Search

JP-7856578-B2 - Novel lithium rare earth halides

JP7856578B2JP 7856578 B2JP7856578 B2JP 7856578B2JP-7856578-B2

Inventors

  • ブライダ， マルク－ダヴィド

Assignees

  • サイエンスコ エスアー

Dates

Publication Date
20260511
Application Date
20210412
Priority Date
20200414

Claims (20)

  1. Solid materials of the following general formula (I): Li 6-3x-4y RE x T y X 6 (I) (In the formula, - X is a halogen; - 0 < x + (4/3)y <2; preferably 0.8 ≤ x + (4/3)y ≤ 1.5; more preferably 0.95 ≤ x + (4/3)y ≤ 1.25; - 0 ≤ y ≤ 0.8; preferably 0.1 ≤ y ≤ 0.7; more preferably 0.2 ≤ y ≤ 0.6; - RE represents two or more different rare earth metals; - T is either Zr or Hf; (If y = 0 and RE represents two types of rare earth metals, then the condition is that if one rare earth metal is Y, the other is Yb .) The compounds are those of the following formulas (II) to (V): Li 6-3x-4y RE1 a RE2 b T y X 6 (II) (In the formula, a + b = x, and 0.05 ≤ a ≤ 0.95 and 0.0 < b ≤ 0.95; preferably 0.5 ≤ a ≤ 0.9 and 0.05 < b ≤ 0.5; if y = 0 and RE1 is Y, then RE2 is Y b); Li 6-3x-4y RE1 a RE2 b RE3 c T y X 6 (III) (In the equation, a + b + c = x, and 0.05 ≤ a ≤ 0.95, 0.0 < b ≤ 0.95, 0.0 < c ≤ 0.95, and 0.05 ≤ b + c); Li 6-3x-4y RE1 a RE2 b RE3 c RE4 d T y X 6 (IV) (In the equation, a + b + c + d = x, and 0.05 ≤ a ≤ 0.95, 0.0 < b ≤ 0.95, 0.0 < c ≤ 0.95, 0.0 < d ≤ 0.95, and 0.05 ≤ b + c + d); Li 6-3x-4y RE1 a RE2 b RE3 c RE4 d RE5 e T y X 6 (V) (In the equation, a + b + c + d + e = x, and 0.05 ≤ a ≤ 0.95, 0.0 < b ≤ 0.95, 0.0 < c ≤ 0.95, 0.0 < d ≤ 0.95, 0.0 < e ≤ 0.95, and 0.05 ≤ b + c + d + e); A solid material which is one of the following (in these formulas, - X is a halogen; - 0 < x + (4/3)y <2; preferably 0.8 ≤ x + (4/3)y ≤ 1.5; more preferably 0.95 ≤ x + (4/3)y ≤ 1.25; - 0 ≤ y ≤ 0.8; preferably 0.1 ≤ y ≤ 0.7; more preferably 0.2 ≤ y ≤ 0.6; - 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, and 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; - RE5 is selected from the group consisting of Gd, Sm, Dy, La, Nd, Ce, and Tb; RE1, RE2, R3, R4, and RE5 are different; (T is either Zr or Hf).
  2. The solid material according to claim 1, wherein the average ionic radius of RE exhibits an ionic radius value (Å) of less than 0.938 Å.
  3. The solid material according to claim 1 or 2, wherein X is Cl.
  4. A solid material according to any one of claims 1 to 3, wherein 0.95 ≤ x + (4/3)y ≤ 1.25.
  5. A solid material according to any one of claims 1 to 4, wherein y = 0.
  6. A solid material according to any one of claims 1 to 5, selected from the group consisting of Li i 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 .
  7. A solid material according to any one of claims 1 to 6, comprising a fraction consisting of a glass phase.
  8. A solid material according to any one of claims 1 to 7, having a powder form with a particle size distribution containing D50 between 0.05 μm and 10 μm.
  9. A method for producing a solid material according to any one of claims 1 to 8, comprising optionally reacting at least lithium halide with at least two different rare earth metal halides and optionally zirconium or hafnium halide in one or more solvents, wherein the rare earth metals in the rare earth metal halides are different from each other.
  10. A method for preparing a solid material according to any one of claims 1 to 8, a) A step of obtaining a composition by mixing a stoichiometric amount of lithium halide, at least two different rare earth metal halides, and an optional zirconium or hafnium halide in an inert atmosphere and optionally one or more solvents, wherein the rare earth metals in the rare earth metal halides are different from each other; b) A step of performing a mechanical treatment on the composition obtained in step a) in order to obtain the solid material; and c) A step of optionally removing at least a portion of the one or more solvents from the composition obtained in step b) in order to obtain the solid material; A preparation method including the following.
  11. The following general formula (I): Li 6-3x-4y RE x T y X 6 (I) (In the formula, - X is a halogen; - 0 < x + (4/3)y <2; preferably 0.8 ≤ x + (4/3)y ≤ 1.5; more preferably 0.95 ≤ x + (4/3)y ≤ 1.25; - 0 ≤ y ≤ 0.8; preferably 0.1 ≤ y ≤ 0.7; more preferably 0.2 ≤ y ≤ 0.6; - RE represents one or more different rare earth metals; (T is either Zr or Hf) A method for preparing a solid material, a) A step of obtaining a composition by mixing a stoichiometric amount of lithium halide, at least one rare earth metal halide, and an optional zirconium or hafnium halide in one or more solvents under an inert atmosphere; b) A step of performing a mechanical treatment on the composition obtained in step a) in order to obtain the solid material; and c) A step of removing at least a portion of the one or more solvents from the composition obtained in step b) in order to obtain the solid material; A preparation method including the following.
  12. The solid material is a compound of the following formulas (II) to (V): Li 6-3x-4y RE1 a RE2 b T y X 6 (II) (In the formula, a + b = x, and 0.05 ≤ a ≤ 0.95 and 0.0 < b ≤ 0.95; preferably 0.5 ≤ a ≤ 0.9 and 0.05 < b ≤ 0.5); Li 6-3x-4y RE1 a RE2 b RE3 c T y X 6 (III) (In the equation, a + b + c = x, and 0.05 ≤ a ≤ 0.95, 0.0 < b ≤ 0.95, 0.0 < c ≤ 0.95, and 0.05 ≤ b + c); Li 6-3x-4y RE1 a RE2 b RE3 c RE4 d T y X 6 (IV) (In the equation, a + b + c + d = x, and 0.05 ≤ a ≤ 0.95, 0.0 < b ≤ 0.95, 0.0 < c ≤ 0.95, 0.0 < d ≤ 0.95, and 0.05 ≤ b + c + d); Li 6-3x-4y RE1 a RE2 b RE3 c RE4 d RE5 e T y X 6 (V) (In the equation, a + b + c + d + e = x, and 0.05 ≤ a ≤ 0.95, 0.0 < b ≤ 0.95, 0.0 < c ≤ 0.95, 0.0 < d ≤ 0.95, 0.0 < e ≤ 0.95, and 0.05 ≤ b + c + d + e); The method according to claim 11, which is any one of the following: (In these formulas, - X is a halogen; - 0 < x + (4/3)y <2; preferably 0.8 ≤ x + (4/3)y ≤ 1.5; more preferably 0.95 ≤ x + (4/3)y ≤ 1.25; - 0 ≤ y ≤ 0.8; preferably 0.1 ≤ y ≤ 0.7; more preferably 0.2 ≤ y ≤ 0.6; - 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, and 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; - RE5 is selected from the group consisting of Gd, Sm, Dy, La, Nd, Ce, and Tb; RE1, RE2, RE3, RE4, and RE5 are different; (T is either Zr or Hf).
  13. The method according to any one of claims 10 to 12, wherein the lithium halide is preferably selected from the group consisting of LiCl, LiBr, LiF, and LiI.
  14. The method according to any one of claims 10 to 13 , wherein the rare earth metal halide is preferably selected from the group consisting of YCl3 , ErCl3 , YbCl3 , GdCl3 , LaCl3 , YBr3 , ErBr3 , YbBr3 , GdBr3 , LaBr3 , (Y,Yb,Er)Cl3, and (La,Y) Cl3 .
  15. The method according to any one of claims 10 to 14, wherein the zirconium halide is ZrCl4 .
  16. The method according to any one of claims 10 to 15, wherein the solvent is selected from the group consisting of aliphatic hydrocarbons such as hexane, pentane, 2-ethylhexane, heptane, decane, and cyclohexane; and aromatic hydrocarbons such as xylene and toluene.
  17. The method according to any one of claims 10 to 16, wherein in step b), the mechanical treatment is performed by wet or dry milling.
  18. Use of the solid material according to any one of claims 1 to 8 as a solid electrolyte.
  19. A solid electrolyte comprising at least one solid material as described in any one of claims 1 to 8.
  20. An electrochemical device comprising at least one solid electrolyte comprising at least one solid material as described in any one of claims 1 to 8.

Description

This application claims priority under European patents Nr. 20169464.3 and Nr. 20169467.6, filed on April 14, 2020, the entire contents of each of these applications being incorporated herein by reference for all purposes. This invention relates to novel lithium rare-earth halides that can be used as solid electrolytes or in electrochemical devices. The invention also relates to wet and dry processes for synthesizing such lithium rare-earth halides, as well as lithium rare-earth halides readily obtainable by these processes. Lithium batteries are used to power portable electronics and electric vehicles due to their high energy and power density. Conventional lithium batteries utilize a liquid electrolyte composed of lithium salts dissolved in an organic solvent. This system raises safety concerns because the organic solvent is flammable. When lithium dendrites form and pass through the liquid electrolyte medium, they can cause short circuits and generate heat, potentially leading to accidents resulting in serious injury. Because the electrolyte solution is a flammable liquid, there are concerns about leakage, ignition, and other issues when used in batteries. Considering these concerns, the development of solid electrolytes with higher safety features is anticipated as an electrolyte for next-generation lithium batteries. Non-flammable inorganic solid electrolytes offer a solution to safety concerns. Furthermore, their mechanical stability helps suppress lithium dendrite formation, prevent self-discharge and overheating problems, and 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, eliminating the need for high-temperature assembly processes. Eliminating the high-temperature sintering process removes one of the problems associated with using lithium metal anodes in lithium batteries. Due to the widespread use of all-solid-state lithium batteries, there is a growing demand for solid-state electrolytes with high conductivity to lithium ions. In recent years, it has been reported that the rare earth halide Li₃YCl₆ , produced by dry mechanosynthesis , exhibits enhanced oxidative stability at high potentials, particularly compared to thiophosphate-based electrolytes. However, further improvement in ionic conductivity is required. 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 like chemical and mechanical stability. This is the powder XRD pattern of Li₃YCl₆ obtained by dry mechanochemistry in Example 1.This is the powder XRD pattern ofLi₃GdCl₆ obtained by dry mechanochemistry in Example 2.This is the powder XRD pattern of Li3Y0.9Gd0.1Cl6 obtained by dry mechanochemistry in Example 3.This is the powder XRD pattern of Li 3 Y 0.3 Er 0.3 Yb 0.3 Gd 0.1 Cl 6 obtained by dry mechanochemistry in Example 4.This is the powder XRD pattern of Li 2.7 YGd 0.1 Cl 6 obtained by dry mechanochemistry in Example 5.This is the powder XRD pattern of Li3 ( Y0.45Er0.45Gd0.1 ) Cl6 obtained by dry mechanochemistry in Example 6.This is the powder XRD pattern ofLi₃YCl₆ obtained by dry mechanochemistry in Example 8. Examples The following examples are helpful in illustrating the present invention, but are not limiting in nature. X-ray diffraction: XRD diffractograms of powders were acquired using an XRD goniometer with a Bragg Brentano geometry and a Cu X-ray tube (Cu Kalpha wavelength of 1.5406 Å). The setup can be used in different optical configurations, i.e., with variable or fixed divergent slits or Soller slits. Primary-side filtering devices such as a Panalytic monochromator or Bragg Brentano HD optics can also be used. When a variable divergent slit is used, the typical irradiation area is 10 mm × 10 mm. The sample holder is loaded into the spinner; the rotation speed is typically 60 rpm during acquisition. The tube settings were 40 kV/30 mA for variable slit acquisition and 45 kV/40 mA for fixed slit acquisition using the incident Bragg Brentano HD optics. The acquisition process was 0.017° per step. The angular range was typically 5° to 90° for 2 theta or more. The total acquisition time was typically 30 minutes or more. The powder was covered with Kapton film to prevent reaction with moisture in the air. Conductivity Measurement Conductivity was acquired for pellets produced using a uniaxial press operating at 500 MPa. Pelleting was performed using a laboratory-scale uniaxial press in a glove box filled with a moisture-free argon atmosphere. Two carbon paper foils (Mersen Papyex soft graphite N998 Ref: 496300120050000, 0.2 mm thick) were used as current collectors. Measurements were performed in a Swagelok cell closed using a manual spring. Impedance spectra were acquired wi