JP2021176134A - All-solid battery - Google Patents

Abstract

To provide an all-solid battery arranged so that a metal foil and a current collector in a metal-foil laminate film hardly short circuit.SOLUTION: An all-solid battery comprises a housing, a battery element, a current collector, and an insulator layer. The housing contains the battery element, the current collector and the insulator layer. The housing includes a metal foil laminate film. The battery element includes a positive electrode layer, a solid electrolyte layer and a negative electrode layer. The solid electrolyte layer serves to separate the positive electrode layer and the negative electrode layer. The current collector is in contact with an external surface of the battery element. The insulator layer is disposed between the housing and the current collector. The insulator layer contains an insulative material. The insulative material has a Young's modulus of 10 GPa or larger.SELECTED DRAWING: Figure 2

Description

The present disclosure relates to an all-solid-state battery.

Japanese Unexamined Patent Publication No. 2013-21904 (Patent Document 1) discloses a packaging material for an electrochemical cell, which includes a resin film and a metal foil.

Japanese Unexamined Patent Publication No. 2013-21904

The metal foil laminated film is formed by laminating resin films on both sides of the metal foil. The so-called "laminated battery" includes a metal foil laminated film as a housing. The housing houses the battery elements. Battery elements include electrode active materials and electrolytes.

The battery elements of an all-solid-state battery consist only of solids. The battery element of a liquid battery contains a liquid. The battery element of an all-solid-state battery may have a lower porosity than the battery element of a liquid-based battery. Therefore, the battery element of the all-solid-state battery tends to be harder than the battery element of the liquid-based battery. Hereinafter, the all-solid-state battery may be abbreviated as "battery".

FIG. 1 is a first schematic cross-sectional view for explaining foreign matter contamination.
The current collector 60 is arranged on the outer surface of the battery element 50. The current collector 60 can be, for example, a metal foil or the like.

For example, in the process of manufacturing a battery, it is assumed that a conductive foreign substance 1 (for example, a metal piece or the like) enters between the metal foil laminated film (housing 90) and the current collector 60. The conductive foreign matter 1 can be generated, for example, when the battery element 50 is cut.

For example, in order to reduce the deformation of the battery, an external force (F) may be applied to the battery by the restraining member. If an external force (F) is applied to the battery with the conductive foreign matter 1 in the battery, the conductive foreign matter 1 may break through the surface layer (first resin film 91) of the metal foil laminated film. When the conductive foreign matter 1 penetrates the first resin film 91, the metal foil 93 in the metal foil laminated film and the current collector 60 may be short-circuited.

An object of the present disclosure is to provide an all-solid-state battery in which the metal foil in the metal foil laminate film and the current collector are unlikely to be short-circuited.

Hereinafter, the technical configuration and the action and effect of the present disclosure will be described. However, the mechanism of action of the present disclosure involves estimation. The correctness of the mechanism of action does not limit the scope of claims.

The all-solid-state battery includes a housing, a battery element, a current collector, and an insulating layer.
The housing houses the battery element, the current collector and the insulating layer.
The housing includes a metal foil laminated film.
The battery element includes a positive electrode layer, a solid electrolyte layer and a negative electrode layer.
The solid electrolyte layer separates the positive electrode layer and the negative electrode layer.
The current collector is in contact with the outer surface of the battery element.
The insulating layer is arranged between the housing and the current collector.
The insulating layer contains an insulating material.
The insulating material has a Young's modulus of 10 GPa or more.

FIG. 2 is a second schematic cross-sectional view for explaining foreign matter contamination.
The housing 90 includes a metal foil laminated film. The metal foil laminated film has a three-layer structure. That is, the housing 90 is formed by laminating the first resin film 91, the metal foil 93, and the second resin film 92.

In the present disclosure, a hard insulating layer 70 is arranged between the housing 90 and the current collector 60. When an external force (F) is applied to the battery, it is considered that the conductive foreign matter 1 is not pushed toward the insulating layer 70 side but is pushed toward the housing 90 side. It is considered that the insulating layer 70 is hard. Since it is difficult for the conductive foreign matter 1 to penetrate the insulating layer 70, it is considered that the metal foil 93 and the current collector 60 are unlikely to be short-circuited.

The insulating layer 70 contains an insulating material. The Young's modulus of the insulating material is an index of the hardness of the insulating layer 70. If the Young's modulus of the insulating material is less than 10 GPa, the hardness of the insulating layer 70 may be insufficient. If the hardness of the insulating layer 70 is insufficient, the desired insulation resistance may not be realized when an external force (F) is applied to the battery.

FIG. 1 is a first schematic cross-sectional view for explaining foreign matter contamination. FIG. 2 is a second schematic cross-sectional view for explaining foreign matter contamination. FIG. 3 is a schematic cross-sectional view of the all-solid-state battery of the present embodiment. FIG. 4 is a first schematic plan view for explaining the cutting position of the battery element. FIG. 5 is a second schematic plan view for explaining the cutting position of the battery element. FIG. 6 is a schematic plan view for explaining the attachment position of the positive electrode current collector.

Hereinafter, embodiments of the present disclosure (hereinafter, also referred to as “the present embodiment”) will be described. However, the following description does not limit the scope of claims.

In the present embodiment, for example, the description such as "0.1 parts by mass to 10 parts by mass" indicates a range including the boundary value unless otherwise specified. For example, "0.1 parts by mass to 10 parts by mass" indicates a range of "0.1 parts by mass or more and 10 parts by mass or less".

<All-solid-state battery>
FIG. 3 is a schematic cross-sectional view of the all-solid-state battery of the present embodiment.
The battery 100 is an all-solid-state battery. The battery 100 includes a housing 90, a battery element 50, a current collector 60, and an insulating layer 70.

《Case》
The housing 90 houses the battery element 50, the current collector 60, and the insulating layer 70. The housing 90 is hermetically sealed. The housing 90 includes a metal foil laminated film. The metal foil laminated film may have, for example, a three-layer structure. That is, the housing 90 includes the first resin film 91, the metal foil 93, and the second resin film 92 (FIG. 2).

The first resin film 91 forms the inner surface of the housing 90. The first resin film 91 is in close contact with the metal foil 93. The first resin film 91 may have a thickness of, for example, 5 μm to 500 μm. The first resin film 91 may have a thickness of, for example, 10 μm to 100 μm. The first resin film 91 may have, for example, heat welding properties. The first resin film 91 may contain, for example, polypropylene (PP), acid-modified PP, heat-modified PP, and the like. The first resin film 91 may have, for example, a multilayer structure. The first resin film 91 may include, for example, a PP layer and a heat-modified PP layer.

The metal foil 93 is sandwiched between the first resin film 91 and the second resin film 92. The metal foil 93 may have a thickness of, for example, 5 μm to 500 μm. The metal foil 93 may have a thickness of, for example, 10 μm to 100 μm. The metal foil 93 may have, for example, a gas barrier function. The metal foil 93 may include, for example, an aluminum (Al) foil or the like.

The second resin film 92 forms the outer surface of the housing 90. The second resin film 92 is in close contact with the metal foil 93. The second resin film 92 may have a thickness of, for example, 5 μm to 500 μm. The second resin film 92 may have a thickness of, for example, 10 μm to 100 μm. The second resin film 92 may have, for example, insulating properties, piercing resistance, and the like. The second resin film 92 may contain, for example, polyethylene terephthalate (PET), nylon, or the like.

《Battery element》
The battery element 50 includes a positive electrode layer 10, a solid electrolyte layer 30, and a negative electrode layer 20. The solid electrolyte layer 30 is, so to speak, a separator. The solid electrolyte layer 30 is separated from the positive electrode layer 10 and the negative electrode layer 20.

The battery element 50 is a laminated type. The battery element 50 is formed by laminating the positive electrode layer 10, the solid electrolyte layer 30, and the negative electrode layer 20. The battery element 50 may have an arbitrary laminated structure as long as it includes one or more positive electrode layers 10, a solid electrolyte layer 30, and a negative electrode layer 20.

For example, the battery element 50 may be formed by laminating the positive electrode layer 10, the solid electrolyte layer 30, and the negative electrode layer 20 in this order.

For example, the battery element 50 may be formed by laminating the positive electrode layer 10, the solid electrolyte layer 30, the negative electrode layer 20, the solid electrolyte layer 30, and the positive electrode layer 10 in this order.

For example, the battery element 50 may be formed by laminating the negative electrode layer 20, the solid electrolyte layer 30, the positive electrode layer 10, the solid electrolyte layer 30, and the negative electrode layer 20 in this order.

The battery 100 may include one battery element 50 alone. The battery 100 may include a plurality of battery elements 50. The plurality of battery elements 50 may be stacked in the z-axis direction of FIG. The battery 100 may include, for example, 2 to 200 battery elements 50. The battery 100 may include, for example, 10 to 100 battery elements 50. The plurality of battery elements 50 may form a series circuit, for example. The plurality of battery elements 50 may form, for example, a parallel circuit.

(Positive electrode layer)
The positive electrode layer 10 is in close contact with the solid electrolyte layer 30. The positive electrode layer 10 includes at least the positive electrode active material layer 12. The positive electrode layer 10 may be substantially composed of, for example, the positive electrode active material layer 12. The positive electrode layer 10 may include, for example, the positive electrode current collector 11 and the positive electrode active material layer 12. The positive electrode current collector 11 may have a thickness of, for example, 5 μm to 50 μm. The positive electrode current collector 11 may contain, for example, an Al foil or the like.

The positive electrode active material layer 12 may have a thickness of, for example, 10 μm to 200 μm. The positive electrode active material layer 12 contains at least the positive electrode active material. The positive electrode active material layer 12 may be substantially composed of, for example, a positive electrode active material. The positive electrode active material layer 12 may contain, for example, a solid electrolyte, a conductive material, a binder, and the like in addition to the positive electrode active material. Examples of the positive electrode active material include lithium cobalt oxide, lithium nickel oxide, lithium manganate, lithium nickel cobalt manganate and the like (for example, LiNi _1/3 Co _1/3 Mn _1/3 O _{2 and the} like), lithium cobalt aluminate, and the like. And at least one selected from the group consisting of lithium cobalt oxide may be included. The solid electrolyte may contain, for example, a sulfide solid electrolyte or the like [for example, LiBr-LiI- (Li _{2 SP 2} S ₅ ) or the like]. The conductive material may include, for example, a conductive carbon material or the like [for example, vapor-grown carbon fiber (VGCF) or the like]. The binder may contain, for example, polyvinylidene fluoride (PVdF) and the like.

(Solid electrolyte layer)
The solid electrolyte layer 30 is interposed between the positive electrode layer 10 and the negative electrode layer 20. The solid electrolyte layer 30 spatially separates the positive electrode layer 10 and the negative electrode layer 20. The solid electrolyte layer 30 blocks electron conduction between the positive electrode layer 10 and the negative electrode layer 20. The solid electrolyte layer 30 forms an ionic conduction path between the positive electrode layer 10 and the negative electrode layer 20. The solid electrolyte layer 30 may have a thickness of, for example, 1 μm to 100 μm.

The solid electrolyte layer 30 contains at least a solid electrolyte. The solid electrolyte layer 30 may be substantially composed of, for example, a solid electrolyte. The solid electrolyte layer 30 may contain, for example, a binder or the like in addition to the solid electrolyte. The solid electrolyte may contain, for example, a sulfide solid electrolyte or the like [for example, LiBr-LiI- (Li _{2 SP 2} S ₅ ) or the like]. The binder may contain, for example, butadiene rubber or the like.

(Negative electrode layer)
The negative electrode layer 20 is in close contact with the solid electrolyte layer 30. The negative electrode layer 20 includes at least the negative electrode active material layer 22. The negative electrode layer 20 may be substantially composed of, for example, the negative electrode active material layer 22. The negative electrode layer 20 may include, for example, the negative electrode current collector 21 and the negative electrode active material layer 22. The negative electrode current collector 21 may have a thickness of, for example, 5 μm to 50 μm. The negative electrode current collector 21 may contain, for example, a copper (Cu) foil, a nickel (Ni) foil, or the like.

The negative electrode active material layer 22 may have a thickness of, for example, 10 μm to 200 μm. The negative electrode active material layer 22 contains at least the negative electrode active material. The negative electrode active material layer 22 may be substantially composed of, for example, a negative electrode active material. The negative electrode active material layer 22 may contain, for example, a solid electrolyte, a conductive material, a binder, and the like in addition to the negative electrode active material. The negative electrode active material includes, for example, at least one selected from the group consisting of graphite, soft carbon, hard carbon, silicon, silicon oxide, silicon-based alloy, tin, tin oxide, tin-based alloy, and lithium titanate. You may. The solid electrolyte may contain, for example, a sulfide solid electrolyte or the like [for example, LiBr-LiI- (Li _{2 SP 2} S ₅ ) or the like]. The conductive material may contain, for example, a conductive carbon material or the like (for example, VGCF or the like). The binder may contain, for example, PVdF and the like.

《Current collector》
The current collector 60 is in contact with the outer surface of the battery element 50. For example, an adhesive or the like may adhere the outer surface of the battery element 50 to the current collector 60. The adhesive may include, for example, a hot melt adhesive or the like. In order to distinguish from the positive electrode current collector 11 and the negative electrode current collector 21 contained in the battery element 50, the current collector 60 may be referred to as, for example, an "outermost layer current collector" or the like.

The current collector 60 electrically connects the battery element 50 and an external terminal (not shown). The current collector 60 itself may also serve as an external terminal. For example, when the outermost layer of the battery element 50 is the positive electrode layer 10, the current collector 60 has a positive polarity. For example, when the outermost layer of the battery element 50 is the negative electrode layer 20, the current collector 60 has a negative polarity.

The current collector 60 may include, for example, an Al foil, a Ni foil, a Cu foil, or the like. The current collector 60 may have a thickness of, for example, 5 μm to 500 μm.

《Insulation layer》
The insulating layer 70 is arranged between the housing 90 and the current collector 60. The insulating layer 70 may be formed on the surface of the current collector 60, for example. The insulating layer 70 may cover the entire one side of the current collector 60, for example. The insulating layer 70 may cover a part of one side of the current collector 60, for example.

The insulating layer 70 contributes to the insulating resistance between the metal foil 93 and the current collector 60. The insulating layer 70 contains an insulating material. The “insulating material” in the present embodiment indicates a material having a volume resistivity of ^{1 × 10 5 Ω · cm or more at 25 ° C.}

The insulating layer 70 may have a thickness of, for example, 0.1 μm to 100 μm. The thinner the insulating layer 70, the higher the volumetric energy density of the battery 100 is expected. The insulating layer 70 may have a thickness of, for example, 1 μm to 10 μm. The insulating layer 70 may have a thickness of, for example, 1 μm to 5 μm. The insulating layer 70 may have a thickness of, for example, 5 μm to 10 μm.

The insulating layer 70 may be substantially made of an insulating material. The insulating layer 70 may include, for example, a binder or the like in addition to the insulating material. The volume fraction of the insulating material in the insulating layer 70 may be, for example, 50% to 100%. The volume fraction of the insulating material in the insulating layer 70 may be, for example, 80% to 100%. The volume fraction of the insulating material in the insulating layer 70 may be, for example, 90% to 100%.

The insulating material of this embodiment has a Young's modulus of 10 GPa or more. If the Young's modulus of the insulating material is less than 10 GPa, the desired insulation resistance may not be realized when an external force (F) is applied to the battery 100. The insulating material may have, for example, a Young's modulus of 60 GPa or more. The insulating material may have, for example, a Young's modulus of 200 GPa or more. The Young's modulus of the insulating material has an arbitrary upper limit. The insulating material may have, for example, a Young's modulus of 500 GPa or less. The insulating material may have, for example, a Young's modulus of 400 GPa or less.

The Young's modulus of the insulating material may be higher than, for example, the Young's modulus of the positive electrode layer 10 and the negative electrode layer 20. That is, the Young's modulus of the insulating material may be larger than the Young's modulus of the battery element 50. The positive electrode layer 10 and the negative electrode layer 20 may have a Young's modulus of, for example, 3 GPa to 5 GPa.

As the Young's modulus of the insulating material, a literature value can be adopted. For example, "Mechanical Materials" (Asakura Shoten, December 5, 2004, 1st edition, p.195), "Physics" (Shokabo, 2003), "Science Chronological Table 2010 (desktop version)" ) ”(Maruzen Publishing Co., Ltd., 2009, p.379) and the like can be adopted. If the target material has no literature value, the Young's modulus of the target material can be measured by a mechanical test method, a resonance method, or an ultrasonic pulse method.

For reference, the Young's modulus of some materials is shown below.
Diamond-like carbon (DLC): 200 GPa to 500 GPa
Alumina: 50 GPa to 70 GPa
Aluminum anodized: 60 GPa to 80 GPa
Silicon Carbide (SiC): 400 GPa to 500 GPa
Boron Nitride (BN): 10 GPa or more Polypropylene (PP): 1 GPa to 2 GPa
Polyethylene (PE): 0.4 GPa to 1.3 GPa

The insulating material may include, for example, at least one selected from the group consisting of DLC, SiC, aluminum anodized, and BN.

For example, when the current collector 60 is an Al foil, the current collector 60 is anodized (anodized) to form an insulating layer 70 made of anodized aluminum on the surface of the current collector 60. May be done. The insulating layer 70 formed by the alumite treatment is integrated with the current collector 60. Therefore, it is expected that the number of parts will be reduced.

For example, the insulating layer 70 may be formed on the surface of the current collector 60 by a chemical vapor deposition method (CVD), a physical vapor deposition method (PVD), or the like. For example, DLC, ceramic materials, etc. may be deposited on the surface of the current collector 60 by CVD or the like. The insulating layer 70 formed by CVD or the like can also be integrated with the current collector 60.

Hereinafter, examples of the present disclosure (hereinafter, also referred to as “the present examples”) will be described. However, the following description does not limit the scope of claims.

<Manufacturing of all-solid-state batteries>
<< No. 1 >>
1. 1. Formation of negative electrode layer The following materials were prepared.
Negative electrode active material: Silicon (powder)
Solid electrolyte: LiI-LiBr- (Li _{2 SP 2} S ₅ ) (glass ceramics)
Conductive material: VGCF
Binder solution: Solute PVdF (5% by mass), solvent Butyl butyrate Dispersion medium: Butyl butyrate

A PP container was prepared. The above materials were put into a PP container with a predetermined composition. The mixture of the above materials was subjected to a dispersion treatment for 30 seconds by an ultrasonic disperser. The mixture was then shaken by a shaker for 30 minutes. As a result, a negative electrode paste was prepared.

A Cu foil was prepared as a negative electrode current collector. The negative electrode paste was applied to the surface of the negative electrode current collector by a blade type applicator. The negative electrode paste was dried on the hot plate. As a result, a negative electrode active material layer was formed. The set temperature of the hot plate was 100 ° C. The drying time was 30 minutes. From the above, the negative electrode layer was formed. The negative electrode layer included a negative electrode current collector and a negative electrode active material layer.

2. Formation of positive electrode layer The following materials were prepared.
Positive electrode active material: LiNi _1/3 Co _1/3 Mn _1/3 O ₂ (powder) / LiNbO ₃
Solid electrolyte: LiI-LiBr- (Li _{2 SP 2} S ₅ ) (glass ceramics)
Conductive material: VGCF
Binder solution: Solute PVdF (5% by mass), solvent Butyl butyrate Dispersion medium: Butyl butyrate

A positive electrode active material was prepared by coating _{the surface of LiNi 1/3} Co _1/3 Mn _1/3 O ₂ (particles) with LiNbO _3.

The above materials were put into a PP container with a predetermined composition. The mixture of the above materials was subjected to a dispersion treatment for 30 seconds by an ultrasonic disperser. The mixture was then shaken by a shaker for 30 minutes. As a result, a positive electrode paste was prepared.

Al foil was prepared as a temporary support. The positive electrode paste was applied to the surface of the temporary support by a blade type applicator. The positive electrode paste was dried on the hot plate. As a result, a positive electrode active material layer was formed. The set temperature of the hot plate was 100 ° C. The drying time was 30 minutes. From the above, the positive electrode layer was formed. The positive electrode layer consisted of a positive electrode active material layer.

3. 3. Formation of solid electrolyte layer The following materials were prepared.
Solid electrolyte: LiI-LiBr- (Li _{2 SP 2} S ₅ ) (glass ceramics)
Binder solution: Solute butadiene rubber (concentration 5% by mass), solvent heptane Dispersion medium: heptane

The above materials were put into a PP container with a predetermined composition. The mixture of the above materials was subjected to a dispersion treatment for 30 seconds by an ultrasonic disperser. The mixture was then shaken by a shaker for 30 minutes. This prepared a solid electrolyte paste.

Al foil was prepared as a temporary support. The solid electrolyte paste was applied to the surface of the temporary support by a blade-type applicator. The solid electrolyte paste was dried on a hot plate. As a result, a solid electrolyte layer was formed. The set temperature of the hot plate was 100 ° C. The drying time was 30 minutes.

4. Preparation of Battery Element The first laminated body was formed by laminating the solid electrolyte layer and the negative electrode active material layer. The first laminated body was pressed by a roll press machine. The press line pressure was 1 ton / cm (1 × 10 ³ kg / cm). The press temperature was 25 ° C. By press working, the solid electrolyte layer was brought into close contact with the negative electrode active material layer. After the adhesion, the temporary support (Al foil) was peeled off from the first laminated body.

After the temporary support was peeled off, the solid electrolyte layer of the first laminated body and the positive electrode active material layer were bonded to each other to form the second laminated body. The second laminated body was pressed by a roll press machine. The press line pressure was 1 ton / cm. The press temperature was 25 ° C. By press working, the positive electrode active material layer was brought into close contact with the solid electrolyte layer. After the adhesion, the temporary support (Al foil) was peeled off from the second laminated body.

After the temporary support was peeled off, the second laminated body was pressed by a roll press machine. The press line pressure was 4 ton / cm. The press temperature was 150 ° C. As a result, the second laminated body became dense and the battery element was formed.

FIG. 4 is a first schematic plan view for explaining the cutting position of the battery element.
FIG. 4 shows the battery element 50 as viewed from the stacking direction (z-axis direction). The negative electrode active material layer 22 is arranged between the negative electrode current collector 21 and the solid electrolyte layer 30. In FIG. 4, the negative electrode active material layer 22 is not visible.

FIG. 5 is a second schematic plan view for explaining the cutting position of the battery element.
First, the peripheral edge of the positive electrode active material layer 12 was scraped off by a laser. Further, along the dotted line in FIG. 5, the battery element 50 (solid electrolyte layer 30, negative electrode active material layer 22 and negative electrode current collector 21) was cut by a laser.

FIG. 6 is a schematic plan view for explaining the attachment position of the positive electrode current collector.
In the battery element 50 after cutting, the positive electrode current collector 11 was attached to the surface of the positive electrode active material layer 12 by an adhesive. As a result, the battery element 50 with a current collector was prepared. Similarly, a total of 28 battery elements 50 with a current collector were prepared.

Further, two battery elements 50 with an insulating layer were prepared. That is, the surface of the positive electrode current collector 11 in the outermost layer was covered with DLC. As a result, the insulating layer 70 was formed (FIG. 6).

Thirty battery elements 50 were stacked. Insulating layers 70 were attached to the outer surfaces of the battery elements 50 located at both ends in the stacking direction.

After stacking, a plurality of positive electrode current collectors were put together. A positive electrode tab (Al plate) was welded to the positive electrode current collector by ultrasonic waves. Multiple negative electrode current collectors were put together. A negative electrode tab (Ni-plated Cu plate) was welded to the negative electrode current collector by ultrasonic waves. Heat welding tape was attached to each of the positive electrode tab and the negative electrode tab. The heat-welded tape contained a metal foil laminate film and a material that could be heat-welded.

5. A housing made of storage metal foil laminated film was prepared. The first resin film (inside) consisted of a PP layer (40 μm) and a heat-modified PP layer (40 μm). The metal foil consisted of Al foil (thickness 40 μm). The second resin film (outside) consisted of a PET layer (30 μm).

Stainless steel (SUS) particles (spherical, diameter 120 μm) were placed on the surface of the insulating layer (DLC). SUS particles correspond to conductive foreign substances. The battery element was housed in the housing. The housing was vacuum sealed under the condition of -80 kPa. From the above, No. The test battery (all-solid-state lithium-ion battery) according to No. 1 was manufactured.

<< No. 2 to No. 6 >>
Except for the formation of an insulating layer containing the insulating materials shown in Table 1 below, No. As in No. 1, No. 2 to No. The test battery according to No. 6 was manufactured. No. The test battery according to No. 5 does not include an insulating layer.

<Evaluation>
Two metal plates were prepared. The metal plate was made of SUS. The metal plate had a thickness of 25 mm. The test battery was sandwiched between two metal plates. Two metal plates were fixed so that a pressure of 10 MPa was applied to the test battery.

The test battery was placed in a constant temperature bath together with two metal plates. The set temperature of the constant temperature bath was 80 ° C. The test battery was allowed to stand in a constant temperature bath for 72 hours. After standing, the test battery was taken out from the constant temperature bath. The test battery was cooled for 5 hours in a temperature environment of 25 ° C.

After cooling, a part of the second resin film (outside, PET layer) was scraped off in the housing (metal foil laminated film), so that the metal foil was exposed. Insulation resistance was measured between the exposed metal foil and the positive electrode tab. The insulation resistance was measured by an insulation resistance tester. The insulation resistance is shown in Table 1 below. “≧ 5000” in Table 1 below indicates that the insulation resistance is 5000 MΩ or more. When the insulation resistance is 5000 MΩ or more, it can be evaluated that the metal foil in the metal foil laminate film and the current collector are unlikely to be short-circuited.

<Result>
As shown in Table 1 above, when the insulating material contained in the insulating layer has a Young's modulus of 10 GPa or more, an insulating resistance of 5000 MΩ or more is shown.

The present embodiment and the present embodiment are all exemplary. The present embodiment and the present embodiment are not restrictive. For example, it is planned from the beginning that arbitrary configurations are extracted from the present embodiment and the present embodiment and they are arbitrarily combined.

The technical scope defined based on the description of the scope of claims includes all changes in the same sense as the description of the scope of claims. Furthermore, the technical scope defined based on the description of the scope of claims also includes all changes within the scope equivalent to the description of the scope of claims.

1 Conductive foreign matter, 10 Positive electrode layer, 11 Positive electrode current collector, 12 Positive electrode active material layer, 20 Negative electrode layer, 21 Negative electrode current collector, 22 Negative electrode active material layer, 30 Solid electrolyte layer, 50 Battery element, 60 Current collector , 70 Insulation layer, 90 housing, 91 1st resin film, 92 2nd resin film, 93 metal foil, 100 batteries (all-solid-state battery).

Claims (1)

Includes housing, battery elements, current collector, and insulation layer
The housing houses the battery element, the current collector, and the insulating layer.
The housing includes a metal foil laminated film.
The battery element includes a positive electrode layer, a solid electrolyte layer and a negative electrode layer.
The solid electrolyte layer separates the positive electrode layer and the negative electrode layer.
The current collector is in contact with the outer surface of the battery element.
The insulating layer is arranged between the housing and the current collector.
The insulating layer contains an insulating material and contains an insulating material.
The insulating material has a Young's modulus of 10 GPa or more.
All solid state battery.

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