JPWO2019031438A1 - Electrode sheet manufacturing method, all-solid-state battery and all-solid-state battery manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing an electrode sheet for use in a thin all-solid-state battery having a small internal resistance and less likely to cause an internal short circuit by using a polymer solid electrolyte. [Solution] A step of preparing a metal foil (12) having a heat-fusible resin frame (13) formed on one surface, and an active material on the metal foil and inside the heat-fusible resin frame. A step of applying an electrode mixture containing particles (17) to form an active material layer, a step of forming an inorganic solid electrolyte layer containing inorganic solid electrolyte particles (20) on the active material layer, and a polymer A solution supplying step of supplying a polymer solid electrolyte solution containing a compound and an alkali metal salt to permeate the active material layer and the inorganic solid electrolyte layer, and polymerizing the polymer compound after the solution supplying step. Thus, a method of manufacturing an electrode sheet, comprising a curing step of integrally forming a polymer solid electrolyte (18, 21) between the active material particles and between the inorganic solid electrolyte particles. [Selection diagram] Figure 1

Description

The present invention relates to an all-solid electrode sheet using an inorganic solid electrolyte and a polymer solid electrolyte. The present invention also relates to an all solid film type battery using an inorganic solid electrolyte and a polymer solid electrolyte.

Development of a solid-state lithium-ion secondary battery using a solid electrolyte instead of a liquid electrolytic solution has been actively conducted. By using the solid electrolyte, the battery can be made thinner, and excellent characteristics such as no leakage of the electrolytic solution can be obtained. Inorganic solid electrolytes, polymer solid electrolytes, and polymer gel electrolytes are known as such solid electrolytes.

Inorganic solid electrolytes having excellent ionic conductivity have been developed in recent years. However, since the form is particulate, there is a problem that the internal resistance of the battery increases and the battery capacity decreases due to poor contact with the active material particles.

The polymer gel electrolyte is a gel solid electrolyte in which an organic solvent containing an electrolyte salt is retained in a polymer network. It has been proposed to improve the contact state between the active material particles and the solid electrolyte by impregnating the polymer gel electrolyte between the active material particles forming the electrodes. Patent Document 1 describes a polymer (gel-like) solid electrolyte battery in which a monomer composition is applied to the surface of a positive electrode active material layer, a part of the composition is impregnated in the positive electrode active material layer, and then thermally polymerized. ing. Further, in Patent Document 2, by adhering a solid electrolyte solution in which a gel-like solid electrolyte is dissolved in a solvent onto an active material layer, good adhesion is formed at a bonding interface between the solid electrolyte and the active material. A solid electrolyte battery is described.

On the other hand, regarding the thinning of batteries, lithium-ion secondary batteries using a laminated exterior material in which a resin film is bonded to both sides of a metal foil are used for smartphones, tablet terminals and the like.

Further, in Patent Document 3, in a power storage device in which a first metal foil layer, a positive electrode active material, a separator of a porous film, a negative electrode active material layer, and a second metal foil layer are laminated, the outer periphery of the positive and negative electrode active material layers is A first metal foil layer, a separator end, and a second metal foil layer are bonded together via a peripheral sealing layer containing a heat-fusible resin that surrounds the first metal foil layer and the second metal foil layer separator. There is described a thin electricity storage device in which an insulating resin film is laminated on the surface opposite to the surface on the side with the exposed metal portion left (FIG. 4). By exchanging electricity through the exposed metal part, the tab lead wire led out from the electrode is not necessary, and the first and second metal foil layers serve both as a current collector and an outer covering material, so that the outer covering material is further improved. It is said that the power storage device can be made thinner without requiring

JP, 7-326383, A JP-A-11-195433 JP, 2016-042459, A

However, the solid electrolyte layer made of the polymer gel electrolyte has a problem of low strength. Therefore, when it is used for a film-shaped battery having flexibility, the separator layer separating the two electrodes of the battery may be damaged due to the deformation of the battery, causing an internal short circuit. Further, if the content of the organic solvent is excessively increased in order to increase the mobility of the electrolyte salt in the polymer gel electrolyte, the problem of liquid leakage remains. In addition, the method of impregnating the active material layer with the solution of the polymer gel electrolyte has problems that it takes time to impregnate the solution and it is difficult to permeate the solution into the entire active material layer.

On the other hand, it is possible to use a polymer solid electrolyte to improve the strength and durability of the separator layer. The polymer solid electrolyte is a solid electrolyte containing an electrolyte salt in a polymer. However, in the solid polymer electrolyte, the mobility of the electrolyte salt in the solid polymer is low. Therefore, if the separator layer is too thick, there is a problem that the internal resistance of the battery increases and practical charge/discharge characteristics cannot be obtained. On the other hand, if the separator layer is too thin, there is still a concern that the polymer solid electrolyte may damage the separator layer due to repeated bending deformation of the battery and may cause an internal short circuit.

Further, although Patent Document 3 discloses a method for manufacturing a lithium-ion battery using a non-aqueous electrolyte solution, there is no description of a specific manufacturing method for an all-solid-state battery that does not require a tab lead wire.

The present invention has been made in consideration of the above, and can be used for a thin all-solid-state battery having a small internal resistance and less likely to cause an internal short-circuit, a method for manufacturing the same, and such an all-solid-state battery using a polymer solid electrolyte. An object of the present invention is to provide a method for manufacturing a simple electrode sheet.

The electrode sheet manufacturing method of the present invention comprises a step of preparing a metal foil having a heat-fusible resin frame formed on one surface, and the active material particles on the metal foil and inside the heat-fusible resin frame. A step of forming an active material layer by applying an electrode mixture containing, a step of forming an inorganic solid electrolyte layer containing inorganic solid electrolyte particles on the active material layer, a polymer from the inorganic solid electrolyte layer A polymer solid electrolyte solution containing a compound and an alkali metal salt is supplied, and a solution supplying step of permeating the active material layer and the inorganic solid electrolyte layer, and the polymer compound is polymerized after the solution supplying step. Accordingly, a curing step of integrally forming a polymer solid electrolyte between the active material particles and between the inorganic solid electrolyte particles is included.

Here, the polymer solid electrolyte solution refers to a raw material solution for forming the polymer solid electrolyte, and the polymer compound in the polymer solid electrolyte solution is polymerized to form the polymer solid electrolyte. Further, polymerizing the polymer compound includes crosslinking the polymer compound with a crosslinking agent. By this method, the electrode has a structure in which the gaps between the active material particles are filled with the solid polymer electrolyte, so that the contact state between the active material particles and the solid polymer electrolyte becomes good. Further, since the inorganic solid electrolyte particles and the polymer solid electrolyte filling the gaps between them constitute a separator layer located between the inorganic solid electrolyte particles and the counter electrode during battery production, the ionic conductivity and strength of the separator layer can be compatible at a high level. Moreover, since the solid polymer electrolyte in the electrode and the solid polymer electrolyte in the separator layer are integrally formed, the interface resistance between the electrode and the separator layer can be further reduced.

In another electrode sheet manufacturing method of the present invention, the heat-fusible resin is formed later. Specifically, another electrode sheet manufacturing method of the present invention comprises a step of preparing a metal foil, and a step of applying an electrode mixture containing active material particles onto the metal foil to form an active material layer. A step of forming an inorganic solid electrolyte layer containing inorganic solid electrolyte particles on the active material layer, and supplying a polymer solid electrolyte solution containing a polymer compound and an alkali metal salt, the active material layer and the inorganic solid A solution supplying step of permeating the electrolyte layer, and after the solution supplying step, by polymerizing the polymer compound, a solid polymer electrolyte is integrally formed between the active material particles and between the inorganic solid electrolyte particles. Curing step and at any stage from after the active material layer forming step to after the curing step, forming a heat-fusible resin frame on the metal foil and around the active material layer. And a process.

Preferably, the metal foil has a heat resistant resin layer on the surface opposite to the surface on which the active material layer is formed. As a result, the metal foil is protected by the heat-resistant resin layer, so that the current collector sheet can be used as it is as a battery exterior material.

Preferably, in the step of forming the active material layer, the electrode mixture further contains the inorganic solid electrolyte particles. As a result, the mobility of electric charges moving through the gaps of the active material particles is improved, and the internal resistance of the electrode is further reduced.

Preferably, in the step of forming the active material layer, the electrode mixture is applied by screen printing. Thereby, the active material layer can be applied only in a predetermined range such as inside the heat-fusible resin frame at low cost.

Preferably, the solution supplying step is a step of supplying the polymer solid electrolyte solution from above the inorganic solid electrolyte layer by a non-contact coating method. Here, the non-contact coating method refers to a method of supplying a solution without bringing a member such as a roll or a nozzle into contact with the surface of the inorganic solid electrolyte layer. Thereby, the polymer solid electrolyte solution can be supplied without damaging the inorganic solid electrolyte layer and the active material layer.

An all-solid-state battery of the present invention includes a first metal foil, a first electrode including first active material particles and a first solid polymer electrolyte in an electrode that fills a gap between the first active material particles, and inorganic solid electrolyte particles. And a separator layer containing a polymer solid electrolyte in a separator layer filling the gap between the inorganic solid electrolyte particles, and having a polarity opposite to that of the first electrode, and a gap between the second active material particles and the second active material particles. The second electrode including the second solid polymer electrolyte in the electrode and the second metal foil are laminated in this order. Then, at least one of the first solid polymer electrolyte in the electrode and the second solid polymer electrolyte in the electrode is formed integrally with the solid polymer electrolyte in the separator layer in a portion in contact with the first or second electrode. ing. And, it has a heat-fusible resin wall that surrounds the outer periphery of the first electrode, the separator layer, and the second electrode, and that joins the first metal foil and the second metal foil.

With this configuration, the contact state between the active material particles and the solid polymer electrolyte is improved, the ionic conductivity and strength of the separator layer can be compatible at a high level, and the interface resistance between the electrode and the separator layer can be further reduced. Further, by exchanging electricity through the metal foil, the tab lead wire led out from the electrode becomes unnecessary.

Preferably, the first metal foil has a first heat resistant resin layer on a surface opposite to the first electrode, and/or the second metal foil has a second heat resistant resin layer on a surface opposite to the second electrode. It has a heat resistant resin layer.

Preferably, the solid polymer electrolyte in the first electrode, the solid polymer electrolyte in the separator layer, and the solid polymer electrolyte in the second electrode are integrally formed. This can further reduce the internal resistance of the battery.

One all-solid-state battery manufacturing method for manufacturing the all-solid-state battery includes a step of manufacturing a first electrode sheet by any of the above methods, and a polarity opposite to that of the first electrode sheet by any of the above-mentioned methods. A step of manufacturing a second electrode sheet having: a step of superimposing the first electrode sheet and the second electrode sheet so that the respective heat-fusible resin frames are bonded to each other; And a sealing step of forming a heat-fusible resin wall by heat-fusing the heat-fusible resin frames of the second electrode sheet.

Another all-solid-state battery manufacturing method for manufacturing the above all-solid-state battery will be described later as an embodiment.

According to the electrode sheet manufacturing method, the all-solid-state battery, or the all-solid-state battery manufacturing method of the present invention, since the electrolyte of the all-solid battery is composed of the inorganic solid electrolyte and the polymer solid electrolyte, there is no risk of liquid leakage.

Further, since a low-viscosity solid polymer electrolyte solution is permeated into the gaps of the active material particles and the gaps of the inorganic solid electrolyte particles and polymerized to form a solid polymer electrolyte, the solid polymer electrolyte solution is used as the active material layer. And it is easy to penetrate a wide range of the inorganic solid electrolyte layer. Since the solid polymer electrolyte fills the gaps between the active material particles after the polymerization, a contact state between the solid polymer electrolyte and the active material particles is good, and a battery having low internal resistance can be obtained. Furthermore, since the solid polymer electrolyte in at least one of the electrodes is integrally formed with the solid polymer electrolyte in the separator layer, the interface resistance between the electrode and the separator layer is suppressed, and a battery having low internal resistance can be obtained.

In addition, since the separator layer can include an inorganic solid electrolyte having a higher electrolyte salt mobility and a higher lithium ion transport number than the polymer solid electrolyte, the internal resistance of the battery can be reduced and the charge/discharge characteristics can be improved. Further, since the separator layer contains the inorganic solid electrolyte particles having a hardness higher than that of the polymer solid electrolyte, the separator layer is less likely to be damaged even by repeated bending deformation of the battery, and an internal short circuit is less likely to occur. Since the separator layer can be formed thin, the internal resistance of the battery can be reduced and the charge/discharge characteristics can be improved. Thereby, the ionic conductivity and the strength of the separator layer can be compatible at a high level.

Further, since electricity can be transferred to and from the outside through the metal foil of the current collector sheet, the tab lead is unnecessary. Furthermore, since the current collector sheet can also serve as the exterior material, a thinner battery can be obtained.

It is a schematic diagram which shows the cross-section of the electrode sheet by the manufacturing method of the electrode sheet of 1st Embodiment of this invention. It is a process flow figure of the manufacturing method of the electrode sheet of a 1st embodiment of the present invention. It is a schematic diagram which shows the cross-section of the modification of the electrode sheet by the electrode sheet manufacturing method of 1st Embodiment of this invention. It is a process flow figure of the modification of the electrode sheet manufacturing method of a 1st embodiment of the present invention. It is a schematic diagram which shows the cross-section of the all-solid-state battery of 2nd Embodiment of this invention. It is a process flow figure of the all-solid-state battery manufacturing method of a 2nd embodiment of the present invention. It is a schematic diagram which shows the cross-section of the all-solid-state battery of 3rd Embodiment of this invention. It is a schematic diagram which shows the cross-section of the negative electrode sheet (2nd electrode sheet) used with the all-solid-state battery manufacturing method of 3rd Embodiment of this invention. It is a process flow figure of the all-solid-state battery manufacturing method of a 3rd embodiment of the present invention. It is a process flow figure of the modification of the negative electrode sheet (2nd electrode sheet) manufacturing process in the manufacturing method of the electrode sheet of a 3rd embodiment of the present invention. It is a schematic diagram which shows the cross-section of the all-solid-state battery of 4th Embodiment of this invention. It is a process flow figure of the all-solid-state battery manufacturing method of a 4th embodiment of the present invention. It is a schematic diagram which shows the cross-section of the all-solid-state battery of 5th Embodiment of this invention. It is a process flow figure of the all-solid-state battery manufacturing method of a 5th embodiment of the present invention. It is a process flow figure of the modification of the all-solid-state battery manufacturing method of a 5th embodiment of the present invention. It is a charge/discharge test result of the all-solid-state battery of an experimental example. It is a process flow figure of the modification of the manufacturing method of the electrode sheet of a 1st embodiment of the present invention.

As a first embodiment of the present invention, a method for manufacturing an electrode sheet for an all-solid-state lithium-ion battery will be described with reference to FIGS.

First, referring to FIG. 1, an electrode sheet 10 manufactured in the present embodiment is configured by laminating a metal foil 12, an electrode 16, and a separator layer 19 in this order. The electrode is a positive electrode or a negative electrode. When the electrode 16 is a positive electrode, the electrode sheet 10 is a positive electrode sheet, and when the electrode 16 is a negative electrode, the electrode sheet 10 is a negative electrode sheet.

The metal foil 12 has a heat-fusible resin frame 13 formed on the peripheral portion of one surface thereof, and has a heat resistant resin layer 14 on the opposite surface thereof, and the metal foil is exposed at a part of the heat resistant resin layer. The exposed portion 15 is formed. The electrode 16 and the separator layer 19 are formed inside the heat-fusible resin frame. The electrode 16 is composed of the active material particles 17 and the in-electrode polymer solid electrolyte 18 filling the gaps between the active material particles 17. The separator layer 19 is composed of the inorganic solid electrolyte particles 20 and the polymer solid electrolyte 21 in the separator layer filling the gaps. Details of each component will be described in the description of the manufacturing method.

The electrode sheet manufacturing method S10 of the present embodiment will be described with reference to FIG.
(S11) a step of preparing a metal foil 12 having a heat-fusible resin frame 13 formed on one surface,
(S12) a step of forming an active material layer on the metal foil,
(S13) a step of forming an inorganic solid electrolyte layer on the active material layer,
(S14) a solution supplying step of supplying a polymer solid electrolyte solution from above the inorganic solid electrolyte layer to permeate the active material layer and the inorganic solid electrolyte layer;
(S15) a curing step of polymerizing the polymer compound.

In step S11 of preparing the metal foil 12, the heat-fusible resin frame 13 is formed on the peripheral edge of one surface of the metal foil 12. Further, a heat resistant resin layer 14 is laminated on the surface of the metal foil opposite to the heat fusible resin frame, and an exposed portion 15 where the metal foil is exposed is formed in a part of the heat resistant resin layer. ..

Various metal materials having electronic conductivity can be used for the metal foil 12. As the metal foil for the positive electrode, for example, aluminum, titanium, or stainless steel foil can be used, and preferably aluminum foil having excellent oxidation resistance is used. The thickness of the aluminum foil is preferably 5 to 25 μm. As the metal foil for the negative electrode, for example, a foil of copper, nickel, aluminum, or iron can be used, and a copper foil that is stable in a reducing field and has excellent electrical conductivity is preferably used. The thickness of the copper foil is preferably 5 to 15 μm.

As the heat-fusible resin frame 13, various heat-fusible resins such as polyethylene and polypropylene can be used. The heat-fusible resin frame preferably comprises an unstretched film. This is because it has excellent heat sealability, moisture resistance, and flexibility. The thickness of the heat-fusible resin frame (dimension in the vertical direction in FIG. 1) is 100 to 120 when the total thickness of the electrode 16 and the separator layer 19 formed in a later step is 100. preferable. This is because when the battery is manufactured, it can be reliably fused with the heat-fusible resin frame of the opposing metal foil. For example, when the thickness of the electrode is 15 μm and the thickness of the separator layer is 5 μm, the thickness of the heat-fusible resin frame is preferably 20 to 24 μm. The width of the frame portion of the heat-fusible resin frame (width of 13A surface in FIG. 1) is preferably 5 mm or more. This is because if the width of the frame is too narrow, the sealing property of the battery will be insufficient. On the other hand, the width of the frame portion of the heat-fusible resin frame is preferably 20 mm or less. This is because the width required for ensuring the sealing property is sufficient, and the battery becomes uselessly large even if the width of the frame is too wide.

The heat-fusible resin frame 13 can be formed into a frame shape by adhering the film to the metal foil 12 with an adhesive layer (not shown) and removing the central portion. For example, a masking tape is attached to the center of the metal foil in advance, and the heat-fusible resin film is adhered to the entire surface of the metal foil from the top of the masking tape. And the heat-fusible resin film can be removed. Alternatively, the heat-fusible resin frame can be formed by inkjet printing, screen printing, or the like.

Although the heat resistant resin layer 14 is not an essential component of the present invention, the metal foil 12 preferably includes the heat resistant resin layer. This is because the metal foil 12 can be protected after the battery is manufactured. The heat-resistant resin layer 14 is made of a material that can withstand heating when the heat-fusible resin frame 13 is heat-sealed, and for example, a polyamide film, a polyester film or the like can be used. Above all, it is preferable to use a biaxially stretched polyethylene terephthalate (PET) film. Further, the heat resistant resin layer may be a single layer film or may be a laminate of a plurality of films. The thickness of the heat resistant resin layer is preferably 10 μm to 100 μm.

The heat resistant resin layer 14 can be laminated by adhering the above film to the metal foil 12 with an adhesive layer (not shown). To form the exposed portion 15, for example, a masking tape is previously attached to the portion of the metal foil, a film of heat resistant resin is adhered to the entire surface of the metal foil from above the masking tape, and a cut is made with a cutter or a laser. Then, the masking tape, the adhesive layer and the heat resistant resin film can be removed.

The step S12 of forming the active material layer is performed by applying the electrode mixture containing the active material particles 17 on the metal foil 12 and inside the heat-fusible resin frame 13.

The electrode mixture is made into a paste by adding a conductive auxiliary agent, a binder, a filler and the like to the active material particles 17 as necessary and adding an appropriate amount of a solvent.

Regarding the electrode mixture, as the positive electrode active material 17, a known material such as LiCoO ₂ or LiNiO ₂ that absorbs and releases Li ions can be used. As the conduction aid, known electron conductive materials such as acetylene black, Ketjen black, other carbon black, metal powder, and conductive ceramics material can be used. The amount of the conductive additive added is typically several% by weight based on the positive electrode active material. As the binder, known materials such as polytetrafluoroethylene (PTFE) and polyvinylidene fluoride (PVdF) can be used. A material having ionic conductivity can also be used as the binder. As the ionic conductive binder, for example, an ionic conductive binder containing a polymer electrolyte composition obtained by graft-polymerizing a skeleton of an ionic liquid onto a fluorine-based polymer such as PVdF is disclosed in JP-A-2005-038870. It is disclosed in the official gazette. Further, it is also possible to use other well-known lithium ion conductive polymer matrix in which a Li metal salt is held in an ether polymer such as polyethylene oxide or polyethylene oxide as a binder. The addition amount of the binder is typically several% by weight based on the positive electrode active material. As the filler, known materials such as olefin polymers such as polypropylene and zeolite can be used. The amount of the filler added is typically 0 to several% by weight based on the positive electrode active material. As the solvent, a well-known organic solvent such as N-methyl-2-pyrrolidone (NMP) can be used.

Regarding the electrode mixture, as the negative electrode active material 17, a well-known material such as graphite or coke that absorbs and releases Li ions can be used. As the conductive additive, binder, and filler added to the negative electrode active material, the same ones added to the positive electrode active material can be used. As the solvent, a known organic solvent such as NMP can be used.

Since the electrode mixture is applied only to the inside of the heat-fusible resin frame 13, it is not possible to adopt the die coating method or the comma coating method which is generally used in the production of conventional lithium ion batteries. The method for applying the electrode mixture is preferably screen printing. This is because the area to be coated can be determined according to the shape of the battery. Moreover, even if the area is large, the electrode mixture paste can be applied to a uniform thickness while suppressing the cost increase. When applying the electrode mixture onto the metal foil 12, a primer coating (undercoating) may be previously performed on the surface of the metal foil in order to improve the adhesion between the active material particles 17 and the metal foil 12. After the electrode mixture is applied on the metal foil, the active material layer is formed by drying and removing the solvent. Note that the active material layer may be compressed by pressing after drying.

The thickness of the active material layer, that is, the thickness of the electrode 16 is preferably 5 to 30 μm, more preferably 10 to 20 μm. This is because if the electrodes are too thin, sufficient battery capacity cannot be obtained. On the other hand, if the electrode is too thick, it becomes difficult to uniformly permeate the solid polymer electrolyte solution into the electrode, and voids are likely to occur inside the electrode. Further, if the electrode is too thick, the migration distance of Li ions in the polymer solid electrolyte in the electrode becomes long and the charge/discharge rate of the battery is lowered.

When the electrode mixture is applied by the screen printing method, the screen is applied from above the heat-fusible resin frame 13, and the inner wall surface of the heat-fusible resin frame is filled in the frame of the heat-fusible resin frame. It is not possible to apply the electrode mixture until just before. However, this is not a problem in this embodiment. The reason will be described later.

The step S13 of forming the inorganic solid electrolyte layer is performed by applying an electrolyte mixture containing the inorganic solid electrolyte particles 20 onto the active material layer.

The electrolyte mixture is made into a paste by adding a binder, a filler and the like to the inorganic solid electrolyte particles 20 as needed and adding an appropriate amount of a solvent. A well-known material such as PVdF can be used as the binder. As the solvent, a known organic solvent such as NMP can be used.

The inorganic solid electrolyte _{20, La 2 / 3x Li 3x} TiO 3 with high lithium ion conductivity _{(LLT), Li 1 + x} Al y Ti 2-y (PO 4) 3 (LATP), Li 1 + x Al y Ge Particles such as _2-y (PO ₄ ) ₃ (LAGP) can be used. LAGP is preferably used. This is because the structure is stable, and the reaction does not easily occur even if it comes into contact with other materials when forming a paste during the production of the electrode sheet. Preferably, LAGP is used as the inorganic solid electrolyte and PVdF is used as the binder. Not only are the respective performances good, but according to this combination, PVdF does not react with the alkali salt to cause gelation. Alternatively, preferably, an ionic conductive binder is used as the binder. This is because the mobility of lithium ions in the electrode is improved.

The particle size of the inorganic solid electrolyte particles 20 is preferably 0.1 μm to 1 μm. This is because if the particle size is too small, the dispersibility in forming a paste becomes poor and the particles easily aggregate to form large particles. On the other hand, if the particle size is too large, the flatness of the surface of the separator layer 19 deteriorates, and the polymer solid electrolyte 21 having a low lithium ion mobility occupies a large proportion in the separator layer, and the lithium ions passing through the separator layer are increased. This is because the mobility of is easily damaged.

The electrolyte mixture is preferably applied by screen printing. This is because the area to be coated can be determined according to the shape of the battery. Further, even if the area is large, the electrolyte mixture paste can be applied to a uniform thickness while suppressing the cost increase. After coating the active material layer with the electrolyte mixture, it is dried to remove the solvent, whereby the inorganic solid electrolyte layer is formed. Preferably, the inorganic solid electrolyte layer is formed so as to cover the entire active material layer.

The preferable range of the thickness of the separator layer 19 varies depending on the all-solid-state battery manufacturing method described later. The thickness of the separator layer of the battery produced is preferably 20 μm or less, more preferably 10 μm or less, and particularly preferably 6 μm or less. This is because if the separator layer is too thick, the internal resistance of the battery will increase. Even if the separator layer is thin, a short circuit is unlikely to occur due to the inclusion of the inorganic solid electrolyte particles 20 having high strength and hardness. On the other hand, regarding the thickness of the separator layer of the battery, the thickness of the thinnest portion is preferably 1 μm or more, more preferably 2 μm or more. This is because if the separator layer is too thin, it will be easily damaged and manufacturing will be difficult.

Therefore, when a battery is manufactured by laminating the positive electrode sheet of this embodiment and the negative electrode sheet of this embodiment (the all-solid-state battery manufacturing method of the second embodiment described later), that is, both positive and negative electrode sheets have separator layers. In this case, the separator layer 19 of each electrode sheet has an average thickness of preferably 10 μm or less, more preferably 5 μm or less, particularly preferably 3 μm or less, and the thinnest portion preferably has a thickness of 0.5 μm. As described above, the thickness is more preferably 1 μm or more.

Further, in the case of manufacturing a battery by laminating the positive electrode sheet or the negative electrode sheet of the present embodiment and another electrode sheet having no separator layer (the all-solid-state battery manufacturing method of the third embodiment described later), The separator layer 19 of the electrode sheet has an average thickness of preferably 20 μm or less, more preferably 10 μm or less, particularly preferably 6 μm or less, and the thinnest portion preferably has a thickness of 1 μm or more, more preferably 2 μm. That is all.

The solution supply step S14 is performed by supplying a polymer solid electrolyte solution from above the inorganic solid electrolyte layer and permeating the active material layer and the inorganic solid electrolyte layer. The polymer solid electrolyte solution contains a polymer compound that serves as a skeleton of the polymer solid electrolyte after polymerization, and a lithium salt, and optionally contains a crosslinking agent and a polymerization initiator so that an appropriate viscosity is obtained by an organic solvent. Diluted.

The polymer solid electrolytes 18 and 21 contain a lithium salt in the polymer. As the polymer, polyethylene oxide (PEO), polypropylene oxide (PPO), a copolymer thereof, or the like can be used. Preferably, the polymer molecules are cross-linked, or the main skeleton of the polymer is graft-polymerized with another polymer or oligomer. This is to prevent the ionic conductivity from decreasing due to the crystallization of the polymer. Examples of the lithium salt include lithium perchlorate (LiClO ₄ ), lithium hexafluorophosphate (LiPF ₆ ), lithium bis(trifluoromethanesulfonyl)imide (LiN(CF ₃ SO ₂ ), as in batteries having a liquid electrolyte. ₂ , abbreviated as LiTFSI below) and the like can be used. As the diluting solvent, an organic solvent having a low boiling point such as tetrahydrofuran (THF) or acetonitrile can be preferably used.

By using the solution containing the polymer compound before polymerization in this way, it becomes easy to fill the gap between the active material particles 17 and the inorganic solid electrolyte particles 20 with the polymer solid electrolyte solution. The solid polymer electrolyte solution has a viscosity of preferably 1 to 100 mPa·s, more preferably 5 to 10 mPa·s. This is because if the viscosity is too high, the solution hardly penetrates into the active material layer and the inorganic solid electrolyte layer. Further, if the viscosity is too low, the content of the polymer compound is reduced and it is uneconomical and the density of the polymer solid electrolyte in the inorganic solid electrolyte layer is lowered to make it impossible to sufficiently maintain the ionic conductivity. ..

The polymer solid electrolytic solution may contain a plasticizer. In that case, the polymer solid electrolytes 18 and 21 contain a plasticizer, and the ionic conductivity is improved. However, the addition of the plasticizer reduces the strength of the solid polymer electrolyte, so the content of the plasticizer in the solid polymer electrolyte is preferably 10% by weight or less, more preferably 5% by weight or less. Particularly preferably, the solid polymer electrolyte does not contain a plasticizer. As the plasticizer, known materials such as carbonic acid esters such as ethylene carbonate (EC) and ethylmethyl carbonate (EMC), and a mixture thereof can be used.

The method of supplying the polymer solid electrolyte solution is not particularly limited, but preferably a non-contact coating method. The non-contact coating method is a method of supplying a solution without bringing a roll for transferring the solution, a nozzle for discharging the solution, or the like into contact with the inorganic solid electrolyte layer. Examples of the non-contact coating method include a spray method, a dispenser utilizing air pressure or electrostatic force, and various inkjet methods such as a piezo method. Above all, it is preferable to use a dispenser method utilizing an electrostatic force or an inkjet method. Even when supplying a low-viscosity solution, it is excellent in quantitative and in-plane uniformity of the supply amount, so that the solid polymer electrolyte solution is filled in the entire voids of the active material layer and the inorganic solid electrolyte layer, and the inorganic solid electrolyte layer surface This is because it is possible to form a thin film of the polymer solid electrolyte solution.

The polymer solid electrolyte solution is preferably filled in the gaps between the active material particles and the inorganic solid electrolyte particles over the entire area from the surface of the metal foil 12 to the surface of the inorganic solid electrolyte layer. Further, the polymer solid electrolyte solution preferably thinly covers the entire surface of the inorganic solid electrolyte layer. This is because a better bonding state can be obtained when the two electrode sheets are bonded together during battery production. Further, it is preferable that the polymer solid electrolyte solution fills the region 10D in the immediate vicinity of the heat-fusible resin frame, in which the active material particles and the inorganic solid electrolyte particles do not exist.

After the solvent of the polymer solid electrolyte solution is volatilized and dried, the polymer compound is polymerized in the curing step S15 to thereby form the gaps between the active material particles 17 in the active material layer and the inorganic solid electrolyte in the inorganic solid electrolyte layer. Polymer solid electrolytes 18 and 21 are formed in the spaces between the particles 20. Thereby, the separator layer 19 including the electrode 16 including the active material particles 17 and the solid polymer electrolyte 18 in the electrode that fills the gap, and the solid polymer electrolyte 21 in the separator layer that fills the gap and the inorganic solid electrolyte particles 20. Is completed. The polymer compound can be polymerized by heat curing, ultraviolet irradiation, electron beam irradiation, or a combination thereof. The method for polymerizing the polymer compound is preferably irradiation with ultraviolet rays. This is because the manufacturing equipment can be simplified.

The solution supply step may be performed in multiple times. For example, as shown in FIG. 17, after the step S12 of forming an active material layer, a step S14-1 of supplying a polymer solid electrolyte solution onto the active material layer to permeate the active material layer is provided to form an inorganic solid electrolyte layer. After the forming step S13, a step S14-2 may be provided in which a polymer solid electrolyte solution is supplied onto the inorganic solid electrolyte layer so as to permeate the inorganic solid electrolyte layer. Even if the solution supply step is performed twice in this way, the solid polymer electrolyte 18 contained in the electrode 16 and the solid polymer electrolyte 21 contained in the separator layer 19 are integrally formed by the curing step S15. .. Further, by supplying the solid polymer electrolyte solution in the active material layer and the solid polymer electrolyte in the inorganic solid electrolyte layer in separate steps, the supply viscosity of the solid polymer electrolyte solution in each layer and Since the permeability can be optimized, the bondability of the solid-solid interface in each layer can be easily improved, and the solid polymer electrolyte solution can be surely permeated to the bottom surface in the active material layer.

The total thickness of the electrode sheet 10 is preferably 50 μm or less, more preferably 40 μm or less. The electrode sheet of this embodiment is particularly suitable for manufacturing a thin film battery.

The effect of the electrode sheet manufacturing method of the present embodiment will be described again as follows.

Since the electrode sheet 10 uses a polymer solid electrolyte instead of a liquid electrolyte or a polymer gel electrolyte, there is no risk of liquid leakage. Further, the present inventor has noticed that even with a polymer solid electrolyte, if its effective thickness is sufficiently thin, charge/discharge characteristics close to those of a battery using an electrolytic solution or a polymer gel electrolyte can be obtained. .. By diluting the solid polymer electrolyte with a solvent, it becomes possible to cover between the particles of the electrode layer composed of the active material particles and the surface layer thereof with a very thin electrolyte. On the other hand, when the polymer solid electrolyte is formed so thinly, it is insufficient in penetration resistance and strength for lithium dendrite etc. to be used alone in the separator layer of the positive and negative electrode layers, but in recent years, it is more ionic than the polymer solid electrolyte. A variety of highly conductive inorganic solid electrolytes have been developed, and by using a polymer solid electrolyte and an inorganic solid electrolyte together in a separator layer, it has become possible to secure the insulation and strength of the separator layer. ..

Further, the polymer solid electrolyte after the polymerization cannot be impregnated between the particles, but according to the electrode sheet manufacturing method of the present embodiment, the gap between the active material particles 17 fixed by the binder and the inorganic solid. The polymer solid electrolyte is formed after the low-viscosity polymer solid electrolyte solution has penetrated into the gaps between the electrolyte particles 20. Therefore, it is easy to form the polymer solid electrolyte in the inorganic solid electrolyte layer, the interface between the inorganic solid electrolyte layer and the active material layer, and the entire area of the active material layer so as to fill the minute gaps between the particles. Thereby, a good contact state of the inorganic solid electrolyte particles 20 and the polymer solid electrolyte 21, the separator layer 19-electrode 16 interface, the active material particles 17 and the polymer solid electrolyte 18 is obtained, and a battery having low internal resistance is obtained. ..

Further, in the example of Patent Document 3, after forming an active material layer on a metal foil, an adhesive tape of the same size is attached and masked on the active material layer to form a heat-fusible resin film (this embodiment). (Corresponding to the heat-fusible resin film in the form) is bonded and cured, a cut is made in the heat-fusible resin film, and the inner portion is removed together with the adhesive tape. On the other hand, in the electrode sheet manufacturing method of the present embodiment, since the active material layer is applied to the inside of the preformed heat-fusible resin frame, the process is simplified and the adhesive tape is attached. -The active material layer is not damaged by the removal.

Further, in the electrode sheet manufacturing method of the present embodiment, when the active material layer is formed by screen printing or the like, a region 10D in which the active material particles 17 and the inorganic solid electrolyte particles 20 do not exist in the immediate vicinity of the heat-fusible resin frame 13 is formed. .. However, by filling the area 10D with the polymer solid electrolyte solution, the area 10D is occupied by the hard polymer solid electrolyte in the completed electrode sheet 10, and the area 10D does not become a void. Further, unlike the case of using a liquid electrolytic solution, the electrode 16 and the separator layer 19 adjacent to the region 10D do not collapse and the battery structure is destroyed during use of the battery. Further, unlike the case of using an electrolytic solution or a gel solid electrolyte, even if the heat-fusible resin frame 13 is heated for heat-sealing at the time of battery production, the latest reaction between the polymer solid electrolyte and the active material, etc. Is unlikely to occur.

As a modified example of the present embodiment, preferably, in step S12 of forming the active material layer, the applied electrode mixture further contains inorganic solid electrolyte particles. As a result, referring to FIG. 3, the electrode 26 of the manufactured electrode sheet 25 has the active material particles 17, the inorganic solid electrolyte particles 27, and the polymer solid filling the gaps between the active material particles 17 and the inorganic solid electrolyte particles 27. And an electrolyte 18. As a result, the mobility of electric charges moving in the gaps of the active material particles 17 is improved, and the internal resistance of the electrode is further reduced. As the inorganic solid electrolyte 27 contained in the electrode 26, particles such as LLT, LATP, LAGP and the like can be used as in the inorganic solid electrolyte 20 contained in the separator layer 19. Preferably, the same compound is used for the inorganic solid electrolyte 27 and the inorganic solid electrolyte 20.

As another modification of this embodiment, the heat-fusible resin frame 13 may be formed after forming the active material layer. In that case, the electrode sheet manufacturing method S10B is performed by referring to FIG.
(S11B) a step of preparing a metal foil 12 having no heat-fusible resin frame,
(S12) a step of forming an active material layer on the metal foil,
(S13) a step of forming an inorganic solid electrolyte layer on the active material layer,
(S14) a solution supplying step of supplying a polymer solid electrolyte solution from above the inorganic solid electrolyte layer to permeate the active material layer and the inorganic solid electrolyte layer;
(S15) a curing step of polymerizing the polymer compound,
(S11C) a step of forming the heat-fusible resin frame 13 around the active material layer on the metal foil,
Have.

The step of forming the heat-fusible resin frame S11C can be performed after the active material layer forming step S12, the inorganic solid electrolyte layer forming step S13, the solution supplying step S14, or the curing step S15. When the heat-fusible resin frame 13 is formed after forming the active material layer and the like as described above, the heat-fusible resin frame is preferably formed by inkjet printing or screen printing. This is because it is difficult to damage the already formed active material layer and the like.

Next, an all-solid-state lithium-ion battery according to the second embodiment of the present invention and a method for manufacturing the same will be described with reference to FIGS. 5 and 6.

With reference to FIG. 5, in the all-solid-state battery 100 of the present embodiment, the positive electrode sheet 30 manufactured by the method of the first embodiment and the negative electrode sheet 40 manufactured by the method of the first embodiment have respective separator layers 39. , 49 are laminated so that they are in contact with each other. The separator layer 109 of the all-solid-state battery is composed of the separator layer 39 of the positive electrode sheet and the separator layer 49 of the negative electrode sheet. Then, the heat-fusible resin frame 33 of the positive electrode sheet and the heat-fusible resin frame 43 of the negative electrode sheet are heat-fused at the broken line portion (33A) in FIG. 5 to form the heat-fusible resin wall 103. There is. The heat-fusible resin wall 103 surrounds and seals the outer periphery of the positive electrode 36, the separator layer 109, and the negative electrode 46.

The all-solid-state battery manufacturing method S100 of the present embodiment will be described with reference to FIG.
(S10) a step of manufacturing the positive electrode sheet 30 by the method of the first embodiment,
(S10) a step of manufacturing the negative electrode sheet 40 by the method of the first embodiment,
(S106) a step of stacking the positive electrode sheet and the negative electrode sheet,
(S108) a sealing step of heat-sealing the heat-fusible resin frames of the positive electrode sheet and the negative electrode sheet.

The heat-fusible resin frame 33 of the positive electrode sheet 30 and the heat-fusible resin frame 43 of the negative electrode sheet 40 are formed in the same shape and the same size so that the whole can be overlapped. Since the positive electrode sheet 30 is manufactured by the method of the first embodiment, the solid polymer electrolyte in the positive electrode 36 is formed integrally with the solid polymer electrolyte in the separator layer in the portion of the separator layer 109 that contacts the positive electrode. In addition, since the negative electrode sheet 40 is manufactured by the method of the first embodiment, the solid polymer electrolyte in the negative electrode 46 is formed integrally with the solid polymer electrolyte in the separator layer of the portion of the separator layer 109 that contacts the negative electrode. ..

In the superposing step S106, the positive electrode sheet 30 and the negative electrode sheet 40 are superposed so that the respective separator layers 39, 49 are in contact with each other, that is, the respective heat-fusible resin frames 33, 43 are joined. Preferably, the surface layer of either or both of the separator layer 39 of the positive electrode sheet 30 and the separator layer 49 of the negative electrode sheet 40, for example, after softening a range within 1 μm from the surface with a plasticizer, the positive electrode sheet and the negative electrode sheet are bonded together. .. This improves the bonding state of the separator layer of the positive electrode sheet and the separator layer of the negative electrode sheet, and reduces the internal resistance of the battery. As the plasticizer, an organic solvent such as ethylene carbonate (EC), propylene carbonate (PC), ethylmethyl carbonate (EMC), or a mixture thereof can be used.

In the sealing step S108, the heat-fusible resin frame 33 of the positive electrode sheet and the heat-fusible resin frame 43 of the negative electrode sheet are heat-fused at the broken line portion (33A) to form the heat-fusible resin wall 103. The positive electrode 36, the separator layer 109, and the negative electrode 46 are surrounded and sealed.

Also in this embodiment, the same modifications as in the first embodiment are possible. For example, in the step S12 of forming the positive electrode and/or the negative electrode active material layer, the electrode mixture to be coated may further contain inorganic solid electrolyte particles. The heat-fusible resin frames 33 and 43 may be formed after forming the active material layer and the inorganic solid electrolyte layer. That is, in FIG. 6, as the manufacturing process of the positive electrode sheet and/or the negative electrode sheet, step S10B shown in FIG. 4 may be adopted instead of step S10.

Next, an all-solid-state lithium-ion battery according to the third embodiment of the present invention and a method for manufacturing the same will be described with reference to FIGS.

Referring to FIG. 7, the all-solid-state battery 110 of the present embodiment is manufactured by the same method as in the first embodiment and the positive electrode sheet 30 manufactured by the method of the first embodiment, but without providing the separator layer. The negative electrode sheet 50 has a structure in which the heat-fusible resin frames 33 and 53 are laminated so as to be bonded to each other.

Referring to FIG. 8, the negative electrode sheet 50 has the same structure as the electrode sheet according to the first embodiment, but does not have a separator layer composed of inorganic solid electrolyte particles and polymer solid electrolyte. The negative electrode sheet 50 is configured by laminating the negative electrode metal foil 52 and the negative electrode 56 in this order. The negative electrode metal foil has a heat-fusible resin frame 53 formed on the peripheral portion of one surface thereof, and a heat-resistant resin layer 54 laminated on the opposite surface thereof, and the metal foil 52 is formed on a part of the heat-resistant resin layer 54. An exposed portion 55 is formed to expose. The negative electrode 56 is formed inside the heat-fusible resin frame 53. The negative electrode 56 includes negative electrode active material particles 57 and a solid polymer electrolyte 58 in the negative electrode that fills the gaps between them.

Returning to FIG. 7, the separator layer 119 of the all-solid-state battery 110 is composed of the separator layer 39 of the positive electrode sheet 30. Then, the heat-fusible resin frame 33 of the positive electrode sheet and the heat-fusible resin frame 53 of the negative electrode sheet 50 are heat-fused at the broken line portion (33A) to form the heat-fusible resin wall 113. The heat-fusible resin wall 113 surrounds and seals the outer periphery of the positive electrode 36, the separator layer 119, and the negative electrode 56.

The all-solid-state battery manufacturing method S110 of the present embodiment will be described with reference to FIG.
(S10) a step of manufacturing the positive electrode sheet 30 by the method of the first embodiment,
(S50) a step of manufacturing the negative electrode sheet (second electrode sheet) 50,
(S106) a step of stacking the positive electrode sheet and the negative electrode sheet,
(S108) a sealing step of heat-sealing the heat-fusible resin frames of the positive electrode sheet and the negative electrode sheet.

Since the positive electrode sheet 30 is manufactured by the method of the first embodiment, the solid polymer electrolyte in the positive electrode 36 is formed integrally with the solid polymer electrolyte in the separator layer in the portion of the separator layer 119 that contacts the positive electrode.

The manufacturing process S50 of the negative electrode sheet 50 includes
(S11) a step of preparing a metal foil 52 having a heat-fusible resin frame 53 formed on one surface,
(S12) a step of forming an active material layer on the metal foil,
(S54) A solution supplying step of supplying a solid polymer electrolyte solution from above the active material layer to permeate the active material layer,
(S55) a curing step of polymerizing the polymer compound.

In step S50 of manufacturing the negative electrode sheet 50, the step of preparing the metal foil 52 and the step of forming the negative electrode active material layer on the metal foil are the same as step S11 and step S12 in the first embodiment, respectively.

The solution supply step S54 is similar to the solution supply step S14 in the first embodiment. However, in step S14 of the first embodiment, the polymer solid electrolyte solution is supplied from above the inorganic solid electrolyte layer, whereas in step S54 of the present embodiment, since the inorganic solid electrolyte layer does not exist, the negative electrode active material layer The difference is that the solid polymer electrolyte solution is supplied from above. The solid polymer electrolyte solution is preferably filled in the gaps of the negative electrode active material particles 57 over the entire area from the surface of the metal foil 52 to the surface of the negative electrode active material layer. Similarly, it is preferable to fill the region 50D in the immediate vicinity of the functional resin frame 53 where the negative electrode active material particles 57 do not exist.

The curing step S55 for polymerizing the polymer compound is the same as the curing step S15 in the first embodiment. However, in the first embodiment, the irradiation target has an inorganic solid electrolyte layer, whereas in step S55 of the present embodiment, there is no inorganic solid electrolyte layer, which is a difference.

Step S106 of stacking the positive electrode sheet 30 and the negative electrode sheet 50, and heat-bonding the heat-fusible resin frame 33 of the positive electrode sheet and the heat-fusible resin frame 53 of the negative electrode sheet to form the heat-fusible resin wall 113. The sealing step S108 of enclosing and sealing the outer periphery of the positive electrode 36, the separator layer 119, and the negative electrode 56 is the same as in the second embodiment.

In the present embodiment, the positive electrode sheet 30 was manufactured by the method of the first embodiment and joined to the negative electrode sheet 50 having no separator layer. On the contrary, the negative electrode sheet was manufactured by the method of the first embodiment. It may be manufactured and joined to a positive electrode sheet having no separator layer.

Also in this embodiment, the same modifications as those of the first and second embodiments are possible. For example, in the step S12 of forming the positive electrode and/or the negative electrode active material layer, the electrode mixture to be coated may further contain inorganic solid electrolyte particles. The heat-fusible resin frame 33 may be formed after forming the active material layer and the like. That is, in FIG. 9, as the manufacturing process of the positive electrode sheet 30, step S10B shown in FIG. 4 may be adopted instead of step S10. Similarly, the heat-fusible resin frame 53 may be formed after forming the active material layer and the like. That is, in FIG. 9, as the manufacturing process of the negative electrode sheet 50, step S50B shown in FIG. 10 may be adopted instead of step S50.

Next, an all-solid-state lithium-ion battery according to the fourth embodiment of the present invention and a method for manufacturing the same will be described with reference to FIGS. 11 and 12.

With reference to FIG. 11, the all-solid-state battery 120 of this embodiment has the same structure as the all-solid-state battery 100 of the second embodiment. However, the all-solid-state battery 120 of the present embodiment is different from the all-solid-state battery 100 of the second embodiment in that the entire polymer solid electrolyte in the battery is integrally formed.

The lower side of FIG. 11 is the first sheet and the upper side is the second sheet. In the all-solid-state battery 120, the first heat-resistant resin layer 64, the first metal foil 62, the first electrode 66, the separator layer 129, and the second electrode 76. , The second metal foil 72, and the second heat resistant resin layer 74 are laminated in this order. The first electrode and the second electrode have opposite polarities. The first electrode may be the positive electrode and the second electrode may be the negative electrode, or vice versa. The heat-fusible resin wall 123 surrounds the outer circumferences of the electrodes 66 and 76 and the separator layer 129 to bond the first metal foil 62 and the second metal foil 72. Then, the solid polymer electrolytes in the first electrode 66, the separator layer 129, and the second electrode 76 are integrally formed.

The all-solid-state battery manufacturing method S120 of the present embodiment will be described with reference to FIG.
(S60) a step of manufacturing the first sheet 60,
(S60) a step of manufacturing the second sheet 70,
(S126) a step of stacking the positive electrode sheet and the negative electrode sheet,
(S127) a curing step of polymerizing the polymer compound,
(S128) a sealing step of heat-sealing the heat-sealable resin frames of the first sheet and the second sheet.

The first sheet manufacturing step S60 and the second sheet manufacturing step S70 are the same as the electrode sheet manufacturing step S10 of the first embodiment, but do not include a curing step (step S15 of FIG. 2) for polymerizing a polymer compound. Different. In the present embodiment, the superimposing step S126 superimposes the first sheet 60 and the second sheet 70 each containing an unpolymerized polymer solid electrolyte solution, and then polymerizes the polymer compound (S127).

The curing step S127 can be performed by heat curing, electron beam irradiation, or a combination thereof. In the case of electron beam irradiation, the electron beam is preferably irradiated from the metal foil side of the first metal foil 62 and the second metal foil 72 made of a metal having a small atomic number. For example, when the first metal foil is an aluminum foil and the second metal foil is a copper foil, the electron beam is irradiated from the aluminum foil side. This is because the electron beam is easily transmitted.

The sealing step S128 can be performed similarly to the sealing step S108 of the second and third embodiments. The sealing step may be performed simultaneously with the curing step S127, but it is preferably performed after the curing step. This is because it is possible to prevent inclusion of outgas or the like generated in the polymerization process of the polymer compound.

Also in this embodiment, the same modifications as those of the first to third embodiments are possible. For example, the first electrode 66 and/or the second electrode 76 may include inorganic solid electrolyte particles. Further, the first heat-fusible resin frame 63 may be formed after forming the active material layer and the like. Specifically, in the first sheet manufacturing step S60 of FIG. 12, the metal foil 62 on which the heat-fusible resin frame is not formed is prepared, and after the active material layer forming step S12 and the inorganic solid electrolyte layer forming step S13. Alternatively, the first heat-fusible resin frame 63 may be formed after the solution supply step S14. The same applies to the formation of the second heat-fusible resin frame 73 of the second sheet. Further, as in the third embodiment, either the first sheet 60 or the second sheet 70 may not have the inorganic solid electrolyte layer.

According to this embodiment, the entire polymer solid electrolyte inside the all-solid-state battery 120 is integrally formed, so that the internal resistance of the battery can be further reduced.

Next, an all-solid-state lithium-ion battery that is a fifth embodiment of the present invention and a method for manufacturing the same will be described with reference to FIGS.

With reference to FIG. 13, the all-solid-state battery 130 of the present embodiment has the same structure as the all-solid-state battery 120 of the fourth embodiment.

In the all-solid-state battery 130, the first heat resistant resin layer 84, the first metal foil 82, the first electrode 86, the separator layer 89, the second electrode 92, the second metal foil 96, and the second heat resistant resin layer 98 are arranged in this order. It is stacked. The first electrode and the second electrode have opposite polarities. The first electrode may be the positive electrode and the second electrode may be the negative electrode, or vice versa. The heat-fusible resin wall 133 surrounds the outer circumferences of the electrodes 86 and 92 and the separator layer 89 to bond the first metal foil 82 and the second metal foil 96. Then, the solid polymer electrolytes in the first electrode 86, the separator layer 89, and the second electrode 92 are integrally formed.

The all-solid-state battery manufacturing method S130 of this embodiment will be described with reference to FIG.
(S11) a step of preparing a first metal foil 82 having a first heat-fusible resin frame 83 formed on one surface,
(S12) a step of forming a first active material layer on the first metal foil,
(S13) a step of forming an inorganic solid electrolyte layer on the first active material layer,
(S82) a step of forming a second active material layer on the inorganic solid electrolyte layer,
(S84) A solution supplying step of supplying a polymer solid electrolyte solution from above the second active material layer to permeate the first active material layer, the inorganic solid electrolyte layer and the second active material layer,
(S85) a curing step of polymerizing the polymer compound,
(S136) a step of stacking a second metal foil 96 having a second heat-fusible resin frame 97 formed on one side,
(S138) A sealing step of heat-sealing the first heat-fusible resin frame 83 and the second heat-fusible resin frame 97.

The step of preparing the first metal foil 82, the step of forming the first active material layer, and the step of forming the inorganic solid electrolyte layer are the same as step S11, step S12, and step S13 in the first embodiment, respectively.

The step S82 of forming the second active material layer on the inorganic solid electrolyte layer can be performed in the same manner as the step S12 of forming the first active material layer.

The solution supply step S84 is the same as the solution supply step S14 in the first embodiment. However, in step S14 in the first embodiment, the polymer solid electrolyte solution is supplied from above the inorganic solid electrolyte layer, whereas in step S84 of the present embodiment, the second active material layer formed on the inorganic solid electrolyte is supplied. The difference is that the solid polymer electrolyte solution is supplied from above. The solid polymer electrolyte solution is preferably filled over the entire area from the surface of the metal foil 82 to the surface of the second active material layer. The solid polymer electrolyte solution is provided in the immediate vicinity of the heat fusible resin frame 83. Similarly, it is preferable to fill the region 130D where the active material particles/inorganic solid electrolyte particles do not exist.

The curing step S85 is also similar to the curing step S15 in the first embodiment. However, in step S15 of the first embodiment, the irradiation target has an active material layer and an inorganic solid electrolyte layer, whereas in step S85 of the present embodiment, the irradiation target further has a second active material layer. Different. By this curing step, the solid polymer electrolytes 88, 91 and 94 in the first electrode 86, the separator layer 89 and the second electrode 92 are integrally formed. Then, the first electrode 86 including the first active material particles 87 and the first solid polymer solid electrolyte 88 filling the gap, the inorganic solid electrolyte particles 90, and the solid polymer electrolyte 91 in the separator layer filling the gap are provided. The second electrode 92 including the separator layer 89 containing the second active material particles 93 and the second solid polymer electrolyte in the second electrode 94 filling the gaps between the second active material particles 93 is completed.

The step S136 of stacking the second metal foils is the same as in the second embodiment. In the superposing step S136, the second metal foil is placed on the second electrode 92 so that the first heat-fusible resin frame 83 and the second heat-fusible resin frame 97 are bonded to each other.

The sealing step S138 is also the same as in the second embodiment. In the sealing step, the first heat-fusible resin frame 83 and the second heat-fusible resin frame 97 are heat-welded at the broken line portion (83A) in FIG. 13 to form the heat-fusible resin wall 133, The outer circumferences of the first electrode 86, the separator layer 89 and the second electrode 92 are surrounded and sealed.

Also in this embodiment, the same modifications as those of the first to fourth embodiments are possible. For example, the first electrode and the second electrode may further include inorganic solid electrolyte particles. Further, the first heat-fusible resin frame 83 may be formed after forming the active material layer and the like. Specifically, in FIG. 14, the first metal foil 82 on which the heat-fusible resin frame is not formed is prepared, and one of the steps from after the first active material layer forming step S12 to the overlapping step S136 is performed. At the stage, the first heat-fusible resin frame 83 may be formed.

Further, the order of the curing step and the superposing step may be exchanged. That is, referring to FIG. 15, after the solution supply step S84, the second metal foil 96 is overlapped without performing the curing step, and then the curing step S137 is performed. At the stage where the second metal foils are superposed, the polymer solid electrolyte solution is unpolymerized. The curing step S137 can be performed in the same manner as the curing step S127 of the fourth embodiment.

The effects of the all-solid-state battery manufacturing methods of the second to fifth embodiments will be described again below.

Since the manufactured all-solid-state battery uses a polymer solid electrolyte instead of a liquid electrolyte or a polymer gel electrolyte, there is no risk of liquid leakage. Moreover, since the solid polymer electrolyte fills the gaps between the active material particles, the contact state between the solid polymer electrolyte and the active material particles is good, and a battery having low internal resistance can be obtained. Furthermore, since the polymer solid electrolyte in either or both electrodes is formed integrally with the polymer solid electrolyte in at least the portion in contact with the electrode in the separator layer, the interface resistance between the electrode and the separator layer is suppressed. A battery with low internal resistance can be obtained. Further, since the separator layer contains an inorganic solid electrolyte having higher ionic conductivity and hardness than the polymer solid electrolyte, the ionic conductivity and strength of the separator layer can be compatible at a high level.

Further, when the solid polymer electrolyte solution is supplied after forming the heat-fusible resin frame, the produced all-solid-state battery has a region where the active material particles and the inorganic solid electrolyte particles in the immediate vicinity of the heat-fusible resin frame do not exist. Is occupied by the polymer solid electrolyte, the battery structure during use of the battery is unlikely to collapse.

Next, it was confirmed by experiments that a laminate composed of an electrode composed of active material particles and a polymer solid electrolyte and a separator layer composed of inorganic solid electrolyte particles and a polymer solid electrolyte functions as a battery.

Lithium cobalt oxide (LiCoO ₂ , Toshima Manufacturing Co., Ltd., product number: LiCoO ₂ fine powder, average particle size 1 μm) as a positive electrode active material, Ketjen black (KB) as a conduction aid, and polyvinylidene fluoride (PVdF) as a binder. N methyl 2 pyrrolidone (NMP) was added to a positive electrode mixture in which 95:2:3 was mixed at a weight ratio of 52% by weight to form a paste. This positive electrode material mixture paste was applied on an aluminum foil having a thickness of 20 μm by screen printing in a size of 50 mm×50 mm and dried at 80° C. to 120° C. for 2 hours to form a positive electrode active material layer having a thickness of 15 μm. Formed. The electrolyte mixture was mixed with LAGP:PVdF=97:3 (weight ratio), and NMP was added so that the solid content ratio became 69% by weight to form a paste. This electrolyte mixture paste was applied on the positive electrode active material layer by screen printing to a size of 56 mm×56 mm, dried at 80° C. for 20 minutes, and the positive electrode active material layer had an inorganic solid electrolyte layer with a thickness of 10 μm. Was formed. The polymer solid electrolyte solution was prepared by mixing polyethylene oxide (PEO) as a polymer compound with a photopolymerization initiator and LiTFS as a lithium salt, and adding NMP as a solvent to adjust the viscosity. This polymer solid electrolyte solution is supplied to the surface of the inorganic solid electrolyte layer by an ink jet method, and allowed to stand to fill the entire voids of the positive electrode active material layer and the inorganic solid electrolyte layer, and then irradiated with ultraviolet rays to cross-link the polymer compound. Let As a result, a separator layer was formed on the positive electrode and the positive electrode active material layer. The thickness of the separator layer was 13 μm, that is, the region of the surface layer 3 μm did not contain the inorganic solid electrolyte particles, but contained only the polymer solid electrolyte. Through the above steps, a positive electrode sheet having an electrode and a separator layer was produced.

Artificial graphite (Showa Denko KK, product number: SCMG, average particle size 5 μm) as a negative electrode active material, KB as a conductive aid, and PVdF as a binder in a weight ratio of 96:1:3. Then, NMP was added to form a paste so that the solid content ratio was 50% by weight. This negative electrode mixture paste was applied by screen printing on a copper foil having a thickness of 15 μm to a size of 50 mm×50 mm and dried at 80° C. to 120° C. for 2 hours to form a negative electrode active material layer having a thickness of 15 μm. Formed. The same solid polymer electrolyte solution as described above and the surface of the negative electrode active material layer were supplied by an inkjet method, the whole area of the negative electrode active material layer was filled, and then ultraviolet rays were irradiated to crosslink the polymer compound. As a result, a polymer solid electrolyte phase was formed between the negative electrode active material particles, and a polymer solid electrolyte layer having a thickness of 5 μm was formed on the negative electrode active material layer. Through the above steps, a negative electrode sheet having no separator layer was produced.

A plasticizer was spread on the surface of the separator layer of the positive electrode sheet and then laminated with the negative electrode sheet to prepare a battery of Experimental Example.

FIG. 16 shows the result of the charge/discharge test carried out under the conditions of constant current constant voltage charge of current 100 μA, voltage 4.2 V, charge time 60 minutes, discharge current 100 μA, constant current discharge of final voltage 1.0 V. Show. From FIG. 16, it was confirmed that the battery of the experimental example stably performs charge/discharge operation.

Next, it was confirmed that by forming a polymer solid electrolyte between the inorganic solid electrolyte particles of the separator layer, lithium ion conductivity is effectively exhibited between the inorganic solid electrolyte particles.

After forming an inorganic solid electrolyte layer using polyvinylidene fluoride (PVdF) as a binder on an aluminum foil, a polymer solid electrolyte solution is permeated into the inorganic solid electrolyte layer, and the counter electrode of the aluminum foil is placed in contact therewith. After that, the polymer in the polymer solid electrolyte solution was crosslinked and cured by a polymerization reaction to form an all-solid electrolyte layer in which the polymer solid electrolyte penetrated between the inorganic solid electrolyte particles, and the ionic conductivity thereof was evaluated. Here an inorganic solid electrolyte of approximately 1μm particle size in the particle _{Li 1 + x Al y Ge 2} -y (PO 4) 3 (LAGP), polymer solid electrolyte solution height the backbone of the polymer solid electrolyte after polymerization It contained a molecular compound, a lithium salt, a crosslinking agent, and a polymerization initiator, and was diluted with an organic solvent to have an appropriate viscosity.

The lithium ion conductivity at room temperature of the obtained all-solid-state electrolyte layer was measured using the AC impedance method. The ionic conductivity σ was calculated by the following formula.
σ=L/(R×S)
In the formula, σ is ionic conductivity (unit: S/cm), L is distance between electrodes (unit: cm), R is resistance (unit: Ω) calculated from real impedance intercept of Cole-Cole plot, and S is sample. Area (unit: cm ² ). The results are shown in Table 1.

In Table 1, while the ionic conductivity of the inorganic solid electrolyte layer before applying the solid polymer electrolyte solution was 2.0×10 ⁻⁷ S/cm, polymerization was performed after impregnation with the solid polymer electrolyte solution. The ionic conductivity of the all-solid electrolyte layer obtained by curing was 2.7×10 ⁻⁵ S/cm. This is 5.4×10 ⁻² S/5 μm when converted to a thickness of the all-solid electrolyte layer of 5 μm, and even if the all-solid electrolyte layer does not contain an electrolytic solution, it is an inorganic substance with a polymer solid electrolyte. It was confirmed that by filling the spaces between the particles of the solid electrolyte, good lithium ion conductivity was exhibited. The ionic conductivity of the solid polymer electrolyte alone used at this time was 6.4×10 ⁻⁵ S/cm.

The present invention is not limited to the above-mentioned embodiment, and various modifications can be made within the scope of the technical idea thereof.

10, 30, 40, 50 Electrode sheet; 10D Area where active material particles and inorganic solid electrolyte particles in the immediate vicinity of the heat-fusible resin frame do not exist; 12, 32, 42, 52 metal foil; 13, 33, 43, 53 heat Fusing resin frame; 14, 34, 44, 54 Heat-resistant resin layer; 15 Exposed part; 16, 36, 46 Electrode; 17 Active material particles; 18 (in electrode) Polymer solid electrolyte; 19, 39, 49 Separator Layer: 20 Inorganic solid electrolyte particles; 21 (within separator layer) polymer solid electrolyte; 25 electrode sheet; 26 electrode; 27 second inorganic solid electrolyte particles; 33A fused surface of heat-fusible resin frame; 60 first sheet 70 second sheet; 62, 72 metal foil; 63, 73 heat-fusible resin frame; 63A fusing surface of heat-fusible resin frame; 64, 74 heat-resistant resin layer; 65, 75 exposed portion; 66, Reference numeral 76 electrode; 67, 77 active material particles; 68, 78 (in electrode) solid polymer electrolyte; 69, 79 separator layer; 82 first metal foil; 83 first heat-fusible resin frame; 84 first heat-resistant resin Layer: 85 1st exposed part; 86 1st electrode; 87 1st active material particle; 88 (in 1st electrode) polymer solid electrolyte; 89 separator layer; 90 inorganic solid electrolyte particle; 91 (in separator layer) polymer Solid electrolyte; 92 Second electrode; 93 Second active material particles; 94 (inside second electrode) Polymer solid electrolyte; 95 Second current collector sheet; 96 Second metal foil; 97 Second heat-fusible resin frame 98 second heat-resistant resin layer; 99 second exposed portion; 100, 110, 120, 130 all-solid battery; 100D, 110D, 120D, 130D active material particles and inorganic solid electrolyte particles in the immediate vicinity of the heat-fusible resin wall; 103, 113, 123, 133 heat-fusible resin wall; 109, 119, 129, 139 Separator layer

Claims (22)

A step of preparing a metal foil having a heat-fusible resin frame formed on one surface,
Inside the heat-fusible resin frame on the metal foil, a step of applying an electrode mixture containing active material particles to form an active material layer,
A step of forming an inorganic solid electrolyte layer containing inorganic solid electrolyte particles on the active material layer,
Supplying a polymer solid electrolyte solution containing a polymer compound and an alkali metal salt, a solution supply step of permeating the active material layer and the inorganic solid electrolyte layer,
After the solution supply step, by polymerizing the polymer compound, a curing step of integrally forming a polymer solid electrolyte between the active material particles and between the inorganic solid electrolyte particles,
A method for manufacturing an electrode sheet having the following. A step of preparing a metal foil,
A step of forming an active material layer by applying an electrode mixture containing active material particles on the metal foil;
A step of forming an inorganic solid electrolyte layer containing inorganic solid electrolyte particles on the active material layer,
Supplying a polymer solid electrolyte solution containing a polymer compound and an alkali metal salt, a solution supply step of permeating the active material layer and the inorganic solid electrolyte layer,
After the solution supply step, by polymerizing the polymer compound, a curing step of integrally forming a polymer solid electrolyte between the active material particles and between the inorganic solid electrolyte particles,
Performed at any stage from after the active material layer forming step to after the curing step, around the active material layer on the metal foil, a step of forming a heat-fusible resin frame,
A method for manufacturing an electrode sheet having the following. The solution supply step,
After forming the active material layer, supplying the polymer solid electrolyte solution on the active material layer to permeate the active material layer, and after forming the inorganic solid electrolyte layer, the inorganic solid electrolyte layer Comprising two steps of supplying the polymer solid electrolyte solution and permeating into the inorganic solid electrolyte layer.
The electrode sheet manufacturing method according to claim 1. The metal foil has a heat resistant resin layer on the surface opposite to the surface on which the active material layer is formed,
The electrode sheet manufacturing method according to claim 1. In the step of forming the active material layer, the electrode mixture further contains the inorganic solid electrolyte particles,
The electrode sheet manufacturing method according to claim 1. In the step of forming the active material layer, the electrode mixture is applied by screen printing or gravure printing,
The electrode sheet manufacturing method according to claim 1. The solution supplying step is a step of supplying the polymer solid electrolyte solution onto the inorganic solid electrolyte layer by a non-contact coating method,
The electrode sheet manufacturing method according to claim 1. A first electrode including a first metal foil, a first active material particle, and a first polymer solid electrolyte in the electrode filling the space between the first active material particle, a gap between the inorganic solid electrolyte particle and the inorganic solid electrolyte particle A separator layer containing a polymer solid electrolyte in a separator layer for filling the second electrode, and a polymer in the second electrode having a polarity opposite to that of the first electrode and filling a gap between the second active material particles and the second active material particles. A second electrode including a solid electrolyte and a second metal foil are laminated in this order,
At least one of the first solid polymer electrolyte in the electrode and the second solid polymer electrolyte in the electrode is formed integrally with the solid polymer electrolyte in the separator layer in a portion in contact with the first or second electrode. ,
A heat-fusible resin wall that surrounds the outer peripheries of the first electrode, the separator layer, and the second electrode, and that bonds the first metal foil and the second metal foil,
All solid state battery. The first metal foil has a first heat resistant resin layer on the surface opposite to the first electrode, and/or the second metal foil has a second heat resistant resin on the surface opposite to the second electrode. Having layers,
The all-solid-state battery according to claim 8. The first solid polymer electrolyte in the electrode, the solid polymer electrolyte in the separator layer, and the solid polymer electrolyte in the second electrode are integrally formed,
The all-solid-state battery according to claim 8 or 9. A method of manufacturing the all-solid-state battery according to claim 8 or 9,
Manufacturing the first electrode sheet by the method according to any one of claims 1 to 7,
Manufacturing the 2nd electrode sheet which has a polarity opposite to the said 1st electrode sheet by the method in any one of Claims 1-7,
A step of stacking the first electrode sheet and the second electrode sheet so that the respective heat-fusible resin frames are joined to each other;
A sealing step of forming a heat-fusible resin wall by heat-fusing the heat-fusible resin frames of the first electrode sheet and the second electrode sheet to each other;
An all-solid-state battery manufacturing method having. A method of manufacturing the all-solid-state battery according to claim 8 or 9,
Manufacturing the first electrode sheet by the method according to any one of claims 1 to 7,
A step of producing a second electrode sheet having a polarity opposite to that of the first electrode sheet,
A step of preparing the second metal foil having a second heat-fusible resin frame formed on one surface thereof;
Forming a second active material layer containing the second active material particles on the second metal foil and inside the second heat-fusible resin frame;
A second solution supplying step of supplying a second polymer solid electrolyte solution containing a second polymer compound and the alkali metal salt to permeate the second active material layer;
A second curing step for forming the second polymer solid electrolyte between the second active material particles by polymerizing the second polymer compound;
Stacking the first electrode sheet and the second electrode sheet so that the heat-fusible resin frame of the first electrode sheet and the second heat-fusible resin frame are joined together,
A sealing step of heat-sealing the heat-fusible resin frame of the first electrode sheet and the second heat-fusible resin frame to form the heat-fusible resin wall;
An all-solid-state battery manufacturing method having. A method of manufacturing the all-solid-state battery according to claim 8 or 9,
Manufacturing the first electrode sheet by the method according to any one of claims 1 to 7,
A step of producing a second electrode sheet having a polarity opposite to that of the first electrode sheet,
A step of preparing the second metal foil,
Forming a second active material layer containing the second active material particles on the second metal foil;
A second solution supplying step of supplying a second polymer solid electrolyte solution containing a second polymer compound and the alkali metal salt to permeate the second active material layer;
A second curing step of forming the second polymer solid electrolyte between the second active material particles by polymerizing the second polymer compound;
The second thermal fusion bonding is performed at any stage from after the second active material layer forming step to after the second curing step, on the second metal foil and around the second active material layer. A second electrode sheet manufacturing step having a step of forming a conductive resin frame,
Stacking the first electrode sheet and the second electrode sheet so that the heat-fusible resin frame of the first electrode sheet and the second heat-fusible resin frame are joined together,
A sealing step of heat-sealing the heat-fusible resin frame of the first electrode sheet and the second heat-fusible resin frame to form the heat-fusible resin wall;
An all-solid-state battery manufacturing method having. A method for manufacturing the all-solid-state battery according to claim 10, comprising:
A step of preparing the first metal foil having a first heat-fusible resin frame formed on one surface thereof;
Forming a first active material layer containing the first active material particles on the first metal foil and inside the first heat-fusible resin frame;
Forming a first inorganic solid electrolyte layer containing first inorganic solid electrolyte particles on the first active material layer;
A first solution supplying step of supplying a polymer solid electrolyte solution containing a polymer compound and an alkali metal salt so as to permeate the first active material layer and the first inorganic solid electrolyte layer. When,
A step of preparing the second metal foil having a second heat-fusible resin frame formed on one surface thereof;
Forming a second active material layer containing second active material particles on the second metal foil and inside the second heat-fusible resin frame;
A second sheet manufacturing process including a second solution supplying process of supplying the polymer solid electrolyte solution to permeate the second active material layer.
Stacking the first sheet and the second sheet so that the first heat-fusible resin frame and the second heat-fusible resin frame are joined together,
A curing step of integrally forming a polymer solid electrolyte by polymerizing the polymer compound, between the first active material particles, between the first inorganic solid electrolyte particles and between the second active material particles;
A sealing step of heat-sealing the first heat-fusible resin frame and the second heat-fusible resin frame to form the heat-fusible resin wall;
An all-solid-state battery manufacturing method having. A method for manufacturing the all-solid-state battery according to claim 10, comprising:
A step of preparing a first metal foil,
Forming a first active material layer containing first active material particles on the first metal foil;
Forming a first inorganic solid electrolyte layer containing first inorganic solid electrolyte particles on the first active material layer;
A first solution supplying step of supplying a polymer solid electrolyte solution containing a polymer compound and an alkali metal salt so as to permeate the first active material layer and the first inorganic solid electrolyte layer;
It is carried out at any stage from after the first active material layer forming step to after the first solution supplying step, and a first layer is formed on the first metal foil and around the first active material layer. A first sheet manufacturing step having a step of forming a heat-fusible resin frame,
A step of preparing a second metal foil,
Forming a second active material layer containing second active material particles on the second metal foil;
A second solution supplying step of supplying the polymer solid electrolyte solution to permeate the second active material layer;
It is carried out at any stage from the step of forming the second active material layer to the step of supplying the second solution. A second sheet manufacturing step including a step of forming a heat-fusible resin frame,
Stacking the first sheet and the second sheet so that the first heat-fusible resin frame and the second heat-fusible resin frame are joined together,
A curing step of integrally forming a polymer solid electrolyte by polymerizing the polymer compound, between the first active material particles, between the first inorganic solid electrolyte particles and between the second active material particles;
A sealing step of heat-sealing the first heat-fusible resin frame and the second heat-fusible resin frame to form the heat-fusible resin wall;
An all-solid-state battery manufacturing method having. In the first solution supply step,
After forming the first active material layer, supplying the polymer solid electrolyte solution onto the first active material layer to permeate the first active material layer, and forming the first inorganic solid electrolyte layer After that, it comprises two steps of a step of supplying the polymer solid electrolyte solution onto the first inorganic solid electrolyte layer and permeating into the first inorganic solid electrolyte layer.
The method for manufacturing an electrode sheet according to claim 14 or 15. Further comprising a step of forming a second inorganic solid electrolyte layer containing second inorganic solid electrolyte particles on the second active material layer,
The second solution supply step is a step of supplying the polymer solid electrolyte solution to permeate the second active material layer and the second inorganic solid electrolyte layer,
In the curing step, by polymerizing the polymer compound, a high level is obtained between the first active material particles, the first inorganic solid electrolyte particles, the second inorganic solid electrolyte particles, and the second active material particles. It is a curing step that integrally forms a molecular solid electrolyte,
The all-solid-state battery manufacturing method according to any one of claims 14 to 16. In the second solution supply step,
After forming the second active material layer, supplying the polymer solid electrolyte solution onto the second active material layer to permeate the second active material layer, and forming the second inorganic solid electrolyte layer After that, it comprises two steps of supplying the polymer solid electrolyte solution onto the second inorganic solid electrolyte layer to permeate the second inorganic solid electrolyte layer.
The electrode sheet manufacturing method according to claim 17. A method for manufacturing the all-solid-state battery according to claim 10, comprising:
A step of preparing the first metal foil having a first heat-fusible resin frame formed on one surface thereof;
Forming a first active material layer containing first active material particles on the first metal foil and inside the first heat-fusible resin frame;
Forming an inorganic solid electrolyte layer containing inorganic solid electrolyte particles on the first active material layer;
Forming a second active material layer containing second active material particles on the inorganic solid electrolyte layer;
A solution supplying step of supplying a polymer solid electrolyte solution containing a polymer compound and an alkali metal salt to permeate the first active material layer, the inorganic solid electrolyte layer and the second active material layer,
A curing step of polymerizing the polymer compound to integrally form a polymer solid electrolyte between the first active material particles, between the inorganic solid electrolyte particles, and between the second active material;
The second metal foil, which is formed before or after the curing step and has the second heat-fusible resin frame formed on one surface thereof, is provided with the first heat-fusible resin frame and the second heat-fusible resin frame. Overlapping on the second active material layer so that
A sealing step of heat-sealing the first heat-fusible resin frame and the second heat-fusible resin frame to form the heat-fusible resin wall;
An all-solid-state battery manufacturing method having. A method for manufacturing the all-solid-state battery according to claim 10, comprising:
A step of preparing the first metal foil,
Forming a first active material layer containing first active material particles on the first metal foil;
Forming an inorganic solid electrolyte layer containing inorganic solid electrolyte particles on the first active material layer;
Forming a second active material layer containing second active material particles on the inorganic solid electrolyte layer;
A solution supplying step of supplying a polymer solid electrolyte solution containing a polymer compound and an alkali metal salt to permeate the first active material layer, the inorganic solid electrolyte layer and the second active material layer,
A curing step of polymerizing the polymer compound to integrally form a polymer solid electrolyte between the first active material particles, between the inorganic solid electrolyte particles, and between the second active material;
The first thermal fusion bonding is performed at any stage from the step of forming the first active material layer to the step of curing, and is provided on the first metal foil and around the first active material layer. Of forming a flexible resin frame,
Before or after the curing step and after the step of forming the first heat-fusible resin frame, the second metal foil having a second heat-fusible resin frame formed on one side thereof, A step of stacking the first heat-fusible resin frame and the second heat-fusible resin frame on the second active material layer so as to be bonded to each other;
A sealing step of heat-sealing the first heat-fusible resin frame and the second heat-fusible resin frame to form the heat-fusible resin wall;
An all-solid-state battery manufacturing method having. The solution supplying step may be performed at a plurality of stages after the step of forming the first active material layer, the step of forming the inorganic solid electrolyte layer, and the step of forming the second active material layer. A step of permeating the first active material layer, the inorganic solid electrolyte layer and the second active material layer by supplying a polymer solid electrolyte solution containing a molecular compound and an alkali metal salt,
The all-solid-state battery manufacturing method according to claim 19 or 20. The first metal foil has a first heat resistant resin layer on the surface opposite to the surface on which the first active material layer is formed, and/or the second metal foil is on the surface opposite to the second active material layer. Has a second heat resistant resin layer,
The all-solid-state battery manufacturing method according to any one of claims 12 to 21.

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