Nonaqueous electrolyte secondary battery

摘要

The invention provides a nonaqueous electrolyte secondary battery which employs, as a negative electrode active material, a carbide containing an alkali metal in a charged stage. The carbide used is an ionic bond type carbide, a covalent bond type carbide, or an intermetallic compound type carbide. The ionic bond type carbide is exemplified as Al4C3, Al2C6, Na2C2, K2C2, Cu2C2, Ag2C2, MgC2, Mg2C3, CaC2, ZnC2, VC2 and the like. The covalent bond type carbide is exemplified as SiC, B12C3, Cr3C2, Cr7C3, Cr4C, and the like. The intermetallic compound type carbide is exemplified as TiC, VC, V4C3, V5C, MoC, Mo2C, WC, W2C, Mn3C, Mn23C6, Mn7C3, Fe3C, Fe2C, FeC, Co3C, Co2C, CoC2, Ni3C and the like. A highly reliable nonaqueous electrolyte secondary battery with a high energy density and excellent cycle life characteristics can be obtained.