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EP-4738386-A1 - METHOD FOR PRODUCING HALIDE SOLID ELECTROLYTE, HALIDE SOLID ELECTROLYTE, POSITIVE ELECTRODE MATERIAL, AND BATTERY

EP4738386A1EP 4738386 A1EP4738386 A1EP 4738386A1EP-4738386-A1

Abstract

A production method for a halide solid electrolyte of the present disclosure includes (A) performing halogenation treatment on an oxide mixture including a composite oxide containing Li and Ti and an oxide raw material containing Li and M, to obtain a halide solid electrolyte containing Li, Ti, M, and X. The M is at least one element selected from the group consisting of metal elements (excluding Li and Ti) and metalloid elements, and the X is at least one selected from the group consisting of F, Cl, Br, and I.

Inventors

  • KOGA, EIICHI

Assignees

  • Panasonic Intellectual Property Management Co., Ltd.

Dates

Publication Date
20260506
Application Date
20240606

Claims (20)

  1. A production method for a halide solid electrolyte, comprising (A) performing halogenation treatment on an oxide mixture including a composite oxide containing Li and Ti and an oxide raw material containing Li and M, to obtain a halide solid electrolyte containing Li, Ti, M, and X, wherein the M is at least one element selected from the group consisting of metal elements (excluding Li and Ti) and metalloid elements, and the X is at least one selected from the group consisting of F, Cl, Br, and I.
  2. The production method for a halide solid electrolyte according to claim 1, wherein the halide solid electrolyte includes a first crystal phase represented by the following composition formula (1) and a second crystal phase represented by the following composition formula (2), composition formula (1): Li 2 TiX 6 , and composition formula (2): Li 3 MX 6 .
  3. The production method for a halide solid electrolyte according to claim 1, wherein the oxide raw material includes an oxide of Li and an oxide of M.
  4. The production method for a halide solid electrolyte according to claim 1, wherein the M includes Al.
  5. The production method for a halide solid electrolyte according to claim 1, wherein the X includes F.
  6. The production method for a halide solid electrolyte according to claim 1, wherein the oxide mixture is in particle form.
  7. The production method for a halide solid electrolyte according to claim 1, wherein the oxide mixture is substantially free of TiO 2 .
  8. The production method for a halide solid electrolyte according to claim 1, wherein in the (A), the halogenation treatment on the oxide mixture is performed by performing heat treatment on a halogen-containing substance having thermal decomposition properties.
  9. The production method for a halide solid electrolyte according to claim 8, wherein the halogen-containing substance is in particle form.
  10. The production method for a halide solid electrolyte according to claim 8, wherein the (A) includes (A-1) mixing the oxide mixture and the halogen-containing substance, and (A-2) performing the halogenation treatment on the oxide mixture by performing heat treatment on a mixture including the oxide mixture and the halogen-containing substance obtained in the above (A-1).
  11. The production method for a halide solid electrolyte according to claim 8, wherein in the (A), a halogen gas is generated by performing heat treatment on the halogen-containing substance, and the halogen gas is brought into contact with the oxide mixture, thereby performing the halogenation treatment on the oxide mixture.
  12. The production method for a halide solid electrolyte according to claim 8, wherein the halogen-containing substance includes an ammonium salt.
  13. The production method for a halide solid electrolyte according to claim 12, wherein the ammonium salt includes NH 4 F.
  14. The production method for a halide solid electrolyte according to claim 8, wherein the halogen-containing substance includes a resin.
  15. The production method for a halide solid electrolyte according to claim 14, wherein the resin includes a fluorine resin.
  16. The production method for a halide solid electrolyte according to claim 8, wherein the halogen-containing substance includes a substance from which inorganic components generated by thermal decomposition during the heat treatment in the (A), other than halogen elements, are substantially not incorporated into the halide solid electrolyte.
  17. The production method for a halide solid electrolyte according to claim 8, wherein the halogen-containing substance includes a plurality of types of halogen-containing compounds.
  18. The production method for a halide solid electrolyte according to claim 1, wherein in the (A), the halogenation treatment on the oxide mixture is performed at a temperature of 150°C or higher.
  19. The production method for a halide solid electrolyte according to claim 1, further comprising (B) performing pulverization treatment on the halide solid electrolyte obtained in the (A), after the (A).
  20. A halide solid electrolyte comprising: Li; Ti; Al; F; and at least one selected from the group consisting of Nb and Ga.

Description

TECHNICAL FIELD The present disclosure relates to a production method for a halide solid electrolyte, a halide solid electrolyte, a positive electrode material, and a battery. BACKGROUND ART Patent Literature 1 discloses a halide-based solid electrolyte material. In addition, Patent Literature 2 discloses a halide-based solid electrolyte material as a solid electrolyte material that coats the surface of a positive electrode active material. CITATION LIST Patent Literature Patent Literature 1: WO 2021/186809Patent Literature 2: WO 2021/187391 SUMMARY OF INVENTION Technical Problem The present disclosure aims to provide a novel production method that allows a halide solid electrolyte having a target composition to be stably synthesized. Solution to Problem A production method for a halide solid electrolyte of the present disclosure includes (A) performing halogenation treatment on an oxide mixture including a composite oxide containing Li and Ti and an oxide raw material containing Li and M, to obtain a halide solid electrolyte containing Li, Ti, M, and X, wherein the M is at least one element selected from the group consisting of metal elements (excluding Li and Ti) and metalloid elements, andthe X is at least one selected from the group consisting of F, Cl, Br, and I. Advantageous Effects of Invention The present disclosure provides a novel production method that allows a halide solid electrolyte having a target composition to be stably synthesized. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a flowchart showing an example of a production method for a halide solid electrolyte according to a first embodiment.FIG. 2 is a flowchart showing an example of a production method for a halide solid electrolyte according to a second embodiment.FIG. 3 is a flowchart showing a modification of the production method for a halide solid electrolyte according to the second embodiment.FIG. 4 is a flowchart showing an example of a production method for a halide solid electrolyte according to a third embodiment.FIG. 5 illustrates a cross-sectional view of a battery 1000 according to a fourth embodiment.FIG. 6A is a graph showing an X-ray diffraction pattern of a halide solid electrolyte after heat treatment and before pulverization treatment in a production method of Example 1.FIG. 6B is a graph showing X-ray diffraction patterns of a halide solid electrolyte after pulverization treatment obtained in Example 1 and a halide solid electrolyte obtained in Comparative Example 1. DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present disclosure will be specifically described with reference to the drawings. The embodiments described below are all comprehensive or specific examples. The numerical values, shapes, materials, components, etc., shown in the following embodiments are examples, and are not intended to limit the present disclosure. In addition, among the components in the following embodiments, the components that are not described in the independent claims that represent broadest concepts are described as discretionary components. [First Embodiment] Hereinafter, a production method for a halide solid electrolyte according to a first embodiment will be described. The production method according to the first embodiment includes (A) performing halogenation treatment on an oxide mixture including a composite oxide containing Li and Ti and an oxide raw material containing Li and M, to obtain a halide solid electrolyte containing Li, Ti, M, and X. Here, M is at least one element selected from the group consisting of metal elements (excluding Li and Ti) and metalloid elements, and X is at least one selected from the group consisting of F, Cl, Br, and I. The "metalloid elements" are B, Si, Ge, As, Sb, and Te. The "metal elements" are all elements included in Groups 1 to 12 of the periodic table (excluding hydrogen) and all elements included in Groups 13 to 16 of the periodic table (excluding B, Si, Ge, As, Sb, Te, C, N, P, O, S, and Se). That is, the "metal elements" are a group of elements that can become cations when halogen compounds and inorganic compounds are formed. With the production method according to the first embodiment, a halide solid electrolyte having a target composition can be stably synthesized. Hereinafter, the reason for this will be described in more detail. In order to produce a halide solid electrolyte containing Ti, a titanium halide (e.g., TiX4) is normally used as a Ti source in a conventional production method. However, a titanium halide is a relatively unstable substance that easily evaporates and also has deliquescence properties, etc. Therefore, the produced halide solid electrolyte may cause compositional variations (i.e., compositional deviation) and alterations (e.g., incorporation of moisture, etc.). Accordingly, in the conventional production method, it may be difficult to stably obtain a target halide solid electrolyte. In contrast, in the production method according to the first embo