Method for manufacturing solid-state batteries

Abstract

Provided is a method for manufacturing solid-state batteries, whereby continuous and high-productivity manufacturing can be achieved while optimizing the adhesion and interface formation of each layer. The method for manufacturing solid-state batteries comprises: a positive electrode-side sheet member feeding step for feeding a positive electrode-side sheet member; a first solid electrolyte layer transfer step for transferring a first solid electrolyte layer to the positive electrode-side sheet member; a positive electrode pressing step for pressing the positive electrode-side sheet member to which the first solid electrolyte layer has been transferred; a negative electrode-side solid electrolyte layer transfer step for transferring a negative electrode-side solid electrolyte layer to a negative electrode active material layer to form a negative electrode-side sheet member; a negative electrode-side sheet member lamination step for laminating the negative electrode-side sheet member on the positive electrode-side sheet member; and an integrated pressing step for pressing the positive electrode-side sheet member and the negative electrode-side sheet member in a laminated state. Each step is successively performed on the positive electrode-side sheet member.

Description

Solid-state battery manufacturing method

[0001] The present invention relates to a method for manufacturing a solid-state battery.

[0002] In recent years, research and development into secondary batteries that contribute to energy efficiency has been conducted to ensure that more people have access to affordable, reliable, sustainable and advanced energy.

[0003] As a method for automatically manufacturing secondary batteries with high productivity, a manufacturing method has been proposed in which materials such as a positive electrode layer, a solid electrolyte layer, and a negative electrode layer are fed and pressed with rolls to obtain a solid battery (see, for example, Patent Document 1).

[0004] Japanese Patent Application Laid-Open No. 2023-085663

[0005] When a solid electrolyte layer is formed in a plurality of layers, it is required to continuously manufacture a solid-state battery with high productivity while optimizing the adhesion and interface formation of each layer.

[0006] (1) The present invention provides a cathode sheet member feeding step (e.g., cathode side sheet member feeding step S1) of feeding a cathode side sheet member (e.g., cathode side sheet member 300) in which a cathode active material layer (e.g., cathode active material layer 31) is laminated on a cathode current collector foil (e.g., cathode current collector foil 321); a first solid electrolyte layer transferring step (e.g., first solid electrolyte layer transferring step S2) of transferring a first solid electrolyte layer (e.g., first solid electrolyte layer SE1) to the cathode side sheet member; a cathode pressing step (e.g., cathode pressing step S3) of pressing the cathode side sheet member to which the first solid electrolyte layer has been transferred; and a cathode pressing step (e.g., anode side solid electrolyte layer SE3) of transferring a negative electrode side solid electrolyte layer (e.g., anode active material layer 21) laminated on a negative electrode current collector foil (e.g., anode current collector foil 221) to form a negative electrode. a negative electrode-side sheet member lamination step (e.g., negative electrode-side sheet member lamination step S8) of laminating the negative electrode-side sheet member, to which the negative electrode-side solid electrolyte layer has been transferred, on the positive electrode-side sheet member to which at least the first solid electrolyte layer has been transferred; and an integration pressing step (e.g., integration pressing step S9) of pressing the stacked positive electrode-side sheet member and the negative electrode-side sheet member to integrate the electrodes, wherein the first solid electrolyte layer transfer step, the positive electrode pressing step, the negative electrode-side sheet member lamination step, and the integration pressing step are performed consecutively on the positive electrode-side sheet member.

[0007] (2) It is preferable that the method further includes, after the positive electrode pressing step, a second solid electrolyte layer transferring step (e.g., second solid electrolyte layer transferring step S4) of transferring a second solid electrolyte layer (e.g., second solid electrolyte layer SE2) onto the pressed positive electrode-side sheet member, and that the negative electrode-side sheet member laminating step includes laminating the negative electrode-side sheet member onto which the negative electrode-side solid electrolyte layer has been transferred, on the positive electrode-side sheet member onto which the second solid electrolyte layer has been transferred.

[0008] (3) The thickness of the first solid electrolyte layer and the thickness of the negative electrode side solid electrolyte layer are preferably thinner than the thickness of the second solid electrolyte layer.

[0009] (4) It is preferable that the method further includes an intermediate layer transferring step (e.g., intermediate layer 5) of transferring an intermediate layer onto the anode active material layer, and that the anode-side solid electrolyte layer transferring step forms the anode-side sheet member by transferring the anode-side solid electrolyte layer onto the intermediate layer, and that the intermediate layer is disposed between the anode active material layer and the anode-side solid electrolyte layer.

[0010] (5) It is preferable that the method further includes a cutting step (for example, cutting step S10) of cutting the formed electrodes after the integration pressing step.

[0011] (6) It is preferable that the method further includes an anode-side sheet member cutting step (e.g., anode-side sheet member cutting step S7) of cutting the anode-side sheet member after the anode-side solid electrolyte layer transferring step, and the anode-side sheet member is laminated on the cathode-side sheet member in a cut state.

[0012] (7) It is preferable that the pressure applied during the transfer in the first solid electrolyte layer transfer step and the second solid electrolyte layer transfer step is lower than the pressing pressure applied during the positive electrode pressing step.

[0013] (8) The pressure during the transfer in the first solid electrolyte layer transfer step and the second solid electrolyte layer transfer step is preferably lower than the pressure during the transfer in the negative electrode side solid electrolyte layer transfer step.

[0014] (9) The pressure applied in the positive electrode pressing step is preferably greater than the pressure applied in the integration pressing step.

[0015] (10) It is preferable that the transfer of the first solid electrolyte layer in the first solid electrolyte layer transfer step, the pressing of the positive electrode side sheet member in the positive electrode pressing step, the lamination of the negative electrode side sheet member in the negative electrode side sheet member lamination step, and the integration pressing in the integration pressing step are performed on both surfaces of the positive electrode side sheet member fed in the positive electrode side sheet member feeding step.

[0016] (11) The first solid electrolyte layer transferring step and the second solid electrolyte layer transferring step preferably include an alignment step (e.g., alignment steps S21 and S41) of aligning the first solid electrolyte layer and the second solid electrolyte layer on the positive electrode-side sheet member, respectively, and a transfer pressing step of transferring and pressing the first solid electrolyte layer and the second solid electrolyte layer with transfer rollers (e.g., first positive electrode-side transfer roller 310 and second positive electrode-side transfer roller 320).

[0017] (12) It is preferable that the intermediate layer transferring step includes an intermediate layer positioning step (e.g., intermediate layer positioning step S51) of aligning the intermediate layer on the anode active material layer, and an intermediate layer transfer press step (e.g., intermediate layer transfer roller 370) of transferring and pressing the intermediate layer onto the anode active material layer, and that the anode-side solid electrolyte layer transferring step includes an anode-side solid electrolyte layer positioning step (e.g., anode-side solid electrolyte layer positioning step S61) of aligning the anode-side solid electrolyte layer on the intermediate layer transferred to the anode active material layer, and an anode-side solid electrolyte layer transfer press step (anode-side solid electrolyte layer transfer press step S62) of transferring and pressing the anode-side solid electrolyte layer onto the intermediate layer with an anode-side transfer roller (e.g., anode-side transfer roller 330).

[0018] (13) The present invention provides a method for manufacturing a cathode sheet member including: a first cathode transfer roller (e.g., first cathode transfer roller 310) that transfers a first solid electrolyte layer onto a cathode sheet member having a cathode active material layer laminated on a cathode current collector foil; a cathode press device that presses the cathode sheet member onto which the first solid electrolyte layer has been transferred; a cathode transfer roller that transfers the anode solid electrolyte layer onto the anode active material layer laminated on an anode current collector foil to form a anode sheet member; and a cathode sheet member having the anode solid electrolyte layer transferred onto the cathode sheet member onto which at least the first solid electrolyte layer has been transferred. and an integration press device (e.g., integration press device 360) that presses the positive electrode side sheet member and the negative electrode side sheet member in a stacked state so that the electrodes are integrated, in which the first positive electrode side transfer roller, the positive electrode press device, the negative electrode side sheet member stacking roller, and the integration press device are arranged in order from the upstream side along the feeding direction of the positive electrode side sheet member.

[0019] According to the above (1), a solid state battery having a plurality of solid electrolyte layers, such as a first solid electrolyte layer and an anode-side solid electrolyte layer, is manufactured by continuously transferring or pressing the layers on a cathode-side sheet member. This makes it possible to continuously manufacture solid state batteries with high productivity while optimizing the adhesion and interface formation of each layer.

[0020] According to the above (2), it is possible to manufacture a solid-state battery having three layers, i.e., a first solid electrolyte layer, a second solid electrolyte layer, and an anode-side solid electrolyte layer, with high productivity. In addition, by performing the first solid electrolyte layer transfer step and the second solid electrolyte layer transfer step at different temperatures and pressures, it is possible to manufacture the solid electrolyte layers in an optimal environment and under optimal conditions while continuously feeding out the cathode-side sheet member.

[0021] According to the above feature (3), the first solid electrolyte layer can be made to conform to the positive electrode layer, and the negative electrode-side solid electrolyte layer can be made to conform to the negative electrode layer, making it easier to attach them, while the second solid electrolyte layer can be made to stably bond them together. Furthermore, solid electrolyte layers having different thicknesses can be continuously produced in an optimal environment and conditions.

[0022] According to the above (4), by providing the intermediate layer, when the solid-state battery is a lithium metal battery, it becomes possible to uniformly deposit lithium metal, and the interface between the intermediate layer and the solid electrolyte layer can be stabilized.

[0023] According to the above (5), a plurality of electrodes can be obtained from a laminate in which the negative electrode layer and each solid electrolyte layer are laminated on the positive electrode side sheet member 300, thereby improving productivity.

[0024] According to the above (6), the negative electrode sheet member may be softer than the positive electrode sheet member. In this case, by cutting the negative electrode sheet member and transferring the cut sheet to the positive electrode sheet member, it becomes possible to more precisely control the dimensions of the negative electrode layer. Therefore, solid-state batteries can be manufactured continuously and with high productivity.

[0025] According to the above (7), the first solid electrolyte layer and the second solid electrolyte layer can be transferred with a necessary and suitable pressure, and the positive electrode layer can be made dense and have a high energy density. This makes it possible to continuously manufacture solid-state batteries having a plurality of layers while pressing them with a pressure required for the attributes of each layer.

[0026] According to the above (8), when the target to which the anode-side solid electrolyte layer is to be transferred (the intermediate layer if the solid-state battery includes an intermediate layer) does not contain a binder, it is preferable to transfer the anode-side solid electrolyte layer with a relatively strong pressure. In this way, the anode-side solid electrolyte layer can be transferred with a necessary and suitable pressure.

[0027] According to the above (9), the positive electrode layer requires high pressure to be highly densified. On the other hand, once the positive electrode sheet member is pressed, and the second solid electrolyte layer, the negative electrode solid electrolyte layer, and the like are laminated on the positive electrode sheet member, the layers are stably integrated without applying pressure until the positive electrode pressing step. Therefore, it is possible to continuously manufacture the solid-state battery 1 while pressing the solid-state battery with the pressure required for the properties of each layer.

[0028] According to the above (10), a solid state battery can be obtained in which a solid electrolyte layer and an anode layer are symmetrically formed on both sides of the cathode-side sheet member.

[0029] According to (11) above, each transfer step includes a positioning step and a transfer press step, which makes it possible to control the transfer position more accurately.

[0030] According to the above (12), it becomes possible to more accurately control the transfer position in the intermediate layer transferring step S5 and the negative electrode side solid electrolyte layer transferring step S6.

[0031] According to the above (13), a solid state battery having a plurality of solid electrolyte layers, such as a first solid electrolyte layer and an anode-side solid electrolyte layer, is manufactured by continuously transferring or pressing the layers on a cathode-side sheet member. This makes it possible to manufacture the solid state battery 1 continuously and with good productivity while optimizing the adhesion and interface formation of each layer.

[0032] Fig. 1 is a diagram showing a cross section of a solid-state battery of the present embodiment; Fig. 2 is a diagram showing a manufacturing system for a solid-state battery of the present embodiment; Fig. 3 is a diagram showing a part of the manufacturing system for a solid-state battery of the present embodiment; Fig. 4 is a diagram showing a flow of a manufacturing method for a solid-state battery of the present embodiment; Fig. 5 is a diagram explaining positions at which each layer constituting the solid-state battery of the present embodiment is cut.

[0033] [Solid-State Battery] The solid-state battery 1 manufactured by the manufacturing method according to the present invention is an all-solid-state battery having an electrode 10 in which an anode layer 2, a solid electrolyte layer 4, and a cathode layer 3 are stacked in this order, as shown in Fig. 1. In this embodiment, the structure in which the anode layer 2, the solid electrolyte layer 4, the cathode layer 3, the solid electrolyte layer 4, and the anode layer 2 are stacked in this order as shown in Fig. 1 will be described as the stacked structure of the solid-state battery 1. However, the structure of the solid-state battery 1 is not limited to the above. The solid-state battery 1 may have a configuration that can be used in a solid-state battery, such as an exterior body, in addition to the electrode 10 shown in Fig. 1.

[0034] The solid electrolyte layer 4 in the solid battery 1 has at least a first solid electrolyte layer SE1 arranged on the cathode layer 3 side and an anode-side solid electrolyte layer SE3 arranged on the anode layer 2 side. The solid electrolyte layer 4 may also have a second solid electrolyte layer SE2 arranged adjacent to the first solid electrolyte layer SE1. In this embodiment, the solid electrolyte layer 4 will be described as consisting of the above three layers. An intermediate layer 5 may be optionally arranged between the anode layer 2 and the solid electrolyte layer 4.

[0035] The solid state battery 1 is not particularly limited, but may be a lithium ion solid state secondary battery or a lithium metal secondary battery.

[0036] (Negative Electrode Layer) 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 made of a material that can be used as a negative electrode active material for the solid state battery 1. Examples of the negative electrode active material that makes up the negative electrode active material layer 21 include silicon-based active materials such as lithium metal, lithium alloys, Si, and Si alloys, and lithium titanate (Li ４ Ti ５ O １２ ), lithium transition metal oxides such as TiO ２ , Nb ２ O ３ and W.O. ３ Examples of the material include transition metal oxides such as those mentioned above, metal sulfides, metal nitrides, carbon materials such as graphite, soft carbon and hard carbon, and metallic indium.

[0037] The anode active material layer 21 may contain materials that can be contained in the anode active material layer 21 of the solid battery 1 in addition to the above. Examples of such materials include a solid electrolyte, a conductive additive, a binder, etc. Examples of the solid electrolyte include the same solid electrolyte as that contained in the solid electrolyte layer 4 described below. Examples of the conductive additive include carbon black, natural graphite, carbon fiber, and carbon nanotubes. Examples of the binder include a nitrile-based polymer, a polyester-based polymer, an acrylic acid-based polymer, a cellulose-based polymer, a styrene-based polymer, a styrene-butadiene-based polymer, a vinyl acetate-based polymer, a urethane-based polymer, and a fluoroethylene-based polymer.

[0038] The negative electrode current collector layer 22 is not particularly limited, but may be made of copper, nickel, stainless steel, etc. Examples of the shape of the negative electrode current collector layer 22 include a foil, a plate, a mesh, a nonwoven fabric, and a foam. In this embodiment, the negative electrode current collector layer 22 is made of a negative electrode current collector foil 221.

[0039] (Solid Electrolyte Layer) The solid electrolyte layer 4 is formed between the anode layer 2 and the cathode layer 3. In this embodiment, the solid electrolyte layer 4 has a structure in which a first solid electrolyte layer SE1 arranged in contact with the cathode layer, a second solid electrolyte layer SE2, and an anode-side solid electrolyte layer SE3 arranged on the anode layer side are stacked in this order.

[0040] The first solid electrolyte layer SE1 is disposed in contact with the positive electrode active material layer 31 of the positive electrode layer 3. The solid electrolyte constituting the first solid electrolyte layer SE1 is not particularly limited, and may be any material that can be used as an electrolyte in a solid-state battery. Examples include inorganic solid electrolytes such as sulfide solid electrolytes, oxide solid electrolytes, halide solid electrolytes, and lithium-containing salts, and polymer solid electrolytes such as polyethylene oxide. One type of the above solid electrolytes may be used, or two or more types may be used in combination.

[0041] The first solid electrolyte layer SE1 contains a binder in addition to the solid electrolyte material. The binder may be the same as the binder that can be contained in the negative electrode active material layer 21. The content of the binder in the first solid electrolyte layer SE1 relative to the total mass of the first solid electrolyte layer SE1 is equal to or greater than the 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 content of the binder in the first solid electrolyte layer SE1 is, for example, 25% by mass. The content of the binder in the first solid electrolyte layer SE1 is preferably 10 to 30% by mass. This allows the first solid electrolyte layer SE1 to easily follow the positive electrode layer 3 and extend when the positive electrode layer 3 is pressed. Furthermore, the pressing pressure in the transfer pressing step described below can be reduced.

[0042] The first solid electrolyte layer SE1 may contain, in addition to the solid electrolyte material and binder, materials that can be used in a solid electrolyte layer of a solid-state battery.

[0043] 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 3 to 15 μm, for example.

[0044] The second solid electrolyte layer SE2 is an arbitrarily disposed layer and is 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 may be the same as the solid electrolyte material constituting the first solid electrolyte layer SE1. Like the first solid electrolyte layer SE1, the second solid electrolyte layer SE2 may contain a binder or the like in addition to the solid electrolyte material. The content of the binder in the second solid electrolyte layer SE2 is equal to or less than the content of the binder in the first solid electrolyte layer SE1. The content of the binder in the second solid electrolyte layer SE2 is preferably 10 to 30 mass %. This improves the energy density of the solid battery 1. The second solid electrolyte layer SE2 may include a support. The support may be a three-dimensional structure such as a mesh, a woven fabric, a nonwoven fabric, an embossed body, a punched body, an expanded body, or a foam. The second solid electrolyte layer SE2 may not include the support.

[0045] The thickness of the second solid electrolyte layer SE2 (the length of each layer in the stacking direction) is preferably greater than the thickness of the first solid electrolyte layer SE1. The thickness of the second solid electrolyte layer SE2 (the length of each layer in the stacking direction) is also preferably greater than the thickness of the anode-side solid electrolyte layer SE3, which will be described later. The thickness of the second solid electrolyte layer SE2 is preferably, for example, 10 to 50 μm.

[0046] The anode-side solid electrolyte layer SE3 is disposed on the anode layer side. The anode-side solid electrolyte layer SE3 is disposed adjacent to the anode layer 2. When the solid battery 1 has an intermediate layer 5 as shown in FIG. 1 , the anode-side solid electrolyte layer SE3 may be disposed adjacent to the intermediate layer 5.

[0047] The solid electrolyte material constituting the anode-side solid electrolyte layer SE3 is not particularly limited and may be the same material as the solid electrolyte material constituting the first solid electrolyte layer SE1. The content of the binder in the anode-side solid electrolyte layer SE3 is preferably 1.3 to 8.7 mass%. In terms of volume%, the content of the binder in the anode-side solid electrolyte layer SE3 is preferably 2.7 volume% or more and 10 volume% or less. The content of the binder in the anode-side solid electrolyte layer SE3 is less than the content of the binder in the first solid electrolyte layer SE1.

[0048] The thickness of the anode-side solid electrolyte layer SE3 (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 anode-side solid electrolyte layer SE3 is preferably 3 to 8.5 μm, for example.

[0049] (Positive Electrode Layer) The positive electrode layer 3 has a positive electrode active material layer 31 and a positive electrode current collector layer 32. In this embodiment, the positive electrode layer 3 has a configuration in which two positive electrode active material layers 31 are stacked on both sides of one positive electrode current collector layer 32. However, the configuration of the positive electrode layer 3 is not limited to the above, and the positive electrode layer 3 may have a configuration in which one positive electrode active material layer 31 is stacked on one side of one positive electrode current collector layer 32.

[0050] The positive electrode active material layer 31 is not particularly limited and can be made of a material that can be used as a positive electrode active material for a solid-state battery. Examples of the positive electrode active material that can be used to make the positive electrode active material layer 31 include LiCoO２ , LiNiO ２ , LiCo ｘ Ni ｙ Mn ｚ O ２ (x+y+z=1), LiVO ２ , LiCrO ２ Layered positive electrode active material particles such as LiMn ２ O ４ , Li(Ni ０．２５ Mn ０．７５ ) ２ O ４ , LiCoMnO ４ , Li ２ NiMn ３ O ８ Spinel-type positive electrode active materials such as LiCoPO ４ , LiMnPO ４ , LiFePO ４ Olivine-type positive electrode active materials such as solid solution oxides (Li ２ MnO ３ -LiMO ２ (M=Co, Ni, etc.), conductive polymers such as polyaniline and polypyrrole, Li ２ S, CuS, Li-Cu-S compound, TiS ２ , FeS, MoS ２ , sulfides such as Li—Mo—S compounds, mixtures of sulfur and carbon, etc. The positive electrode active material may be one of the above materials, or may be composed of two or more of the above materials.

[0051] The positive electrode active material layer 31 may contain a binder or the like. The binder content of the positive electrode active material layer 31 is preferably 0.5 to 5 mass %. Preferably, it may be 2.56 mass %. The thickness of the positive electrode active material layer 31 (the length of each layer in the stacking direction) is preferably 80 to 100 μm, for example. This can improve the battery capacity of the solid state battery 1.

[0052] 5, an insulating frame 6 may be provided on the outer periphery of the positive electrode active material layer 31. The insulating frame 6 can prevent short-circuiting of the solid state battery 1 and improve the strength. The insulating frame 6 is arranged so as to cover the side surfaces of the two positive electrode active material layers 31 formed on both sides of the positive electrode current collector layer 32 when the solid state battery 1 is completed. The material constituting the insulating frame 6 is not particularly limited, but examples thereof include insulating oxides such as alumina, resins such as polyvinylidene fluoride (PVDF), and rubbers such as styrene-butadiene rubber (SBR).

[0053] The positive electrode current collector layer 32 is not particularly limited, and may be made of, for example, aluminum, stainless steel, conductive carbon (graphite, carbon nanotubes, etc.), etc. Examples of the shape of the positive electrode current collector layer 32 include foil, plate, mesh, nonwoven fabric, and foam. In this embodiment, the positive electrode current collector layer 32 is made of a positive electrode current collector foil 321.

[0054] (Intermediate Layer) The intermediate layer 5 is disposed between the anode layer 2 and the solid electrolyte layer 4. For example, when the solid 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 4 is stabilized. When the solid battery 1 is a lithium metal secondary battery having the intermediate layer 5, the solid battery 1 may be an anode-free battery in which the anode active material layer 21 is not present during the initial charge. In this case, a lithium metal layer is formed as the anode active material layer 21 after the initial charge / discharge.

[0055] The material constituting the intermediate layer 5 is not particularly limited, but examples thereof include metals capable of alloying with lithium and amorphous carbon. Examples of metals capable of alloying with lithium include tin (Sn), silicon (Si), zinc (Zn), magnesium (Mg), gold (Au), platinum (Pt), palladium (Pd), silver (Ag), aluminum (Al), bismuth (Bi), and antimony (Sb). The metal capable of alloying with lithium may be nanoparticles. Examples of amorphous carbon include carbon blacks such as acetylene black, furnace black, and ketjen black, coke, and activated carbon. The amorphous carbon may be easily graphitized carbon (soft carbon), difficult-to-graphitize carbon (hard carbon), CNT (carbon nanotube), fullerene, or graphene. The intermediate layer may contain a binder in addition to the above materials.

[0056] A manufacturing system 100 for manufacturing the above-described solid-state battery 1 will now be described. FIG. 2 shows the manufacturing system 100 for the solid-state battery 1 of this embodiment. The manufacturing system 100 includes a first positive electrode transfer roller 310, a second positive electrode transfer roller 320, an intermediate layer transfer roller 370 (see FIG. 3), a negative electrode transfer roller 330 (see FIG. 3), a negative electrode sheet member lamination roller 340, a positive electrode press device 350, and an integration press device 360. The positive electrode sheet member 300 is fed in one direction by each of the rollers, thereby continuously manufacturing the solid-state battery 1. Note that FIG. 1 shows the areas that are pressed or transfer-pressed in the positive electrode press step S3, the second solid electrolyte layer transfer step S4, the intermediate layer transfer step S5, the negative electrode solid electrolyte layer transfer step S6, and the integration press step S9, which will be described later.

[0057] The positive electrode side sheet member 300 is a sheet-like member obtained by laminating the positive electrode active material layer 31 on the positive electrode current collector foil 321 that constitutes the positive electrode current collector layer 32. The positive electrode side sheet member 300 is fed by rollers (not shown) and conveyed so as to extend continuously from the base end to the terminal end of the production line for the solid state battery 1.

[0058] The first positive transfer roller 310, the second positive transfer roller 320, the intermediate layer transfer roller 370, the negative transfer roller 330, and the negative sheet member laminating roller 340 each comprise a pair of rotating rollers. The first positive transfer roller 310, the second positive transfer roller 320, the intermediate layer transfer roller 370, and the negative transfer roller 330 perform transfer pressing by sandwiching a sheet such as a substrate to be transferred and a sheet provided with a solid electrolyte layer to be transferred between the pair of rollers and passing them while applying pressure. The negative sheet member laminating roller 340 positions the sandwiched sheet as it passes.

[0059] The positive electrode press device 350 and the integration press device 360 ​​are each composed of a pair of rotating rollers, similar to the transfer roller, and are devices that sandwich the positive electrode side sheet member 300, on which a solid electrolyte layer or the like is laminated depending on the process, between the pair of rollers and pass it through while applying pressure, thereby densifying the positive electrode side sheet member 300.

[0060] 2 , these rollers are arranged in the following order from upstream along the feeding direction of the positive electrode side sheet member 300: the first positive electrode side transfer roller 310, the positive electrode press device 350, the second positive electrode side transfer roller 320, the negative electrode side sheet member laminating roller 340, and the integration press device 360. When the solid state battery 1 has a second solid electrolyte layer SE2, the second positive electrode side transfer roller 320 is disposed between the positive electrode press device 350 and the negative electrode side sheet member laminating roller 340.

[0061] The intermediate layer transfer roller 370 and the negative electrode side transfer roller 330 are positioned away from the delivery line L of the positive electrode side sheet member 300, and perform transfer pressing of the intermediate layer 5 or the negative electrode side solid electrolyte layer SE3. Thereafter, as will be described later, the formed intermediate layer 5 and negative electrode layer 2 are conveyed to the upper or lower surface side of the positive electrode side sheet member 300, merge with the delivery line L of the positive electrode side sheet member 300, and are laminated by the negative electrode side sheet member lamination roller 340.

[0062] A description will now be given of a method for manufacturing the solid-state battery 1 using the above-described manufacturing system 100 for the solid-state battery 1. First, the positive electrode-side sheet member 300, which is formed by coating and laminating a positive electrode active material on the positive electrode current collector foil 321 constituting the positive electrode current collector layer 32, is conveyed and fed by conveying rollers (not shown) (positive electrode-side sheet member feeding step S1).

[0063] As shown in FIG. 5, the positive electrode side sheet member 300 has an insulating frame 6 formed on the positive electrode current collector foil 321 along the design dimensions of the solid state battery 1 after completion.

[0064] Next, the first solid electrolyte layer SE1 is transferred to the positive electrode side sheet member 300 by the first positive electrode side transfer roller 310 (first solid electrolyte layer transfer step S2). The first solid electrolyte layer transfer step S2 includes an alignment step S21 and a transfer press step S22. In the alignment step S21, the first solid electrolyte layer SE1 is aligned on the positive electrode side sheet member 300 so that it is positioned within a range guided by a guide roller (not shown). In the transfer press step S22, the slurry constituting the first solid electrolyte layer SE1 is passed over the positive electrode side sheet member 300 while being pressed by the first positive electrode side transfer roller 310, which serves as a transfer roller, to perform transfer press. The pressure at this time can be, for example, 50 to 500 MPa at room temperature (e.g., 10 to 35°C). Preferably, it may be 100 MPa at 25°C.

[0065] Next, the cathode side sheet member 300 onto which the first solid electrolyte layer SE1 has been transferred is pressed by a cathode press device 350 (cathode press step S3). This cathode press step S3 densifies the cathode. To achieve densification, the press pressure is approximately 800 to 1200 MPa at 25 to 100°C. The densified stack of the cathode side sheet member 300 and the first solid electrolyte layer SE1 is transported downstream along the delivery line L.

[0066] After the positive electrode pressing step S3, the second positive electrode transfer roller 320 transfers the second solid electrolyte layer SE2 onto the positive electrode sheet member 300 onto which the first solid electrolyte layer SE1 has been transferred and pressed (second solid electrolyte layer transfer step S4). The second solid electrolyte layer transfer step S4 includes an alignment step S41 and a transfer press step S42. In the alignment step S41, the second solid electrolyte layer SE2 is aligned on the positive electrode sheet member 300 onto which the first solid electrolyte layer SE1 has been transferred so that it is positioned within a range guided by a guide roller (not shown). In the transfer press step S42, the slurry constituting the second solid electrolyte layer SE2 is passed over the positive electrode sheet member 300 while being pressed by the second positive electrode transfer roller 320 as a transfer roller, thereby performing transfer press. The pressure at this time can be 50 to 500 MPa at room temperature (e.g., 10 to 35°C). In this way, the positive electrode side sheet member 300 is pressed two or more times, including the transfer step and the pressing step. Preferably, the pressure may be 150 MPa at 25°C.

[0067] Meanwhile, a negative electrode-side sheet member 400 is prepared at a position away from the delivery line L. First, as shown in the upper part of FIG. 3 , an intermediate layer 5 is transferred by an intermediate layer transfer roller 370 to the negative electrode active material layer 21 stacked on the negative electrode current collector foil 221 (intermediate layer transfer step S5). Then, as shown in the lower part of FIG. 3 , an negative electrode-side solid electrolyte layer SE3 is transferred onto the intermediate layer 5 by an negative electrode-side transfer roller 330 to form the negative electrode-side sheet member 400 (negative electrode-side solid electrolyte layer transfer step S6). Through this procedure, the intermediate layer 5 is disposed between the negative electrode active material layer 21 and the negative electrode-side solid electrolyte layer SE3. In this embodiment, the negative electrode-side sheet member 400 includes a stack of the negative electrode current collector foil 221, the negative electrode active material layer 21, the intermediate layer 5, and the negative electrode-side solid electrolyte layer SE3, but the negative electrode active material layer 21 and the intermediate layer 5 may not be included.

[0068] The intermediate layer transfer step S5 includes an intermediate layer positioning step S51 and an intermediate layer transfer press step S52. In the intermediate layer positioning step S51, the slurry constituting the intermediate layer 5 is positioned on the negative electrode active material layer 21 so as to be disposed within a range guided by a guide roller (not shown). In the intermediate layer transfer press step S52, the intermediate layer 5 is passed over the negative electrode active material layer 21 while being pressed by an intermediate layer transfer roller 370 serving as a transfer roller, thereby performing intermediate layer transfer press, in which the intermediate layer 5 is transferred to the negative electrode active material layer 21. The pressure at this time can be 50 to 800 MPa at room temperature (e.g., 10 to 35°C), and more preferably, is in the range of 300 MPa or more and 800 MPa or less at 25°C.

[0069] The anode-side solid electrolyte layer transfer step S6 includes an anode-side solid electrolyte layer positioning step S61 and an anode-side solid electrolyte layer transfer press step S62. In the anode-side solid electrolyte layer positioning step S61, the slurry constituting the anode-side solid electrolyte layer SE3 is positioned on the intermediate layer 5 so as to be disposed within a range guided by a guide roller (not shown). In the anode-side solid electrolyte layer transfer press step S62, the anode-side solid electrolyte layer SE3 is passed over the intermediate layer 5 while being pressed by an anode-side transfer roller 330 serving as a transfer roller, thereby performing anode active material layer transfer press, in which the anode-side solid electrolyte layer SE3 is transferred to the intermediate layer 5. The pressure at this time can be 600 to 800 MPa at room temperature (e.g., 10 to 35°C).

[0070] Regarding pressure, the pressing pressure in the positive electrode pressing step S3 is not only the maximum pressure applied to the positive electrode sheet member 300 but also the maximum pressure applied in the entire manufacturing method of the solid state battery 1. The positive electrode sheet member 300 is pressed at high pressure to increase the energy density and densify the electrode. The maximum pressing pressure in the positive electrode pressing step S3 is equal to or greater than the maximum pressing pressure applied to the negative electrode sheet member 400. Furthermore, the pressure applied during the transfer in the first solid electrolyte layer transfer step S2 and the second solid electrolyte layer transfer step S4 is lower than the pressing pressure in the positive electrode pressing step S3. Furthermore, the pressure applied during the transfer in the first solid electrolyte layer transfer step S2 and the second solid electrolyte layer transfer step S4 is lower than the pressing pressure in the negative electrode solid electrolyte layer transfer step S6. 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 press pressure as low as possible, it is possible to reduce the amount of extension of the first solid electrolyte layer SE1 and the second solid electrolyte layer SE2 due to the transfer press. Therefore, room for extension of the first solid electrolyte layer SE1 and the second solid electrolyte layer SE2 can be left in the subsequent integration press step S9, etc., and the first solid electrolyte layer SE1 can be extended while following the positive electrode layer 3. This improves the bonding strength of the first solid electrolyte layer SE1 to the positive electrode active material layer 31.

[0071] After the anode-side solid electrolyte layer transfer step S6, the formed anode-side sheet member 400 is cut with a cutter while being supported by a payout roll that pays out the member to be transferred in the anode-side solid electrolyte layer transfer step S6 (anode-side sheet member cutting step S7). The anode-side sheet member 400 is cut to the design dimensions of the anode layer 2 of the solid-state battery 1. As shown in Fig. 5, the anode-side sheet member 400 is cut to a size slightly smaller than the size to which the cathode-side sheet member 300 is cut in the cutting step S10, which will be described later, in order to prevent short circuits.

[0072] As shown in FIGS. 2 and 4 , the negative electrode-side sheet member 400 cut to the design dimensions is conveyed to the positive electrode-side sheet member 300 so as to merge with the delivery line L of the positive electrode-side sheet member 300, and is laminated on the positive electrode-side sheet member 300. At this time, prior to the integration press step S9 described below, a first solid electrolyte layer SE1 and a second solid electrolyte layer SE2 are provided on the lower layer side of the surface of the positive electrode-side sheet member 300 facing the negative electrode-side solid electrolyte layer SE3. The negative electrode-side sheet member 400 is then placed on top of the first solid electrolyte layer SE1 and the second solid electrolyte layer SE2 in a cut state on the positive electrode-side sheet member 300. Specifically, the negative electrode-side sheet member 400 onto which the negative electrode-side solid electrolyte layer SE3 has been transferred is conveyed and laminated by the negative electrode-side sheet member lamination roller 340 on top of the positive electrode-side sheet member 300 onto which the first solid electrolyte layer SE1 and the second solid electrolyte layer SE2 have been transferred (negative electrode-side sheet member lamination step S8). In laminating the negative electrode side sheet member, the negative electrode side sheet member 400 cut to the design dimensions is aligned on the positive electrode side sheet member 300 onto which the first solid electrolyte layer SE1 and the second solid electrolyte layer SE2 have been transferred so that it is positioned within a range guided by a guide roller (not shown).

[0073] In this stacked state, the cathode-side sheet member 300 and the anode-side sheet member 400 are pressed by an integration press device 360 ​​to integrate the electrode 10 (integration press step S9). With respect to the thickness of the anode-side sheet member 400 and the cathode-side sheet member 300 in the stacking direction immediately before the integration press step S9, the thickness of the cathode-side sheet member 300 is greater than the thickness of the anode-side sheet member 400. The pressure at this time is, for example, approximately 500 to 900 MPa at 25 to 100°C. The integration press step S9 integrates the cathode-side sheet member 300 and the anode-side sheet member 400, while simultaneously densifying the first solid electrolyte layer SE1, the second solid electrolyte layer SE2, and the anode-side solid electrolyte layer SE3. Comparing the press pressures in the integration press step S9 and the cathode press step S3, the press pressure in the cathode press step S3 is greater than the press pressure in the integration press step S9.

[0074] After the integration pressing step S9, the formed electrode 10 is cut with a rotary cutter (cutting step S10).

[0075] 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 member 300 in the positive electrode pressing step S3, the transfer of the second solid electrolyte layer SE2 in the second solid electrolyte layer transfer step S4, the lamination of the negative electrode side sheet member 400 before integration in the negative electrode side sheet member lamination step S8, and the integration pressing in the integration press step S9 are performed on both sides of the positive electrode side sheet member 300 delivered in the positive electrode side sheet member delivery step S1. This results in a solid state battery 1 in which the layers are symmetrically stacked on both the top and bottom surfaces, as shown in FIG. 1 .

[0076] As described above, the first solid electrolyte layer transfer step S2, the second solid electrolyte layer transfer step S4, the positive electrode pressing step S3, the negative electrode sheet member lamination step S8, and the integration pressing step S9 are continuously performed on the positive electrode sheet member 300 fed in the positive electrode sheet member feeding step S1. The negative electrode sheet member forming step S40 is performed at a position separated from the positive electrode sheet member 300, but the formed negative electrode sheet member 400 is positioned to merge with the positive electrode sheet member 300, and the manufacturing method for the solid state battery 1 is performed in a continuous series of steps.

[0077] The present embodiment provides the following advantages: (1) A method for manufacturing a solid-state battery 1 includes a cathode-side sheet member feeding step S1 of feeding out a cathode-side sheet member 300 having a cathode active material layer 31 laminated on a cathode current collector foil 321, a first solid electrolyte layer transferring step S2 of transferring a first solid electrolyte layer SE1 to the cathode-side sheet member 300, a cathode pressing step S3 of pressing the cathode-side sheet member 300 to which the first solid electrolyte layer SE1 has been transferred, and a cathode pressing step S4 of pressing the cathode-side sheet member 300 to which the first solid electrolyte layer SE1 has been transferred onto the anode active material layer 21 laminated on the anode current collector foil 221. The method includes an anode-side solid electrolyte layer transfer step S6 of transferring the first solid electrolyte layer SE3 to form the anode-side sheet member 400, an anode-side sheet member lamination step S8 of laminating the anode-side sheet member 400 to which the anode-side solid electrolyte layer SE3 has been transferred on the cathode-side sheet member 300 to which at least the first solid electrolyte layer SE1 has been transferred, and an integration press step S9 of pressing the stacked cathode-side sheet member 300 and the anode-side sheet member 400 to integrate the electrodes. The first solid electrolyte layer transfer step S2, the cathode press step S3, the anode-side sheet member lamination step S8, and the integration press step S9 are successively performed on the cathode-side sheet member 300. The solid state battery 1 having a plurality of solid electrolyte layers, such as the first solid electrolyte layer SE1 and the anode-side solid electrolyte layer SE3, is manufactured by continuously transferring and pressing the layers onto the cathode-side sheet member 300. This makes it possible to manufacture the solid state battery 1 continuously and with high productivity while optimizing the adhesion and interface formation of each layer.

[0078] (2) According to this embodiment, the method further includes a second solid electrolyte layer transfer step S4 of transferring the second solid electrolyte layer SE2 onto the pressed cathode-side sheet member 300 after the cathode pressing step S3. The anode-side sheet member lamination step S8 is configured to laminate the anode-side sheet member 400, onto which the anode-side solid electrolyte layer SE3 has been transferred, on the cathode-side sheet member 300, onto which the second solid electrolyte layer SE2 has been transferred. This enables the solid battery 1 including three layers, the first solid electrolyte layer SE1, the second solid electrolyte layer SE2, and the anode-side solid electrolyte layer SE3, to be manufactured with high productivity. Furthermore, by performing the transfer at different temperatures and pressures in the first solid electrolyte layer transfer step S2 and the second solid electrolyte layer transfer step S4, the cathode-side sheet member 300 can be continuously fed out while being manufactured in an optimal environment and under optimal conditions for each solid electrolyte layer.

[0079] (3) According to this embodiment, the thickness of the first solid electrolyte layer SE1 and the thickness of the anode-side solid electrolyte layer SE3 are configured to be thinner than the thickness of the second solid electrolyte layer SE2. This facilitates the first solid electrolyte layer SE1 to conform to and adhere to the cathode layer 3, and the anode-side solid electrolyte layer SE3 to the anode layer 2, while also facilitating stable bonding between the two by the second solid electrolyte layer SE2. Furthermore, solid electrolyte layers having different thicknesses can be continuously manufactured in an optimal environment and under optimal conditions.

[0080] (4) According to this embodiment, the method further includes an intermediate layer transfer step S5 of transferring an intermediate layer 5 onto the anode active material layer 21. In the anode-side solid electrolyte layer transfer step S6, the anode-side sheet member 400 is formed by transferring the anode-side solid electrolyte layer SE3 onto the intermediate layer 5. The intermediate layer 5 is disposed between the anode active material layer 21 and the anode-side solid electrolyte layer SE3. By providing the intermediate layer 5, when the solid battery 1 is a lithium metal battery, it becomes possible to uniformly deposit lithium metal and stabilize the interface between the intermediate layer 5 and the solid electrolyte layer 4.

[0081] (5) According to this embodiment, the cutting step S10 of cutting the formed electrode is further included after the integration pressing step S9. This allows a plurality of electrodes 10 to be obtained from a laminate in which the negative electrode layer 2 and each solid electrolyte layer are laminated on the positive electrode side sheet member 300, thereby improving productivity.

[0082] (6) According to this embodiment, the method further includes a negative electrode-side sheet member cutting step S7 of cutting the negative electrode-side sheet member 400 after the negative electrode-side solid electrolyte layer transfer step S6. The negative electrode-side sheet member 400 is laminated on the positive electrode-side sheet member 300 in a cut state. The negative electrode-side sheet member 400 may be softer than the positive electrode-side sheet member 300. In this case, cutting the negative electrode-side sheet member and laminating it on the positive electrode-side sheet member 300 in a cut state enables more precise control of the dimensions of the negative electrode layer 2. This allows for continuous, highly productive production of solid state batteries 1.

[0083] (7) According to this embodiment, the pressure applied during the transfer in the first solid electrolyte layer transfer step S2 and the second solid electrolyte layer transfer step S4 is set to be lower than the pressing pressure applied in the positive electrode pressing step S3. This allows the first solid electrolyte layer SE1 and the second solid electrolyte layer SE2 to be transferred with a necessary and suitable pressure, and also makes it possible to make the positive electrode layer 3 dense and increase the energy density. This makes it possible to continuously manufacture solid state batteries 1 having multiple layers by pressing them with a pressure required for the attributes of each layer.

[0084] (8) According to this embodiment, the pressure applied during the transfer in the first solid electrolyte layer transfer step S2 and the second solid electrolyte layer transfer step S4 is set to be lower than the pressure applied during the transfer in the anode-side solid electrolyte layer transfer step S6. When the target to which the anode-side solid electrolyte layer SE3 is to be transferred (the intermediate layer 5 if the solid-state battery 1 includes the intermediate layer 5) does not contain a binder, it is preferable to transfer the anode-side solid electrolyte layer SE3 with a relatively strong pressure. In this way, the anode-side solid electrolyte layer SE3 can be transferred with a necessary and appropriate pressure.

[0085] (9) According to this embodiment, the pressing pressure in the positive electrode pressing step S3 is set to be greater than the pressing pressure in the integration pressing step S9. The positive electrode layer 3 requires a high pressure to be highly densified. On the other hand, once the positive electrode side sheet member 300 is pressed, and the second solid electrolyte layer SE2, the negative electrode side solid electrolyte layer SE3, and the like are laminated on the positive electrode side sheet member 300, the layers are stably integrated without applying the pressing pressure up to the positive electrode pressing step S3. Therefore, it is possible to continuously manufacture the solid state batteries 1 while pressing the solid state batteries 1 with the pressure required for the attributes of each layer.

[0086] (10) According to this embodiment, 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 member 300 in the positive electrode pressing step S3, the lamination of the negative electrode side sheet member 400 in the negative electrode side sheet member lamination step S8, and the integration pressing in the integration pressing step S9 are performed on both sides of the positive electrode side sheet member 300 delivered in the positive electrode side sheet member delivery step S1. This makes it possible to obtain a solid battery 1 in which the solid electrolyte layer and the negative electrode layer 2 are symmetrically formed on both sides of the positive electrode side sheet member 300.

[0087] (11) According to this embodiment, the first solid electrolyte layer transferring step S2 and the second solid electrolyte layer transferring step S4 are configured to include positioning steps S21 and S41 of aligning the first solid electrolyte layer SE1 and the second solid electrolyte layer SE2, respectively, on the positive electrode-side sheet member 300, and transfer pressing steps S22 and S42 of transferring and pressing the first and second positive electrode-side transfer rollers 310 and 320. By including the positioning steps S21 and S41 and the transfer pressing steps S22 and S42 in the respective transfer steps S2 and S4, it is possible to more accurately control the transfer position.

[0088] (12) According to this embodiment, the intermediate layer transferring step S5 includes an intermediate layer positioning step S51 of aligning the intermediate layer 5 on the anode active material layer 21, and an intermediate layer transfer press step S52 of transferring and pressing the intermediate layer 5 to the anode active material layer 21 with the intermediate layer transfer roller 370. The anode-side solid electrolyte layer transferring step S6 includes an anode-side solid electrolyte layer positioning step S61 of aligning the anode-side solid electrolyte layer SE3 on the intermediate layer 5 transferred to the anode active material layer 21, and an anode-side solid electrolyte layer transfer press step S62 of transferring and pressing the anode-side solid electrolyte layer SE3 to the intermediate layer 5 with the anode-side transfer roller 330. This makes it possible to more accurately control the transfer positions in the intermediate layer transferring step S5 and the anode-side solid electrolyte layer transferring step S6.

[0089] (13) According to this embodiment, the solid-state battery manufacturing system 100 includes a first positive-side transfer roller 310 that transfers the first solid electrolyte layer SE1 to the positive-side sheet member 300 having the positive-side current collector foil 321 and the positive-side active material layer 31 laminated thereon, a positive-side press device 350 that presses the positive-side sheet member 300 having the first solid electrolyte layer SE1 transferred thereon, and a negative-side transfer device 350 that transfers the negative-side solid electrolyte layer SE3 to the negative-side active material layer 21 laminated thereon. The apparatus includes a negative electrode-side transfer roller 330 that forms the positive electrode-side sheet member 400, a negative electrode-side sheet member lamination roller 340 that laminates the negative electrode-side sheet member 400, onto which the negative electrode-side solid electrolyte layer SE3 has been transferred, on the positive electrode-side sheet member 300, onto which at least the first solid electrolyte layer SE1 has been transferred, and an integration press device 360 ​​that presses the positive electrode-side sheet member 300 and the negative electrode-side sheet member 400 in a stacked state so as to integrate the electrodes. The first positive electrode-side transfer roller 310, the positive electrode press device 350, the negative electrode-side sheet member lamination roller 340, and the integration press device 360 ​​are arranged in this order from the upstream side along the feeding direction of the positive electrode-side sheet member 300. As a result, the solid battery 1 having a plurality of solid electrolyte layers, such as the first solid electrolyte layer SE1 and the anode-side solid electrolyte layer SE3, is manufactured by continuously transferring and pressing the layers onto the cathode-side sheet member 300, which makes it possible to manufacture the solid battery 1 continuously and with good productivity while optimizing the adhesion and interface formation of each layer.

[0090] The present invention is not limited to the above embodiment, and modifications, improvements, etc., within the scope that can achieve the object of the present invention are included in the present invention. In the above embodiment, the second solid electrolyte layer SE2 is laminated and transferred between the anode-side solid electrolyte layer SE3 and the first solid electrolyte layer SE1 before the integration press step S9. In addition, the intermediate layer 5 is transferred to the anode active material layer 21 laminated on the anode current collector foil 221. However, the second solid electrolyte layer SE2 and the intermediate layer 5 may not be included. In addition, the anode-side sheet member 400 may not include the anode active material layer 21.

[0091] REFERENCE SIGNS LIST 1 Solid-state battery 5 Intermediate layer 10 Electrode 21 Negative electrode active material layer 31 Positive electrode active material layer SE1 First solid electrolyte layer SE2 Second solid electrolyte layer SE3 Negative electrode side solid electrolyte layer 221 Negative electrode current collector foil 100 Manufacturing system 300 Positive electrode side sheet member 400 Negative electrode side sheet member 321 Positive electrode current collector foil 310 First positive electrode side transfer roller (transfer roller) 330 Negative electrode side transfer roller (transfer roller) 340 Negative electrode side sheet member laminating roller 350 Positive electrode press device 360 ​​Integration press device S1 Positive electrode side sheet member feeding step S2 First solid electrolyte layer transfer step S3 Positive electrode press 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 member cutting step S8 Negative electrode side sheet member stacking step S9 Integration pressing step S10 Cutting step

Claims

1. A method for manufacturing a sheet member, comprising: a cathode-side sheet member feeding step of feeding out a cathode-side sheet member having a cathode active material layer laminated on a cathode current collector foil; a first solid electrolyte layer transferring step of transferring a first solid electrolyte layer onto the cathode-side sheet member; a cathode pressing step of pressing the cathode-side sheet member onto which the first solid electrolyte layer has been transferred; an anode-side solid electrolyte layer transferring step of transferring an anode-side solid electrolyte layer onto an anode active material layer laminated on an anode current collector foil to form an anode-side sheet member; an anode-side sheet member laminating step of laminating the anode-side sheet member onto which the anode-side solid electrolyte layer has been transferred on at least the cathode-side sheet member onto which the first solid electrolyte layer has been transferred; and an integration pressing step of pressing the cathode-side sheet member and the anode-side sheet member, which are laminated together, to integrate the electrodes. the first solid electrolyte layer transferring step, the positive electrode pressing step, the negative electrode side sheet member laminating step, and the integration pressing step are performed consecutively on the positive electrode side sheet member.

2. The method for manufacturing a solid-state battery according to claim 1, further comprising a second solid electrolyte layer transfer step of transferring a second solid electrolyte layer onto the pressed positive electrode sheet member after the positive electrode pressing step, wherein the negative electrode sheet member laminating step involves laminating the negative electrode sheet member onto which the negative electrode solid electrolyte layer has been transferred, on top of the positive electrode sheet member onto which the second solid electrolyte layer has been transferred.

3. The method for manufacturing a solid-state battery according to claim 2, wherein the thickness of the first solid electrolyte layer and the thickness of the negative electrode side solid electrolyte layer are thinner than the thickness of the second solid electrolyte layer.

4. The method for manufacturing a solid-state battery according to claim 1, further comprising an intermediate layer transfer step of transferring an intermediate layer onto the anode active material layer, wherein the anode-side solid electrolyte layer transfer step forms the anode-side sheet member by transferring the anode-side solid electrolyte layer onto the intermediate layer, and the intermediate layer is disposed between the anode active material layer and the anode-side solid electrolyte layer.

5. The method for producing a solid-state battery according to claim 1, further comprising a cutting step of cutting the formed electrodes after the integral pressing step.

6. The method for manufacturing a solid-state battery according to claim 1, further comprising a step of cutting the negative electrode sheet member after the negative electrode solid electrolyte layer transfer step, wherein the negative electrode sheet member is laminated on the positive electrode sheet member in a cut state.

7. The method for manufacturing a solid-state battery according to claim 2, wherein the pressure applied during the first solid electrolyte layer transfer step and the second solid electrolyte layer transfer step is lower than the pressing pressure applied during the positive electrode pressing step.

8. The method for manufacturing a solid-state battery according to claim 2, wherein the pressure during the transfer in the first solid electrolyte layer transfer step and the second solid electrolyte layer transfer step is lower than the pressure during the transfer in the negative electrode solid electrolyte layer transfer step.

9. The method for manufacturing a solid-state battery according to claim 1, wherein the pressing pressure in the positive electrode pressing step is greater than the pressing pressure in the integration pressing step.

10. A method for manufacturing a solid state battery as described in claim 1, wherein the transfer of the first solid electrolyte layer in the first solid electrolyte layer transfer step, the pressing of the positive electrode side sheet member in the positive electrode pressing step, the lamination of the negative electrode side sheet member in the negative electrode side sheet member lamination step, and the integration pressing in the integration pressing step are performed on both sides of the positive electrode side sheet member fed in the positive electrode side sheet member feeding step.

11. The method for manufacturing a solid state battery according to claim 2, wherein the first solid electrolyte layer transfer step and the second solid electrolyte layer transfer step include an alignment step of aligning the first solid electrolyte layer and the second solid electrolyte layer on the positive electrode side sheet member, respectively, and a transfer press step of transferring and pressing the layers using a transfer roller.

12. A method for manufacturing a solid state battery according to claim 4, wherein the intermediate layer transferring step comprises: an intermediate layer positioning step of aligning the intermediate layer on the negative electrode active material layer; and an intermediate layer transfer pressing step of transfer-pressing the intermediate layer onto the negative electrode active material layer with an intermediate layer transfer roller; and the negative electrode side solid electrolyte layer transferring step comprises: an anode side solid electrolyte layer positioning step of aligning the anode side solid electrolyte layer on the intermediate layer transferred onto the negative electrode active material layer; and an anode side solid electrolyte layer transfer pressing step of transfer-pressing the anode side solid electrolyte layer onto the intermediate layer with an anode side transfer roller.

13. A solid-state battery manufacturing system comprising: a first positive electrode transfer roller that transfers a first solid electrolyte layer onto a positive electrode sheet member having a positive electrode active material layer laminated on a positive electrode current collector foil; a positive electrode press device that presses the positive electrode sheet member onto which the first solid electrolyte layer has been transferred; a negative electrode transfer roller that transfers a negative electrode solid electrolyte layer onto a negative electrode active material layer laminated on a negative electrode current collector foil to form a negative electrode sheet member; a negative electrode sheet member laminating roller that laminates the negative electrode sheet member having the negative electrode solid electrolyte layer laminated on the positive electrode sheet member onto which at least the first solid electrolyte layer has been transferred; and an integrating press device that presses the positive electrode sheet member and the negative electrode sheet member in a laminated state to integrate the electrodes, wherein the first positive electrode transfer roller, the positive electrode press device, the negative electrode sheet member laminating roller, and the integrating press device are arranged in order from upstream along the feeding direction of the positive electrode sheet member.

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