive electrode layer 4, solid electrolyte layer 3, and negative electrode layer 2. However, the structure of the solid-state battery 1 is not limited to the above description. For example, the solid-state battery 1 can be constructed in other ways besides... Figure 1 In addition to the electrode 10 shown, it may also have an outer casing or other structures that can be used in solid-state batteries.

[0047] The solid electrolyte layer 3 in the solid-state battery 1 has at least a first solid electrolyte layer SE1 disposed on the positive electrode layer 4 side and a negative electrode side solid electrolyte layer SE3 disposed on the negative electrode layer 2 side. The solid electrolyte layer 3 may also have a second solid electrolyte layer SE2 disposed adjacent to the first solid electrolyte layer SE1. In this embodiment, the case where the solid electrolyte layer 3 is composed of the above three layers will be described. An intermediate layer 5 may also be arbitrarily disposed between the negative electrode layer 2 and the solid electrolyte layer 3.

[0048] There are no particular limitations on the solid-state battery 1; it can be a lithium-ion solid-state rechargeable battery or a lithium metal rechargeable battery.

[0049] (Negative electrode layer)

[0050] The negative electrode layer 2 has a negative electrode active material layer 21 and a negative electrode current collector layer 22. The negative electrode active material layer 21 is not particularly limited and can be composed of a material that can be used as a negative electrode active material in the solid-state battery 1. Examples of negative electrode active materials constituting the negative electrode active material layer 21 include: lithium metal, lithium alloys, silicon-based active materials such as Si and Si alloys, and lithium titanate (Li4Ti5O4). 12 Lithium transition metal oxides such as TiO2, Nb2O3 and WO3, metal sulfides, metal nitrides, carbon materials such as graphite, soft carbon and hard carbon, and metal indium.

[0051] The negative electrode active material layer 21 may also include materials other than those described above that can be contained in the negative electrode active material layer 21 of the solid-state battery 1. These materials include, for example, solid electrolytes, conductive additives, and binders. The solid electrolyte includes the same solid electrolyte contained in the solid electrolyte layer 3 described later. Conductive additives include carbon black, natural graphite, carbon fibers, carbon nanotubes, etc. Binders include nitrile polymers, polyester polymers, acrylic polymers, cellulose polymers, styrene polymers, styrene-butadiene polymers, vinyl acetate polymers, polyurethane polymers, and vinyl fluoride polymers, etc.

[0052] The negative electrode current collector layer 22 is not particularly limited and can be made of copper, nickel, or stainless steel. The shape of the negative electrode current collector layer 22 can be, for example, foil, plate, mesh, non-woven fabric, or foam. In this embodiment, the negative electrode current collector layer 22 is composed of a negative electrode current collector foil 22a.

[0053] (Solid electrolyte layer)

[0054] A solid electrolyte layer 3 is formed between the negative electrode layer 2 and the positive electrode layer 4. In an embodiment, the solid electrolyte layer 3 has a structure in which a first solid electrolyte layer SE1, a second solid electrolyte layer SE2, and a negative electrode side solid electrolyte layer SE3 disposed on the negative electrode side are stacked sequentially.

[0055] The first solid electrolyte layer SE1 is disposed in contact with the positive electrode active material layer 41 in the positive electrode layer 4. The solid electrolyte constituting the first solid electrolyte layer SE1 is not particularly limited, as long as it is a material suitable for use as an electrolyte in a solid-state battery. Examples include sulfide solid electrolytes, oxide solid electrolytes, halide solid electrolytes, inorganic solid electrolytes containing lithium salts, and polymer-based solid electrolytes such as polyethylene oxide. One or more of the above-mentioned solid electrolytes may be used.

[0056] Furthermore, the first solid electrolyte layer SE1 contains a binder in addition to the solid electrolyte material. The same binder that can be used in the negative electrode active material layer 21 can be used as the binder. The mass content of the binder in the first solid electrolyte layer SE1 relative to the total mass of the first solid electrolyte layer SE1 is greater than the mass content of the binder in the second solid electrolyte layer SE2 relative to the total mass of the second solid electrolyte layer SE2. The upper limit of the binder content in the first solid electrolyte layer SE1 is, for example, 25% by mass. The binder content in the first solid electrolyte layer SE1 is preferably 10 to 30% by mass. Therefore, during the pressing of the positive electrode layer 4, the first solid electrolyte layer SE1 easily extends along with the positive electrode layer 4.

[0057] In addition, the first solid electrolyte layer SE1 may contain materials suitable for solid-state batteries, in addition to solid electrolyte materials and binders.

[0058] Furthermore, the thickness of the first solid electrolyte layer SE1 (the length of each layer in the stacking direction) is preferably thinner than the thickness of the second solid electrolyte layer SE2. The thickness of the first solid electrolyte layer SE1 is preferably, for example, 3 to 15 μm.

[0059] The second solid electrolyte layer SE2 is an arbitrarily configured layer, disposed adjacent to the first solid electrolyte layer SE1. The solid electrolyte material constituting the second solid electrolyte layer SE2 is not particularly limited and can be the same material as the solid electrolyte material constituting the first solid electrolyte layer SE1. Similar to the first solid electrolyte layer SE1, the second solid electrolyte layer SE2 may contain, in addition to the solid electrolyte material, a binder, etc. The content of the binder in the second solid electrolyte layer SE2 is less than or equal to the content of the binder in the first solid electrolyte layer SE1. The binder content in the second solid electrolyte layer SE2 is preferably, for example, 10 to 30% by mass. This improves the energy density of the solid-state battery 1. The second solid electrolyte layer SE2 may also include a support. The support can be a three-dimensional structure such as a mesh, woven fabric, non-woven fabric, embossed body, perforated body, stretched body, or foam. The second solid electrolyte layer SE2 may also not include the aforementioned support.

[0060] The thickness (length of each layer in the stacking direction) of the second solid electrolyte layer SE2 is preferably greater than the thickness of the first solid electrolyte layer SE1. Furthermore, the thickness of the second solid electrolyte layer SE2 is preferably greater than the thickness of the negative electrode side solid electrolyte layer SE3, as described later. The thickness of the second solid electrolyte layer SE2 is preferably, for example, 10 to 50 μm.

[0061] A solid electrolyte layer SE3 is disposed on the negative electrode side. The solid electrolyte layer SE3 is disposed adjacent to the negative electrode layer 2. For example... Figure 1As shown, when the solid-state battery 1 has an intermediate layer 5, the negative electrode side solid electrolyte layer SE3 can also be configured adjacent to the intermediate layer 5.

[0062] The solid electrolyte material constituting the negative electrode side solid electrolyte layer SE3 is not particularly limited and can be the same material as the solid electrolyte material constituting the first solid electrolyte layer SE1. The content of the binder in the negative electrode side solid electrolyte layer SE3 is preferably, for example, 1.3 to 8.7% by mass. In volume percentage, the content of the binder in the negative electrode side solid electrolyte layer SE3 is preferably, for example, 2.7% by volume or more and 10% by volume or less. The content of the binder in the negative electrode side solid electrolyte layer SE3 is less than the content of the binder in the first solid electrolyte layer SE1.

[0063] The thickness (length of each layer in the stacking direction) of the negative electrode side solid electrolyte layer SE3 is preferably thinner than the thickness of the second solid electrolyte layer SE2. The thickness of the negative electrode side solid electrolyte layer SE3 is preferably, for example, 3 to 8.5 μm.

[0064] (Positive electrode layer)

[0065] The positive electrode layer 4 has a positive electrode active material layer 41 and a positive electrode current collector layer 42. In one embodiment, the positive electrode layer 4 has a structure in which two positive electrode active material layers 41 are stacked on both sides of a positive electrode current collector layer 42. Alternatively, the structure of the positive electrode layer 4 is not limited to the above description, and it may also have a structure in which one positive electrode active material layer 41 is stacked on one side of a positive electrode current collector layer 42.

[0066] The positive electrode active material layer 41 is not particularly limited and can be composed of a material suitable for use as a positive electrode active material in solid-state batteries. Examples of positive electrode active materials constituting the positive electrode active material layer 41 include: LiCoO2, LiNiO2, LiCo... x Ni y Mn z Layered positive electrode active material particles such as O2 (x+y+z=1), LiVO2, and LiCrO2, and LiMn2O4 and Li(Ni) 0.25 Mn 0.75 Spinel-type positive electrode active materials such as Li₂O₄, LiCoMnO₄, and Li₂NiMn₃O₈; olivine-type positive electrode active materials such as LiCoPO₄, LiMnPO₄, and LiFePO₄; solid solution oxides (Li₂MnO₃-LiMO₂ (M=Co, Ni, etc.)); conductive polymers such as polyaniline and polypyrrole; sulfides such as Li₂S, CuS, Li-Cu-S compounds, TiS₂, FeS, MoS₂, and Li-Mo-S compounds; and mixtures of sulfur and carbon, etc. The positive electrode active materials can be one of the above materials or composed of two or more of the above materials.

[0067] The positive electrode active material layer 41 may include a binder, etc. The binder content of the positive electrode active material layer 41 is preferably 0.5 to 5% by mass, and more preferably 2.56% by mass. The thickness of the positive electrode active material layer 41 (the length of each layer in the stacking direction) is preferably, for example, 80 to 100 μm. This improves the battery capacity of the solid-state battery 1.

[0068] The positive current collector layer 42 is not particularly limited, and can be made of materials such as aluminum, stainless steel, or conductive carbon (e.g., graphite, carbon nanotubes). The shape of the positive current collector layer 42 can be, for example, foil, plate, mesh, non-woven fabric, or foam. In this embodiment, the positive current collector layer 42 is composed of a positive current collector foil 42a.

[0069] (Intermediate layer)

[0070] An intermediate layer 5 is disposed between the negative electrode layer 2 and the solid electrolyte layer 3. For example, in the case where the solid-state battery 1 is a lithium metal battery, the intermediate layer 5 has the function of uniformly depositing lithium metal. Therefore, the interface between the intermediate layer 5 and the solid electrolyte layer 3 is stabilized. When the solid-state battery 1 is a lithium metal secondary battery with an intermediate layer 5, the solid-state battery 1 can also be a negative electrode-free battery where the negative electrode active material layer 21 is absent during the initial charge. In this case, after the initial charge and discharge, a lithium metal layer serving as the negative electrode active material layer 21 is formed.

[0071] The materials constituting the intermediate layer 5 are not particularly limited, and may include metals capable of forming alloys with lithium, amorphous carbon, etc. Metals capable of forming alloys with lithium include, for example, tin (Sn), silicon (Si), zinc (Zn), magnesium (Mg), gold (Au), platinum (Pt), palladium (Pd), silver (Ag), aluminum (Al), bismuth (Bi), antimony (Sb), etc. Metals capable of forming alloys with lithium can be nanoparticles. Amorphous carbon includes, for example, carbon blacks such as acetylene black, furnace black, and Ketjen black, coke, activated carbon, etc. Amorphous carbon can be easily graphitized carbon (soft carbon), or difficult-to-graphitize carbon (hard carbon), CNTs (carbon nanotubes), fullerenes, and graphene. In addition to the above materials, the intermediate layer may also contain a binder.

[0072] [Suppression device]

[0073] Next, the structure of the pressing apparatus 100 for manufacturing the solid-state battery 1 configured as described above will be explained. Figure 2 This illustrates an example of the pressing device 100 in the embodiment. The pressing device 100 includes a first positive electrode side transfer roller 120 and a peeling roller 130 (see reference). Figure 3 ), second positive electrode side transfer roller 140, intermediate layer transfer roller 150 (refer to) Figure 5 ), negative electrode side transfer roller 160 (refer to) Figure 5The negative electrode side sheet lamination roller 170, the positive electrode pressing roller 180, and the integrated pressing roller 190 are the main components. In addition, the peeling roller 130 is a component of the peeling mechanism 132 described later. The pressing device 100 feeds the positive electrode side sheet 200 in one direction through the above-mentioned rollers and continuously manufactures the solid-state battery 1.

[0074] In addition, Figure 2 In this context, the direction in which the positive electrode side sheet 200 is delivered is defined as the "transport direction," and the direction orthogonal to this transport direction is defined as the "width direction." Furthermore, in... Figure 1 The diagram shows the range of pressing or transfer pressing performed in the positive electrode pressing step S4, the second solid electrolyte layer transfer step S5, the intermediate layer transfer step S6, the negative electrode side solid electrolyte layer transfer step S7, and the integrated pressing step S9, which are described later.

[0075] The positive electrode side sheet 200 is an example of a "master sheet", which is a sheet-like component obtained by laminating a positive electrode active material layer 41 on a positive electrode current collector foil 42a constituting the positive electrode current collector layer 42. The positive electrode side sheet 200 is fed out by rollers (not shown) and is transported in a manner that extends continuously from the base end side to the terminal in the production line of the solid-state battery 1.

[0076] The first positive electrode side transfer roller 120, the peeling roller 130, the second positive electrode side transfer roller 140, the intermediate layer transfer roller 150, the negative electrode side transfer roller 160, and the negative electrode side sheet lamination roller 170 are each composed of a pair of rotating bodies having a specified length in the width direction.

[0077] These rotating bodies are arranged from the upstream side along the transport direction of the positive electrode side sheet 200 in the following order: first positive electrode side transfer roller 120, peeling roller 130, positive electrode pressing roller 180, second positive electrode side transfer roller 140, negative electrode side sheet stacking roller 170, and integrated pressing roller 190.

[0078] The intermediate layer transfer roller 150 and the negative electrode side transfer roller 160 are configured away from the transport line (hereinafter referred to as the "transport line") that transports the positive electrode side sheet 200 in the transport direction, to perform the transfer pressing of the intermediate layer 5 or the negative electrode side solid electrolyte layer SE3. Then, as described later, the intermediate layer 5 and the negative electrode layer 2, on which the negative electrode side solid electrolyte layer SE3 has been transferred, are transported to the upper or lower surface side of the positive electrode side sheet 200, merge with the transport line of the positive electrode side sheet 200, and are stacked by the negative electrode side sheet stacking roller 170.

[0079] Regarding the first positive electrode side transfer roller 120, the second positive electrode side transfer roller 140, the intermediate layer transfer roller 150, and the negative electrode side transfer roller 160, the transfer pressing is performed by sandwiching the substrate or other sheet on the side to be transferred and the sheet with the solid electrolyte layer to be transferred between a pair of rollers and pressing them through.

[0080] Figure 3 A more detailed representation is shown. Figure 2 An enlarged view of the portion enclosed by the dashed line. As shown here, the first positive electrode side transfer roller 120 clamps the transfer sheet 121, which is wound from the transfer sheet roll 122 with the transfer sheet 121 wound on it, between a pair of rollers and applies pressure. This allows the first solid electrolyte layer SE1 disposed on the transfer sheet 121 to be transferred to the positive electrode side sheet 200. The first solid electrolyte layer SE1 is an example of a "transfer body".

[0081] In addition, such as Figure 3 As shown, the transfer sheet 121 has a first solid electrolyte layer SE1 and a substrate sheet 123 on which the first solid electrolyte layer SE1 is disposed. The substrate sheet 123 is peeled off from the first solid electrolyte layer SE1 being transferred by a peeling mechanism 132, and is made of, for example, PET (polyethylene terephthalate).

[0082] Here, the peeling mechanism 132 in the embodiment will be described. The peeling mechanism 132 includes: the peeling roller 130 described above, which peels the substrate sheet 123 from the first solid electrolyte layer SE1 transferred to the positive electrode side sheet 200; and a substrate roll 131, which winds up the substrate sheet 123 peeled off by the peeling roller 130. Figure 3 As shown, the peeling mechanism 132 is located downstream of the first positive electrode side transfer roller 120, and peels off the substrate sheet 123 from the first solid electrolyte layer SE1 that has been transferred. Figure 3 In the diagram, the first solid electrolyte layer SE1 in the transfer sheet 121 rolled out from the transfer sheet roll 122 is represented by a solid line, and the peeled-off substrate sheet 123 is represented by a dashed line. Additionally, in... Figure 3 The arrows shown at each roller and each roll indicate the rotation direction of each roller and each roll.

[0083] As described above, the substrate sheet 123 is peeled off from the first solid electrolyte layer SE1 transferred to the positive electrode side sheet 200 by the peeling roller 130, but the peelability of the substrate sheet 123 may vary depending on the direction of peeling off the substrate sheet 123 (hereinafter referred to as the "peeling direction"). For example, as Figure 8As shown in the comparative example, when the transport direction of the positive electrode side sheet 200a, on which the first solid electrolyte layer SE1a is transferred, is set to 0° and the peeling direction of the substrate sheet 123a is 90° or less, the substrate sheet 123a is pulled up by the peeling roller 130 in a direction below 90°. In this case, the peeling direction of the substrate sheet 123a and the transport direction of the positive electrode side sheet 200a are the same, and it is impossible to generate appropriate shear force between the first solid electrolyte layer SE1a and the substrate sheet 123a, which may reduce the peelability of the substrate sheet 123a. For example, the positive electrode side sheet 200a may bend, or the positive electrode side sheet 200a may break starting from this bend. Therefore, in Figure 3 In the illustrated embodiment, an appropriate shear force is generated between the first solid electrolyte layer SE1 and the substrate sheet 123 to improve the peelability of the substrate sheet 123. Furthermore, the phrase "the peeling direction and the transport direction are the same" refers to peeling the substrate sheet 123 at an angle ranging from 0° to 90° or less. Additionally, in Figure 8 In the comparative examples, to distinguish them from the same constituent elements in the embodiments, reference numerals marked "a" are appended after the numbers.

[0084] In this embodiment, the peeling roller 130 is configured to peel the substrate sheet 123 in a direction opposite to the transport direction of the positive electrode side sheet 200. Here, "peeling in a direction opposite to the transport direction" means peeling the substrate sheet 123 at an angle greater than 90° and less than 180° when the transport direction is set to 0°. As an example of implementing such a structure, the peeling roller 130 is positioned upstream of the starting point P for peeling the substrate sheet 123 from the first solid electrolyte layer SE1 being transferred, in the transport direction of the positive electrode side sheet 200. By positioning the peeling roller 130 upstream of the peeling starting point P, the substrate sheet 123 is peeled in a direction opposite to the transport direction, starting from the peeling starting point P; in other words, the substrate sheet 123 is pulled in a direction opposing the transport direction. Thus, as described above… Figure 8 Compared to the case where the transport direction and the peeling direction are the same as in the comparative example, the peelability of the substrate sheet 123 can be improved.

[0085] Furthermore, in the embodiment, as described above, when the transport direction is set to 0°, the peel angle α of the substrate sheet 123 is an angle greater than 90° and less than 180°. However, in order to improve the peelability of the substrate sheet 123, it is preferable to peel the substrate sheet 123 at a peel angle that is closer to a parallel angle relative to the opposite direction of the transport direction. Therefore, the peel angle α of the substrate sheet 123 is more preferably an angle close to 180°.

[0086] In this way, by peeling the substrate sheet 123 in a direction opposite to the transport direction of the positive electrode sheet 200 and pulling the substrate sheet 123 in a direction opposing the transport direction, an appropriate shear force can be generated between the first solid electrolyte layer SE1 and the substrate sheet 123, thus suppressing bending of the positive electrode sheet 200 or breakage originating from such bending. As a result, the peelability when peeling the substrate sheet 123 from the first solid electrolyte layer SE1 can be improved.

[0087] On the other hand, as described above, since the positive electrode sheet 200 moves at a predetermined speed in the transport direction, the peeling start point P may sometimes deviate from the predetermined position when the speed at which the substrate roll 131 winds the substrate sheet 123 is inconsistent with the transport speed of the positive electrode sheet 200. Furthermore, theoretically, when the winding speed of the substrate sheet 123 is consistent with the transport speed of the positive electrode sheet 200, the peeling start point P should not deviate from the predetermined position. However, in reality, even when the winding speed of the substrate sheet 123 is consistent with the transport speed of the positive electrode sheet 200, the peeling start point P may still deviate from the predetermined position. Here, "predetermined position" refers to the ideal position of the peeling start point P, such as a position where the substrate sheet 123 can be stably peeled. In the embodiment, in order to stably peel the substrate sheet 123, the peeling start point P is always identified and controlled at the predetermined position.

[0088] Specifically, such as Figure 4 As shown, the peeling mechanism 132 also includes an identification unit 300 for identifying the peeling start point P and a control unit 400 for controlling the peeling start point P identified by the identification unit 300 to be positioned at a predetermined location. The identification unit 300 may be a camera or the like capable of identifying the peeling start point P. The information identified by the identification unit 300 is output to the control unit 400. The control unit 400 may be, for example, a known computer that includes a control unit that performs various calculations, a storage unit with a storage medium, and an input / output interface (not shown) for inputting and outputting data to and from the inside and outside of the control unit 400. Furthermore, in Figure 4 In the example shown, only the upper side of the structure of the peeling mechanism 132 and the transfer sheet 121 relative to the positive electrode side sheet 200 is shown, and the structure of the lower side is omitted.

[0089] The control unit 400 controls the position of the peeling start point P at a predetermined position by controlling the rotation speed of the substrate roll 131. More specifically, the control unit 400 increases the rotation speed of the substrate roll 131, for example, when the peeling start point P is located downstream of the predetermined position. In other words, when the peeling start point P is located downstream of the predetermined position, the rotation speed of the substrate roll 131 is relatively slow relative to the transport speed of the positive electrode sheet 200, so the control unit 400 controls the peeling start point P at the predetermined position by increasing the rotation speed of the substrate roll 131. Conversely, the control unit 400 decreases the rotation speed of the substrate roll 131 when the peeling start point P is located upstream of the predetermined position. In other words, when the peeling start point P is located upstream of the predetermined position, the rotation speed of the substrate roll 131 is relatively fast relative to the transport speed of the positive electrode sheet 200, so the control unit 400 controls the peeling start point P at the predetermined position by decreasing the rotation speed of the substrate roll 131.

[0090] Furthermore, in the width direction of the positive electrode side sheet 200, it is preferable to control the starting point, i.e., the peeling starting point P, where the substrate sheet 123 is peeled off from the first solid electrolyte layer SE1. For example, it is preferable to pre-configure the peeling roller 130 so that one side is inclined relative to the other side in the width direction. Thus, it is conceivable that the substrate sheet 123 is peeled off from the first solid electrolyte layer SE1 while tilting from one side to the other in the width direction. In this case, the peeling starting point line connecting the peeling starting point P in the width direction is configured to be inclined relative to that width direction.

[0091] Therefore, in addition to controlling the position of the peeling start point P, the peeling start line can also be controlled, thus improving the peeling accuracy of the substrate sheet 123 compared to the case where the peeling roller 130 is not tilted relative to the width direction.

[0092] In addition, such as Figure 3 As shown, the transfer sheet 121 is symmetrically disposed on both sides of the positive electrode side sheet 200, sandwiching it between the two sides, and is configured to transfer the first solid electrolyte layer SE1 onto both sides of the positive electrode side sheet 200. Thus, the first solid electrolyte layer SE1 can be transferred onto both sides of the positive electrode side sheet 200 simultaneously.

[0093] like Figure 2 As shown, the second positive electrode side transfer roller 140 transfers the second solid electrolyte layer SE2 onto the positive electrode side sheet 200, which has been transferred and pressed with the first solid electrolyte layer SE1.

[0094] like Figure 5 As shown, the intermediate layer transfer roller 150 transfers the intermediate layer 5 onto the negative electrode active material layer 21 stacked on the negative electrode current collector foil 22a. Thus, the intermediate layer 5 is disposed between the negative electrode active material layer 21 and the negative electrode side solid electrolyte layer SE3.

[0095] like Figure 5 As shown, the negative electrode side transfer roller 160 transfers the negative electrode side solid electrolyte layer SE3 onto the intermediate layer 5 to form the negative electrode side sheet 210.

[0096] like Figure 2 As shown, the negative electrode side sheet stacking roller 170 transports and stacks the negative electrode side sheet 210, which has a negative electrode side solid electrolyte layer SE3, onto the positive electrode side sheet 200, which has a first solid electrolyte layer SE1 and a second solid electrolyte layer SE2 transferred thereon.

[0097] like Figure 2 As shown, the positive electrode pressing roller 180 and the integrated pressing roller 190, like each transfer roller, are each composed of a pair of rotating rollers. According to each processing step, the positive electrode side sheet 200, which is laminated with a solid electrolyte layer, etc., is sandwiched between the pair of rollers, pressed, and passed through to achieve high density. The positive electrode pressing roller 180 presses the positive electrode side sheet 200, on which the first solid electrolyte layer SE1 has been transferred. The integrated pressing roller 190 presses the positive electrode side sheet 200 and the negative electrode side sheet 210 in a laminated state, thus integrating the electrode 10. Therefore, while integrating the positive electrode side sheet 200 and the negative electrode side sheet 210, the first solid electrolyte layer SE1, the second solid electrolyte layer SE2, and the negative electrode side solid electrolyte layer SE3 are also increased in density.

[0098] [Suppression Method]

[0099] Next, the pressing method of the pressing device 100 configured as described above will be explained. Figure 6 This is a flowchart illustrating an example of the pressing method. The pressing method includes the following processing steps: positive electrode side sheet conveying step S1, first solid electrolyte layer transfer step S2, substrate sheet peeling step S3, positive electrode pressing step S4, second solid electrolyte layer transfer step S5, intermediate layer transfer step S6, negative electrode side solid electrolyte layer transfer step S7, negative electrode side sheet stacking step S8, and integrated pressing step S9.

[0100] The positive electrode side sheet conveying step S1 is a step in which the positive electrode side sheet 200 is conveyed and sent out by a conveying roller (not shown). That is, a positive electrode active material is coated on the positive electrode current collector foil 42a constituting the positive electrode current collector layer 42 and the stacked positive electrode side sheet 200 is sent out.

[0101] The first solid electrolyte layer transfer step S2 is the step of transferring the first solid electrolyte layer SE1 to the positive electrode side sheet 200 using the first positive electrode side transfer roller 120. Specifically, in the first solid electrolyte layer transfer step S2, the first solid electrolyte layer SE1 is positioned within a range guided by a guide roller (not shown). Then, the paste constituting the first solid electrolyte layer SE1 is pressurized and passed through the positive electrode side sheet 200 by a pair of first positive electrode side transfer rollers 120 to perform transfer pressing. Regarding the pressure at this time, for example, the pressure is set to 50 to 500 MPa at room temperature (e.g., 10 to 35°C). Preferably, it is 100 MPa at 25°C.

[0102] The substrate peeling step S3 is the step of peeling the substrate sheet 123 from the first solid electrolyte layer SE1 pressed by the peeling roller 130. Specifically, the substrate peeling step S3 includes an identification step S30, a peeling start point control step S31, and a peeling step S32.

[0103] The identification step S30 is the step of identifying the peeling start point P of the substrate sheet 123. That is, as described above, the identification unit 300 continuously monitors the peeling start point P by identifying it. In addition, the information of the peeling start point P identified by the identification unit 300 is output to the control unit 400.

[0104] The peeling start point control step S31 is a step that controls the peeling start point P to be at a predetermined position. As described above, the predetermined position is the ideal position of the peeling start point P. The control unit 400 performs feedback control on the rotation speed of the substrate roll 131 so that the peeling start point P identified by the recognition unit 300 is at this predetermined position. The specific control content is as described above, so its description is omitted here.

[0105] The peeling step S32 is a step of peeling the substrate sheet 123 in the opposite direction to the transport direction of the positive electrode side sheet 200, based on the peeling starting point P which is controlled at a predetermined position. That is, the rotation speed of the substrate roll 131 is controlled by the control unit 400, thereby controlling the peeling starting point P to be at a predetermined position. Based on this position, the substrate sheet 123 is peeled in the opposite direction to the transport direction by the peeling roller 130 arranged upstream of the peeling starting point P.

[0106] The positive electrode pressing step S4 is a step in which the positive electrode side sheet 200, on which the first solid electrolyte layer SE1 is transferred, is pressed by the positive electrode pressing roller 180. This positive electrode pressing step S4 increases the density of the positive electrode. The pressing pressure used for increasing density is, for example, about 800-1200 MPa at 25-100°C. The laminate of the high-density positive electrode side sheet 200 and the first solid electrolyte layer SE1 is transported downstream on the transport line.

[0107] The second solid electrolyte layer transfer step S5 is a step after the positive electrode pressing step S4, in which the second solid electrolyte layer SE2 is transferred onto the positive electrode side sheet 200 on which the first solid electrolyte layer SE1 has been transferred and pressed, using the second positive electrode side transfer roller 140. Specifically, in the second solid electrolyte layer transfer step S5, the second solid electrolyte layer SE2 is positioned on the positive electrode side sheet 200 on which the first solid electrolyte layer SE1 has been transferred, so that it is arranged within the range guided by a guide roller (not shown). Then, the paste constituting the second solid electrolyte layer SE2 is pressurized and passed through the positive electrode side sheet 200 by the second positive electrode side transfer roller 140, which serves as a transfer roller, to perform transfer pressing. Regarding the pressure at this time, for example, at room temperature (e.g., 10~35°C), the pressure is set to 50~500 MPa, preferably 150 MPa at 25°C. In this way, the positive electrode side sheet 200 is pressurized more than twice.

[0108] On the other hand, prepare the negative electrode side sheet 210 at a location away from the transport line. First, as... Figure 5 As shown on the upper side, the intermediate layer 5 is transferred to the negative electrode active material layer 21 stacked on the negative electrode current collector foil 22a by the intermediate layer transfer roller 150 (intermediate layer transfer step S6). Then, as... Figure 5 As shown on the lower side, the negative electrode-side solid electrolyte layer SE3 is transferred onto the intermediate layer 5 by the negative electrode-side transfer roller 160 to form the negative electrode-side sheet 210 (negative electrode-side solid electrolyte layer transfer step S7). Thus, the intermediate layer 5 is disposed between the negative electrode active material layer 21 and the negative electrode-side solid electrolyte layer SE3. Furthermore, in this embodiment, the negative electrode-side sheet 210 comprises a laminate of the negative electrode current collector foil 22a, the negative electrode active material layer 21, the intermediate layer 5, and the negative electrode-side solid electrolyte layer SE3, but it may also omit the negative electrode active material layer 21 and the intermediate layer 5.

[0109] In the intermediate layer transfer step S6, the paste constituting the intermediate layer 5 is positioned on the negative electrode active material layer 21 and placed within a range guided by a guide roller (not shown). Then, the intermediate layer 5 is pressed onto the negative electrode active material layer 21 by the intermediate layer transfer roller 150, which acts as a transfer roller, and is passed through it to perform intermediate layer transfer pressing, transferring the intermediate layer 5 to the negative electrode active material layer 21. Regarding the pressure at this time, for example, at room temperature (e.g., 10~35°C), the pressure is set to 50~800 MPa. More preferably, it is in the range of 300 MPa or more and 800 MPa or less at 25°C.

[0110] In the negative electrode side solid electrolyte layer transfer step S7, the slurry constituting the negative electrode side solid electrolyte layer SE3 is positioned on the intermediate layer 5 and placed within the range guided by a guide roller (not shown). Then, the negative electrode side solid electrolyte layer SE3 is pressed onto the intermediate layer 5 by the negative electrode side transfer roller 160, which acts as a transfer roller, and is forced through it to perform a negative electrode active material layer transfer pressing that transfers the negative electrode side solid electrolyte layer SE3 to the intermediate layer 5. Regarding the pressure at this time, for example, the pressure is set to 600-800 MPa at room temperature (e.g., 10-35°C).

[0111] Furthermore, regarding pressure, the pressing pressure in the positive electrode pressing step S4 is not only the maximum pressure applied to the positive electrode sheet 200, but also the maximum pressure applied in the entire pressing apparatus method. To increase energy density and densify the electrode, the positive electrode sheet 200 is pressed under high pressure. The maximum pressing pressure in the positive electrode pressing step S4 is greater than or equal to the maximum pressing pressure applied to the negative electrode sheet 210.

[0112] Furthermore, the pressure during the transfer of the first solid electrolyte layer in step S2 and the second solid electrolyte layer in step S5 is lower than the pressing pressure during the positive electrode pressing step S4. Additionally, the pressure during the transfer of the first solid electrolyte layer in step S2 and the second solid electrolyte layer in step S5 is lower than the pressing pressure during the negative electrode side solid electrolyte layer transfer step S7.

[0113] Because the first solid electrolyte layer SE1 and the second solid electrolyte layer SE2 contain a relatively large amount of binder, the pressing pressure during transfer can be reduced. Furthermore, by setting the transfer pressing pressure as low as possible, the extension of the first solid electrolyte layer SE1 and the second solid electrolyte layer SE2 caused by the pressing during transfer can be reduced. Therefore, leeway for the extension of the first solid electrolyte layer SE1 and the second solid electrolyte layer SE2 in subsequent integration pressing steps such as S9 can be preserved, allowing the first solid electrolyte layer SE1 to extend along with the positive electrode layer 4. This improves the adhesion between the first solid electrolyte layer SE1 and the positive electrode active material layer 41.

[0114] Furthermore, after the negative electrode side solid electrolyte layer transfer step S7, the formed negative electrode side sheet 210 is cut by a cutter while being supported by a delivery roller that delivers the component transferred in the negative electrode side solid electrolyte layer transfer step S7. The negative electrode side sheet 210 is cut to the design size of the negative electrode layer 2 of the solid-state battery 1.

[0115] like Figure 2 and Figure 6As shown, the negative electrode side sheet 210, cut to the designed dimensions, is transported to the positive electrode side sheet 200 via a transport line that merges with that of the positive electrode side sheet 200, and then stacked on top of the positive electrode side sheet 200. At this time, before the integrated pressing step S9 described later, a first solid electrolyte layer SE1 is provided on the lower side of the positive electrode side sheet 200 opposite to the negative electrode side solid electrolyte layer SE3, and a second solid electrolyte layer SE2 is provided thereon. Furthermore, the negative electrode side sheet 210 is disposed on the positive electrode side sheet 200 in a cut state.

[0116] Specifically, in the negative electrode side sheet lamination step S8, a negative electrode side sheet 210, on which a first solid electrolyte layer SE1 and a second solid electrolyte layer SE2 have been transferred, is transported and laminated on the positive electrode side sheet 200 by the negative electrode side sheet lamination roller 170. In the negative electrode side sheet lamination step S8, a negative electrode side sheet 210 cut to the designed size is positioned on the positive electrode side sheet 200 on which the first solid electrolyte layer SE1 and the second solid electrolyte layer SE2 have been transferred, and positioned within the range guided by a guide roller (not shown).

[0117] Thus, with the positive electrode sheet 200 and the negative electrode sheet 210 stacked, the electrode 10 is integrated by pressing with the integrated pressing roller 190 (integration pressing step S9). Before the integration pressing step S9, the thickness of the positive electrode sheet 200 is greater than that of the negative electrode sheet 210 in the stacking direction. The pressure at this time is, for example, about 500-900 MPa at 25-100°C. Through the integration pressing step S9, while integrating the positive electrode sheet 200 and the negative electrode sheet 210, the first solid electrolyte layer SE1, the second solid electrolyte layer SE2, and the negative electrode solid electrolyte layer SE3 are increased in density. When comparing the pressing pressure of the integration pressing step S9 and the positive electrode pressing step S4, the pressing pressure of the positive electrode pressing step S4 is greater than the pressing pressure of the integration pressing step S9.

[0118] After the integrated pressing step S9, the formed electrode 10 is cut off by a rotary cutter.

[0119] Furthermore, the transfer of the first solid electrolyte layer SE1 in the first solid electrolyte layer transfer step S2, the pressing of the positive electrode side sheet 200 in the positive electrode pressing step S4, the transfer of the second solid electrolyte layer SE2 in the second solid electrolyte layer transfer step S5, the pre-integration lamination of the negative electrode side sheet 210 in the negative electrode side sheet lamination step S8, and the integration pressing in the integration pressing step S9 are all performed on both sides of the positive electrode side sheet 200 sent out through the positive electrode side sheet conveying step S1. Thus, a result can be obtained... Figure 1 The solid-state battery 1 is shown in which the positive electrode side sheet 200 is symmetrically stacked on the upper and lower surfaces.

[0120] Thus, in this embodiment, by peeling the substrate sheet 123 in a direction opposite to the transport direction of the positive electrode sheet 200 and pulling the substrate sheet 123 in a direction opposing the transport direction, an appropriate shear force can be generated between the first solid electrolyte layer SE1 and the substrate sheet 123 compared to, for example, when the transport direction and the peeling direction are the same. This can suppress bending of the positive electrode sheet 200 or breakage of the positive electrode sheet 200 starting from such bending. As a result, the peelability when peeling the substrate sheet 123 from the first solid electrolyte layer SE1 can be improved.

[0121] The embodiments have been described above with reference to the accompanying drawings, but the present invention is not limited to these embodiments. It is obvious that those skilled in the art will conceive of various modifications or alterations within the scope of the technical solutions described, and it should be understood that these modifications and alterations also fall within the technical scope of the present invention. Furthermore, the constituent elements of the above embodiments can be combined arbitrarily without departing from the spirit of the invention.

[0122] For example, in the above embodiment, as an example of peeling the substrate sheet 123 in a direction opposite to the transport direction of the positive electrode sheet 200, the substrate sheet 123 is peeled off by controlling the peeling start point P at a predetermined position through feedback control performed by the recognition unit 300 and the control unit 400. However, as long as the structure of peeling the substrate sheet 123 in a direction opposite to the transport direction is adopted, other methods can also be applied. For example, such as Figure 7 As shown, a guide mechanism 500 can also be provided for peeling the substrate sheet 123 in the opposite direction to the transport direction, starting from the peeling point P. When such a structure is adopted, for example, the peeling of the substrate sheet 123 in the opposite direction to the transport direction can be achieved without providing the aforementioned identification part 300 and other structures.

[0123] Furthermore, in the above embodiments, various solid electrolyte layers are stacked on both sides of the positive electrode sheet 200, but the stacking may also be a structure that is stacked only on one side.

[0124] At least the following items are described in this specification. Additionally, the corresponding components in the above embodiments are shown in parentheses, but this is not a limitation.

[0125] (1) A peeling mechanism (peeling mechanism 132) peels a substrate (substrate sheet 123) from a transfer body (first solid electrolyte layer SE1) transferred to a parent material sheet (positive electrode side sheet 200), wherein,

[0126] The stripping mechanism includes:

[0127] A peeling roller (peeling roller 130) peels the substrate from the transfer body; and

[0128] A substrate roll (substrate roll 131) is used to wind up the substrate that has been peeled off by the peeling roller.

[0129] The peeling roller peels the substrate in a direction opposite to the transport direction of the parent material sheet.

[0130] According to (1), by peeling the substrate in a direction opposite to the transport direction of the base sheet and pulling the substrate in a direction opposing the transport direction of the base sheet, a suitable shear force can be generated between the base sheet and the transfer body compared to, for example, peeling the substrate in the same direction as the transport direction. As a result, it is possible to suppress bending of the base sheet or breakage starting from such bending. In other words, the peelability of the substrate when peeling it from the transfer body can be improved.

[0131] (2) The stripping mechanism according to (1), wherein,

[0132] The peeling roller is positioned upstream of the peeling start point (peeling start point P) in the transport direction.

[0133] According to (2), in the transport direction, the peeling roller is located upstream of the peeling start point of the substrate, so that the substrate can be reliably pulled in the opposite direction to the transport direction, thus generating appropriate shear force between the parent material and the transfer body.

[0134] (3) The stripping mechanism according to (2), wherein,

[0135] The stripping mechanism also includes:

[0136] The identification unit (identification unit 300) identifies the stripping start point; and

[0137] The control unit (control unit 400) controls the rotational speed of the substrate roll.

[0138] The control unit controls the rotation speed of the substrate roll, so that the peeling start point identified by the recognition unit is at a predetermined position.

[0139] According to (3), by performing feedback control based on the identification unit to make the peeling start point at a specified position, stable substrate peeling can be achieved.

[0140] (4) The stripping mechanism according to (3), wherein,

[0141] When the peeling start point is located downstream of the predetermined position, the control unit increases the rotational speed of the substrate roll.

[0142] When the peeling start point is located upstream of the predetermined position, the control unit reduces the rotation speed of the substrate roll.

[0143] According to (4), the winding speed of the substrate at the substrate roll is sometimes inconsistent with the transport speed of the parent sheet. In this case, the peeling start point deviates from the specified position, but by controlling the rotation speed of the substrate roll according to the deviation from the specified position, the peeling start point can be controlled at the specified position. Thus, stable substrate peeling can be achieved.

[0144] (5) The stripping mechanism according to (2), wherein,

[0145] On the base material sheet on which the transfer body is transferred, the peeling start line connecting the peeling start point is configured to be inclined relative to the width direction orthogonal to the transport direction.

[0146] According to (5), the substrate can be peeled along a peeling start line that is inclined in the width direction. For example, stress concentration at the specified peeling start point can be suppressed, and as a result, the peelability of the substrate can be improved.

[0147] (6) The stripping mechanism according to (5), wherein,

[0148] The stripping roller is configured such that one side of the stripping roller is inclined relative to the other side in the width direction.

[0149] According to (6), in the width direction, one side of the peeling roller is inclined relative to the other side, thereby enabling substrate peeling along the peeling start line.

[0150] (7) The stripping mechanism according to (1) or (2), wherein,

[0151] The transfer body is a solid electrolyte layer (first solid electrolyte layer SE1).

[0152] The parent material sheet is a positive electrode side sheet (positive electrode side sheet 200).

[0153] According to (7), the substrate can be properly peeled off from the solid electrolyte layer transferred to the positive electrode side sheet.

[0154] (8) A peeling method for peeling a substrate (substrate sheet 123) from a transfer body (first solid electrolyte layer SE1) transferred to a base material sheet (positive electrode side sheet 200), wherein,

[0155] The stripping method comprises:

[0156] Identification step (identification step S30) for identifying the peeling start point (peeling start point P) of the substrate.

[0157] The peeling start point control step (peeling start point control step S31) controls the peeling start point to a predetermined position; and

[0158] Based on the peeling starting point controlled to the specified position, a peeling step (peeling step S32) is performed to peel the substrate in the opposite direction to the transport direction of the parent material sheet.

[0159] According to (8), by controlling the peeling start point at a specified position, and starting from this controlled position, peeling the substrate in the opposite direction to the transport direction, stable substrate peeling can be achieved. This suppresses bending and breakage of the base material, and improves the peelability of the substrate.

Claims

1. A peeling mechanism that peels a substrate from a transfer body transferred to a base material sheet, wherein, The stripping mechanism includes: A peeling roller that peels the substrate from the transfer body; and A substrate roll that takes up the substrate that has been peeled off by the peeling roller. The peeling roller peels the substrate in a direction opposite to the transport direction of the parent material sheet.

2. The stripping mechanism according to claim 1, wherein, The peeling roller is positioned upstream of the peeling start point in the transport direction relative to the peeling start point of the substrate.

3. The stripping mechanism according to claim 2, wherein, The stripping mechanism also includes: The identification unit identifies the stripping start point; and The control unit controls the rotational speed of the substrate roll. The control unit controls the rotation speed of the substrate roll, so that the peeling start point identified by the recognition unit is at a predetermined position.

4. The stripping mechanism according to claim 3, wherein, When the peeling start point is located downstream of the predetermined position, the control unit increases the rotational speed of the substrate roll. When the peeling start point is located upstream of the predetermined position, the control unit reduces the rotation speed of the substrate roll.

5. The stripping mechanism according to claim 2, wherein, On the base material sheet on which the transfer body is transferred, the peeling start line connecting the peeling start point is configured to be inclined relative to the width direction orthogonal to the transport direction.

6. The stripping mechanism according to claim 5, wherein, The stripping roller is configured such that one side of the stripping roller is inclined relative to the other side in the width direction.

7. The stripping mechanism according to claim 1 or 2, wherein, The transfer body is a solid electrolyte layer. The parent material sheet is the positive electrode side sheet.

8. A peeling method for peeling a substrate from a transfer body transferred to a base material sheet, wherein, The stripping method comprises: The identification step for identifying the peeling start point of the substrate; The peeling start point is controlled to a predetermined position by a peeling start point control step; and The peeling step involves peeling the substrate in a direction opposite to the transport direction of the parent material sheet, based on the peeling start point controlled to the specified position.

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