Search

CN-122010178-A - Novel sulfide solid electrolyte preparation method

CN122010178ACN 122010178 ACN122010178 ACN 122010178ACN-122010178-A

Abstract

The invention discloses a novel sulfide solid electrolyte preparation method, relates to the technical field of sulfide solid electrolytes, and solves the problems of low ionic conductivity and unstable electrochemical performance of the existing high-chloride sulfide solid electrolyte caused by basically determined lithium phosphorus sulfur chlorine structure, components and content. The method comprises the following steps of S1, weighing and mixing a lithium source, a phosphorus source, a sulfur source and a metal halide dopant as raw materials to obtain a mixture, S2, putting the mixture into ball milling equipment for grinding and crushing to obtain a precursor mixture, and S3, taking out the precursor mixture and pressing the precursor mixture into a tablet shape to obtain an electrolyte embryo. According to the invention, through a high-temperature annealing process after high-speed ball milling, elements with larger ionic radius are introduced from a raw material end in the sulfide electrolyte synthesis process to dope instead of P-site elements, and the novel sulfide solid electrolyte with high ionic conductivity and good electrochemical stability is prepared and obtained.

Inventors

  • Lv Fengzheng

Assignees

  • 深圳固丰硅科新材料有限公司

Dates

Publication Date
20260512
Application Date
20260210

Claims (9)

  1. 1. A preparation method of a novel sulfide solid electrolyte is characterized by comprising the following steps: S1, weighing and mixing a lithium source, a phosphorus source, a sulfur source and a metal halide dopant serving as raw materials to obtain a mixture; S2, putting the mixture into ball milling equipment for grinding and crushing to obtain a precursor mixture; S3, taking out the precursor mixture, and pressing the precursor mixture into a tablet to obtain an electrolyte embryo; s4, placing the electrolyte blank in a high-temperature furnace for annealing treatment; and S5, crushing the annealed electrolyte blank to obtain sulfide solid electrolyte powder.
  2. 2. The method of preparing a novel sulfide solid state electrolyte as claimed in claim 1, wherein the metal halide dopant is a doping substitution element, the lithium source, the phosphorus source and the sulfur source are substitution elements, the lithium source comprises but is not limited to LiCl and Li 2 S, the phosphorus source comprises but is not limited to P 2 S 5 , the sulfur source comprises but is not limited to Li 2 S and P 2 S 5 , and the metal halide dopant comprises but is not limited to at least one of TaCl 5 、NbCl 5 、LaCl 3 .
  3. 3. The method for preparing the novel sulfide solid electrolyte according to claim 2, wherein the ball milling equipment comprises a turntable bracket and a ball milling tank, the ball milling tank is a sealed ball milling tank with an agate liner, and agate ball milling beads are arranged in the ball milling tank; The mass ratio of the mixture to the agate ball-milling beads is 1:10, the agate ball-milling beads comprise three different particle sizes of 3mm, 5mm and 10mm, the mass ratio of the agate ball-milling beads from small particle size to large particle size is 1:3:6, the ball-milling equipment runs for 20min at an initial rotation speed of 200rpm, and then regulating the rotating speed to 600rpm, stopping for 10min after each 30min of running at 600rpm, stopping for 10min after the rotating is continued for 30min at the same rotating speed in the opposite direction, and circulating for 5 times in the forward and reverse directions at 600 rpm.
  4. 4. The method for preparing a novel sulfide solid electrolyte as claimed in claim 3, wherein the doping substitution element accounts for 0-30% of the substituted element in mole ratio.
  5. 5. The method for preparing a novel sulfide solid electrolyte as claimed in claim 4, wherein the doping substitution element accounts for 0-10% of the substituted element in mole ratio.
  6. 6. The method for preparing a novel sulfide solid electrolyte as claimed in claim 5, wherein the doping substitution element accounts for 0.5-6.5% of the substituted element in mole ratio.
  7. 7. The method for preparing a novel sulfide solid state electrolyte according to any one of claims 4 to 6, wherein the high temperature furnace is annealed at 305 to 600 ℃ for 1 to 8 hours.
  8. 8. The method for preparing a novel sulfide solid electrolyte according to claim 7, wherein the high-temperature furnace annealing temperature is 400-550 ℃ and the annealing time is 2-6 hours.
  9. 9. The method for preparing a novel sulfide solid electrolyte according to claim 8, wherein the high-temperature furnace annealing temperature is 420-500 ℃ and the annealing time is 3-5 hours.

Description

Novel sulfide solid electrolyte preparation method Technical Field The invention relates to the technical field of sulfide solid electrolyte, in particular to a novel sulfide solid electrolyte preparation method. Background The sulfide solid electrolyte is a core key material of the all-solid battery, is an inorganic solid electrolyte material taking sulfur as a main component, is used in the all-solid battery to replace the traditional liquid electrolyte so as to improve the safety and energy density of the battery, and comprises a sulfur silver germanium ore type (such as Li 6PS5 Cl) and a lithium germanium phosphorus sulfur type (such as Li 10GeP2S12), wherein the sulfur silver germanium ore type is widely focused due to excellent comprehensive performance, is widely applied to the field of solid battery production and preparation, and is the most applied sulfide solid electrolyte in the solid battery. The structure, the components and the content of the lithium phosphorus sulfur chlorine of the existing high-chlorine sulfide solid electrolyte are basically determined, so that the ionic conductivity and the electrochemical performance of the high-chlorine sulfide solid electrolyte are not high, the existing requirements are not met, and a novel sulfide solid electrolyte preparation method is provided. Disclosure of Invention The invention aims to provide a novel sulfide solid electrolyte preparation method, which aims to solve the problems that the existing high-chloride sulfide solid electrolyte has basically determined lithium phosphorus sulfur chlorine structure, components and content, and the ionic conductivity and the electrochemical performance of the high-chloride sulfide solid electrolyte are not high. In order to achieve the above purpose, the invention provides a novel sulfide solid electrolyte preparation method, which comprises the following steps: S1, weighing and mixing a lithium source, a phosphorus source, a sulfur source and a metal halide dopant serving as raw materials to obtain a mixture; S2, putting the mixture into ball milling equipment for grinding and crushing to obtain a precursor mixture; S3, taking out the precursor mixture, and pressing the precursor mixture into a tablet to obtain an electrolyte embryo; s4, placing the electrolyte blank in a high-temperature furnace for annealing treatment; and S5, crushing the annealed electrolyte blank to obtain sulfide solid electrolyte powder. Preferably, the metal halide dopant is a doped substitutional element, the lithium source including but not limited to LiCl and Li 2 S, the phosphorus source including but not limited to P 2S5, the sulfur source including but not limited to Li 2 S and P 2S5, and the metal halide dopant including but not limited to at least one of TaCl 5、NbCl5、LaCl3. Preferably, the doping substitution element accounts for 0-30% of the molar ratio of the substituted element. Preferably, the doping substitution element accounts for 0-10% of the molar ratio of the substituted element. Preferably, the doping substitution element accounts for 0.5-6.5% of the molar ratio of the substituted element. Preferably, the annealing temperature of the high-temperature furnace is 305-600 ℃, and the annealing time is 1-8 hours. Preferably, the annealing temperature of the high-temperature furnace is 400-550 ℃, and the annealing time is 2-6 hours. Preferably, the annealing temperature of the high-temperature furnace is 420-500 ℃, and the annealing time is 3-5 hours. Preferably, the ball milling equipment comprises a turntable bracket and a ball milling tank, the ball milling tank is a sealed ball milling tank with an agate liner, agate ball milling beads are arranged in the ball milling tank, the mass ratio of a mixture to the agate ball milling beads is 1:10, the agate ball milling beads comprise three different particle sizes of 3mm, 5mm and 10mm, the mass ratio of the agate ball milling beads is 1:3:6 from small particle size to large particle size, the ball milling equipment is operated for 20min at an initial rotation speed of 200rpm, then the ball milling equipment is adjusted to be stopped for 10min after each 30min under the rotation speed of 600rpm, and is stopped for 10min after the agate ball milling beads continue to rotate for 30min along the opposite direction at the same rotation speed, and the agate ball milling equipment is circulated for 5 times in the positive and negative directions under the rotation speed of 600 rpm. Compared with the prior art, the invention has the beneficial effects that: 1. According to the invention, one or more of metal halides MClx (M=Ta, nb and La; x=3-6) are added into an initial raw material, and after the treatment of the initial raw material by the methods of subsequent ball milling mixing, high-temperature annealing and the like, a novel sulfide solid electrolyte is obtained, the ionic conductivity of the sulfide solid electrolyte is higher than that of a high-chlorine lithium pho