Solid electrolyte composition, method for producing solid electrolyte composition, and method for producing solid electrolyte member

A solid electrolyte composition comprising:

• a solid electrolyte material having ion-binding properties;
• and
• an organic solvent, wherein:
• the organic solvent includes a first organic solvent and a second organic solvent,
• the first organic solvent is a halogen-group-containing compound,
• the second organic solvent is at least one selected from the group consisting of an ether-group-containing compound and a hydrocarbon, and
• the solid electrolyte material includes a material represented by a compositional formula LiaMebYcX6, where X is at least one selected from the group consisting of Cl, Br, and I, m is the valence of Me, a+mb+3c=6, b>0, c>0, and Me is at least one selected from the group consisting of metalloid elements and metal elements other than Li and Y.