Negative electrode material for secondary battery having lithium-doped silicon-silicon oxide composite, method for manufacturing negative electrode, and lithium secondary battery

摘要

The present invention is a negative electrode material for a secondary battery with a non-aqueous electrolyte comprising at least a silicon-silicon oxide composite and a carbon coating formed on a surface of the silicon-silicon oxide composite, wherein at least the silicon-silicon oxide composite is doped with lithium, and a ratio I(SiC)/I(Si) of a peak intensity I(SiC) attributable to SiC of 2θ=35.8±0.2° to a peak intensity I(Si) attributable to Si of 2θ=28.4±0.2° satisfies a relation of I(SiC)/I(Si)≦0.03, when x-ray diffraction using Cu-Kα ray. As a result, there is provided a negative electrode material for a secondary battery with a non-aqueous electrolyte that is superior in first efficiency and cycle durability to a conventional negative electrode material.