KR-20260066782-A - Method for manufacturing an all-solid-state battery and an all-solid-state battery

KR20260066782AKR 20260066782 AKR20260066782 AKR 20260066782AKR-20260066782-A

Abstract

A method for manufacturing an all-solid-state battery capable of suppressing bending is provided. A method for manufacturing an all-solid-state battery according to the present invention is a method for manufacturing an all-solid-state battery comprising a positive electrode current collector layer (2), a pair of positive electrode active material layers (3), a pair of solid electrolyte layers (4), and a pair of negative electrode active material layers (5), comprising: a process of preparing a pair of solid electrolyte layers (4) each having a first main surface (4a) and a second main surface (4b) facing each other, made of an oxide solid electrolyte; a process of forming a positive electrode composite layer comprising a positive electrode active material precursor on each first main surface (4a) of the pair of solid electrolyte layers (4) to obtain a pair of solid electrolyte layers with a positive electrode composite attached; a positive electrode forming process of forming a pair of positive electrode active material layers (3) by arranging the pair of solid electrolyte layers with a positive electrode current collector layer (2) so as to face each other and so as to contact each main surface of each positive electrode composite layer and the positive electrode current collector layer (2), and then firing; and a pair of solid The process includes a cathode forming process for forming a cathode active material layer (5) on each second main surface (4b) of the electrolyte layer (4).

Inventors

이케지리 준이치
츠노다 케이
타나카 아유무
야마우치 히데오
카노 겐타로

Assignees

니폰 덴키 가라스 가부시키가이샤

Dates

Publication Date: 20260512
Application Date: 20250131
Priority Date: 20240215

Claims (14)

A method for manufacturing an all-solid-state battery comprising a positive current collector layer, a pair of positive active material layers, a pair of solid electrolyte layers, and a pair of negative active material layers, A process for preparing a pair of solid electrolyte layers, each having a first main surface and a second main surface facing each other, and comprising an oxide solid electrolyte. A process for forming an anode composite layer comprising an anode active material precursor on each of the first main surfaces of a pair of solid electrolyte layers to obtain a pair of solid electrolyte layers with an anode composite attached, and A positive electrode formation process for forming a pair of positive electrode active material layers by arranging a pair of solid electrolyte layers with the above positive electrode composite attached so as to face each other with the positive electrode current collector layer in between, and so as to contact each main surface of each of the above positive electrode composite layer and the above positive electrode current collector layer, and then firing; A method for manufacturing an all-solid-state battery, comprising a cathode forming process for forming the cathode active material layer on each of the second main surfaces of a pair of solid electrolyte layers.
In Article 1, A method for manufacturing an all-solid-state battery in which the thickness of the positive electrode active material layer is thicker than the thickness of the negative electrode active material layer.
In Article 1, A method for manufacturing an all-solid-state battery, wherein, in the above-described positive electrode formation process, a laminate of a pair of positive electrode composite-attached solid electrolyte layers and a positive electrode current collector layers is fired while applying a load in the stacking direction to the laminate.
A method for manufacturing an all-solid-state battery comprising a negative electrode current collector layer, a pair of positive electrode active material layers, a pair of solid electrolyte layers, and a pair of negative electrode active material layers, A process for preparing a pair of solid electrolyte layers, each having a first main surface and a second main surface facing each other, and comprising an oxide solid electrolyte; A cathode composite layer formation process for obtaining a pair of solid electrolyte layers with attached cathode composites by forming a cathode composite layer comprising a cathode active material precursor on each of the first main surfaces of a pair of solid electrolyte layers, and A cathode forming process for forming a pair of cathode active material layers by arranging a pair of solid electrolyte layers attached with the cathode composite material so as to face each other with the cathode current collector layer in between, and so as to contact the respective main surfaces of each cathode composite material layer and the cathode current collector layer, and then firing; A method for manufacturing an all-solid-state battery, comprising a positive electrode forming process for forming the positive electrode active material layer on each of the second main surfaces of a pair of solid electrolyte layers.
In Article 4, A method for manufacturing an all-solid-state battery, wherein, in the above-described cathode formation process, a stack of a pair of cathode composite-attached solid electrolyte layers and a cathode current collector layer is sintered while applying a load in the stacking direction to the stack.
In Article 1 or Article 4, A method for manufacturing an all-solid-state battery, wherein the solid electrolyte layer is composed only of a dense layer and the thickness of the solid electrolyte layer is 70 μm or less.
In Article 1 or Article 4, A method for manufacturing an all-solid-state battery in which the solid electrolyte layer has a dense layer and a porous layer, and the dense layer and the porous layer are stacked.
In Article 7, A method for manufacturing an all-solid-state battery in which the thickness of the dense layer is 70㎛ or less.
In Article 7, A method for manufacturing an all-solid-state battery in which the total thickness of the dense layer and the porous layer is 170 μm or less.
In Article 1 or Article 4, A method for manufacturing an all-solid-state battery, wherein the cathode forming process is performed prior to the anode forming process.
In Article 1 or Article 4, A method for manufacturing an all-solid-state battery comprising a positive active material made of crystallized glass, wherein the positive active material layer is represented by the general formula Na x M y P 2 O z , and contains a crystal in which 1≤x≤2.8, 0.95≤y≤1.6, 6.5≤z≤8, and M is at least one selected from the group consisting of Fe, Ni, Co, Mn, and Cr.
In Article 1 or Article 4, A method for manufacturing an all-solid-state battery comprising a negative electrode active material layer made of hard carbon.
In Article 1 or Article 4, A method for manufacturing an all-solid-state battery, wherein the oxide solid electrolyte comprises at least one selected from the group consisting of β-alumina, β"-alumina, and NASICON crystals.
An all-solid-state battery comprising a positive current collector layer of one layer, a positive active material layer of two layers, a solid electrolyte layer of two layers, and a negative active material layer of two layers, The above positive current collector layer has a first main surface and a second main surface facing each other, and The above positive active material layer comprises a positive active material made of crystallized glass, wherein the positive active material layer is represented by the general formula Na x M y P 2 O z , 1 ≤ x ≤ 2.8, 0.95 ≤ y ≤ 1.6, 6.5 ≤ z ≤ 8, and M is at least one selected from the group consisting of Fe, Ni, Co, Mn, and Cr. The above solid electrolyte layer is composed of an oxide solid electrolyte comprising at least one selected from the group consisting of β-alumina, β"-alumina, and NASICON crystals, and The above-mentioned negative electrode active material layer comprises a negative electrode active material made of hard carbon, and The positive active material layer is laminated on each of the first main surface and the second main surface of the positive current collector layer, and The solid electrolyte layer is laminated on the main surface opposite to the side where the positive current collector layer of each of the above positive active material layers is formed, and A solid-state battery formed by stacking a negative electrode active material layer on the main surface opposite to the side where the positive electrode active material layer is formed on each of the above-mentioned solid electrolyte layers.

Description

Method for manufacturing an all-solid-state battery and an all-solid-state battery The present invention relates to a method for manufacturing an all-solid-state battery and an all-solid-state battery. Lithium-ion rechargeable batteries have established themselves as indispensable, high-capacity, and lightweight power sources for mobile devices and electric vehicles. However, conventional lithium-ion rechargeable batteries primarily use flammable organic electrolytes, raising concerns about risks such as fire. As a solution to this problem, the development of all-solid-state lithium-ion batteries using solid electrolytes instead of organic electrolytes is underway. Furthermore, as there are concerns regarding the global supply of lithium raw materials, the development of all-solid-state sodium-ion batteries is also progressing. Patent Document 1 below discloses an example of an all-solid-state lithium secondary battery. In this lithium secondary battery, a positive electrode composite layer, a solid electrolyte layer, and a negative electrode composite layer are stacked in this order. A positive current collector is installed on the surface of the positive electrode composite layer. A negative current collector is installed on the surface of the negative electrode composite layer. Examples of materials for the solid electrolyte layer include perovskite-type oxides, NASICON-type oxides, and LISICON-type oxides. FIG. 1 is a schematic cross-sectional view showing an all-solid-state battery according to one embodiment of the present invention. FIG. 2 is a schematic cross-sectional view showing an all-solid-state battery according to an embodiment different from the embodiment shown in FIG. 1 of the present invention. FIG. 3 is a schematic cross-sectional view showing a solid electrolyte layer in an embodiment of FIG. 1 of the present invention. FIGS. 4(a) to 4(c) are schematic cross-sectional views for explaining the second electrode forming process and the electrode composite layer forming process, etc., in the method for manufacturing an all-solid-state battery according to the first embodiment of the present invention. FIGS. 5(a) to 5(c) are schematic cross-sectional views for explaining the first electrode forming process, etc., in the method for manufacturing an all-solid-state battery according to the first embodiment of the present invention. FIGS. 6(a) and FIGS. 6(b) are schematic cross-sectional views illustrating a method for manufacturing an all-solid-state battery of a comparative example. Figure 7 is a photograph of an all-solid-state battery manufactured by the manufacturing method of a comparative example. FIG. 8(a) is a photograph of an all-solid-state battery produced by a method for manufacturing an all-solid-state battery according to an embodiment of the present invention, taken from the negative electrode active material layer side. FIG. 8(b) is a photograph of the all-solid-state battery shown in FIG. 8(a) taken from the side. FIG. 9 is a schematic cross-sectional view illustrating that forces acting on an all-solid-state battery produced by the method of manufacturing an all-solid-state battery according to the first embodiment of the present invention cancel each other out. FIG. 10 is a schematic cross-sectional view illustrating an example in which, in the first electrode forming process, a laminate of a pair of electrode composites, a solid electrolyte layer and an anode current collector layer is sintered while applying a load in the lamination direction. FIGS. 11(a) to 11(d) are schematic cross-sectional views for explaining the second electrode forming process, the electrode composite layer forming process, and the first electrode forming process in a method for manufacturing an all-solid-state battery according to a modified example of the first embodiment of the present invention. FIGS. 12(a) and FIGS. 12(b) are schematic cross-sectional views for explaining the electrode composite layer formation process, etc., in the method for manufacturing an all-solid-state battery according to the second embodiment of the present invention. FIGS. 13(a) and FIGS. 13(b) are schematic cross-sectional views for explaining the first electrode forming process and the second electrode forming process, etc., in the method for manufacturing an all-solid-state battery according to the second embodiment of the present invention. FIG. 14 is a drawing showing a solid electrolyte layer used in a method for manufacturing an all-solid-state battery according to a third embodiment of the present invention. Preferred embodiments are described below. However, the following embodiments are merely examples, and the present invention is not limited to the following embodiments. Additionally, in each drawing, components having substantially the same function may be referred to by the same reference numerals. (Solid-state battery) FIG. 1 is a schematic cross-sectional view showing an all-solid-state battery accordi