Patent ID: 7438837

Claim:
A method of producing a solid electrolyte comprising: preparing solid electrolyte material with a composition expressed by a formula: (1−x) ZrO 2 +xSc 2 O 3 (where x is a number equal to or greater than 0.05 and equal to or less than 0.15); and sintering the solid electrolyte material to obtain a solid electrolyte using a spark plasma method, which is provided with: sintering the solid electrolyte material to obtain sintered material while applying a first compression load to the solid electrolyte material at a level equal to or less than 40 MPa; and cooling the sintered material to obtain the solid electrolyte while applying a second compression load, less than the first compression load, to the sintered material, wherein the second compression load has a value equal to or greater than 10 MPa and equal to or less than 15 MPa.