ALKALI METAL-SULFUR SECONDARY BATTERY

摘要

PROBLEM TO BE SOLVED: To provide an alkali metal-sulfur secondary battery having a long life and the improved input/output density by inhibiting a side reaction during charge to improve the coulomb efficiency and inhibiting reduction in discharge capacity caused by repeated cycles of charge and discharge.SOLUTION: An alkali metal-sulfur secondary battery includes: a positive electrode 2 or a negative electrode having a sulfur-containing electrode active material; an electrolyte which contains an ether compound such as THF and glyme, and a solvent and in which a complex is formed of at least part of the ether compound and alkali metal salt; and a counter electrode 4. The solvent has hydrophobic effect in complete mixture with the complex and is one or more kinds selected from the group consisting of a fluorine-based solvent (excluding FCHC-O-CFCFH) not chemically reacting with alkali metal and alkali metal polysulfide (MS:1≤n≤8), ion fluid, and hydrocarbon.