Negative electrode material for secondary battery with non-aqueous electrolyte, method for manufacturing negative electrode material for secondary battery with non-aqueous electrolyte, and lithium ion secondary battery

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 2¸=35. 8±0.2° to a peak intensity I(Si) attributable to Si of 2¸=28.4±0.2° satisfies a relation of I(SiC)/I(Si)¤0.03, when x-ray diffraction using Cu-K± 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.