WO2017145657A1 - All-solid secondary battery, method for producing all-solid secondary battery, stacked green sheet for all-solid secondary battery, stacked green sheet with current collector foil for all-solid secondary battery, and continuous stacked green sheet for all-solid secondary battery - Google Patents

Abstract

In order to achieve an increase in the capacity of an all-solid secondary battery, the present invention provides an all-solid secondary battery that includes a stacked body obtained by stacking, in the following order, a positive electrode layer pellet sintered body (13), a solid electrolyte layer pellet sintered body (12), and a negative electrode layer pellet sintered body (11), wherein the quantity of a carbide per unit mass included in the positive electrode layer pellet sintered body (13), the quantity of the carbide per unit mass included in the solid electrolyte layer pellet sintered body (12), and the quantity of the carbide per unit mass included in the negative electrode layer pellet sintered body (11) are configured to satisfy: positive electrode layer > solid electrolyte layer; and negative electrode layer > solid electrolyte layer. This makes it possible to realize a high-capacity all-solid secondary battery in which high electron transfer resistance can be maintained in the solid electrolyte layer and low electron transfer resistance can be maintained in the positive electrode layer and the negative electrode layer, and the interface resistance between a metal current collector foil and the positive electrode layer and the metal current collector foil and the negative electrode layer is kept low.

Description

All solid state secondary battery, method for producing all solid state secondary battery, laminate green sheet for all solid state secondary battery, laminate green sheet with current collector foil for all solid state secondary battery, and all solid state secondary battery Continuous laminate green sheet

The present invention relates to a technique for an all solid state secondary battery.

As electronic devices such as personal computers, mobile phones typified by smartphones, digital cameras, and the like have advanced in functionality, electronic devices are required to be smaller while power consumption increases. For this reason, there is a demand for higher energy density in secondary batteries. High energy density is also required for household storage batteries that are stationary applications. Further, in recent years, along with the increase in demand for in-vehicle applications such as hybrid vehicles and electric vehicles, it is required to achieve both higher output density and higher energy density of the secondary battery. In addition, since an organic solvent is used in the electrolyte solution of the secondary battery, further safety improvement of the secondary battery is required from the viewpoint of preventing leakage of the electrolyte solution, ignition, and the like.

The most promising secondary battery that satisfies these requirements is an all-solid lithium ion secondary battery in which the entire configuration of the negative electrode, the electrolyte, and the positive electrode is made of a solid material. This all-solid-state lithium ion secondary battery is being developed as a battery having high energy density, high safety, and long life.
However, the all-solid-state lithium ion secondary battery currently in practical use is a very thin all-solid secondary battery, and its energy density is not high. Furthermore, since the positive electrode layer, the solid electrolyte layer, and the negative electrode layer are produced by a vapor deposition method or a sputtering method, it is necessary to produce them under a reduced pressure atmosphere, which is not suitable for increasing the area and mass production.

Therefore, a method for producing an all-solid-state lithium ion secondary battery by firing a green sheet of a positive electrode layer, a green sheet of a solid electrolyte layer, and a green sheet of a negative electrode layer has been studied. In addition, improvement in conductivity of the positive electrode layer and the negative electrode layer has been a problem, and methods such as Patent Document 1 and Patent Document 2 for improving conductivity are disclosed.
For example, in Patent Document 1, Sb ₂ O ₃ -doped SnO ₂ and SnO ₂ -doped In ₂ O ₃ are added as conductive assistants to the positive electrode layer and the negative electrode layer, respectively, for the purpose of improving the conductivity of the positive electrode layer and the negative electrode layer. Patents are disclosed.
In Patent Document 2, a positive electrode active material and a negative electrode active material coated with carbon are used for the purpose of improving the conductivity of the positive electrode layer and the negative electrode layer, and a certain amount of conductive auxiliary agent is added to the positive electrode layer and the negative electrode layer. Issued patents.

Japanese Patent No. 4845244 Japanese Patent No. 5602541

However, as shown in Patent Document 1, when Sb ₂ O ₃ -doped SnO ₂ and SnO ₂ -doped In ₂ O ₃ are used as conductive assistants, these conductive assistants are very expensive materials, so that the positive electrode layer And there is a concern about the cost increase of the negative electrode layer.
Moreover, as shown in Patent Document 2, when a carbon-coated positive electrode active material and negative electrode active material are used for the positive electrode layer and the negative electrode layer, there are concerns about an increase in manufacturing steps and cost increase.
The present invention has been made paying attention to the above-mentioned unsolved problems, and makes it possible to provide an all-solid-state secondary battery capable of increasing the capacity without increasing the manufacturing process and increasing the cost. The purpose is that.

According to one aspect of the present invention, in an all-solid-state secondary battery including a positive electrode layer, a solid electrolyte layer, and a negative electrode layer, the amount of carbide per unit mass contained in the positive electrode layer, the carbide per unit mass contained in the solid electrolyte layer There is provided an all-solid secondary battery in which the amount and amount of carbide per unit mass contained in the negative electrode layer satisfy the relationship of positive electrode layer> solid electrolyte layer and negative electrode layer> solid electrolyte layer.

According to one embodiment of the present invention, an all-solid-state secondary battery that exhibits a large capacity can be obtained.

It is a schematic diagram which shows an example (Example 1) of the all-solid-state secondary battery which concerns on one Embodiment of this invention. It is a schematic diagram which shows an example (Example 2) of the all-solid-state secondary battery which concerns on one Embodiment of this invention. It is a schematic diagram which shows an example (Example 3) of the all-solid-state secondary battery which concerns on one Embodiment of this invention. It is a schematic diagram which shows an example (Example 4) of the all-solid-state secondary battery which concerns on one Embodiment of this invention. It is a schematic diagram which shows an example (Example 5) of the all-solid-state secondary battery which concerns on one Embodiment of this invention.

Hereinafter, an all solid state secondary battery according to an embodiment of the present invention will be described with reference to the drawings.
The present invention is not limited to the embodiments described below, and modifications such as design changes can be made based on the knowledge of those skilled in the art, and such modifications have been added. Embodiments can also be included in the scope of embodiments of the present invention.

The all-solid-state secondary battery in one embodiment of the present invention has a configuration in which a stacked body in which a positive electrode layer, a solid electrolyte layer, and a negative electrode layer are stacked in this order is sandwiched between current collector layers from the positive electrode layer and negative electrode layer sides. The precursor of each of the positive electrode layer, the solid electrolyte layer, and the negative electrode layer contains a resin, and each of the precursors of the positive electrode layer, the solid electrolyte layer, and the negative electrode layer, or a laminate composed of the positive electrode layer, the solid electrolyte layer, and the negative electrode layer. By firing the body precursor or the laminate precursor with current collector foil, at least a part of the resin is carbonized.
The precursors of the positive electrode layer, the solid electrolyte layer, and the negative electrode layer are, for example, a positive electrode layer green sheet, a solid electrolyte layer green sheet, and a negative electrode layer green sheet.

The positive electrode layer green sheet and the negative electrode layer green sheet are prepared by mixing an active material and a solid electrolyte or glass that becomes a solid electrolyte after firing and a binder made of an organic resin together with a solvent to form a positive electrode slurry and a negative electrode slurry, and these are metal current collector foils It is formed by applying or printing on a transfer PET substrate or solid electrolyte layer green sheet and then drying. The method for preparing the positive electrode slurry and the negative electrode slurry is not particularly limited. Here, for the positive electrode layer green sheet and the negative electrode layer green sheet, a binder having a large amount of residual carbide in the carbonization treatment is used.

The solid electrolyte layer green sheet is a solid electrolyte slurry obtained by mixing a solid electrolyte or glass that becomes a solid electrolyte after firing and a binder made of an organic resin together with a solvent to form a solid electrolyte slurry, and these are positive electrode layer green sheet, negative electrode layer green sheet, or transfer It is formed by applying or printing on a PET substrate for drying and then drying. The method for preparing the solid electrolyte slurry is not particularly limited. Here, for the solid electrolyte layer green sheet, a binder having a small amount of residual carbide in the carbonization treatment is used.
The active material in the positive electrode layer green sheet and the negative electrode layer green sheet may be any material that can occlude and release lithium ions, and is not particularly limited. Of the positive electrode layer green sheet and the negative electrode layer green sheet, a layer containing an active material exhibiting a noble potential is used as the positive electrode layer green sheet, and a layer containing an active material exhibiting a lower potential is used as the negative electrode layer green sheet. Can be used.

As the active material for the positive electrode layer green sheets, for example, lithium nickel cobalt manganese oxide _{(LiNi x Co 1-y-} x Mn y O 2), lithium cobalt oxide (LiCoO _2), lithium nickel oxide (LiNiO _2), manganese Lithium phosphate (LiMn ₂ O ₄ ), lithium iron phosphate (LiFePO ₄ ), lithium cobalt phosphate (LiCoPO ₄ ), lithium manganese phosphate (LiMnPO ₄ ), lithium vanadium phosphate (Li ₃ V ₂ (PO ₄ ) ₃ ) And the like can be used.
Examples of the active material for the negative electrode layer green sheet include carbon materials such as hard carbon, soft carbon, and graphite, alloy materials such as Sn-based alloys and Si-based alloys, nitrides such as LiCoN, and lithium titanate (Li ₄ A lithium transition metal oxide such as Ti ₅ O ₁₂ ) or lithium vanadium phosphate (Li ₃ V ₂ (PO ₄ ) ₃ ) can be used. Moreover, you may use metal lithium foil.

The positive electrode layer green sheet and the negative electrode layer green sheet may contain a conductive additive. The conductive auxiliary agent is not particularly limited as long as it has conductivity. For example, a conductive carbon material, particularly carbon black, activated carbon, carbon carbon fiber, or the like can be used.
The content of the conductive assistant is preferably less than 90% by mass with respect to the mass of the active material. If it is 90% by mass or more, the amount of active material may be insufficient and the lithium storage capacity may be reduced.
The solid electrolyte used for each of the positive electrode layer green sheet, the negative electrode layer green sheet, and the solid electrolyte layer green sheet is not particularly limited as long as it has a low electron conductivity and a high lithium ion conductivity. Amorphous bodies (glass bodies), crystalline bodies, glass ceramics, and the like of the solid electrolytes and sulfide solid electrolytes can be used. In particular, an oxide-based solid electrolyte that can be fired at high temperature is preferable, and NASICON type oxides, perovskite type oxides, LISICON type oxides, garnet type oxides, oxide glasses, and the like can be used _{. 3} Al _0.3 Ti _1.7 (PO ₄ ) ₃ , Li _1.5 Al _0.5 Ge _1.5 (PO ₄ ) ₃ , Li _0.29 La _0.571 TiO ₃ , Li ₄ SiO ₄ -Li _{3 PO 4, Li 3 BO 3} -Li 3 PO 4, Li 7 La 3 Zr 2 O 12, Li 3.4 V 0.6 Si 0.4 O 4 and the like can be used.

The solid electrolyte used for each of the positive electrode layer green sheet, the negative electrode layer green sheet, and the solid electrolyte layer green sheet may be the same or different, and two or more solid electrolytes may be used in the same green sheet. Good.
The binder used for each of the positive electrode layer green sheet, the negative electrode layer green sheet, and the solid electrolyte layer green sheet needs to be decomposed under the firing conditions described below. For example, polyvinyl alcohol, polyvinyl butyral, polyvinyl acetal, polyvinylidene fluoride, polytetra Fluoroethylene, ethyl cellulose, acrylic resin, or the like can be used.

Furthermore, the binder used in the positive electrode layer green sheet and the negative electrode layer green sheet is preferably a binder having a large amount of residual carbide per unit mass, and the binder used in the solid electrolyte layer is a residual carbide per unit mass. A small amount of binder is desirable. The positive electrode layer green sheet and the negative electrode layer green sheet can be fired in an inert atmosphere to leave many carbides, and the solid electrolyte layer green sheet can be fired in an active atmosphere to reduce carbides.
The binder used for each of the positive electrode layer green sheet, the negative electrode layer green sheet, and the solid electrolyte layer green sheet is preferably 3% by mass or more and 40% by mass or less. If the binder is less than 3% by mass, sufficient binding cannot be achieved and bending resistance may be low. When the binder is larger than 40% by mass, the battery capacity per electrode volume may be greatly reduced. The binder is more preferably 3% by mass or more and 25% by mass or less.

Each of the positive electrode layer green sheet, the negative electrode layer green sheet, and the solid electrolyte layer green sheet may contain a firing aid that promotes formation of a matrix structure in each green sheet during firing and lowers the firing temperature. The firing aid is not particularly limited as long as it does not react with the active material and the solid electrolyte and has a softening point temperature lower than the firing temperature of the solid electrolyte. For example, a boron compound can be used. By adjusting the content and firing temperature of the firing aid of each green sheet, when forming a laminated fired body by firing, it prevents cracking due to internal strain and internal stress of each layer and promotes the formation of a matrix structure can do.

Each of the positive electrode layer green sheet, the negative electrode layer green sheet, and the solid electrolyte layer green sheet may contain a plasticizer to improve bending resistance, and the plasticizer is not particularly limited as long as it volatilizes below the firing temperature. For example, dioctyl phthalate, dibutyl phthalate, dioctyl adipate and the like can be used.
The solvent used for each of the positive electrode slurry, the negative electrode slurry, and the solid electrolyte slurry is not particularly limited as long as the binder can be dissolved. For example, alcohols such as ethanol, isopropanol, and n-butanol, toluene, ethyl acetate, butyl acetate, Use organic solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, ethylene glycol ethyl ether, isophorone, butyl lactate, dioctyl phthalate, dioctyl adipate, benzyl alcohol, N, N-dimethylformamide, N-methyl-2-pyrrolidone, and water be able to. In addition, these solvents may be used independently and may use 2 or more types together. The boiling point of the solvent is preferably 220 ° C. or lower because the slurry can be easily dried.

The positive electrode slurry, the negative electrode slurry, and the solid electrolyte slurry can be prepared by mixing the active material, the solid electrolyte, the binder, the conductive aid, the firing aid, the solvent, and the like described above. The method for mixing the slurry is not particularly limited, and additives such as thickeners, plasticizers, antifoaming agents, leveling agents, and adhesion imparting agents may be added as necessary.
Specifically, the application and printing methods of the positive electrode slurry, the negative electrode slurry, and the solid electrolyte slurry include a doctor blade method, a calendar method, a spin coating method, a dip coating method, an ink jet method, an offset method, a die coating method, a spray method, and a screen. A printing method or the like can be used.

The drying method of a positive electrode slurry, a negative electrode slurry, and a solid electrolyte slurry is not specifically limited, For example, heat drying, reduced pressure drying, heating reduced pressure drying, etc. can be used. The drying atmosphere is not particularly limited, and can be performed, for example, in an air atmosphere or an inert atmosphere (nitrogen or argon atmosphere).
The thickness of the positive electrode layer green sheet and the negative electrode layer green sheet can be selected according to the desired battery capacity.

The thickness of the solid electrolyte layer is preferably in the range of 1 μm to 500 μm. If it is thinner than 1 μm, the positive electrode layer and the negative electrode layer are short-circuited, and not only the performance of the all-solid-state secondary battery is lowered, but also the safety may be lowered. If it is thicker than 500 μm, the movement of conductive ions such as lithium ions in the solid electrolyte layer is hindered, and the output of the all-solid secondary battery may be lowered.
The material of the current collector foil is not particularly limited as long as it has conductivity. For example, a metal material such as stainless steel, nickel, aluminum, iron, titanium, copper, palladium, gold, and platinum can be used. . It is preferable to select in consideration of not melting and decomposing under the firing conditions described later, or taking into consideration the battery operating potential and conductivity applied to the current collector foil.

The all-solid-state secondary battery in one embodiment of the present invention is obtained by baking a battery constituent layer precursor containing a binder, such as a positive electrode layer green sheet, a solid electrolyte layer green sheet, and a negative electrode layer green sheet, and degreasing the binder. It is formed by stacking. For example, the all-solid-state secondary battery is formed by laminating a positive electrode layer, a solid electrolyte layer, and a negative electrode layer, which are each fired body, in this order and sandwiching them with a current collector foil, or laminating a positive electrode layer, a solid electrolyte layer, and a negative electrode layer in this order. It can be produced by forming a current collecting layer on the opposite side of the positive electrode layer and negative electrode solid electrolyte layer in the laminated structure and sandwiching the laminated structure between the current collecting layers. The firing conditions can be the same as the firing conditions in the formation of the laminated fired body.

In addition, an all-solid secondary battery according to an embodiment of the present invention is a laminate of battery constituent layer precursors containing a binder, such as a laminate green including a positive electrode layer green sheet, a solid electrolyte layer green sheet, and a negative electrode layer green sheet. It is also formed by producing a sheet, firing, and degreasing the binder. The laminate green sheet may be sandwiched between current collector foils, or a current collector layer may be formed on the laminate green sheet and fired at once. The firing conditions can be the same as the firing conditions in the formation of the laminated fired body.

In addition, the all-solid-state secondary battery according to one embodiment of the present invention includes a laminate of battery constituent layer precursors containing a binder on a current collector foil, such as a positive electrode layer green sheet, a solid electrolyte layer green sheet, and a negative electrode layer green. It is also formed by producing a laminate green sheet with current collector foil on which a laminate green sheet containing a sheet is formed and firing, and degreasing the binder. In addition, the all-solid-state secondary battery is formed by bonding the current collector foil on the positive electrode layer green sheet or the negative electrode layer green sheet farthest from the current collector foil of the laminate green sheet with current collector foil, or forming a current collector layer. It can also be produced by batch firing. The firing conditions can be the same as the firing conditions in the formation of the laminated fired body.

Furthermore, the all solid state secondary battery in one embodiment of the present invention can be formed as a series all solid state secondary battery. For example, a battery constituent layer precursor containing a binder, for example, a positive electrode layer green sheet, a solid electrolyte layer green sheet, and a negative electrode layer green sheet are fired, and each fired body obtained by degreasing the binder is a positive electrode layer, a solid The electrolyte layer and the negative electrode layer are formed by sandwiching the current collector foil and continuously laminating. Or it can form by forming a current collection layer on each of the positive electrode layer and negative electrode layer which are not in contact with the solid electrolyte layer, and laminating them continuously. The firing conditions can be the same as the firing conditions in the formation of the laminated fired body.

Moreover, the all solid state secondary battery as the series all solid state secondary battery in one embodiment of the present invention is obtained by firing a continuous laminate green sheet obtained by continuously laminating a laminate green sheet via a current collector foil, It is also formed by degreasing. In addition, the all-solid-state secondary battery is formed by forming a current collecting layer on each of the positive electrode layer and the negative electrode layer that are not in contact with the solid electrolyte layer of the laminated green sheet, and firing the continuously laminated green sheet continuously laminated, It is also formed by degreasing the binder. The firing conditions can be the same as the firing conditions in the formation of the laminated fired body.

Moreover, the all-solid-state secondary battery as the series all-solid-state secondary battery in one embodiment of the present invention is a continuous laminate green sheet obtained by continuously laminating a laminate green sheet with current collector foil, and fired. It is also formed by degreasing the binder. Also produced by laminating the current collector foil on the cathode layer green sheet or the anode layer green sheet farthest from the current collector foil of the continuous laminate green sheet with the current collector foil or by forming the current collector layer and firing at once. can do. The firing conditions can be the same as the firing conditions in the formation of the laminated fired body.
The heating temperature in the firing step is equal to or higher than the thermal decomposition temperature of the binder contained in the battery constituent layer precursor, and is lower than the oxidation temperature of the electrode active material or the combustion temperature of the current collector foil, specifically 300 degreeC or more and 1100 degrees C or less are preferable, and also 300 degreeC or more and 900 degrees C or less are preferable.

When the heating temperature is lower than 300 ° C., the binder does not completely burn and remains as a residue, which may hinder electronic conduction and ionic conduction. If the heating temperature is higher than 1100 ° C., the solid electrolyte may be melted and altered, thereby inhibiting ionic conduction. The atmosphere in the firing step is not particularly limited. For example, the atmosphere can be performed in an air atmosphere or in an inert atmosphere (nitrogen or argon atmosphere), but the reaction between the active material and the current collector foil or the current conductivity of the current collector foil can be performed. When there is a concern about the decrease, it is desirable to carry out in an inert atmosphere. The time for the firing step is not particularly limited as long as the binder used is sufficiently decomposed.
The continuous laminate green sheet used for the series all solid state secondary battery is a current collector foil of one laminate green sheet and a positive electrode layer green sheet or negative electrode of the other laminate green sheet among a plurality of laminate green sheets. The green sheets are laminated so as to be adjacent to each other. The method for laminating the laminate green sheet is not particularly limited, and for example, a flat plate press, a roll press, a hot press, a cold isostatic press, a hot isostatic press, or the like can be used.

As described above, the all-solid-state secondary battery according to one embodiment of the present invention is the all-solid-state secondary battery including the positive electrode layer, the solid electrolyte layer, and the negative electrode layer. The amount of carbide per unit mass contained in the positive electrode layer, the solid electrolyte The amount of carbide per unit mass contained in the layer and the amount of carbide per unit mass contained in the negative electrode layer satisfy the relationship of positive electrode layer> solid electrolyte layer and negative electrode layer> solid electrolyte layer. Therefore, by maintaining the electron transfer resistance of the solid electrolyte layer high and the electron transfer resistance of the positive electrode layer and the negative electrode layer low, the interface between the metal current collector foil and the positive electrode layer and between the metal current collector foil and the negative electrode layer. An all-solid secondary battery with low resistance can be realized.
Specifically, for example, by making the carbonization rate of the resin contained in each of the positive electrode layer precursor and the negative electrode layer precursor larger than the carbonization rate of the resin contained in the solid electrolyte layer precursor, all of the large capacity can be exhibited. A solid secondary battery can be realized.

In addition, for example, the amount of residual carbide after firing of the positive electrode layer precursor, the amount of residual carbide per unit mass after firing of the precursor of the solid electrolyte layer, and the unit after firing of the negative electrode layer precursor The kind and content of the binder made of an organic resin are set so that the amount of baked residual carbide per mass satisfies the relationship of positive electrode layer> solid electrolyte layer and negative electrode layer> solid electrolyte layer. Thereby, the amount of carbide per unit mass contained in the positive electrode layer, the amount of carbide per unit mass contained in the solid electrolyte layer, and the amount of carbide per unit mass contained in the negative electrode layer are positive electrode layer> solid electrolyte layer, and An all-solid secondary battery that satisfies the relationship of negative electrode layer> solid electrolyte layer can be easily formed. Further, for example, the carbonization rate of the binder that is a resin contained in the precursor of the positive electrode layer, the carbonization rate of the binder that is the resin contained in the precursor of the solid electrolyte layer, and the carbonization of the binder that is the resin contained in the precursor of the negative electrode layer. The binder is selected so that the ratio satisfies the relationship of positive electrode layer> solid electrolyte layer and negative electrode layer> solid electrolyte layer. Thus, for example, the binder content can be reduced by selecting a binder with a high carbonization rate, and conversely, when a binder with a low stretch rate is used, by increasing the binder content, The amount of carbide per unit mass contained in each layer of the solid secondary battery can be easily adjusted.

The amount of carbide per unit mass contained in the positive electrode layer is larger than the amount of carbide per unit mass contained in the solid electrolyte layer, and the amount of carbide per unit mass contained in the negative electrode layer is contained in the solid electrolyte layer. Since it can be realized by selecting a binder so that it exceeds the amount of carbide per unit mass, the capacity of all-solid-state secondary batteries can be increased without increasing the manufacturing process or increasing costs. Can do.

Hereinafter, an all-solid-state secondary battery according to an embodiment of the present invention will be described with specific examples and comparative examples. In addition, this invention is not restrict | limited by the following Example.
In the following description, pellets before firing and green sheets before firing are referred to as pellet precursors and green sheet precursors, and pellets after firing and green sheets after firing are referred to as pellet fired bodies and green sheet fired bodies. That's it.

Example 1
<Preparation of positive electrode layer pellet precursor>
Lithium cobaltate LiCoO ₂ (hereinafter referred to as LCO) powder 50 parts by mass as a positive electrode active material, Li _1.5 Al _0.5 Ge _1.5 (PO ₄ ) ₃ (hereinafter referred to as LAGP) powder as an inorganic solid electrolyte 50 parts by mass and 16 parts by mass of ethyl cellulose (manufactured by Wako Pure Chemical Industries) as a binder were mixed using a mortar. The mixture thus obtained was pressed at 1000 kgf / cm ² using a hot press machine and formed into a cylindrical positive electrode layer pellet precursor having a diameter of 10 mm and a thickness of 1.1 mm.

<Preparation of solid electrolyte layer pellet precursor>
As an inorganic solid electrolyte, 100 parts by mass of LAGP powder and 16 parts by mass of polyvinyl butyral (manufactured by Kuraray) as a binder were mixed using a mortar. The mixture thus obtained was pressed at 1000 kgf / cm ² using a hot press machine and formed into a cylindrical solid electrolyte layer pellet precursor having a diameter of 10 mm and a thickness of 1.1 mm.
<Preparation of negative electrode layer pellet precursor>
Lithium titanate Li ₄ Ti ₅ O ₁₂ (hereinafter referred to as LTO) powder as a negative electrode active material, 50 parts by mass of LAGP powder as an inorganic solid electrolyte, and 16 parts by mass of ethyl cellulose as a binder were mixed using a mortar. The mixture thus obtained was pressed at 1000 kgf / cm ² using a hot press machine and formed into a cylindrical negative electrode layer pellet precursor having a diameter of 10 mm and a thickness of 1.1 mm.

<Degreasing and firing process>
The positive electrode layer pellet precursor, the solid electrolyte layer pellet precursor, and the negative electrode layer pellet precursor are each heated from room temperature to 500 ° C. at a temperature increase rate of 20 ° C./min in a nitrogen stream and held at 500 ° C. for 30 minutes. Then, degreasing was performed. After degreasing, the temperature was increased from 500 ° C. to 800 ° C. at a temperature increase rate of 20 ° C./min, held at 800 ° C. for 30 minutes, and then cooled to room temperature in a furnace, and positive electrode layer pellets, solid electrolyte layer pellets, And the sintered body of each negative electrode layer pellet was obtained.

<Production process of all-solid-state secondary battery>
The all-solid-state secondary battery shown in FIG. 1 was produced using the positive electrode layer pellet fired body, solid electrolyte layer pellet fired body, and negative electrode layer pellet fired body obtained as described above. Specifically, a laminate in which the positive electrode layer pellet fired body 13, the solid electrolyte layer pellet fired body 12 and the negative electrode layer pellet fired body 11 were laminated in this order was prepared. The laminate was sandwiched between two stainless steel foils as the unfired metal current collector foil 14 and pressed. That is, two stainless steel foils as unfired metal current collector foils 14 are laminated on the surface opposite to the solid electrolyte layer pellet fired body 12 in the negative electrode layer pellet fired body 11 and the positive electrode layer pellet fired body 13. The all-solid-state secondary battery was produced by pressure bonding at 1000 kgf / cm ² using a hot press machine.

(Example 2)
<Slurry production process>
<Preparation of slurry for positive electrode layer green sheet>
50 parts by mass of LCO powder as a positive electrode active material, 50 parts by mass of LAGP powder as an inorganic solid electrolyte, 16 parts by mass of ethyl cellulose (manufactured by Wako Pure Chemical Industries) as a binder, 4.8 parts by mass of dibutyl phthalate (DBP) as a plasticizer, solvent 22 parts by mass of terpineol was mixed to make a slurry, and this slurry was defoamed to prepare a positive electrode layer green sheet slurry.

<Preparation of slurry for inorganic solid electrolyte layer green sheet>
100 parts by mass of LAGP powder as an inorganic solid electrolyte, 16 parts by mass of polyvinyl butyral as a binder, 4.8 parts by mass of DBP as a plasticizer, and 22 parts by mass of solvent terpineol are mixed to form a slurry, and the slurry is defoamed to produce an inorganic solid electrolyte A layer green sheet slurry was prepared.
<Preparation of slurry for negative electrode layer green sheet>
50 parts by mass of LTO powder as the negative electrode active material, 50 parts by mass of LAGP powder as the inorganic solid electrolyte, 16 parts by mass of ethyl cellulose (manufactured by Wako Pure Chemical Industries) as the binder, 4.8 parts by mass of DBP as the plasticizer, and 22 parts by mass of solvent terpineol The slurry was defoamed to prepare a slurry for the negative electrode layer green sheet.

<Green sheet precursor production process>
On the release PET film, the positive electrode layer green sheet slurry, the inorganic solid electrolyte layer green sheet slurry, and the negative electrode layer green sheet slurry prepared as described above were respectively applied and dried, and then the release PET film. Were peeled off to prepare a positive electrode layer green sheet precursor, an inorganic solid electrolyte layer green sheet precursor, and a negative electrode layer green sheet precursor.
<Degreasing and firing process>
The positive electrode layer green sheet precursor, inorganic solid electrolyte layer green sheet precursor, and negative electrode layer green sheet precursor produced as described above were each fired by the method described in Example 1, and the positive electrode layer fired body, inorganic A solid electrolyte layer fired body and a negative electrode layer fired body were obtained.

<Production process of all-solid-state secondary battery>
Using the positive electrode layer fired body, solid electrolyte layer fired body, and negative electrode layer fired body obtained as described above, an all-solid secondary battery shown in FIG. 2 was produced. Specifically, a laminate in which the positive electrode layer fired body 23, the solid electrolyte layer fired body 22 and the negative electrode layer fired body 21 were laminated in this order was prepared. The laminate was sandwiched between two stainless steel foils as the unfired metal current collector foil 14 and pressed. That is, two stainless steel foils as the unfired metal current collector foil 14 are laminated on the surface of the positive electrode layer fired body 23 and the negative electrode layer fired body 21 opposite to the solid electrolyte layer fired body 22, respectively, Was used for pressure bonding at 1000 kgf / cm ² to produce an all-solid-state secondary battery.

(Example 3)
<Slurry production process>
In the slurry preparation step, the same operation as in Example 2 was performed. Thereby, the slurry for positive electrode layer green sheets, the slurry for inorganic solid electrolyte layer green sheets, and the slurry for negative electrode layer green sheets were produced.
<Process for producing laminated green sheet precursor>
The positive electrode layer green sheet slurry, the inorganic solid electrolyte layer green sheet slurry, and the negative electrode layer green sheet slurry are each applied onto the release PET film, dried, and then released from the release PET film. A green sheet precursor, an inorganic solid electrolyte layer green sheet precursor, and a negative electrode layer green sheet precursor were prepared. The produced positive electrode layer green sheet precursor, inorganic solid electrolyte layer green sheet precursor, and negative electrode layer green sheet precursor are laminated in this order, and are pressure-bonded at 1000 kgf / cm ² using a hot press, and the laminate green sheet precursor is laminated. The body was made.

<Degreasing and firing process>
The produced laminated green sheet precursor was fired by the method described in Example 1 to obtain a laminated fired body in which the positive electrode layer, the inorganic solid electrolyte layer, and the negative electrode layer were laminated.
<Production process of all-solid-state secondary battery>
The all-solid-state secondary battery shown in FIG. 3 was produced using the laminated fired body obtained as described above. Specifically, a laminated fired body 24 in which a positive electrode layer fired body 23, a solid electrolyte layer fired body 22 and a negative electrode layer fired body 21 are laminated in this order was prepared. Then, the laminated fired body 24 was sandwiched between two stainless steel foils as the unfired metal current collector foil 14 and pressed. That is, two stainless steel foils as unfired metal current collector foils 14 are laminated on the surface opposite to the solid electrolyte layer fired body 22 in the positive electrode layer fired body 23 and the negative electrode layer fired body 21, respectively. Was used for pressure bonding at 1000 kgf / cm ² to produce an all-solid-state secondary battery.

(Example 4)
<Slurry production process>
In the slurry preparation step, the same operation as in Example 2 was performed. This produced the positive electrode slurry, the inorganic solid electrolyte slurry, and the negative electrode slurry.
<Process for producing laminated green sheet precursor with current collector foil>
As the positive electrode current collector foil, a stainless steel foil having a thickness of 20 μm was used, and the prepared positive electrode slurry was applied onto the stainless steel foil and dried to form a positive electrode layer green sheet. On this positive electrode layer green sheet, an inorganic solid electrolyte slurry was applied and then dried to form an inorganic solid electrolyte layer green sheet. Finally, the negative electrode slurry is applied onto the inorganic solid electrolyte layer green sheet and dried to form a negative electrode layer green sheet. Further, the negative electrode current collector foil is bonded onto the negative electrode layer green sheet, and 1000 kgf using a hot press machine. / Cm ² was pressed to produce a laminate green sheet precursor with current collector foil.

<Degreasing and firing process, production process of all-solid secondary battery>
The all-solid-state secondary battery shown in FIG. 4 was produced using the laminated green sheet precursor with current collector foil produced as described above. Specifically, the laminate green sheet precursor with current collector foil is fired by the method described in Example 1, and the positive electrode layer fired body 23, the solid electrolyte layer fired body 22, and the negative electrode layer fired body 21 are laminated in this order. A laminated fired body 24 was prepared. The laminated fired body 24 was sandwiched between two fired bodies of stainless steel foil as the fired metal current collector foil 25. That is, in the positive electrode layer fired body 23 and the negative electrode layer fired body 21, a fired body of a stainless steel foil as the fired metal current collector foil 25 is laminated on the surface opposite to the solid electrolyte layer fired body 22, respectively. A battery was produced.

(Example 5)
<Slurry production process>
In the slurry preparation step, the same operation as in Example 2 was performed. This produced the positive electrode slurry, the inorganic solid electrolyte slurry, and the negative electrode slurry.
<Preparation process of continuous laminate green sheet precursor with current collector foil>
As the positive electrode current collector foil, a stainless steel foil having a thickness of 20 μm was used, and the prepared positive electrode slurry was applied onto the stainless steel foil and dried to form a positive electrode layer green sheet. On this positive electrode layer green sheet, an inorganic solid electrolyte slurry was applied and dried to form an inorganic solid electrolyte layer green sheet. Finally, a negative electrode slurry was applied on the inorganic solid electrolyte layer green sheet and dried to form a negative electrode layer green sheet. This produced the laminated body green sheet with current collection foil.
A plurality of (5 in the case of FIG. 5) laminate green sheets with current collector foil thus produced were laminated to produce a continuous laminate green sheet. A stainless steel foil having a thickness of 20 μm is placed on the continuous laminate green sheet to form a negative electrode current collector foil, which is pressure-bonded at 1000 kgf / cm ² using a hot press, and a continuous laminate green sheet precursor with a current collector foil is obtained. Produced.

<Degreasing / firing process, production process of serial all solid state secondary battery>
A serial all-solid secondary battery shown in FIG. 5 was produced using the continuous laminate green sheet precursor with current collector foil produced as described above. Specifically, the produced continuous laminated green sheet precursor with current collector foil was fired by the method described in Example 1, and the positive electrode layer fired body 23, the solid electrolyte layer fired body 22, and the negative electrode layer fired body 21 were A plurality of laminated fired bodies 24 that were sequentially laminated were prepared. The plurality of laminated fired bodies 24 are laminated in series (five in the case of FIG. 5) through a fired body of stainless steel foil as a fired metal current collector foil 25, and the positive electrode current collector foil and the negative electrode are formed at both ends. A series all-solid secondary battery was produced by sandwiching between stainless steel metal current collector foils 25 as current collector foils.

(Example 6)
Example except that ethyl cellulose (manufactured by Wako Pure Chemical Industries) was used as a binder for the positive electrode layer pellet precursor and negative electrode layer pellet precursor, and an acrylic polymer (manufactured by Soken Chemical) was used as the binder for the solid electrolyte layer pellet precursor. The all-solid-state secondary battery was produced by the same method as 1.
(Example 7)
Except for using ethyl cellulose (manufactured by Wako Pure Chemical) as a binder for the positive electrode layer green sheet precursor and negative electrode layer green sheet precursor, and using an acrylic polymer (manufactured by Soken Chemical) as the binder for the solid electrolyte layer green sheet precursor. An all-solid secondary battery was produced in the same manner as in Example 2.

(Example 8)
Except for using ethyl cellulose (manufactured by Wako Pure Chemical) as a binder for the positive electrode layer green sheet precursor and negative electrode layer green sheet precursor, and using an acrylic polymer (manufactured by Soken Chemical) as the binder for the solid electrolyte layer green sheet precursor. An all-solid secondary battery was produced in the same manner as in Example 3.
Example 9
Except for using ethyl cellulose (manufactured by Wako Pure Chemical) as a binder for the positive electrode layer green sheet precursor and negative electrode layer green sheet precursor, and using an acrylic polymer (manufactured by Soken Chemical) as the binder for the solid electrolyte layer green sheet precursor. An all-solid secondary battery was produced in the same manner as in Example 4.
(Example 10)
Except for using ethyl cellulose (manufactured by Wako Pure Chemical) as a binder for the positive electrode layer green sheet precursor and negative electrode layer green sheet precursor, and using an acrylic polymer (manufactured by Soken Chemical) as the binder for the solid electrolyte layer green sheet precursor. A series all-solid secondary battery was produced in the same manner as in Example 5.

(Comparative Example 1)
An all-solid-state secondary battery is produced in the same manner as in Example 1 except that ethyl cellulose (manufactured by Wako Pure Chemical Industries) is used as a binder for the positive electrode layer pellet precursor, the solid electrolyte layer pellet precursor, and the negative electrode layer pellet precursor. did.
(Comparative Example 2)
In the same manner as in Example 2, except that ethyl cellulose (manufactured by Wako Pure Chemical Industries) was used as a binder for the positive electrode layer green sheet precursor, solid electrolyte layer green sheet precursor, and negative electrode layer green sheet precursor, A secondary battery was produced.

(Comparative Example 3)
In the same manner as in Example 3, except that ethyl cellulose (manufactured by Wako Pure Chemical Industries, Ltd.) was used as a binder for the positive electrode layer green sheet precursor, the solid electrolyte layer green sheet precursor, and the negative electrode layer green sheet precursor, A secondary battery was produced.
(Comparative Example 4)
In the same manner as in Example 4, except that ethyl cellulose (manufactured by Wako Pure Chemical Industries, Ltd.) was used as a binder for the positive electrode layer green sheet precursor, the solid electrolyte layer green sheet precursor, and the negative electrode layer green sheet precursor, A secondary battery was produced.

(Comparative Example 5)
In the same manner as in Example 5, except that ethyl cellulose (manufactured by Wako Pure Chemical Industries, Ltd.) was used as a binder for the positive electrode layer green sheet precursor, the solid electrolyte layer green sheet precursor, and the negative electrode layer green sheet precursor, a series all solids A secondary battery was produced.
(Comparative Example 6)
An all-solid-state secondary battery was produced in the same manner as in Example 1 except that polyvinyl butyral (manufactured by Kuraray) was used as a binder for the positive electrode layer pellet precursor, the solid electrolyte layer pellet precursor, and the negative electrode layer pellet precursor. .

(Comparative Example 7)
The all-solid secondary in the same manner as in Example 2 except that polyvinyl butyral (manufactured by Kuraray) was used as a binder for the positive electrode layer green sheet precursor, the solid electrolyte layer green sheet precursor and the negative electrode layer green sheet precursor. A battery was produced.
(Comparative Example 8)
The all-solid secondary in the same manner as in Example 3 except that polyvinyl butyral (manufactured by Kuraray) was used as a binder for the positive electrode layer green sheet precursor, solid electrolyte layer green sheet precursor, and negative electrode layer green sheet precursor. A battery was produced.

(Comparative Example 9)
The all-solid secondary in the same manner as in Example 4 except that polyvinyl butyral (manufactured by Kuraray) was used as a binder for the positive electrode layer green sheet precursor, solid electrolyte layer green sheet precursor, and negative electrode layer green sheet precursor. A battery was produced.
(Comparative Example 10)
In the same manner as in Example 5 except that polyvinyl butyral (manufactured by Kuraray) was used as a binder for the positive electrode layer green sheet precursor, the solid electrolyte layer green sheet precursor, and the negative electrode layer green sheet precursor, the series all solids A secondary battery was produced.

Next, the battery characteristics of the all-solid secondary batteries and the series all-solid secondary batteries in Examples and Comparative Examples produced in this manner were evaluated.
<Measurement of carbonization rate>
First, the carbonization rate was measured for each type of binder used in each example and comparative example. That is, the carbonization rate was measured for three types of polyvinyl butyral, acrylic polymer, and ethyl cellulose. Specifically, 1 g of a binder was placed on a firing boat, fired at 800 ° C. for 30 minutes under a nitrogen flow, mass measurement was performed again, and the carbonization rate was calculated by the following formula. The calculation results are shown in Table 1.
Carbonization rate (%) = Amount of carbonized material after firing / Binder mass before firing (1 g) × 100

<Measurement of carbide content>
The amount of carbide was measured using solid electrolyte layer pellets using various binders used in each example and comparative example. Specifically, the mass of the solid electrolyte layer pellet produced by the method shown in Example 1 was measured, and the mass A was obtained. Thereafter, the mass was measured again by baking at 800 ° C. for 30 minutes in the air atmosphere, and the mass B was obtained. And the amount of carbides (the amount of residual carbides) was computed with the following formulas. Table 2 shows the calculation results. The solid electrolyte layer pellet mass was 1 g.
Carbide content (mg) = Mass A-Mass B

<Battery characteristics evaluation>
The battery characteristics were evaluated by the following method.
Five all-solid-state secondary batteries and series all-solid-state secondary batteries shown in each example and comparative example were produced, and battery characteristics were evaluated. Specifically, the battery was charged to 2.7 V by a constant current method of 0.1 C, and then discharged to 1.5 V at 0.1 C, and the discharge amount was defined as a discharge capacity A. The discharge capacity A was an average value of five batteries. Then, it charged to 2.7V at 0.1C, discharged to 1.5V at 1C, and the discharge capacity B was calculated | required. The discharge capacity B was also an average value of five secondary batteries. Both discharge capacities A and B are discharge capacities per positive electrode active material. And the discharge capacity maintenance factor represented by ratio (discharge capacity B / discharge capacity Ax100 (%)) of the discharge capacity of discharge capacity B and discharge capacity A was calculated | required. Table 3 shows the calculation results. A higher discharge capacity retention rate means an all-solid-state secondary battery having excellent output characteristics as a battery and a low internal resistance.

<Evaluation results>
As shown in Table 1, the carbonization rate of polyvinyl butyral and acrylic polymer was found to be significantly lower than that of ethylcellulose. As shown in Table 2, similarly to the carbonization rate measurement results, the amount of residual carbides of polyvinyl butyral and acrylic polymer in the solid electrolyte layer was significantly lower than the amount of residual carbides of ethyl cellulose.
In addition, as shown in Table 3, the all-solid secondary batteries shown in Examples 1 to 4 using ethyl cellulose as a binder for the positive electrode layer precursor and the negative electrode layer precursor and polyvinyl butyral as the binder for the solid electrolyte layer precursor were discharged. The capacity A was 100 mAh / g or more, and the discharge capacity retention rate was 45% or more. The all-solid secondary batteries shown in Examples 6 to 9 using ethyl cellulose as a binder for the positive electrode layer precursor and the negative electrode layer precursor and an acrylic polymer as the binder for the solid electrolyte layer precursor also had a discharge capacity A of 100 mAh / g. As described above, the discharge capacity retention rate was 45% or more.

On the other hand, the discharge capacity A of the all solid secondary batteries shown in Comparative Examples 1 to 4 in which ethyl cellulose was used as a binder for the precursor of all layers of the positive electrode layer, the solid electrolyte layer, and the negative electrode layer was less than 100 mAh / g.
In addition, the all-solid secondary batteries shown in Comparative Examples 6 to 9 using polyvinyl butyral as a binder for the precursors of all layers of the positive electrode layer, the solid electrolyte layer, and the negative electrode layer had a discharge capacity A of 100 mAh / g or more. However, the discharge capacity B was low and was lower than the discharge capacity retention ratios of Examples 1 to 4 and 6 to 9.

Further, the series all-solid secondary battery also showed the same tendency as the single-layer all-solid secondary battery, and the discharge capacity A was much higher than that of Comparative Example 5 in Examples 5 and 10 and Comparative Example 10. Moreover, the discharge capacity B of Examples 5 and 10 exceeded that of Comparative Examples 5 and 10.
From the above, it was confirmed that by using polyvinyl butyral or acrylic polymer having a low carbonization rate as the binder of the solid electrolyte layer precursor, the micro short-circuit between the positive electrode layer and the negative electrode layer is suppressed and a high discharge capacity A is exhibited. It was. Further, by using ethyl cellulose having a high carbonization rate as a binder for the precursor of the positive electrode layer and the negative electrode layer, the electron conductivity of the positive electrode layer and the negative electrode layer is improved, and a high discharge capacity B and a high discharge capacity maintenance rate are achieved. It was confirmed to show.

As described above, the entire contents of Japanese Patent Application No. 2016-032359 (filed on February 23, 2016), to which the present application claims priority, form part of the present disclosure by reference.
Further, although the present invention has been described by each embodiment, the scope of the present invention is not limited to the illustrated and described exemplary embodiments, and the same effects as those intended by the present invention are brought about. All embodiments are also included. Furthermore, the scope of the invention is not limited to the combinations of features of the invention defined by the claims, but can be defined by any desired combination of specific features among all the disclosed features.

11 Negative electrode layer pellet fired body 12 Solid electrolyte layer pellet fired body 13 Positive electrode layer pellet fired body 14 Unfired metal current collector foil 21 Negative electrode layer fired body 22 Solid electrolyte layer fired body 23 Positive electrode layer fired body 24 Laminated fired body 25 Fired metal collection Electric foil

Claims (12)

1. In the all-solid-state secondary battery including the positive electrode layer, the solid electrolyte layer, and the negative electrode layer,
   The amount of carbide per unit mass contained in the positive electrode layer, the amount of carbide per unit mass contained in the solid electrolyte layer, and the amount of carbide per unit mass contained in the negative electrode layer are: positive electrode layer> solid electrolyte layer, And the all-solid-state secondary battery satisfy | fills the relationship of the said negative electrode layer> the said solid electrolyte layer.
2. A method for producing an all-solid-state secondary battery including a positive electrode layer, a solid electrolyte layer, and a negative electrode layer,
   Firing the precursor of the positive electrode layer, the solid electrolyte layer and the negative electrode layer,
   The precursors of the positive electrode layer, the solid electrolyte layer, and the negative electrode layer each contain a resin that is carbonized by firing.
   Firing residual carbide amount per unit mass after firing of the positive electrode layer precursor, firing residual carbide amount per unit mass after firing of the solid electrolyte layer precursor, and unit after firing of the negative electrode layer precursor The type and content of the resin are set so that the amount of calcination residual carbide per mass satisfies the relationship of the positive electrode layer> the solid electrolyte layer and the negative electrode layer> the solid electrolyte layer. Manufacturing method of all-solid-state secondary battery.
3. The carbonization rate of the resin contained in the precursor of the positive electrode layer, the carbonization rate of the resin contained in the precursor of the solid electrolyte layer, and the carbonization rate of the resin contained in the precursor of the negative electrode layer are determined as follows. 3. The method for producing an all-solid-state secondary battery according to claim 2, wherein the relationship of the electrolyte layer and the negative electrode layer> the solid electrolyte layer is satisfied.
4. As each precursor of the positive electrode layer, the solid electrolyte layer and the negative electrode layer,
   The method for producing an all-solid-state secondary battery according to claim 2, wherein a positive electrode layer green sheet, a solid electrolyte layer green sheet, and a negative electrode layer green sheet are used.
5. As a precursor of the positive electrode layer, the solid electrolyte layer, and the negative electrode layer,
   4. The method for producing an all-solid-state secondary battery according to claim 2, wherein a laminate green sheet in which a positive electrode layer green sheet, a solid electrolyte layer green sheet, and a negative electrode layer green sheet are laminated in this order is used.
6. As a precursor of the positive electrode layer, the solid electrolyte layer, and the negative electrode layer,
   The laminate green sheet with current collector foil, in which a positive electrode layer green sheet, a solid electrolyte layer green sheet, and a negative electrode layer green sheet are laminated in this order on the current collector foil, is used. Manufacturing method for all-solid-state secondary battery.
7. As a precursor of the positive electrode layer, the solid electrolyte layer, and the negative electrode layer,
   The manufacturing method of the all-solid-state secondary battery of Claim 6 using the continuous laminated body green sheet formed by laminating | stacking two or more said laminated green sheets with a current collector foil.
8. A laminate green sheet for an all-solid secondary battery in which a positive electrode layer green sheet, a solid electrolyte layer green sheet, and a negative electrode layer green sheet are laminated in this order,
   The positive electrode layer green sheet, the solid electrolyte layer green sheet, and the negative electrode layer green sheet each contain a resin that is carbonized by firing,
   Calcination residual carbide amount per unit mass after firing of the positive electrode layer green sheet, calcination residual carbide amount per unit mass after firing of the solid electrolyte layer green sheet and per unit mass after firing of the negative electrode layer green sheet The type and content of the resin are set so that the amount of residual carbide in firing satisfies the relationship of the positive electrode layer green sheet> the solid electrolyte layer green sheet and the negative electrode layer green sheet> the solid electrolyte layer green sheet. A laminated green sheet for an all-solid-state secondary battery.
9. The carbonization rate of the resin contained in the positive electrode layer green sheet, the carbonization rate of the resin contained in the solid electrolyte layer green sheet, and the carbonization rate of the resin contained in the negative electrode layer green sheet are determined as follows: the positive electrode layer green sheet> the solid electrolyte The multilayer green sheet for an all-solid-state secondary battery according to claim 8, wherein a relationship of layer green sheet and negative electrode layer green sheet> solid electrolyte layer green sheet is satisfied.
10. A green sheet with a current collector foil for an all-solid-state secondary battery in which a positive electrode layer green sheet, a solid electrolyte layer green sheet and a negative electrode layer green sheet are laminated in this order on a current collector foil,
    The positive electrode layer green sheet, the solid electrolyte layer green sheet, and the negative electrode layer green sheet each contain a resin that is carbonized by firing,
    Calcination residual carbide amount per unit mass after firing of the positive electrode layer green sheet, calcination residual carbide amount per unit mass after firing of the solid electrolyte layer green sheet and per unit mass after firing of the negative electrode layer green sheet The type and content of the resin are set so that the amount of residual carbide in firing satisfies the relationship of the positive electrode layer green sheet> the solid electrolyte layer green sheet and the negative electrode layer green sheet> the solid electrolyte layer green sheet. A laminate green sheet with a current collector foil for an all-solid-state secondary battery.
11. The carbonization rate of the resin contained in the positive electrode layer green sheet, the carbonization rate of the resin contained in the solid electrolyte layer green sheet, and the carbonization rate of the resin contained in the negative electrode layer green sheet are determined as follows: the positive electrode layer green sheet> the solid electrolyte 11. The laminated green sheet with current collector foil for an all-solid-state secondary battery according to claim 10, wherein the relationship of layer green sheet and negative electrode layer green sheet> solid electrolyte layer green sheet is satisfied.
12. A continuous laminate green sheet for an all-solid-state secondary battery, comprising a plurality of laminate green sheets with current collector foils according to claim 10 or 11.

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