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EP-4738393-A1 - METHOD FOR PRODUCING HALIDE SOLID ELECTROLYTE, HALIDE SOLID ELECTROLYTE, POSITIVE ELECTRODE MATERIAL, AND BATTERY

EP4738393A1EP 4738393 A1EP4738393 A1EP 4738393A1EP-4738393-A1

Abstract

A production method for a halide solid electrolyte of the present disclosure includes: (A) converting a first composition containing Li, Ti, and O into a first halide containing Li, Ti, and X1; and (B) synthesizing a halide solid electrolyte containing Li, Ti, M, X1, and X2 using the first halide obtained in the (A) and a second halide containing Li, M, and X2. The M is at least one element selected from the group consisting of metal elements (excluding Li) and metalloid elements, the X1 is at least one selected from the group consisting of F, Cl, Br, and I, and the X2 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) converting a first composition containing Li, Ti, and O into a first halide containing Li, Ti, and X1; and (B) synthesizing a halide solid electrolyte containing Li, Ti, M, X1, and X2 using the first halide obtained in the (A) and a second halide containing Li, M, and X2, wherein the M is at least one element selected from the group consisting of metal elements (excluding Li) and metalloid elements and metal elements (excluding Li), the X1 is at least one selected from the group consisting of F, CI, Br, and I, and the X2 is at least one selected from the group consisting of F, CI, Br, and I.
  2. The production method for a halide solid electrolyte according to claim 1, wherein the (A) includes converting a second composition containing Li, M, and O into the second halide, and in the (B), the halide solid electrolyte is synthesized using the first halide and the second halide obtained in the (A).
  3. The production method for a halide solid electrolyte according to claim 1, wherein the (B) includes mixing the first halide and the second halide.
  4. The production method for a halide solid electrolyte according to claim 1, wherein the (B) includes performing heat treatment on the first halide and the second halide.
  5. The production method for a halide solid electrolyte according to claim 1, wherein the (B) includes performing mechanochemical treatment on the first halide and the second halide.
  6. The production method for a halide solid electrolyte according to claim 1, wherein the first halide includes Li 2 TiX1 6 , the second halide includes Li 3 MX2 6 , and 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 TiX1 6 , and composition formula (2): Li 3 MX2 6 .
  7. The production method for a halide solid electrolyte according to claim 1, wherein the M includes Al.
  8. The production method for a halide solid electrolyte according to claim 1, wherein at least one selected from the group consisting of the X1 and the X2 includes F.
  9. The production method for a halide solid electrolyte according to claim 2, wherein in the (A), at least one selected from the group consisting of the following (I) and (II) is performed, (I) conversion of the first composition into the first halide is performed by performing heat treatment on a first halogen-containing substance having thermal decomposition properties, and (II) conversion of the second composition into the second halide is performed by performing heat treatment on a second halogen-containing substance having thermal decomposition properties.
  10. The production method for a halide solid electrolyte according to claim 9, wherein at least one selected from the group consisting of the first halogen-containing substance and the second halogen-containing substance is in particle form.
  11. The production method for a halide solid electrolyte according to claim 9, wherein when the (I) is performed in the (A), the (A) includes (A-1) mixing the first composition and the first halogen-containing substance, and (A-2) converting the first composition into the first halide by performing heat treatment on a mixture including the first composition and the first halogen-containing substance obtained in the (A-1), and when the (II) is performed in the (A), the (A) includes (A-3) mixing the second composition and the second halogen-containing substance, and (A-4) converting the second composition into the second halide by performing heat treatment on a mixture including the second composition and the second halogen-containing substance obtained in the (A-3).
  12. The production method for a halide solid electrolyte according to claim 9, wherein when the (I) is performed in the (A), in the (A), a first halogen gas is generated by performing heat treatment on the first halogen-containing substance, and the first halogen gas is brought into contact with the first composition, thereby converting the first composition into the first halide, and when the (II) is performed in the (A), in the (A), a second halogen gas is generated by performing heat treatment on the second halogen-containing substance, and the second halogen gas is brought into contact with the second composition, thereby converting the second composition into the second halide.
  13. The production method for a halide solid electrolyte according to claim 9, wherein at least one selected from the group consisting of the first halogen-containing substance and the second halogen-containing substance includes an ammonium salt.
  14. The production method for a halide solid electrolyte according to claim 13, wherein the ammonium salt includes NH 4 F.
  15. The production method for a halide solid electrolyte according to claim 9, wherein at least one selected from the group consisting of the first halogen-containing substance and the second halogen-containing substance includes a resin.
  16. The production method for a halide solid electrolyte according to claim 15, wherein the resin includes a fluorine resin.
  17. The production method for a halide solid electrolyte according to claim 9, wherein at least one selected from the group consisting of the first halogen-containing substance and the second 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.
  18. The production method for a halide solid electrolyte according to claim 9, wherein at least one selected from the group consisting of the first halogen-containing substance and the second halogen-containing substance includes a plurality of types of halogen-containing compounds.
  19. A halide solid electrolyte comprising: Li; Ti; Al; F; and at least one selected from the group consisting of K and Fe.
  20. The halide solid electrolyte according to claim 19, being substantially free of TiF 4 .

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) converting a first composition containing Li, Ti, and O into a first halide containing Li, Ti, and X1; and(B) synthesizing a halide solid electrolyte containing Li, Ti, M, X1, and X2 using the first halide obtained in the (A) and a second halide containing Li, M, and X2, wherein the M is at least one element selected from the group consisting of metal elements (excluding Li) and metalloid elements,the X1 is at least one selected from the group consisting of F, CI, Br, and I, andthe X2 is at least one selected from the group consisting of F, CI, 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) converting a first composition containing Li, Ti, and O into a first halide containing Li, Ti, and X1;(B) synthesizing a halide solid electrolyte containing Li, Ti, M, X1, and X2 using the first halide obtained in the (A) and a second halide containing Li, M, and X2. Here, M is at least one element selected from the group consisting of metal elements (excluding Li) and metalloid elements, X1 is at least one selected from the group consisting of F, Cl, Br, and I, and X2 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 is easy to evaporate and also has deliquescence properties, etc. Therefore, the produced halide solid electrolyte may cause compositional variations (i.e., compositional dev