Patent ID: 9466855
Filing Date: 2016-10-11
CPC Classification: H01M,Y02E

Claim Text:
1. A sodium ion secondary battery, comprising: a non-aqueous electrolytic solution that includes an additive for a sodium ion secondary battery comprising fluoroethylene carbonate, and one of a non-aqueous solvent containing a saturated cyclic carbonate and a non-aqueous solvent containing a saturated cyclic carbonate and a chain carbonate; a positive electrode that includes a positive-electrode active material capable of storing and releasing a sodium; and a negative electrode that includes a coating formed on a surface of the negative electrode, the coating containing a composite material containing carbon, oxygen, fluorine and sodium, and that includes a negative-electrode active material containing a hard carbon, wherein a content of the additive for a sodium ion secondary battery in the non-aqueous electrolytic solution is in a range from 0.5% by volume to 10% by volume inclusive.