KR-20260063638-A - MANUFACTURING METHOD OF PRECURSOR SOLUTION, SOLID ELECTROLYTE MANUFACTURED THEREBY, AND METHOD FOR MANUFACTURING THE SAME

Abstract

The present invention relates to a method for preparing a precursor solution, a solid electrolyte prepared through the same, and a method for preparing the same. According to one aspect of the present invention, the method comprises a treatment step of treating the precursor in a solvent to induce stirring, grinding, or reaction of at least one precursor including lithium, phosphorus, and sulfur, wherein the treatment step is performed such that the average particle size of the product produced through the treatment step is 5 μm or less.

Inventors

• 정남영
• 임현택
• 유수정
• 최정식
• 김홍석
• 류광현

Assignees

• 주식회사 엔플로우

Dates

Publication Date

20260507

Application Date

20241030

Claims (10)

1. The method includes a processing step of treating the precursor in a solvent to induce stirring, grinding, or reaction of at least one precursor including lithium, phosphorus, and sulfur, and The above processing step is performed such that the average particle size of the product generated through the above processing step is 5 μm or less, Method for preparing a precursor solution.
2. In paragraph 1, The above solvent is an aprotic solvent, Method for preparing a precursor solution.
3. In paragraph 2, The above aprotic solvent comprises at least one selected from the group consisting of acetonitrile, tetrahydrofuran, hexane, and ethyl acetate, Method for preparing a precursor solution.
4. A step of preparing a first precursor solution by treating the first precursor in a first solvent to induce stirring, grinding, or reaction of at least one first precursor including lithium, phosphorus, and sulfur; A step of preparing a second precursor solution by treating at least one second precursor containing a halogen and a second solvent; A step of preparing a mixed solution by mixing the first precursor solution and the second precursor solution; and It includes a synthesis step of synthesizing a solid electrolyte using the above-mentioned mixed solution, and The step of preparing the first precursor solution comprises a step of treating the product in the first precursor solution so that the average particle size is 5 μm or less. Method for manufacturing solid electrolyte.
5. In paragraph 4, The first solvent comprises at least one selected from the group consisting of acetonitrile, tetrahydrofuran, hexane, and ethyl acetate. Method for manufacturing solid electrolyte.
6. In paragraph 4, The above second solvent is an alcohol, Method for manufacturing solid electrolyte.
7. In paragraph 4, The above synthesis step is, A step of forming droplets by spraying the above-mentioned mixed solution; and A method comprising the step of synthesizing the solid electrolyte by heat-treating the above droplet, Method for manufacturing solid electrolyte.
8. When the peak intensities of the (311) and (222) crystal planes and the peak intensities in the range of 33.5˚ to 34.0˚ in the XRD spectrum of a solid electrolyte containing lithium, phosphorus, and sulfur are defined as X, Y, and Z, respectively, Y/X is less than 0.63, and Z/X is less than 0.21, Solid electrolyte.
9. In paragraph 8, The average particle size (D50) of the solid electrolyte, measured by the laser diffraction scattering particle size distribution method, is 6 μm or less, Solid electrolyte.
10. In paragraph 8, The BET specific surface area of the above solid electrolyte is 2.5 m² /g or more, Solid electrolyte.

Description

Manufacturing method of precursor solution, solid electrolyte manufactured thereby, and method for manufacturing the same The present invention relates to a method for preparing a precursor solution, a solid electrolyte prepared through the same, and a method for preparing the same. More specifically, the invention relates to a method for preparing a precursor solution for preparing a solid electrolyte for an all-solid-state battery, a solid electrolyte prepared through the same, and a method for preparing the same. Currently, various studies are underway to increase the energy density and stability of lithium-ion batteries. However, problems such as battery explosions and fires continue to occur due to the excessive increase in energy density of high-voltage batteries. To address these issues, research on all-solid-state batteries utilizing solid electrolytes is actively being conducted. Solid electrolytes required for all-solid-state batteries can be broadly classified into oxide-based, sulfide-based, and polymer-based types; among these, sulfide solid electrolytes are the subject of the most research due to their highest ionic conductivity and numerous process advantages. In addition, solid-phase and liquid-phase methods are used to manufacture solid electrolytes. The solid-state method involves synthesizing electrolyte powder by mixing solid-state starting materials using a ball mill or mixer and then heat-treating them at a high temperature. However, it is difficult to control the particle size of the solid electrolyte, and the non-uniform particle size can lead to a problem where the ionic conductivity of the solid electrolyte decreases. On the other hand, the liquid-phase method using a precursor solution has the advantage of facilitating the dispersion of starting materials and enabling uniform mixing compared to the solid-phase method, so much research is being conducted on it. However, during the process of preparing precursor solutions to generate solid electrolytes, chemical reactions between the precursors forming the solid electrolyte often fail to occur properly. Consequently, the precursors face difficulties in forming an argyrodite structure, resulting in the formation of products with large particle sizes and non-uniformity, which negatively affects the purity and morphology of the solid electrolyte. Furthermore, since the solid electrolyte is not formed intact, a problem arises where the yield of the solid electrolyte is low. Since these problems impair the electrochemical performance and stability of solid electrolytes, technological development is required to overcome them. Meanwhile, the aforementioned background technology is technical information that the inventor possessed for the derivation of the present invention or acquired during the process of deriving the present invention, and it cannot be considered as prior art disclosed to the general public prior to the filing of the present invention. FIG. 1 is a flowchart of a method for manufacturing a solid electrolyte according to one embodiment of the present invention. Figure 2 is a conceptual diagram illustrating an example of a method for manufacturing a solid electrolyte of Figure 1. Figure 3 is a Scanning Electron Microscope (SEM) image of a solid electrolyte according to embodiments of the present invention. Figure 4 is a particle size distribution of a solid electrolyte according to embodiments of the present invention. Figure 5 is an XRD graph of a solid electrolyte according to embodiments of the present invention. Embodiments of the present invention are described below with reference to the attached drawings so that those skilled in the art can easily implement the invention. However, the present invention may be embodied in various different forms and is not limited to the embodiments described herein. Furthermore, in order to clearly explain the present invention in the drawings, parts unrelated to the explanation have been omitted, and similar parts throughout the specification are denoted by similar reference numerals. Throughout the specification, when a part is described as being "connected" to another part, this includes not only cases where they are "directly connected," but also cases where they are "indirectly connected" with other members or elements interposed between them. Furthermore, when a part is described as "including" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components. The present invention will be described in detail below with reference to the attached drawings. The method for preparing a precursor solution, the solid electrolyte prepared thereby, and the method for preparing the same according to the present invention are a method for preparing a precursor solution used as an electrolyte for a lithium-ion battery, a solid electrolyte prepared thereby, and a method for preparing the same. By controlli