What is claimed is:
1 . A method of manufacturing a solid electrolyte for an all-solid battery, comprising:
preparing a solvent admixture comprising a first polar organic solvent and a second polar organic solvent; preparing an electrolyte admixture comprising Li 2 S, P 2 S 5 and the solvent admixture; and preparing a solid electrolyte from the electrolyte admixture; wherein, in the forming the solvent admixture, the first polar organic solvent comprises a cyano group, the second polar organic solvent comprises a hydroxyl group, and the first polar organic solvent is different from the second polar organic solvent, and the solvent admixture comprises the second polar organic solvent in an amount of about 0.01 to 0.03 parts by weight based on the total weight of the first polar organic solvent.
2 . The method of claim 1 , further comprising:
precipitating the solid electrolyte; and heat treating the precipitated solid electrolyte.
3 . The method of claim 1 , wherein the electrolyte admixture is prepared by dissolving the Li 2 S and P 2 S 5 in the solvent admixture.
4 . The method of claim 1 , wherein the electrolyte admixture is stirred for preparing the solid electrolyte.
5 . The method of claim 2 , wherein the solid electrolyte is precipitated by evaporating the solvent admixture.
6 . The method of claim 1 , wherein the solid electrolyte emits an amount of 0.25 to 0.4 cm 3 /g of H 2 S gas upon exposure to air.
7 . The method of claim 2 , wherein, in the heat treating the solid electrolyte, the solid electrolyte has an amorphous structure or an argyrodite-type crystal structure.
8 . The method of claim 2 , wherein, in the heat treating the solid electrolyte, the solid electrolyte comprises a metal oxide.
9 . The method of claim 1 , wherein the first polar organic solvent comprises acetonitrile.
10 . The method of claim 1 , wherein the second polar organic solvent comprises one or more selected from the group consisting of methanol, ethanol, and 1-propanol.
11 . The method of claim 1 , wherein the solvent admixture is prepared by stirring at a rotating speed of about 100 to 200 rpm for about 5 to 60 min.
12 . The method of claim 4 , wherein the solid electrolyte is prepared by stirring the electrolyte admixture at a temperature of about 30 to 60° C. for about 1 hr to 48 hr.
13 . The method of claim 1 , further comprising in the preparing the solid electrolyte:
primarily stirring the electrolyte admixture; and secondarily stirring the primarily stirred electrolyte admixture.
14 . The method of claim 13 , wherein the primarily stirring is performed at a rotating speed of about 100 to 150 rpm for about 5 to 10 min.
15 . The method of claim 13 , wherein the secondarily stirring is performed at a rotating speed of about 250 to 300 rpm for about 18 to 36 hr.
16 . The method of claim 5 , wherein the precipitating the solid electrolyte is performed by evaporating the solvent admixture through drying in a vacuum in a temperature range from room temperature to about 80° C. for about 1 hr to 24 hr.
17 . A solid electrolyte manufactured by a method of claim 1 .
18 . An all-solid battery comprising a solid electrolyte of claim 17 .
19 . A vehicle comprising an all-solid battery of claim 18 .