Abstract: A main object of the present disclosure is to provide a liquid electrolyte in which concentration of active fluoride ion is high. The present disclosure achieves the object by providing a liquid electrolyte to be used in a fluoride ion battery, the liquid electrolyte comprising: a potassium fluoride; an alkali metal amide salt including a cation of an alkali metal and an amide anion; and a glyme represented by a general formula R1—O(CH2CH2O)n—R2, in which R1 and R2 is each independently an alkyl group including 4 or less carbon atoms or a fluoroalkyl group including 4 or less carbon atoms, and n is within a range of 2 to 10.

Abstract: A main object of the present disclosure is to provide a liquid electrolyte in which concentration of active fluoride ion is high. The present disclosure achieves the object by providing a liquid electrolyte to be used in a fluoride ion battery, the liquid electrolyte comprising: a potassium fluoride; an alkali metal amide salt including a cation of an alkali metal and an amide anion; and a glyme represented by a general formula R1—O(CH2CH2O)n—R2, in which R1 and R2 is each independently an alkyl group including 4 or less carbon atoms or a fluoroalkyl group including 4 or less carbon atoms, and n is within a range of 2 to 10.

Abstract: A main object of the present disclosure is to provide a liquid electrolyte in which concentration of active fluoride ion is high even when a cesium fluoride (CsF) is included therein. The present disclosure achieves the object by providing a liquid electrolyte to be used in a fluoride ion battery, the liquid electrolyte comprising: a cesium fluoride and a solvent; and an amount of moisture is 50 ppm or more and 1100 ppm or less.