WO2021111551A1 - Electrode member, all-solid-state battery, powder for electrode member, method for manufacturing electrode member, and method for manufacturing all-solid-state battery - Google Patents

Abstract

Provided are: an electrode member with which it is possible to produce an all-solid-state battery using an inexpensive and easy method without necessarily using a previously known high-temperature heat treatment process or vacuum process, the electrode member also being capable of driving the all-solid-state battery thus produced; the all-solid-state battery; a powder for an electrode member; and methods for manufacturing the electrode member and the all-solid state battery. The electrode member comprises: a solid electrolyte layer composed of a sintered compact of an oxide-based solid electrolyte; and a thin-film-form positive electrode active material layer that is positioned on the solid electrolyte layer and is formed of a fine powder composed of an oxide-based positive electrode active material for which the 10% grain diameter (D₁₀) in the cumulative volumetric grain size distribution is 0.01-0.5 µm, the 50% grain diameter (D₅₀) in said cumulative grain size distribution is 0.01-1.0 µm, and the amount of particles having a grain diameter of 0.12 µm or less is 0.5 vol% or greater.

Description

Electrode member, all-solid-state battery, powder for electrode member, method for manufacturing electrode member, and method for manufacturing all-solid-state battery

The present invention relates to an electrode member, an all-solid-state battery, a powder for an electrode member, a method for manufacturing an electrode member, and a method for manufacturing an all-solid-state battery.

The use of all-solid-state batteries as a power source for electric vehicles and small electronic devices is drawing attention. The all-solid-state battery is safer by adopting a solid electrolyte material instead of the liquid electrolyte containing a flammable organic solvent like a conventional lithium-ion battery and making all the constituent parts of the battery solid. Various developments are underway in that a large capacity, high output, and long life can be expected.

For example, Patent Document 1 (Japanese Unexamined Patent Publication No. 2013-149433) describes an example of an all-solid-state battery in which a specific element is solid-solved at the interface between an electrode active material and a solid electrolyte material. Non-Patent Document 1 describes an example of an all-solid-state battery in which a gold layer is introduced at an interface between a solid electrolyte material and an electrode material.

Japanese Unexamined Patent Publication No. 2013-149433

In the production of an all-solid-state battery using an oxide-based solid electrolyte, there is a problem that the interface between the solid electrolyte and the positive electrode active material has a high resistance. For example, when a thin film process is used to form a positive electrode active material, a high temperature heat treatment process or a vacuum process is required to crystallize the thin film. Even when powder is used, high-temperature sintering treatment is required.

However, by carrying out the heat treatment process, a reaction or diffusion phenomenon between the substances occurs at the interface between the solid electrolyte and the positive electrode active material, so that an unintended high resistance layer may be formed.

The techniques described in Patent Document 1 and Non-Patent Document 1 have taken certain measures from the viewpoint of reducing the resistance of the interface between the solid electrolyte and the positive electrode active material, but the manufacturing method is complicated and the manufacturing method is complicated. The cost required for this is also high, and there is still room for consideration.

Therefore, the present invention is an electrode capable of manufacturing an all-solid-state battery having a low internal resistance that can be driven at room temperature by an inexpensive and simple method without necessarily using a conventionally known high-temperature heat treatment process or vacuum process. A member, an all-solid-state battery, a powder for an electrode member, and a method for manufacturing an electrode member and an all-solid-state battery are provided.

On one side, the electrode member according to the embodiment of the present invention is arranged on a solid electrolyte layer made of a sintered body of an oxide-based solid electrolyte and a solid electrolyte layer, and has a 10% particle size in a cumulative particle size distribution based on a volume basis. (D ₁₀ ) is 0.01 μm to 0.5 μm, 50% particle size (D ₅₀ ) is 0.01 μm to 1.0 μm, and the content of particles having a particle size of 0.12 μm or less is 0.5% by volume. It is an electrode member including a thin-film positive electrode active material layer formed of fine powder made of the above oxide-based positive electrode active material.

In the positive electrode active material layer according to the present embodiment, not only the positive electrode active material layer is formed only by the fine powder made of the oxide-based positive electrode active material, but also the desired characteristics required for the positive electrode active material layer are exhibited. Therefore, it goes without saying that a material well known to those skilled in the art may be further contained in the fine powder. For example, a mode in which a carbon material powder and / or a metal powder that further promotes electron conductivity is mixed with a fine powder made of an oxide-based positive electrode active material, and a mode in which a solid electrolyte powder is mixed as a lithium ion conductivity aid. Alternatively, an embodiment of mixing a carbon material powder, a metal powder, and a lithium ion conductive auxiliary agent that further promotes electron conductivity can be mentioned, and it goes without saying that such an embodiment can also be included in the present embodiment. Further, the powder solidified body is not limited to the embodiment composed of a single positive electrode active material fine particles, and it is of course possible to form a single layer or a plurality of layers of a powder solidified body composed of different types of fine particles. Is.

In one embodiment, the electrode member according to the embodiment of the present invention has a solid electrolyte layer of Li _1.5 Al _0.5 Ge _1.5 P ₃ O ₁₂ , Li _0.33 La _0.55 TiO ₃ , Li ₇ La ₃ Zr ₂ O ₁₂ (lithium site). _{The positive electrode active material fine powder contains LiCoO 2} (substitution type of Mg etc. to cobalt site) containing either Al or Ga substitution type to Al or Ga and substitution type such as Nb or Ta to zirconium site. ), LiNi _0.33 Co _0.33 Mn _0.33 O ₂ , LiNi _0.5 Co _0.3 Mn _0.2 O ₂ , LiNi _0.8 Co _0.1 Mn _0.1 O ₂ , LiNi _0.5 Mn _1.5 O ₄ , LiNiO ₂ , LiFePO _4, etc. Any known positive electrode active material such as a metal pyrophosphate composite oxide such as Li ₂ CoP ₂ O _{7 may be used.}

In another aspect, the electrode member according to the embodiment of the present invention is arranged on a solid electrolyte layer made of a sintered body of an oxide-based solid electrolyte and a solid electrolyte layer, and is 10% in the cumulative particle size distribution based on the volume. The particle size (D ₁₀ ) is 0.01 μm to 0.5 μm, the 50% particle size (D ₅₀ ) is 0.01 μm to 1.0 μm, and the content of particles with a particle size of 0.20 μm or less is 5% by mass or more. It is an electrode member including a thin-film (bulk-like) positive electrode active material layer formed of a fine powder made of LiNi _0.5 Mn _1.5 O _{4 of the above.}

The all-solid-state battery according to the embodiment of the present invention is an all-solid-state battery using the electrode member on one side.

On one side, the electrode member powder according to the embodiment of the present invention has a 10% particle size (D ₁₀ ) of 0.01 μm to 0.5 μm and a 50% particle size (D ₅₀ ) in the cumulative particle size distribution based on the volume. A solid composed of an oxide-based positive electrode active material having a particle size of 0.01 μm to 1.0 μm and a particle size of 0.12 μm or less and a content of 0.5% by volume or more, and a sintered body of an oxide-based solid electrolyte. It is a powder for an electrode member for forming a positive electrode active material layer on an electrolyte layer.

_{In one aspect, the method for manufacturing an electrode member according to an embodiment of the present invention has a 10% particle size (D 10} ) in a cumulative particle size distribution on a volume basis on a solid electrolyte layer made of a sintered body of an oxide-based solid electrolyte. Is 0.01 μm to 0.5 μm, the 50% particle size (D ₅₀ ) is 0.01 μm to 1.0 μm, and the content of particles with a particle size of 0.12 μm or less is 0.5% by volume or more. By depositing fine powder made of positive electrode active material, applying a mechanical external force to the surface of the fine powder on the solid electrolyte layer, and causing the fine powder to adhere to each other and solidify, the thin positive electrode active material layer is formed into a solid electrolyte layer. It is a method of manufacturing an electrode member including forming on the surface.

In one embodiment of the method for manufacturing an electrode member according to an embodiment of the present invention, applying a mechanical external force along the surface of the fine powder causes friction between the fine powders or at the interface between the fine powders and the solid electrolyte layer. Including to cause.

In another embodiment, the method for manufacturing an electrode member according to an embodiment of the present invention includes applying a mechanical external force along the surface of the fine powder to rubbing the surface of the fine powder with a friction member.

The method for producing an all-solid-state battery according to the embodiment of the present invention comprises, on one aspect, forming a first metal layer on the positive electrode active material layer formed on the first main surface of the solid electrolyte layer. This is a method for manufacturing an all-solid-state battery, which comprises forming a second metal layer on a second main surface facing the first main surface of the solid electrolyte layer.

In another aspect, the electrode member according to the embodiment of the present invention is arranged on a solid electrolyte layer made of a sintered body of an oxide-based solid electrolyte and a solid electrolyte layer, and is 10% in the cumulative particle size distribution based on the volume. The particle size (D ₁₀ ) is 0.01 μm to 0.5 μm, the 50% particle size (D ₅₀ ) is 0.01 μm to 1.0 μm, and the content of particles having a particle size of 0.12 μm or less is 0.5. It is an electrode member including a bulk-shaped positive electrode mixture layer formed of a mixture of a fine powder made of an oxide-based positive electrode active material in an volume of% or more and a powder made of an oxide-based solid electrolyte.

In one embodiment of the electrode member according to the embodiment of the present invention, the powder made of an oxide-based solid electrolyte is transferred to Li ₇ La ₃ Zr ₂ O ₁₂ (a substitution type of Al or Ga to lithium site, and zirconium site). (Including Nb or Ta substitution type), Li _1.5 Al _0.5 Ge _1.5 P ₃ O ₁₂ , Li ₃ BO ₃ (Li ₃ BO ₃ to Li ₂ SO ₄ , Li ₂ CO ₃ , Li ₄ SiO _{4 of the} material group (Including amorphous or crystallized glass in which one or more of them are mixed), Li _1.3 Al _0.3 Ti _1.7 P ₃ O ₁₂ , Li _0.33 La _0.55 TIO _{3 is} selected from one or more of the group. To.

In another embodiment of the electrode member according to the embodiment of the present invention, the powder made of an oxide-based solid electrolyte has a 50% particle size (D ₅₀ ) of 10 μm or less in the cumulative particle size distribution based on the volume.

In still another embodiment, the electrode member according to the embodiment of the present invention contains 25 to 99% by mass of a powder made of an oxide-based solid electrolyte in the mixture.

According to the present invention, the battery can be driven at room temperature by an inexpensive and simple method without necessarily using a wet process using a conventionally known binder or an organic solvent, a high-temperature heat treatment process, or a vacuum process. A method for manufacturing an electrode member, an all-solid-state battery, a powder for an electrode member, an electrode member, and an all-solid-state battery that can be manufactured not only in an inert atmosphere but also in an air atmosphere. Can be provided.

It is sectional drawing which shows an example of the electrode member which concerns on embodiment of this invention. It is a photograph which shows an example of the fracture surface of the sintered body (LLZ sintered body) of the solid electrolyte layer which concerns on embodiment of this invention. It is a graph which shows an example of the particle size distribution of the fine powder suitable for manufacturing the electrode member which concerns on embodiment of this invention. It is explanatory drawing which shows the state in which the fine powder for forming a positive electrode active material layer (positive electrode mixture layer) 2 is deposited on the solid electrolyte layer 1. It is an electron micrograph which shows an example of the electrode member which concerns on embodiment of this invention. It is a graph which shows the diffraction pattern when the supporting surface of the positive electrode active material layer of an Example is measured by an X-ray diffractometer. It is a graph which shows an example of charge / discharge characteristics of the all-solid-state battery which concerns on embodiment of this invention. It is a Nyquist plot graph which shows an example of the AC impedance measurement result of the all-solid-state battery which concerns on embodiment of this invention. It is an electron micrograph which shows an example of the electrode member which concerns on the modification of embodiment of this invention. It is a graph which shows an example of the AC impedance measurement result of the all-solid-state battery which concerns on embodiment of this invention. It is a Nyquist plot graph which shows an example of the discharge rate characteristic measurement result at room temperature (25 degreeC) of the all-solid-state battery which concerns on embodiment of this invention. It is a graph which shows the charge / discharge characteristic (CV) of Example 4.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The embodiments shown below exemplify an apparatus or a manufacturing method for embodying the technical idea of the present invention, and the technical idea of the present invention describes the structure, arrangement, etc. of each component as follows. It is not specific to the thing.

(First Embodiment)
As schematically shown in FIG. 1, the electrode member according to the embodiment of the present invention includes a solid electrolyte layer 1 made of a sintered body of an oxide-based solid electrolyte and a positive electrode arranged on the surface of the solid electrolyte layer 1. It includes an active material layer 2.

As the solid electrolyte layer 1, a solid electrolyte layer 1 made of an oxidizing solid electrolyte material can be used. Examples of the oxidation-based solid electrolyte material include Li _1.5 Al _0.5 Ge _1.5 P ₃ O _{12 having} a NASICON type crystal structure, Li _0.33 La _0.55 TiO _{3 having a perovskite type crystal structure, and Li 7} La ₃ Zr ₂ O having a garnet type crystal structure. ₁₂ mag is used. Specifically, Li _1.5 Al _0.5 Ge _1.5 P ₃ O ₁₂ , Li _0.33 La _0.55 TiO ₃ , Li ₇ La ₃ Zr ₂ O ₁₂ (replacement type such as Al or Ga to lithium site, and Nb to zirconium site). Alternatively, any of (including a substitution type such as Ta) is preferably used.

Among them, in particular, a cubic lithium lanthanum zirconium oxide (commonly known as "LLZ") represented by _{Li 7} La ₃ Zr ₂ O _{12 having a garnet-type crystal structure (substitution type such as Al or Ga to lithium site, and zirconium site} In addition to the high conductivity of lithium ions, the reactivity with metallic lithium is extremely low compared to other oxide-based solid electrolytes, and dendrite formation by lithium ions is avoided. It is particularly preferably used as an oxidation-based solid electrolyte material for the solid electrolyte layer 1 in that it can form a lithium metal layer directly on the surface of a sintered substrate made of an oxide-based solid electrolyte.

A photograph of the fracture surface of the solid electrolyte layer 1 is shown in FIG. As shown in FIG. 2, the solid electrolyte layer 1 is a sintered body composed of crystal grains having a particle size of approximately 2 to 10 μm based on electron microscopic observation, and grows into larger crystal grains by binding the crystal grains to each other. However, the grain boundary interface is unclear. As shown in FIG. 2, the sintered body of the solid electrolyte layer 1 according to the present embodiment is a dense sintered body and has few pores. Although not limited to the following, the porosity of the solid electrolyte layer 1 is, for example, about 0.1 to 5.0%. The porosity of the solid electrolyte layer 1 can be measured based on, for example, JIS R1634 (1998).

As a result of measuring the AC impedance of the solid electrolyte layer 1 according to the present embodiment, for example, the LLZ sintered body, the solid electrolyte layer 1 has an ion conductivity of about 5.0E-4 to 2.0E-03 (S / cm). Is shown. By adopting such a solid electrolyte layer 1 as a material for the electrode member, the grain boundary resistance of the solid electrolyte layer 1 can be lowered, and the ion conductivity can be improved. By combining such an oxide-based solid electrolyte substrate with the positive electrode active material described below, an all-solid-state battery that can be driven by a cheaper room temperature process without using a conventional high-temperature process or the like can be obtained.

Specific examples of the fine powder used for the positive electrode active material layer 2 include lithium cobalt oxide (LiCoO ₂ ), lithium nickel cobalt manganate (LiNi _0.33 Co _0.33 Mn _0.33 O ₂ , LiNi _0.5 Co _0.3 Mn _0.2 O ₂₎ . LiNi _0.8 Co _0.1 Mn _0.1 O ₂ ), Lithium nickel manganate (LiNi _0.5 Mn _1.5 O ₄ ), Lithium nickel oxide (LiNiO ₂ ), Lithium iron phosphate (LiFePO ₄ ), Lithium cobalt oxide (Li ₂ CoP ₂ O) ₇ ) etc. are available. Above all, it is preferable to use lithium cobalt oxide, lithium nickel cobalt manganate, and lithium nickel manganate as the material of the positive electrode active material layer 2.

The positive electrode active material layer 2 is a fine powder made of an oxide-based positive electrode active material or a powder made of a mixture of an oxide-based positive electrode active material and an oxide-based solid electrolyte powder (hereinafter, also referred to as “positive electrode mixture”). The contained powders are in close contact with each other and solidified, and are composed of a powder solidified body having a thin film shape or a bulk shape. This powder solidified body adheres and solidifies on the surface of a powder containing a fine powder composed of an oxide-based positive electrode active material or a positive electrode mixture by an external mechanical force applied to the powder, and is powdered as if it were a sintered body. It means a layer that is solidified by the binding of grain boundaries and becomes bulky. The production does not necessarily require high temperature conditions (at least 500 ° C. or higher) at the interface with the solid electrolyte layer 1, for example, about room temperature (specifically, about 1 to 30 ° C., more specifically, 15 to 15 to It can be easily produced even under low temperature conditions of 25 ° C.). The method for forming the positive electrode active material layer (positive electrode mixture layer) 2 made of the solidified powder will be described later.

In order to appropriately form the positive electrode active material layer (positive electrode mixture layer) 2 made of a solidified powder on the solid electrolyte layer 1, it is particularly important to appropriately select the properties of the fine powder as a raw material. In the electrode member according to the present embodiment, the plasticity of the fine powder (fine crystal grain superplasticity), the mechanical adhesive force (including the anchor effect) at the fine powder-solid electrolyte layer interface, the chemical adhesive force, or the diffusion adhesive force. Need to be obtained more appropriately. In order to form the solidified powder according to the present embodiment, the higher the ratio of ultrafine powders of less than 100 nm called nanoparticles, the more desirable it is, and in particular, the 10% particle size (D ₁₀ ) in the cumulative particle size distribution based on the volume. It is more preferable to use an oxide-based positive electrode active material having a particle size of 0.01 μm to 0.5 μm and a 50% particle size (D _{50) of 0.01 μm to 1.0 μm as a raw material.}

If the 10% particle size (D ₁₀ ) of the fine powder is larger than 0.5 μm, the fine powders may not adhere well to each other on the solid electrolyte layer 1 and a solidified powder may not be formed. In order to form a more suitable powder solidified body as the positive electrode active material layer (positive electrode mixture layer) 2 of the all-solid-state battery, the _{smaller the average particle size (D 50} ) of the fine powder is, the more preferable it is, and it is 0.15 μm or less. Is more preferable, and even more preferably 0.12 μm or less, and even more preferably 0.1 μm or less. The 10% particle size (D ₁₀ ) of the fine powder is not limited to the following, but is preferably 0.01 μm or more, more preferably 0.02 μm or more, for example, from the viewpoint of handleability and the like.

When lithium cobalt oxide is used as the fine powder, for example, the 10% particle size (D ₁₀ ) is 0.01 to 0.3 μm, further 0.01 to 0.2 μm, and further 0.01 to 0.17 μm. It is preferable to use the fine powder of. When, for example, lithium nickel manganate is used as the fine powder, the 10% particle size (D ₁₀ ) is 0.01 to 0.4 μm, further 0.01 to 0.35 μm, and further 0.01 to 0. It is preferable to use a fine powder of 3 μm. When lithium nickel cobalt manganate is used as the fine powder, a fine powder having a 10% particle size (D ₁₀ ) of 0.01 to 0.5 μm, more preferably 0.01 to 0.3 μm can be used. ..

If the 50% particle size (D ₅₀ ) of the fine powder is larger than 1.0 μm, the fine powders do not adhere well to each other, and the positive electrode active material layer (positive electrode mixture layer) 2 made of the solidified powder has a required thickness. It may not be possible to form. The smaller the 50% particle size (D ₅₀ ) of the fine powder is, the more preferable it is, preferably 0.8 μm or less, still more preferably 0.5 μm or less, and even more preferably 0.3 μm or less. On the other hand, the lower limit of the particle size of the 50% particle size (D ₅₀ ) of the fine powder is not limited to the following, but can be, for example, 0.01 μm or more, further 0.05 μm or more, and the work is easy. From the viewpoint of sex, it is more preferably 0.1 μm or more.

FIG. 3 shows an example of the cumulative particle size distribution of the fine powder suitable as the fine powder used for the positive electrode active material layer (positive electrode mixture layer) 2. As shown in FIG. 3, in the range of 0.01 to 1.4 μm, the 50% particle size (D ₅₀ ) of the cumulative particle size distribution is in the range of 0.01 to 1.0 μm, and further in the range of 0.1 μm to 1.0 μm. It is particularly preferable to use a certain fine powder from the viewpoint of workability.

Further, a fine powder having a ratio (D ₅₀ / D _{10 ) of 50% particle size (D 50} ) to 10% particle size (D ₁₀ ) in the cumulative particle size distribution based on the volume is 3 or less, more preferably 2 or less is used. it is preferred, the ratio of 10% particle size and 90% particle diameter _{(D 90) (D 10)} (D 90 / D 10) of 10 or less, more preferably to use a fine powder is 6 or less.

The fine powder having such characteristics contains a fine powder having a particle size of about 0.12 μm or 0.08 μm or less, which is considered to greatly contribute to the formation of the solidified powder according to the present embodiment, in a predetermined ratio. It is particularly suitable because the solidified powder according to the embodiment can be easily deposited to an appropriate thickness.

For example, when lithium cobaltate, lithium nickel cobalt manganate, or lithium nickel manganate, which are suitable as fine powders, are used, particles having a particle size of 0.12 μm or less are contained in the raw material, for example, by 0.5% by volume or more, preferably 0.5% by volume or more. 2% by volume or more, more preferably 5% by volume or more, and particles having a particle size of 0.08 μm or less are contained in the raw material, for example, 0.1% by volume or more, preferably 0.5% by volume or more, still more preferably 2% by volume. It is preferable to use the fine powder containing the above because the solidified powder can be formed appropriately and easily. The upper limit of the composition ratio of particles having a particle size of 0.12 μm or less in the raw material is not particularly limited, and the larger the particle size, the more preferable.

On the other hand, even if the 10% particle size (D ₁₀ ) and the 50% particle size (D ₅₀ ) are adjusted to appropriate ranges, the particles having a particle size of 0.12 μm or less are, for example, less than 0.5% by volume. Although a small amount of the positive electrode active material layer 2 can be formed, it may not be possible to deposit the positive electrode active material layer 2 to a thickness sufficient to function as the positive electrode active material layer of the all-solid-state battery. Although not limited to the following, the content of particles having a particle size of 0.12 μm or less in the raw material can be preferably 0.5 to 15% by volume, and more preferably 2 to 4% by volume. Is preferable.

When lithium nickel-cobalt manganate is used as a fine powder, even a material containing 5% by volume or more, preferably 10% by volume or more, and more preferably 15% by volume or more of particles having a particle size of 0.20 μm or less. Good. The particle size range suitable for forming the solidified powder varies depending on the type of material used for the fine powder, but in the oxide-based positive electrode active material shown above as the material of the positive electrode active material layer (positive electrode mixture layer) 2. Can be said to be suitably usable as long as it is a fine powder containing 0.5% by volume or more of particles having a particle size of 0.12 μm or less. The content of particles having a predetermined particle size or less is not limited to the above, and the larger the content, the more efficiently the positive electrode active material layer (positive electrode mixture layer) 2 can be formed.

In the present embodiment, the “particle size” refers to a particle size based on a cumulative particle size curve based on the volume of the particle size distribution measured using a laser diffraction / scattering type particle size distribution measuring device. “D ₁₀ ”, “D ₅₀ ” and “D ₉₀ ” indicate 10% particle size, 50% particle size, and 90% particle size, respectively, based on the volume in the cumulative particle size distribution, and are laser diffraction / scattering particle size. In the cumulative particle size curve of the particle size distribution measured using the distribution measuring device, the particle size when the integrated amount occupies 10%, 50%, and 90%, respectively, on a volume basis is shown.

The particle size of the fine powder can be measured using, for example, the laser diffraction / scattering type particle size distribution measuring device "Microtrac MT-3000" manufactured by Microtrac Bell Co., Ltd., and the attached software is used from the measurement results. Then, the cumulative particle size distribution based on the volume can be evaluated.

By using the fine powder having such a distribution, a slight mechanical external force is applied to the surface to cause mechanical adhesion and diffusion adhesion between the fine powders, whereby the positive electrode active material fine powders or the positive electrode described later will be used. The active material fine powder and the oxide solid electrolyte powder can be adhered and fixed. The electrode member thus obtained has good adhesiveness between the solid electrolyte layer 1 and the positive electrode active material layer (positive electrode mixture layer) 2 and can form a low resistance interface. Therefore, the electrode member is an all-solid state using the electrode member. The battery can be sufficiently driven at room temperature. A measuring method known to those skilled in the art can be used for the particle size distribution measurement. The electrode member thus obtained is further heat-treated at 100 to 500 ° C. for 10 seconds to 1 hour in an air atmosphere, an inert atmosphere or an oxygen atmosphere to further solidify the electrolyte layer 1 and the positive electrode active material. It may be possible to reduce the resistance of the interface with the layer (positive electrode mixture layer) 2.

As shown in the schematic view of FIG. 4, in the electrode member according to the embodiment of the present invention, the above-mentioned fine powder is deposited on the surface of the sintered body of the solid electrolyte layer 1 having minute irregularities, and the solid electrolyte layer is formed. As shown in FIG. 1, a thin-film positive electrode active material layer 2 is formed by applying a mechanical external force from above 1 toward the inside of the solid electrolyte layer 1. This was sintered by simply applying pressure to the surface of the nanoparticles (particle size 0.1 μm or less) and the plasticity of the fine powder having a particle size close to the nanoparticles and having a particle size of about 0.1 μm. This utilizes the phenomenon that fine powders are integrated and bulked as described above.

Although it is not intended that the present embodiment is limited by the following inference, the solid electrolyte layer is released with respect to the release of the enormous surface energy of the fine powder and the solid electrolyte layer 1 having a hardness higher than that of the fine powder. By pressing a fine powder having a hardness lower than 1 as a result, densification progresses due to the bonding of the positive electrode active material powder to form a solidified powder, and the powder is uniformly and strongly bonded to the solid electrolyte layer due to an adhesive force such as an anchor effect. It is presumed that a thin interface (powder solidified body) having a certain gloss in appearance is formed by forming an interface.

Various techniques for forming a thin film by applying a mechanical or other external force to a powder or a sintered body thereof have been conventionally known. For example, a method called a vacuum process such as a conventional sputtering method or PLD (pulse laser deposition method) or an aerosol deposition method is used to inject powder at high speed and use the kinetic energy to form a thin film made of powder material on a substrate. is there. In recent years, there have been cases where a thin film is formed on a substrate by these vacuum processes or the aerosol deposition method to realize battery drive, but this is limited to thin film formation technology for extremely small test-level areas, and general-purpose lithium ions. It can be said that the manufacturing process of secondary battery products is an extremely high cost process considering the equipment installation and running costs.

On the other hand, according to the electrode member according to the embodiment of the present invention and the all-solid-state battery using the electrode member, a sintered body of an oxide-based solid electrolyte is used as the solid electrolyte layer 1, and the cumulative amount is accumulated on a volume basis. Particles having a 10% particle size (D ₁₀ ) of 0.01 μm to 0.5 μm, a 50% particle size (D ₅₀ ) of 0.01 μm to 1.0 μm, and a particle size of 0.12 μm or less in the particle size distribution are defined as 0. The positive electrode active material layer 2 is arranged with a thin film-like powder solidified body in which fine powders made of an oxide-based positive electrode active material containing 5% by volume or more and further 5% by volume or more are adhered to each other and solidified. By providing such a configuration, the solid electrolyte layer 1 and the positive electrode active material layer 2 can be joined inexpensively and easily at room temperature without using a vacuum process or the like. Further, it is also possible to drive the obtained all-solid-state battery as a battery at room temperature by producing an all-solid-state battery for the obtained electrode member by, for example, the method shown below.

For example, on the positive electrode active material layer 2 formed on the first main surface which is one surface of the solid electrolyte layer 1 of the electrode member, a metal layer such as gold (Au) is used as the first electrode collecting layer. Is formed. Further, a second negative electrode layer such as metallic lithium (Li) is formed on the second main surface, which is the other surface of the solid electrolyte layer 1 and faces the first main surface, to obtain an all-solid-state battery. .. According to this embodiment, the internal resistance of the obtained all-solid-state battery is as small as 1000 to 5000 Ω · cm ² (when the thickness of the solid electrolyte layer is about 0.5 mm to 1 mm), which is a simpler and cheaper method. Therefore, an electrode member capable of driving a battery at room temperature (25 ° C.), an all-solid-state battery, and a method for manufacturing these can be provided.

A method for manufacturing an electrode member and an all-solid-state battery according to an embodiment of the present invention will be described. First, a solid electrolyte layer 1 is prepared, and the 10% particle size (D ₁₀ ) in the cumulative particle size distribution based on the volume is 0.01 μm to 0.5 μm on the solid electrolyte layer 1, and the 50% particle size (D _50). ) Is 0.01 μm to 1.0 μm, and a fine powder made of an oxide-based positive electrode active material containing 0.5% by volume or more of particles having a particle size of 0.12 μm or less is deposited. The fine powder is deposited over the entire surface on the solid electrolyte layer 1. For example, it is preferable to deposit a total amount of about 0.05 to 10 mg, preferably about 0.1 to 10 mg, on the surface (surface area 100 mm ^{2) of the solid electrolyte layer 1.}

Next, by applying a mechanical external force along the surface of the fine powder on the solid electrolyte layer 1, a solidified powder having a certain film thickness in which the fine powder is in close contact with each other is formed on the surface of the solid electrolyte layer.

As a method of applying a mechanical external force along the surface of the fine powder on the solid electrolyte layer 1, for example, applying a predetermined pressure to the entire surface of the fine powder can be mentioned. For example, by applying a pressure of about 10 kPa to 500 kPa, preferably 20 kPa to 300 kPa, and further about 50 kPa to 200 kPa from the surface of the fine powder, the fine powders are brought into close contact with each other and solidified to form a powder solidified body. A low resistance interface can be formed between the solid electrolyte layer 1 and the solidified powder.

Specifically, it is preferable to apply a mechanical external force so as to cause friction in the fine powder on the solid electrolyte layer 1. For example, there is a method of rubbing the surface of the fine powder with a friction member such as cloth or paper in a predetermined direction. As the friction member, various materials such as paper waste, cloth waste, and resin fiber can be used. When the surface of the fine powder is rubbed with a friction member made of cloth, paper, resin or the like, the rubbing direction is not particularly limited, and the surface may be rubbed in a specific direction or in multiple directions.

According to the method for manufacturing the electrode member and the all-solid-state battery according to the embodiment of the present invention, the production of the positive electrode active material layer does not necessarily require high-temperature heat treatment, and therefore the interface between the solid electrolyte layer 1 and the positive electrode active material layer 2 In, the reaction and diffusion phenomenon between substances can be suppressed, and the formation of an unintended high resistance layer can be suppressed. As a result, an electrode member having a lower resistance can be manufactured.

In addition, by applying pressure to the fine powder to solidify it using a specific fine powder, it can be driven as a solid-state battery more easily and at lower cost than a process using a known aerosol deposition (AD) device or the like. It is possible to manufacture an electrode member of a level that can be produced.

(Second Embodiment)
The electrode member according to another embodiment of the present invention has a 10% particle size (D ₁₀ ) of 0.01 μm to 0.5 μm and a 50% particle size (D ₅₀ ) of 0.01 μm in the cumulative particle size distribution based on the volume. A mixture of a fine powder made of an oxide-based positive electrode active material containing 0.5% by volume or more of particles having a particle size of ~ 1.0 μm and a particle size of 0.12 μm or less and a powder made of an oxide-based solid electrolyte (positive electrode mixture). ) Is prepared, the positive electrode mixture is placed on the solid electrolyte layer 1, and the same predetermined pressure as described above is applied to the entire surface of the positive electrode mixture. Includes forming the material layer 2.

Examples of the powder composed of the oxide-based solid electrolyte include Li _1.5 Al _0.5 Ge _1.5 P ₃ O ₁₂ (LAGP), Li ₃ BO ₃ (LBO) (Li ₃ BO ₃ and Li ₂ SO ₄ ), in addition to the above-mentioned LLZ. Includes amorphous or crystallized glass of one or more of the materials Li ₂ CO ₃ and Li ₄ SiO _{4 ), Li 1.3} Al _0.3 Ti _1.7 P ₃ O ₁₂ (LATP), Li _0.33 Materials selected from any one or more of the group consisting of La _0.55 TiO ₃ (LLTO) can be used, preferably one or two of these solid electrolyte materials.

The particle size of the powder made of the oxide-based solid electrolyte to be added _{is preferably such that the 50% particle size (D 50} ) in the cumulative particle size distribution based on the volume is 10 μm or less, more preferably 5 μm or less.

The optimum composition ratio of the fine powder composed of the oxide-based positive electrode active material in the mixture and the powder composed of the oxide-based solid electrolyte can be adjusted by the combination of materials. It is preferable that the powder composed of the solid electrolyte is contained in an amount of 25 to 99% by volume.

For example, as a fine powder made of an oxide-based positive electrode active material, LCO (lithium cobaltate (LCO)) fine powder (manufactured by Toyoshima Seisakusho Co., Ltd., 10% particle size (D ₁₀ ) 0.097 μm, 50% particle size (D) ₅₀ ) 0.208 μm, 90% particle size (D ₉₀ ) 0.534 μm) is used, and LAGP having an average particle size (D ₅₀ ) of 1.5 μm is mixed as a powder composed of an oxide-based solid electrolyte to prepare a mixture. The interfacial resistance between the solid electrolyte-positive electrode mixture layer when the mixture is prepared and arranged on the solid electrolyte layer 1 to form the positive electrode active material layer 2 shows a tendency as shown in Table 1.

As shown in Table 1, when LCO and LAGP are mixed, LAGP, which is a powder composed of an oxide-based solid electrolyte, is mixed in the mixture by 30 to 50% by mass ratio, and further by mixing 35 to 40%. , The interfacial resistance with the solid electrolyte can be made smaller.

The interface resistance with the solid electrolyte layer 1 may be further reduced by heat-treating the mixture prior to supporting the mixture on the solid electrolyte layer 1 to form the positive electrode active material layer 2. For example, the solid electrolyte layer 1 and the positive electrode active material layer are obtained by heat-treating a raw material in which LCO: LAGP is mixed at a ratio of 75:25 mass% in an oxygen atmosphere at typically 300 to 400 ° C. for 1 to 10 hours. In some cases, the interfacial resistance with 2 can be significantly reduced. The optimum heat treatment conditions differ depending on the combination of materials, but at least the heat treatment temperature must be equal to or lower than the temperature at which the mixed materials cause a reaction. For example, in the case of LCC + LLZ, about 500 ° C., and in the case of LCO + LAGP, about 400 ° C. is the limit temperature at which no chemical reaction (decomposition) occurs between materials, so it is necessary to perform heat treatment below this limit temperature. ..

As a method for producing an electrode member and an all-solid-state battery including the positive electrode active material layer 2 using a mixture of the positive electrode active material fine powder and the solid electrolyte powder, the fine powder made of the above-mentioned oxide-based positive electrode active material was used alone. It is the same as the manufacturing method of the case.

Thus, although the present invention has been described in accordance with the above embodiments, the statements and drawings that form part of this disclosure should not be understood to limit the invention. That is, the present invention is not limited to each embodiment, and the components can be modified and embodied within a range that does not deviate from the gist thereof. In addition, various inventions can be formed by appropriately combining the plurality of components disclosed in each embodiment. For example, some components may be removed from all the components shown in the embodiments. Further, the components of different embodiments may be combined as appropriate.

Examples of the present invention are shown below together with comparative examples, but these examples are provided for a better understanding of the present invention and its advantages, and are not intended to limit the invention.

-Example 1-
(Manufacturing of electrode members)
_{Sandpaper (manufactured by Sankyo Rikagaku Co., Ltd.) with Li 7} La ₃ Zr ₂ O ₁₂ sintered substrate (hereinafter referred to as "LLZ substrate") (size 10 mm x 10 mm x 0.5 mm t) in a glove box with an argon gas atmosphere. After polishing both sides with, the surface of the sintered substrate is fine powder of lithium cobaltate (LCO) (manufactured by Toyoshima Seisakusho Co., Ltd., 10% particle size (D ₁₀ ) 0.097 μm, 50% particle size (D ₅₀ ) 0. Sprinkle 50 mg of particles having a monomodal distribution of FIG. 3 containing particles having a particle size of 208 μm, 90% particle size (D _{90) of 0.534 μm, and a particle size of 0.12 μm or less (11.87% by volume), and a paper waste cloth from above.} The positive electrode active material layer was supported by applying a mechanical external force of 10 kPa to 500 kPa so as to rub it against the LLZ substrate using (manufactured by Nippon Paper Cresia Co., Ltd.). When the supported weight of the positive electrode active material layer formed by the micro balance was measured, it was confirmed that it was 0.25 mg from the difference from the weight of the LLZ substrate measured in advance.

When the surface of the sample carrying the positive electrode active material was measured by an X-ray diffractometer, a diffraction pattern _{derived from LiCoO 2} was confirmed together with the diffraction pattern of the LLZ substrate (FIG. 6). Further, when the cross section of the sample was observed with a scanning electron microscope, it was observed that a film having a certain thickness was formed on the substrate (FIG. 5). From these analysis results, it was confirmed that the positive electrode active material layer made of the powder solidified body of lithium cobalt oxide fine powder was definitely supported on the LLZ substrate.

(Manufacturing of all-solid-state battery)
The following operation was performed to prepare an all-solid-state lithium-ion secondary battery. Au was formed as a collecting electrode on the surface of the electrode member carrying the above-mentioned positive electrode active material on the positive electrode active material layer side by a sputtering device (manufactured by Sanyu Electronics) (thickness: 0.5 μm). On the other hand, a metal Li film was formed as a negative electrode on the opposite surface of the electrode member where Au was formed by a resistance heating vapor deposition machine (thickness: 5 μm).

The above lithium ion secondary battery was installed in a beaker cell, the Au collecting electrode surface was connected to the anode terminal, the Li negative electrode surface was connected to the cathode terminal, and various electrochemical measurements were performed using a potentiogalvanostat device. As a result of performing a charge / discharge test while changing the discharge rate in the order of CC-CV charging (1C → CV 4.2V, 2h charging), 1C, 0.5C, 0.2C, 0.1C, and 1C again, a good battery was obtained. The drive was confirmed (Fig. 7). After charging was completed, impedance measurement (AC impedance measuring device attached to the potential galvanostat device) was performed, and the internal resistance of the all-solid-state battery was about 2 kΩ (FIG. 8).

(Effect of different fine powders on electrode member fabrication)
The above-mentioned method for producing the electrode member and the production of the all-solid-state battery are performed by changing the material of the solid electrolyte layer and the particle size of the fine powder constituting the positive electrode active material layer to be supported on the solid electrolyte layer as shown in Tables 2 to 4. It was evaluated whether or not the electrode member according to the present embodiment could be produced according to the method. The "content rate" in Tables 2 to 4 is obtained from the measurement results of the cumulative particle size distribution based on the volume using the laser diffraction / scattering type particle size distribution measuring device "Microtrac MT-3000" manufactured by Microtrac Bell Co., Ltd. It was.

As shown in Table 2, the 10% particle size (D ₁₀ ) is 0.01 μm to 0.5 μm, the 50% particle size (D ₅₀ ) is 0.01 μm to 1.0 μm, and the particle size is 0.12 μm or less. When a fine powder made of an oxide-based positive electrode active material containing 0.5% by volume or more of particles was used, the positive electrode active material layer could be appropriately formed on the solid electrolyte layer. When the 10% particle size (D ₁₀ ) and 50% particle size (D ₅₀ ) are outside the appropriate range and do not contain particles with a particle size of 0.12 μm or less (rightmost column), a positive electrode active material layer should be formed. I couldn't.

As shown in Table 3, when the nickel manganese acid fine powder was used, the 10% particle size (D ₁₀ ) was 0.01 μm to 0.5 μm, and the 50% particle size (D ₅₀ ) was 0.01 μm to 1. When a fine powder containing 5% by volume or more of particles having a particle size of 0 μm and a particle size of 0.20 μm or less was used (left column), the positive electrode active material layer could be appropriately formed. The material (right column) whose properties of the fine powder were out of the appropriate range could not form the positive electrode active material layer.

As shown in Table 4, the 10% particle size (D ₁₀ ) is 0.01 μm to 0.5 μm, the 50% particle size (D ₅₀ ) is 0.01 μm to 1.0 μm, and the particle size is 0.12 μm or less. When a fine powder made of an oxide-based positive electrode active material containing 0.5% by volume or more of particles was used (left column), the positive electrode active material layer could be appropriately formed on the solid electrolyte layer. When the properties of the fine powder were not within the appropriate range (right column), the positive electrode active material layer could not be formed.

On the other hand, by depositing fine powder of the oxide solid electrolyte on the positive electrode active material layer made of the sintered body of the above-mentioned oxide-based positive electrode active material by the above-mentioned procedure and applying a frictional force, the oxide solid electrolyte can be obtained. When an attempt was made to form a solidified layer, a solid electrolyte layer could not be formed on the positive electrode active material layer.

-Example 2-
(Preparation of positive electrode mixture)
At room temperature (25 ° C.) in the air, the same LCO fine powder as in Example 1 and the LAGP solid electrolyte powder prepared by the solid phase synthesis method were mixed so that the LCO: LAGP ratio was 75:25. A mixed powder was obtained by stirring and mixing for 10 minutes using an agate mortar. The obtained mixed powder was heat-treated at 350 ° C. for 3 hours in an air atmosphere to obtain a positive electrode mixture composed of a mixture of LCO and LAGP.

(Manufacturing of electrode members)
As a solid electrolyte layer, a Ga-doped LLZ (hereinafter referred to as "LLZ substrate") having a relative density of 95% or more, a 10 mm square and a thickness of 1 mm is prepared by a solid-phase synthesis method, and one side of this LLZ substrate is sandpaper. Polishing treatment was performed with (# 400). An appropriate amount of the above-mentioned positive electrode mixture was added to the non-woven fabric, and an external pressure of about 10 kPa to 500 kPa was applied to the polished surface of the LLZ substrate to support about 0.3 mg. The LLZ substrate on which this positive electrode mixture was supported was heat-treated at 350 ° C. for 30 minutes in an air atmosphere to prepare an electrode member. When the cross section of this electrode member was observed with a scanning electron microscope, it was observed that a film having a certain thickness was formed on the substrate (FIG. 9). From these analysis results, it was confirmed that the positive electrode mixture layer formed of the LCO / LAGP mixed fine powder was definitely supported on the LLZ substrate.

(Manufacturing of all-solid-state battery)
After heat treatment, 0.5 μm of Au was formed by sputter deposition on the positive electrode active material layer of the LLZ substrate that was air-cooled to room temperature, and the surface of the LLZ substrate opposite to the Au vapor deposition surface was sanded with sandpaper (# 1000). did. A metal indium sheet was crimped onto the polished surface to form a negative electrode, and an all-solid-state battery was produced.

-Example 3-
An all-solid-state battery was produced by the same method as in Example 2 except that the composition ratio of the positive electrode mixture was LCO: LAGP = 50: 50.

-Example 4-
An all-solid-state battery was produced by the same method as in Example 2 except that the composition ratio of the positive electrode mixture was LCO: LAGP = 65: 35.

-Example 5-
An all-solid-state battery was produced by the same method as in Example 2 except that the composition ratio of the positive electrode mixture was LCO: LAGP = 55: 45.

(Battery characteristic evaluation)
The AC impedance of the all-solid-state battery produced in Examples 2 to 5 was measured with an electrochemical measuring device (VSP-300 manufactured by BioLogic), and the internal resistance of the all-solid-state battery was measured at room temperature (25 ° C.). did. The results are shown in FIG. As shown in FIG. 10, all of Examples 2 to 5 can realize low internal resistance enough to enable battery drive at room temperature, and in particular, Example 4 can realize the lowest internal battery resistance. It was.

For the all-solid-state battery produced in Example 4, charge / discharge characteristics (constant current-constant voltage charge / discharge test, and size) at room temperature (25 ° C) using an electrochemical measuring device (VSP-300 manufactured by BioLogic). Click voltammetry) was measured. The discharge rate characteristic measurement result at room temperature (25 ° C.) of the all-solid-state battery is shown in FIG. 11, and the charge / discharge characteristic (CV) is shown in FIG. In the discharge rate measurement, changes in battery capacity at different discharge rates were investigated with a constant charging current (CCCV discharge combining constant current (50 μA / cm ^{2) -constant voltage (3.58 V 2 hours)).} The discharge was performed in the order of 1 to 7 shown in FIG.

Although the discharge capacity decreased as the current density during discharge increased, a maximum ^{discharge current of 0.5 mA / cm 2} was obtained (see “4” in FIG. 11). In "1", "4", and "7" which were discharged at the same 25 μA / cm ² , the discharge capacity of “4” was almost the same as that of “1”. However, in "7", the discharge capacity is slightly reduced. This is due to a relatively large current of 0.25 mA / cm ² (“5”) to 0.5 mA / cm ² (“6”) in the solid electrolyte layer, in the positive electrode mixture layer, or in the solid electrolyte layer-. It can be considered that the cause is that some resistance component is generated at any or a plurality of interfaces of the positive electrode mixture layer.

1 Solid electrolyte layer 2 Positive electrode active material layer

Claims (13)

1. A solid electrolyte layer made of a sintered body of an oxide-based solid electrolyte,
   Arranged on the solid electrolyte layer, the 10% particle size (D ₁₀ ) is 0.01 μm to 0.5 μm and the 50% particle size (D ₅₀ ) is 0.01 μm to 1.0 μm in the cumulative particle size distribution based on the volume. It is characterized by having a thin-film positive electrode active material layer formed of a fine powder made of an oxide-based positive electrode active material having a particle size of 0.12 μm or less and a content of 0.5% by volume or more. Electrode member to be used.
2. The solid electrolyte layer is Li _1.5 Al _0.5 Ge _1.5 P ₃ O ₁₂ , Li _0.33 La _0.55 TiO ₃ , Li ₇ La ₃ Zr ₂ O ₁₂ (substitution of Al or Ga to lithium site, and Nb to zirconium site). Or including a replacement type of Ta), including
   According to claim 1, the fine powder contains any one of _{LiCoO 2} , LiNi _0.33 Co _0.33 Mn _0.33 O ₂ , LiNi _0.5 Mn _1.5 O ₄ , LiNiO ₂ , LiFePO ₄ , and Li ₂ CoP ₂ O _7. The electrode member described.
3. A solid electrolyte layer made of a sintered body of an oxide-based solid electrolyte,
   Arranged on the solid electrolyte layer, the 10% particle size (D ₁₀ ) is 0.01 μm to 0.5 μm and the 50% particle size (D ₅₀ ) is 0.01 μm to 1.0 μm in the cumulative particle size distribution based on the volume. An electrode member having a thin positive electrode active material layer formed of a fine powder made _{of LiNi 0.5} Mn _1.5 O ₄ having a particle size of 0.20 μm or less and a content of 5% by volume or more. ..
4. An all-solid-state battery using the electrode member according to any one of claims 1 to 3.
5. _{The 10% particle size (D 10} ) is 0.01 μm to 0.5 μm, the 50% particle size (D ₅₀ ) is 0.01 μm to 1.0 μm, and the particle size is 0.12 μm or less in the cumulative particle size distribution based on the volume. Powder for electrode members for forming a positive electrode active material layer on a solid electrolyte layer made of an oxide-based positive electrode active material having a particle content of 0.5% by volume or more and made of a sintered body of an oxide-based solid electrolyte. ..
6. On the solid electrolyte layer made of the sintered body of the oxide-based solid electrolyte, the 10% particle size (D ₁₀ ) in the cumulative particle size distribution based on the volume is 0.01 μm to 0.5 μm, and the 50% particle size (D ₅₀ ) is A fine powder made of an oxide-based positive electrode active material having a particle size of 0.12 μm or less and a particle size of 0.12 μm or less and having a particle size of 0.5% by volume or more is deposited on the solid electrolyte layer. A method for producing an electrode member, which comprises forming a thin-film positive electrode active material layer on the solid electrolyte layer by applying a mechanical external force to the surface of the fine powder to bring the fine powder into close contact with each other and solidify them.
7. The production of the electrode member according to claim 6, wherein applying a mechanical external force along the surface of the fine powder causes friction between the fine powders or at an interface between the fine powders and the solid electrolyte layer. Method.
8. The method for manufacturing an electrode member according to claim 6 or 7, wherein applying a mechanical external force along the surface of the fine powder includes rubbing the surface of the fine powder with a friction member.
9. To form a first metal layer on the positive electrode active material layer formed on the first main surface of the solid electrolyte layer according to any one of claims 6 to 8.
   A method for manufacturing an all-solid-state battery, which comprises forming a second metal layer on a second main surface facing the first main surface of the solid electrolyte layer.
10. A solid electrolyte layer made of a sintered body of an oxide-based solid electrolyte,
    Arranged on the solid electrolyte layer, the 10% particle size (D ₁₀ ) is 0.01 μm to 0.5 μm and the 50% particle size (D ₅₀ ) is 0.01 μm to 1.0 μm in the cumulative particle size distribution based on the volume. A bulk form formed by a mixture of a fine powder made of an oxide-based positive electrode active material having a particle size of 0.12 μm or less and a particle content of 0.5% by volume or more and a powder made of an oxide-based solid electrolyte. An electrode member comprising the positive electrode mixture layer of the above.
11. The powder composed of the oxide-based solid electrolyte is Li ₇ La ₃ Zr ₂ O ₁₂ (including a substitution type of Al or Ga for lithium site and a substitution type of Nb or Ta for zirconium site), Li _1.5 Al _0.5. Ge _1.5 P ₃ O ₁₂ , Li ₃ BO ₃ (Li ₃ BO ₃ mixed with one or more of the materials Li ₂ SO ₄ , Li ₂ CO ₃ , and Li ₄ SiO _{4 in amorphous or crystalline} The electrode member according to claim 10, which is selected from any one or more of the group consisting of (including glass-ceramic), Li _1.3 Al _0.3 Ti _1.7 P ₃ O ₁₂ , Li _0.33 La _0.55 TiO _3.
12. The electrode member according to claim 10 or 11, wherein the powder made of the oxide-based solid electrolyte has a 50% particle size (D _{50) of 10 μm or less in the cumulative particle size distribution based on the volume.}
13. The electrode member according to any one of claims 10 to 12, wherein the powder containing the oxide-based solid electrolyte is contained in the mixture in an amount of 25 to 99% by mass ratio.

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