Solid electrolyte material, battery using same, and method for producing solid electrolyte material

A method of manufacturing a solid electrolyte material, the method comprising

• firing a mixed material in an inert gas atmosphere, the mixed material including a halide including Li, a halide including Y, a halide including Sm, and a halide including DC, wherein
• the DC is at least one selected from the group consisting of Mg, Ca, Sr, and Ba,
• the solid electrolyte material is a solid electrolyte particle consisting of Li, DC, Y, Sm and X or made of a compound including Li, DC, Y, Sm and X as a main component,
• wherein
• the DC is at least one selected from the group consisting of Mg, Ca, Sr, Ba, and Zn,
• the X is at least one selected from the group consisting of Br and Cl,
• when the solid electrolyte particle is made of the compound including Li, DC, Y, Sm and X as a main component, a largest amount component of the particle in molar ratio is the compound,
• a median diameter of the solid electrolyte particles is 0.5 μm or more and 10 μm or less, and
• the solid electrolyte particle is represented by the following composition formula (1),
• Li3−2a−3dDCaY1−bSmb+dBr6−cClc (1)
• where the following four mathematical relations are satisfied:
• 0<a≤0.25;
• 0<b<1;
• 0≤c≤6;
• and
• 0≤d≤0.05.