Method for producing sulfide solid electrolyte
Disclosed is a method for producing a sulfide solid electrolyte including a step of processing a slurry by at least one treatment selected from drying and heating, wherein a solid electrolyte raw material containing a lithium element, a sulfur element, a phosphorus element and a halogen element, and a complexing agent are mixed in a reactor to give a complex slurry containing a complex formed of the solid electrolyte raw material and the complexing agent, and the complex slurry is transferred into an intermediate tank equipped with a cooling device and cooled therein.
1. A method for producing a sulfide solid electrolyte, comprising:
mixing a solid electrolyte raw material and a complexing agent in a reactor to obtain a complex slurry;
transferring the complex slurry to an intermediate tank equipped with a cooling device and cooling the complex slurry therein; and
processing the complex slurry by at least one selected from the group consisting of drying and heating;
wherein:
the solid electrolyte raw material contains a lithium element, a sulfur element, a phosphorus element, and a halogen element;
the complex slurry contains a complex formed of the solid electrolyte raw material and the complexing agent; and
cooling the complex slurry in the intermediate tank comprises storing the complex slurry in the intermediate tank for 0.1 hours or more.
2. The method for producing a sulfide solid electrolyte according to claim 1 , wherein the method further comprises pulverizing the complex, and the complex slurry contains the pulverized complex.
3. The method for producing a sulfide solid electrolyte according to claim 2 , wherein the cooling is carried out after the pulverizing and before the processing.
4. The method for producing a sulfide solid electrolyte according to claim 1 , wherein the cooling is carried out by keeping the complex slurry at a temperature lower than 23° C.
5. The method for producing a sulfide solid electrolyte according to claim 1 , wherein the mixing comprises mixing the solid electrolyte raw material, the complexing agent, and a solvent not dissolving the complex.
6. The method for producing a sulfide solid electrolyte according to claim 5 , wherein the solvent has a solubility parameter 10 or less.
7. The method for producing a solid electrolyte according to claim 1 , wherein the complexing agent contains a compound having a tertiary amino group.
8. The method for producing a solid electrolyte according to claim 1 , wherein the complexing agent contains an aliphatic tertiary diamine having two tertiary amino groups.
9. The method for producing a sulfide solid electrolyte according to claim 8 , wherein the aliphatic tertiary diamine is at least one selected from the group consisting of tetramethylethylenediamine and tetramethyldiaminopropane.
10. The method for producing a sulfide solid electrolyte according to claim 1 , wherein the solid electrolyte raw material contains lithium sulfide and diphosphorus pentasulfide.
11. The method for producing a sulfide solid electrolyte according to claim 1 , wherein the solid electrolyte raw material contains amorphous Li 3 PS 4 or crystalline Li 3 PS 4 .
12. The method for producing a sulfide solid electrolyte according to claim 1 , wherein the solid electrolyte raw material contains lithium bromide.
13. The method for producing a sulfide solid electrolyte according to claim 1 , wherein the sulfide solid electrolyte contains a thio-LISICON Region II-type crystal structure.
14. The method for producing a sulfide solid electrolyte according to claim 4 , wherein the cooling is carried out by keeping the complex slurry at a temperature of 15° C. or lower.
15. The method for producing a sulfide solid electrolyte according to claim 1 , wherein mixing the solid electrolyte raw material and the complexing agent in the reactor comprises mixing in a reactor equipped with an impeller.
16. The method for producing a sulfide solid electrolyte according to claim 1 , wherein processing the complex slurry by at least one selected from the group consisting of drying and heating comprises drying with a drying device.