METHOD FOR PRODUCING SOLID ELECTROLYTE, SOLID ELECTROLYTE, POSITIVE ELECTRODE MATERIAL, AND BATTERY

A production method for a solid electrolyte of the present disclosure includes (A) performing fluorination treatment on a raw material including a composite oxide containing Li and Ti, to obtain a solid electrolyte including a crystal phase represented by a composition formula (1): LiTiF. A solid electrolyte of the present disclosure includes a crystal phase represented by the composition formula (1): LiTiFand is substantially free of TiF.