Patent ID: 8399131

Claim:
A composite negative electrode active material comprising: a graphitizable carbon material (A) containing a layered structure formed of stacked carbon layers partially having a three-dimensional regularity; and a carbon material (B), wherein: a ratio I(101)/I(100) of the graphitizable carbon material (A) satisfies 0.5<1(101)/I(100)<1.0, the carbon material (B) is capable of absorbing and desorbing lithium via an interlayer intercalation reaction, and a ratio I(101)/I(100) of the carbon material (B) is not less than 0 and lower than the ratio I(101)/I(100) of the graphitizable carbon material (A), the ratio I(101)/I(100) is a ratio of a peak intensity (101) attributed to a (101) plane at 2θ=about 44° to a peak intensity I(100) attributed to a (100) plane at 2θ=about 42° in a wide-angle X-ray diffraction pattern measured with CuKα radiation, and a surface of the graphitizable carbon material (A) is coated with the carbon material (B), or at least part of the graphitizable carbon material (A) and at least part of the carbon material (B) are fused together.