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KR-102962470-B1 - New lithium rare earth halide

KR102962470B1KR 102962470 B1KR102962470 B1KR 102962470B1KR-102962470-B1

Abstract

The present invention relates to novel lithium rare earth halides that can be used as solid electrolytes or in electrochemical devices. The present invention also relates to wet and dry processes for the synthesis of such lithium rare earth halides and to lithium rare earth halides that can be obtained by these processes.

Inventors

  • 브라이다, 마르크-다비드

Assignees

  • 사이언스코

Dates

Publication Date
20260511
Application Date
20210412
Priority Date
20200414

Claims (20)

  1. Solid material according to the following general chemical formula I: [Chemical Formula I] Li 6-3x-4y RE x T y X 6 (In the above formula, - X is a halogen and; - 0 < x+(4/3)y <2; 0.8 ≤ x+(4/3)y ≤ 1.5; or 0.95 ≤ x+(4/3)y ≤ 1.25 and; - 0 ≤ y ≤ 0.8; 0.1 ≤ y ≤ 0.7; or 0.2 ≤ y ≤ 0.6 and; - RE represents two or more rare earth metals; the rare earth metals are different from each other; - T is Zr or Hf and; (where y=0 and RE represents two rare earth metals, if one rare earth metal is Y, the other is Yb).
  2. In claim 1, the solid material is any one of the compounds of formulas II to V as follows: [Chemical Formula II] Li 6-3x-4y RE1 a RE2 b T y (In the above equation, a+b=x, where 0.05 ≤ a ≤ 0.95 and 0.0 < b ≤ 0.95; or 0.5 ≤ a ≤ 0.9 and 0.05 < b ≤ 0.5; and if y=0 and RE1 is Y, then RE2 is Yb); [Chemical Formula III] Li 6-3x-4y RE1 a RE2 b RE3 c T y (In the above equation, a+b+c=x, where 0.05 ≤ a ≤ 0.95, 0.0 < b ≤ 0.95 and 0.0 < c ≤ 0.95, and 0.05 ≤ b+c); [Chemical Formula IV] Li 6-3x-4y RE1 a RE2 b RE3 c RE4 d T y (In the above equation, a+b+c+d=x, where 0.05 ≤ a ≤ 0.95, 0.0 < b ≤ 0.95, 0.0 < c ≤ 0.95 and 0.0 < d ≤ 0.95, and 0.05 ≤ b+c+d); [Chemical Formula V] Li 6-3x-4y RE1 a RE2 b RE3 c RE4 d RE5 e T y (In the above equation, a+b+c+d+e=x, where 0.05 ≤ a ≤ 0.95, 0.0 < b ≤ 0.95, 0.0 < c ≤ 0.95, 0.0 < d ≤ 0.95 and 0.0 < e ≤ 0.95, and 0.05 ≤ b+c+d+e); (In the above formula, - X is a halogen and; - 0 < x+(4/3)y <2; 0.8 ≤ x+(4/3)y ≤ 1.5; or 0.95 ≤ x+(4/3)y ≤ 1.25 and; - 0 ≤ y ≤ 0.8; 0.1 ≤ y ≤ 0.7; or 0.2 ≤ y ≤ 0.6 and; - RE1 is selected from the group consisting of Y, Yb, Ho, and Er; - RE2 is selected from the group consisting of Yb, Ho, Gd, Er, Sm, Dy, La, Nd, Ce, Tb; - RE3 is selected from the group consisting of Ho, Gd, Er, Sm, Dy, La, Nd, Ce, and Tb; - RE4 is selected from the group consisting of Er, Gd, Sm, Dy, La, Nd, Ce, and Tb; and - RE5 is selected from the group consisting of Gd, Sm, Dy, La, Nd, Ce, and Tb; where RE1, RE2, RE3, RE4, and RE5 are different; - T is Zr or Hf).
  3. A solid material according to claim 1 or 2, wherein the average ionic radius of RE represents an ionic radius value (unit: Å) smaller than 0.938 Å.
  4. A solid material, wherein X is Cl, in paragraph 1 or 2.
  5. A solid material according to claim 1 or 2, wherein 0.95 ≤ x + (4/3)y ≤ 1.25.
  6. A solid material according to claim 1 or 2, wherein y=0.
  7. A solid material according to claim 1 or 2, selected from the group consisting of Li 3 Y 0.3 Er 0.3 Yb 0.3 Gd 0.1 Cl 6 , Li 3 Y 0.45 Er 0.45 Gd 0.1 Cl 6 ; and Li 3 Y 0.45 Er 0.45 La 0.1 Cl 6 .
  8. A solid material comprising a fraction composed of a glass phase, in accordance with claim 1 or 2.
  9. A solid material in the form of a powder having a particle diameter distribution with a D50 included in 0.05 μm to 10 μm, according to claim 1 or 2.
  10. A method for producing a solid material according to claim 1 or 2, comprising the step of reacting at least a lithium halide and at least two different rare earth metal halides in one or more optional solvents, wherein the rare earth metals in such halides are different from each other and optionally zirconium or hafnium halides.
  11. A process for manufacturing a solid material according to claim 1, comprising the following steps: a) a step of obtaining a composition by mixing stoichiometric amounts of lithium halide and at least two different rare earth metal halides in one or more solvents under an inert atmosphere, wherein the rare earth metals in such halides are different from each other and optionally zirconium or hafnium halides; b) a step of mechanically processing the composition obtained in step a) to obtain a solid material; and c) Optionally, a step of removing at least a portion of one or more solvents from the composition obtained in step b) to obtain a solid material.
  12. As a process for manufacturing a solid material according to the following general chemical formula I: [Chemical Formula I] Li 6-3x-4y RE x T y X 6 (In the above formula, - X is a halogen and; - 0 < x+(4/3)y <2; 0.8 ≤ x+(4/3)y ≤ 1.5; or 0.95 ≤ x+(4/3)y ≤ 1.25 and; - 0 ≤ y ≤ 0.8; 0.1 ≤ y ≤ 0.7; or 0.2 ≤ y ≤ 0.6 and; - RE represents two or more rare earth metals; the rare earth metals are different from each other; - T is Zr or Hf); The above process comprises the following steps: a) a step of obtaining a composition by mixing stoichiometric amounts of lithium halide, at least one rare earth metal halide, and optionally zirconium or hafnium halide in one or more solvents under an inert atmosphere; b) a step of mechanically processing the composition obtained in step a) to obtain a solid material; and c) a step of removing at least a portion of one or more solvents from the composition obtained in step b) to obtain a solid material.
  13. In claim 12, the above-mentioned solid material is any one of the compounds of formulas II to V as follows, process: [Chemical Formula II] Li 6-3x-4y RE1 a RE2 b T y (In the above equation, a+b=x, where 0.05 ≤ a ≤ 0.95 and 0.0 < b ≤ 0.95; or 0.5 ≤ a ≤ 0.9 and 0.05 < b ≤ 0.5); [Chemical Formula III] Li 6-3x-4y RE1 a RE2 b RE3 c T y (In the above equation, a+b+c=x, where 0.05 ≤ a ≤ 0.95, 0.0 < b ≤ 0.95 and 0.0 < c ≤ 0.95, and 0.05 ≤ b+c); [Chemical Formula IV] Li 6-3x-4y RE1 a RE2 b RE3 c RE4 d T y (In the above equation, a+b+c+d=x, where 0.05 ≤ a ≤ 0.95, 0.0 < b ≤ 0.95, 0.0 < c ≤ 0.95 and 0.0 < d ≤ 0.95, and 0.05 ≤ b+c+d); [Chemical Formula V] Li 6-3x-4y RE1 a RE2 b RE3 c RE4 d RE5 e T y (In the above equation, a+b+c+d+e=x, where 0.05 ≤ a ≤ 0.95, 0.0 < b ≤ 0.95, 0.0 < c ≤ 0.95, 0.0 < d ≤ 0.95 and 0.0 < e ≤ 0.95, and 0.05 ≤ b+c+d+e); (In the above formula, - X is a halogen and; - 0 < x+(4/3)y <2; 0.8 ≤ x+(4/3)y ≤ 1.5; or 0.95 ≤ x+(4/3)y ≤ 1.25 and; - 0 ≤ y ≤ 0.8; 0.1 ≤ y ≤ 0.7; or 0.2 ≤ y ≤ 0.6 and; - RE1 is selected from the group consisting of Y, Yb, Ho, and Er; - RE2 is selected from the group consisting of Yb, Ho, Gd, Er, Sm, Dy, La, Nd, Ce, Tb; - RE3 is selected from the group consisting of Ho, Gd, Er, Sm, Dy, La, Nd, Ce, and Tb; - RE4 is selected from the group consisting of Er, Gd, Sm, Dy, La, Nd, Ce, Tb; and - RE5 is selected from the group consisting of Gd, Sm, Dy, La, Nd, Ce, and Tb; where RE1, RE2, RE3, RE4, and RE5 are different; - T is Zr or Hf).
  14. A process according to any one of claims 11 to 13, wherein the lithium halide can be selected from the group consisting of LiCl, LiBr, LiF, and LiI.
  15. A process according to any one of claims 11 to 13, wherein the rare earth metal halide may be selected from the group consisting of YCl3 , ErCl3 , YbCl3 , GdCl3 , LaCl3 , YBr3 , ErBr3 , YbBr3 , GdBr3 , LaBr3 , (Y, Yb, Er) Cl3 , and (La, Y) Cl3 , wherein (Y, Yb, Er) Cl3 is a mixed rare earth halide in which cation sites are occupied by Y, Yb, and Er, and (La, Y) Cl3 is a mixed rare earth halide in which cation sites are occupied by La and Y.
  16. In any one of paragraphs 11 to 13, the zirconium halide is ZrCl₄ , process.
  17. A process according to any one of claims 11 to 13, wherein the solvent is selected from the group consisting of aliphatic hydrocarbons, hexane, pentane, 2-ethylhexane, heptane, decane, cyclohexane, aromatic hydrocarbons, xylene, and toluene.
  18. A process according to any one of claims 11 to 13, wherein in step b), the mechanical treatment is performed by wet or dry milling.
  19. A solid material that can be easily obtained by the process according to paragraph 11.
  20. A solid electrolyte comprising at least one solid material according to any one of claims 1, 2 and 19.

Description

New lithium rare earth halide This application claims priority to European No. 20169464.3 and No. 20169467.6 filed on April 14, 2020, the full contents of each of these applications are incorporated herein by reference for all purposes. The present invention relates to novel lithium rare earth halides that can be used as solid electrolytes or in electrochemical devices. The present invention also relates to wet and dry processes for the synthesis of such lithium rare earth halides and to lithium rare earth halides that can be obtained by these processes. Lithium batteries are used to power portable electronic devices and electric vehicles due to their high energy and power densities. Conventional lithium batteries utilize a liquid electrolyte composed of lithium salts dissolved in an organic solvent. The aforementioned system presents safety issues because the organic solvent is flammable. Lithium dendrites forming and passing through the liquid electrolyte medium can cause short circuits and generate heat, leading to accidents resulting in serious damage. Since the electrolyte solution is a flammable liquid, there is a risk of leakage and ignition when used in batteries. Considering these concerns, there is a need to develop solid electrolytes with a higher degree of safety as next-generation electrolytes for lithium batteries. Non-flammable inorganic solid electrolytes provide a solution to safety issues. Furthermore, their mechanical stability inhibits lithium dendrite formation, prevents self-discharge and heating problems, and helps extend battery life. Glass and glass-ceramic electrolytes are advantageous for lithium battery applications due to their high ionic conductivity and mechanical properties. These electrolytes can be pelletized and attached to electrode materials by cold pressing, which eliminates the need for a high-temperature assembly step. The elimination of the high-temperature sintering step removes one of the challenges associated with using lithium metal anodes in lithium batteries. Due to the widespread use of all-solid-state lithium batteries, there is an increasing demand for solid electrolytes with high conductivity for lithium ions. Recently, rare-earth halide Li₃YCl₆ produced by dry mechanical synthesis has been reported to exhibit improved oxidation stability, particularly up to high potentials , compared to thiophosphate-based electrolytes. However, there is still a need to improve ionic conductivity. Therefore, there is a need for novel solid electrolytes with optimized performance, such as higher ionic conductivity and lower activation energy, without compromising other important properties such as chemical and mechanical stability. Fig. 1: Powder XRD pattern of Li₃YCl₆ obtained by dry mechanochemistry in Example 1 . Fig. 2 : Powder XRD pattern of Li₃GdCl₆ obtained by dry mechanochemistry in Example 2. Fig. 3: Powder XRD pattern of Li₃Y 0.9 Gd 0.1 Cl₆ obtained by dry mechanochemistry in Example 3. Fig . 4: Powder XRD pattern of Li₃Y₆₀Er₆₀Yb₆₀Gd₆₀Cl₆ obtained by dry mechanochemistry in Example 4 . Fig. 5: Powder XRD pattern of Li 2.7 YGd 0.1 Cl 6 obtained by dry mechanochemistry in Example 5. Fig. 6: Powder XRD pattern of Li₃ ( Y₀.45 Er₀.45 Gd₀.1 ) Cl₆ obtained by wet mechanochemistry in Example 6. Fig. 7: Powder XRD pattern of Li₃YCl₆ obtained by wet mechanochemistry in Example 8 . definition Throughout this specification, unless otherwise required by the context, the words “comprise” or “include,” or variations such as “comprising,” “comprising,” “comprising,” and “comprising,” will be understood to imply that they include the mentioned elements or method steps or groups of elements or method steps, but do not exclude any other elements or method steps or groups of elements or method steps. According to a preferred embodiment, the words “comprise” and “comprising,” and variations thereof, mean “to be exclusively composed of.” As used herein, the singular forms (“a,” “an,” and “the”) include plural referents unless the context clearly indicates otherwise. The term “and/or” includes the meanings of “and” and “or,” and all other possible combinations of elements associated with this term. The term "or" should be understood to include a limit. Ratios, concentrations, amounts, and other numerical data may be presented in the form of ranges in this specification. It should be understood that such range forms are used merely for convenience and brevity and should be interpreted flexibly to include not only the numeric values explicitly mentioned as limits of the range, but also all individual numeric values or sub-ranges included within such ranges as if each numeric value and sub-range were explicitly mentioned. For example, a temperature range of about 120°C to about 150°C should be interpreted to include not only the explicitly mentioned limits of about 120°C to about 150°C, but also sub-ranges, e.g., 125°C to 145°C, 130°C to 150°C, etc., and individual amounts (including fract