JP7566498B2 - Roll of battery element, method for producing same, and all-solid-state battery including said roll - Google Patents

Description

The present invention relates to a roll of battery elements for use in an all-solid-state battery, a method for producing the same, and an all-solid-state battery using such a roll.

An all-solid-state battery includes a positive electrode, a negative electrode, and a solid electrolyte layer. For example, a positive electrode active material layer, a solid electrolyte layer, a negative electrode active material layer, and a negative electrode current collector are stacked in this order on a positive electrode current collector. For example, an all-solid-state battery that uses lithium cobalt oxide (LiCoO2) as the positive electrode active material, lithium phosphate oxynitride (LiPON) as the solid electrolyte, and metallic lithium as the negative electrode active material has been put to practical use.

Patent Document 1 describes that an all-solid-state battery can be obtained by appropriately stacking a first green sheet for forming a positive electrode, a second green sheet for forming a negative electrode, and a third green sheet for forming a solid electrolyte layer, and sintering the resulting laminate.

Patent document 2 describes a process in which a positive electrode active material layer and a positive electrode current collector layer are formed on a temporary substrate, and then the temporary substrate is separated to expose the positive electrode active material layer, on which a solid electrolyte layer and a negative electrode current collector layer are formed.

Patent document 3 discloses a method for manufacturing an all-solid-state battery having a battery element with a structure in which an electrode layer and a solid electrolyte layer are laminated, characterized in that the battery element is sealed with a sealing layer containing a crystalline ceramic that is fired together with at least a part of the structure.

JP 2019-149374 A JP 2016-001599 A JP 2016-167356 A

The present invention aims to provide a roll of battery elements that allows for easier mass production of all-solid-state batteries compared to conventional techniques, a method for producing the same, and an all-solid-state battery that uses such a roll.

The present invention is a rolled battery element in which a negative electrode sheet, in which a negative electrode collector layer and a negative electrode active material layer are provided in this order on a first long resin sheet, and a positive electrode sheet, in which a positive electrode collector layer and a positive electrode active material layer are provided in this order on a second long resin sheet, are wound in opposing relation such that a solid electrolyte layer is further provided on at least one of the negative electrode active material layer and the positive electrode active material layer, and the solid electrolyte layer is sandwiched between the negative electrode active material layer and the positive electrode active material layer.

In the roll of the battery element according to the present invention, the negative electrode sheet and the positive electrode sheet are wound so that the surface of the first long resin sheet on which the negative electrode current collector layer and the negative electrode active material layer are provided faces the surface of the second long resin sheet on which the positive electrode current collector layer and the positive electrode active material layer are provided, and the solid electrolyte layer is sandwiched between the negative electrode active material layer and the positive electrode active material layer. Therefore, the area sandwiched between the resin sheets of the negative electrode sheet and the positive electrode sheet has a laminated structure in which the negative electrode current collector layer, the negative electrode active material layer, the solid electrolyte layer, the positive electrode active material layer, and the positive electrode current collector layer are laminated in sequence, and this laminated structure is electrically insulated by the resin sheet to form a roll of the battery element wound in large numbers.

In the roll body according to the present invention, the outermost and innermost circumferential surfaces of the roll body can be covered with an insulating protective film.
It is not preferable that the solid electrolyte layer is exposed on the outermost and innermost circumferential surfaces of the roll body, as this reduces the ion conductivity, etc. Although it is possible to cover the solid electrolyte layer with a battery case such as a laminate film, it is preferable to cover the solid electrolyte layer directly with an insulating protective film.

In the roll body according to the present invention, a negative electrode current collector exposed portion where the negative electrode current collector layer is exposed, and a positive electrode current collector exposed portion where the positive electrode current collector layer is exposed can be provided on at least a part of the roll body, typically on the outermost peripheral surface and the innermost peripheral surface.
In this case, by connecting a negative electrode lead to the exposed portion of the negative electrode current collector and a positive electrode lead to the exposed portion of the positive electrode current collector, electrical connection with other electric components and the like can be achieved.
The all-solid-state battery according to the present invention can be an all-solid-state battery in which the roll body is housed in a battery case.

The present invention includes a process for preparing a negative electrode roll-shaped original sheet by winding a negative electrode sheet having a negative electrode current collector layer and a negative electrode active material layer provided in this order on a wide and long first resin sheet, and a process for preparing a positive electrode roll-shaped original sheet by winding a positive electrode sheet having a positive electrode current collector layer and a positive electrode active material layer provided in this order on a wide and long second resin sheet, and a solid electrolyte layer is further provided on at least one of the negative electrode active material layer and the positive electrode active material layer, and the negative electrode sheet unwound from the negative electrode roll-shaped original sheet and the positive electrode sheet unwound from the positive electrode roll-shaped original sheet are arranged such that the first surface of the first resin sheet and the first surface of the second resin sheet face each other. The method for manufacturing a roll of a battery element includes a slitting step of slitting the first resin sheet and the positive electrode sheet into a plurality of narrow-width sheets in a state in which the negative electrode sheet and the positive electrode sheet are overlapped, or the surface opposite to the first surface of the first resin sheet (i.e., the surface of the two surfaces of the first resin sheet on which the negative electrode current collector layer is not provided) and the surface opposite to the first surface of the second resin sheet (i.e., the surface of the two surfaces of the second resin sheet on which the positive electrode current collector layer is not provided) face each other, and further includes a winding step of winding up each of the plurality of narrow-width sheets into a roll of a battery element.

The manufacturing method of the present invention makes it possible to efficiently mass-produce rolls of battery elements of any size, in which a laminate structure in which a negative electrode collector layer, a negative electrode active material layer, a solid electrolyte layer, a positive electrode active material layer, and a positive electrode collector layer are sequentially laminated with a resin sheet interposed therebetween, is wound in large numbers.

In the manufacturing method of the present invention, in the slitting process, the negative electrode sheet unwound from the negative electrode roll and the positive electrode sheet unwound from the positive electrode roll are overlapped and cut into the multiple narrow-width sheets by a slitter head, and in the winding process, when the narrow-width sheet has been wound up a predetermined number of times or to a predetermined diameter, the end of the winding can be cut.
This makes it possible to manufacture a roll of battery elements for an all-solid-state battery that matches any battery capacity.

In the manufacturing method of the present invention, the step of preparing the negative electrode roll-shaped original sheet may include coating the negative electrode current collector layer and the negative electrode active material layer in this order on the wide and long first resin sheet, and the step of preparing the positive electrode roll-shaped original sheet may include coating the positive electrode current collector layer and the positive electrode active material layer in this order on the wide and long second resin sheet, and further coating the solid electrolyte layer on at least one of the negative electrode active material layer and the positive electrode active material layer.
In the coating method, the paste (coating liquid) for each layer is applied in sequence onto a resin sheet and dried to form a laminate, so there are fewer restrictions on the coating width and length, making it suitable for mass production of the same laminate structure.

The manufacturing method of the present invention may further include a protective film forming step of covering the outermost and innermost circumferential surfaces of the roll body with an insulating protective film.
The production method of the present invention can further include a step of forming a negative electrode current collector exposed portion where the negative electrode current collector layer is exposed, and a positive electrode current collector exposed portion where the positive electrode current collector layer is exposed, on at least a part of the roll body, typically on the outermost peripheral surface and the innermost peripheral surface.
In this case, by connecting a negative electrode lead to the negative electrode current collector exposed portion and a positive electrode lead to the positive electrode current collector exposed portion, electrical connection with other electric components and the like can be achieved.

The present invention makes it possible to efficiently mass-produce rolls of battery elements of any size, each of which is formed by winding a large number of laminated structures in which a negative electrode current collector layer, a negative electrode active material layer, a solid electrolyte layer, a positive electrode active material layer, and a positive electrode current collector layer are sequentially laminated with a resin sheet interposed therebetween.
In addition, by sequentially applying the paste (coating liquid) for each layer onto a resin sheet and drying it to form a laminate, there are fewer restrictions on the coating width and length, making it suitable for mass production of the same laminate structure.

1A and 1B are schematic diagrams of a roll body according to one embodiment of the present invention, in which FIG. 1A is a diagram showing the entire roll body, and FIG. 1B is a diagram showing a cross-sectional layered structure of the roll body. FIG. 1 is a process flow diagram illustrating one embodiment of a manufacturing method of the present invention. 1A and 1B are schematic diagrams for explaining a slitting step in one embodiment of a manufacturing method of the present invention, in which (a) is a perspective view and (b) is a side view. 1A and 1B are schematic diagrams showing cross-sectional stacking configurations of a negative electrode sheet and a positive electrode sheet in one embodiment of the manufacturing method of the present invention, in which (a) is a diagram showing a state in which a negative electrode sheet and a positive electrode sheet are prepared, (b) is a diagram showing a state in which a negative electrode sheet and a positive electrode sheet are stacked, and (c) is a diagram showing a state in which a plurality of negative electrode sheets and positive electrode sheets are stacked. FIG. 2 is a schematic diagram showing a cross-sectional laminate structure when a current collector exposed portion is formed in one embodiment of the manufacturing method of the present invention. FIG. 2 is a schematic diagram showing a cross-sectional laminate structure when a lead is connected to an exposed portion of a current collector in one embodiment of the manufacturing method of the present invention. FIG. 1 is a schematic diagram of an all-solid-state battery according to one embodiment of the present invention.

Fig. 1 is a schematic diagram of a roll body according to one embodiment of the present invention. Fig. 1(a) shows a schematic overall image of a roll body 1 according to one embodiment of the present invention. Fig. 1(b) shows a schematic partial layered structure of the roll body 1.
The roll body 1 of the battery element according to this embodiment is formed by winding a large number of anode sheets 20, each having a cathode current collector layer 22, an anode active material layer 23, and a solid electrolyte layer 24 formed on a long resin sheet 21, and a cathode sheet 30, each having a cathode current collector layer 32, a cathode active material layer 33, and a solid electrolyte layer 34 formed on a long resin sheet 31, with the respective resin sheets facing each other (i.e., facing each other so that the solid electrolyte layers 24, 34 are sandwiched between the anode active material layer 23 and the cathode active material layer 33).
In this embodiment, the solid electrolyte layer 24 is formed on the negative electrode active material layer 23, and the solid electrolyte layer 34 is formed on the positive electrode active material layer 33, but only one of the solid electrolyte layers 24 and 34 may be formed.
The negative electrode sheet 20 and the positive electrode sheet 30 are wound with their resin sheets 21, 31 facing each other, so that the area sandwiched between the resin sheets of the negative electrode sheet and the positive electrode sheet has a layered structure in which the negative electrode collector layer 22, the negative electrode active material layer 23, the solid electrolyte layers 24, 34, the positive electrode active material layer 33, and the positive electrode collector layer 32 are layered in this order, as shown in FIG. 1( b ). This layered structure is electrically insulated by the resin sheets 21, 22 and is wound in large numbers to form a roll body 1 of a battery element.

As the resin sheet, for example, polyimide, polyester, polypropylene, polyethylene, polyvinylidene chloride, polyethylene terephthalate, polyethylene naphthalate, silicone resin, rubber-based resin, etc. can be used. These resin sheets are preferably insulating and stable against heat, and for example, polyimide can be suitably used. It is preferable to set the thickness of the resin sheet to 50 μm or less, preferably 25 μm or less.

The size and structure of the negative electrode current collector are not particularly limited and can be appropriately selected according to the purpose. The material of the negative electrode current collector can be, for example, die steel, gold, platinum, indium, nickel, copper, stainless steel, etc. The shape of the negative electrode current collector can be, for example, foil, plate, mesh, etc.
The method for forming the negative electrode current collector is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include a sputtering method, a vapor deposition method, a CVD method, etc. Alternatively, the negative electrode current collector can be formed by appropriately mixing a metal powder such as copper with a solvent, a resin, etc. to prepare a paste, applying the paste onto a resin sheet, and drying the paste.
The thickness of the negative electrode current collector can be, for example, 5 μm to 500 μm, or preferably 10 μm to 50 μm.

The negative electrode active material layer is not particularly limited as long as it is a layer containing a negative electrode active material, and can be appropriately selected according to the purpose. Examples of the negative electrode active material include lithium, lithium alloys, indium, tin, lead, silicon, silicon oxide, and carbon materials, and lithium-containing phosphates. Specific examples include Li3V2(PO4)3, Li3Fe2(PO4)3, and Li4Ti5O12. Only one type of these negative electrode active material particles may be used, or multiple types may be mixed and used.

The method of forming the negative electrode active material layer is not particularly limited and can be appropriately selected according to the purpose, and examples thereof include sputtering, vapor deposition, and CVD. The negative electrode active material particles can also be mixed with a solvent, a resin, and the like to prepare a paste, and the paste can be applied to a sheet and dried to form the negative electrode active material layer. In addition, when forming the negative electrode active material layer, a known conductive agent or the like may be contained. For example, a negative electrode active material such as carbon powder or graphite powder can be dispersed with a resin such as polyvinylidene fluoride, phenolic resin, furan resin, polyacetylene, or cellulose to prepare a paste, which can be applied and dried on the negative electrode current collector layer to form the negative electrode active material layer. The negative electrode active material layer may be heated or pressed as necessary to obtain a desired density.
The thickness of the negative electrode active material layer is not particularly limited and can be appropriately selected depending on the purpose, but can be 0.05 μm to 100 μm, preferably 0.1 μm to 50 μm, and more preferably 0.5 μm to 25 μm.

The shape and material of the positive electrode current collector layer are not particularly limited and can be appropriately selected according to the purpose. For example, die steel, stainless steel, aluminum, aluminum alloy, titanium alloy, copper, nickel, etc. can be used for the positive electrode current collector layer. For example, the shape of the positive electrode current collector layer can be a foil, a plate, a mesh, etc.
The method for forming the positive electrode current collector layer is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include a sputtering method, a vapor deposition method, a CVD method, etc. Alternatively, the positive electrode current collector layer can be formed by appropriately mixing a solvent, a resin, etc. with a carbon powder, a metal powder, etc. to prepare a paste, and applying the paste onto a resin sheet and drying it.
The thickness of the positive electrode current collector can be, for example, 5 μm to 500 μm, or preferably 10 μm to 50 μm.

The positive electrode active material layer is not particularly limited as long as it contains a positive electrode active material, and can be appropriately selected according to the purpose. Examples of the positive electrode active material include lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, composite oxides in which a part of these oxides is replaced with other transition metals, transition metal compounds such as manganese dioxide and vanadium pentoxide, and transition metal chalcogen compounds such as iron sulfide. Specific examples include Li3V2(PO4)3, Li3Fe2(PO4)3, LiMnPO4, LiCoO2, LiNiO2, LiFePO4, LiCoPO4, LiNiPO4, LiCo1/3Ni1/3Mn1/3O2, LiMn2O4, LiNi0.5Mn1.5O4, and Li4Ti5O12. Only one of these positive electrode active materials may be used, or multiple types may be mixed and used.

The method for forming the positive electrode active material layer is not particularly limited and can be appropriately selected according to the purpose, and examples thereof include sputtering, vapor deposition, pulse laser deposition, CVD, aerosol deposition, spray, flux, and sol-gel methods. The positive electrode active material layer can also be formed by appropriately mixing a solvent, a resin, etc. with the positive electrode active material particles to prepare a paste, applying the paste onto a sheet, and drying it. When forming the positive electrode active material layer, a known conductive agent or the like may be contained. For example, a positive electrode active material and a conductive agent such as acetylene black are dispersed together with a resin such as polyvinylidene fluoride to prepare a paste, which can be applied and dried on a positive electrode current collector layer to form a positive electrode active material layer. The positive electrode active material layer may be heated or pressed as necessary to obtain a desired density.
The thickness of the positive electrode active material layer is not particularly limited and can be appropriately selected depending on the purpose, but can be 0.05 μm to 100 μm, preferably 0.1 μm to 50 μm, and more preferably 0.5 μm to 25 μm.

The solid electrolyte layer is not particularly limited as long as it is a layer composed of lithium oxynitride phosphate, a sulfide-based lithium ion conductive solid electrolyte, or an oxide-based lithium ion conductive solid electrolyte, and can be appropriately selected according to the purpose. Examples include LiPON, Li3Zr2Si2PO12, Li7La3Zr2O12, Li5La3Ta2O12, Li1+xAlxTi2-x(PO4)3, Li1.5Ti1.7Al0.8P2.8Si0.2O12, and La2/3-xLi3xTiO3.
The method for forming the solid electrolyte layer is not particularly limited and can be appropriately selected depending on the purpose. Examples include sputtering, vapor deposition, pulsed laser deposition, CVD, aerosol deposition, spraying, flux, and sol-gel methods. The solid electrolyte layer can also be formed by mixing a solvent, resin, etc. with solid electrolyte particles appropriately to prepare a paste, applying the paste onto a sheet, and drying it.

Examples of the resin include polyacrylonitrile, polyvinylidene fluoride, polytetrafluoroethylene, polyhexafluoropropylene, polyethylene oxide, polypropylene oxide, polyphosphazene, polysiloxane, polyvinyl acetate, polyvinyl alcohol, polymethyl methacrylate, polyacrylic acid, polymethacrylic acid, styrene-butadiene rubber, nitrile-butadiene rubber, polystyrene, and polycarbonate.
As the solvent, ethylene carbonate, propylene carbonate, butylene carbonate, γ-butyrolactone, γ-valerolactone, diethoxyethane, tetrahydrofuran, 2-methyltetrahydrofuran, 1,3-dioxane, methyl acetate, methyl propionate, dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, and the like can be used.
The thickness of the solid electrolyte layer is not particularly limited and can be appropriately selected depending on the purpose, but can be 0.05 μm to 100 μm, preferably 0.1 μm to 50 μm, and more preferably 0.5 μm to 25 μm.

Next, an example of the method for producing the all-solid-state battery of the present invention will be described.
2 is a process flow diagram for explaining one embodiment of the manufacturing method of the present invention. The manufacturing method of the all-solid-state battery of this embodiment includes the steps of preparing a wide and long resin sheet 21, preparing a negative electrode roll-shaped raw material in which a large number of negative electrode sheets 20 each having a negative electrode current collector layer 22, a negative electrode active material layer 23, and a solid electrolyte layer 24 laminated thereon are wound, preparing a positive electrode roll-shaped raw material in which a large number of positive electrode sheets 30 each having a positive electrode current collector layer 32, a positive electrode active material layer 33, and a solid electrolyte layer 34 laminated thereon are wound, and winding the negative electrode roll-shaped raw material from the negative electrode roll. The method includes a slitting process in which the negative electrode sheet 20 being fed and the positive electrode sheet 30 being unwound from a positive electrode roll are overlapped such that the solid electrolyte layers 24, 34 are sandwiched between the negative electrode active material layer 23 and the positive electrode active material layer 33, and the overlapped negative electrode sheet 20 and the positive electrode sheet 30 are slit into a plurality of narrow-width sheets, and further includes a winding process in which the plurality of narrow-width sheets are each wound into a roll to form a roll of battery element.
In this embodiment, the solid electrolyte layer 24 is formed on the negative electrode active material layer 23, and the solid electrolyte layer 34 is formed on the positive electrode active material layer 33. However, it is also possible to form only one of the solid electrolyte layers 24, 34.

3A and 3B are schematic diagrams for explaining a slitting step in one embodiment of the manufacturing method of the present invention, in which (a) is a perspective view and (b) is a side view.
In the slitting process, the negative electrode sheet 20 unwound from the negative electrode roll and the positive electrode sheet 30 unwound from the positive electrode roll are stacked, for example, by nip rolls 4, and cut into a plurality of narrow-width sheets by a slitter head 5. Each narrow-width sheet is then wound into a roll to form a plurality of roll bodies 1.
The slitting process is performed by a slitter. The slitter cuts a wide sheet unwound from a roll of raw material into a plurality of narrow-width sheets using a slitter head, and winds each narrow-width sheet into a roll on a core. For example, as shown in FIG. 3B, when the narrow-width sheet is wound up a predetermined number of times or to a predetermined diameter, the end of the roll is cut by cutter mechanisms 61, 62, and the roll body 1 wound into a narrow roll is taken out, and the core is rotated by mechanisms 71, 72 to return the core into the slitter.

FIG. 4 is a schematic diagram showing a stacked structure of a negative electrode sheet and a positive electrode sheet in one embodiment of the manufacturing method of the present invention.
An example of the manufacturing method of the present invention will be described with reference to FIG. 4. A wide and long resin sheet 21 is prepared, and a negative electrode current collector layer 22, a negative electrode active material layer 23, and a solid electrolyte layer 24 are laminated in this order.
The method of forming the laminated layers is, for example, to prepare a paste by appropriately mixing the base material of each layer with a solvent, resin, etc., and then to apply the paste of each layer on a resin sheet in sequence by other application methods such as gravure method, screen method, etc., and dry it to form the negative electrode sheet 20. After application, it may be heated and pressed by a roll press or the like as necessary. Similarly, a positive electrode sheet 30 for forming a positive electrode is formed. In this way, a negative electrode roll-shaped raw material having a multiplicity of negative electrode sheets 20 wound around it and a positive electrode roll-shaped raw material having a multiplicity of positive electrode sheets 30 wound around it, each having a laminated structure as shown in FIG. 4(a), are prepared.

Next, the negative electrode roll and the positive electrode roll are set in the unwinding mechanism of the slitting device, and the negative electrode sheet 20 is unwound from the negative electrode roll, and the positive electrode sheet 30 is unwound from the positive electrode roll. The negative electrode sheet 20 unwound from the negative electrode roll and the positive electrode sheet 30 unwound from the positive electrode roll are stacked by nip rolls 4 with their solid electrolytes facing each other, resulting in a laminated configuration as shown in FIG.
The negative electrode sheet 20 and the positive electrode sheet 30 in this state are cut into multiple narrow sheets by a slitter head 5 and wound into a roll, resulting in a state in which multiple negative electrode sheets 20 and positive electrode sheets 30 are stacked as shown in Fig. 4(c) . In this stacked state, the solid electrolyte layers 24, 34 face each other, and the negative electrode collector layer 22 and the positive electrode collector layer 32 are insulated by the resin sheets 21, 31 to form a roll body 1.

In FIG. 4, the negative electrode sheet 20 and the positive electrode sheet 30 are stacked with the solid electrolytes facing each other using the nip rolls 4, but they may also be stacked with the resin sheets facing each other. Regardless of which way they are stacked, the resin sheets of the negative electrode sheet 20 and the positive electrode sheet 30 are stacked together when rolled up, and the area sandwiched between the resin sheets has a stacked structure in which the negative electrode collector layer, the negative electrode active material layer, the solid electrolyte layer, the positive electrode active material layer, and the positive electrode collector layer are stacked in that order.

The manufacturing method of the present invention has been described above, but the present invention can add necessary processes depending on the battery shape and application. For example, annealing treatment may be performed in the rolled state to fully bring out the characteristics of the roll body 1.

Alternatively, a current collector exposed portion where the negative electrode current collector layer and the positive electrode current collector layer are exposed may be formed on at least a part of the rolled body 1, typically on the outermost and innermost surfaces (FIG. 5), and an anode lead may be connected to the current collector exposed portion of the negative electrode current collector layer, and a cathode lead may be connected to the current collector exposed portion of the positive electrode current collector layer, thereby enabling electrical connection with other electric components, etc. (FIG. 6). Methods that can be used to form the exposed portions include, for example, shot blasting, sand blasting, polishing, elution, and cutting.
The method may also include a protective film forming step of covering the outermost and innermost circumferential surfaces of the roll body with an insulating protective film, except for exposed portions of the current collector.

The roll body 1 produced as described above is housed in a battery case, for example as shown in FIG. 7. There are no particular limitations on the battery case and it can be appropriately selected depending on the purpose, and examples of the battery case include known laminate films and housings that can be used in conventional all-solid-state batteries. There are no particular limitations on the shape of the all-solid-state battery and it can be appropriately selected depending on the purpose, and examples of the shape include cylindrical, square, button, coin, and flat types.

REFERENCE SIGNS LIST 1 Roll body 20 Negative electrode sheet 21, 31 Resin sheet 22 Negative electrode current collector layer 23 Negative electrode active material layer 24, 34 Solid electrolyte layer 32 Positive electrode current collector layer 33 Positive electrode active material layer 4 Nip roll 5 Slitter head 61, 62 Cutter mechanism 71, 72 Roll core rotation mechanism

Claims (5)

preparing a negative electrode roll-shaped raw material by winding a negative electrode sheet having a negative electrode current collector layer and a negative electrode active material layer provided in this order on a first surface of a wide and long first resin sheet;
a step of preparing a rolled positive electrode raw material by winding a positive electrode sheet having a positive electrode current collector layer and a positive electrode active material layer provided in this order on a first surface of a wide and long second resin sheet, and a solid electrolyte layer is further provided on at least one of the negative electrode active material layer and the positive electrode active material layer;
a slitting process of overlapping the negative electrode sheet unwound from the negative electrode roll and the positive electrode sheet unwound from the positive electrode roll such that the first surface of the first resin sheet faces the first surface of the second resin sheet, or such that the surface of the first resin sheet opposite the first surface faces the surface of the second resin sheet opposite the first surface, and slitting the negative electrode sheet and the positive electrode sheet in a state where they are overlapped into a plurality of narrow-width sheets;
and a winding step of winding each of the narrow sheets into a roll to form a roll of battery elements ,
the step of preparing a negative electrode roll-shaped raw material includes a step of coating the negative electrode current collector layer and the negative electrode active material layer in this order on the wide and long first resin sheet,
the step of preparing a positive electrode roll includes a step of coating the positive electrode current collector layer and the positive electrode active material layer in this order on the wide and long second resin sheet,
the solid electrolyte layer is further formed by coating on at least one of the negative electrode active material layer and the positive electrode active material layer . the slitting step includes a step of cutting the negative electrode sheet unwound from the negative electrode roll and the positive electrode sheet unwound from the positive electrode roll into the plurality of narrow-width sheets by a slitter head in a state where the negative electrode sheet and the positive electrode sheet are overlapped with each other,
The manufacturing method according to claim 1 , wherein the winding step includes a step of cutting off an end of the narrow-width sheet when the narrow-width sheet has been wound up a predetermined number of times or to a predetermined diameter. The method according to claim 1 or 2 , further comprising a protective film forming step of covering at least an outermost surface and an innermost surface of the roll body with an insulating protective film. The manufacturing method according to claim 1 , further comprising a step of forming, on the roll body, a negative electrode current collector exposed portion where the negative electrode current collector layer is exposed, and a positive electrode current collector exposed portion where the positive electrode current collector layer is exposed. The method according to claim 4 , further comprising the step of connecting a negative electrode lead to the negative electrode current collector exposed portion and connecting a positive electrode lead to the positive electrode current collector exposed portion.

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