Patent ID: 8361656

Claim:
A composite anode active material, comprising: a metal, M″, capable of alloy formation with lithium; an intermetallic compound which forms at least one intermediate phase, and each of the at least one intermediate phase comprises a compound represented by M x M′ y where 0<x<1, 0<y<1, and x+y=1; M′ is Al, and M is selected from Ni, Ti, Co, V, and Mo; and a solid solution which is an alloy of the metal, M″, capable of alloy formation with lithium and the intermetallic compound, the solid solution having a same crystal structure as the intermetallic compound, and the solid solution being represented by M x M′ y-z M″ z where 0<x<1, 0<y<1, 0<z<y, and x+y=1; and M″ is selected from Sc, Y, Lu, Mn, Re, Fe, Ru, Os, Cu, Ag, Au, Zn, Cd, Hg, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Th, Pa, U, Zr, Hf, Nb, Ta, Cr, W, Rh, Ir, Pd, Pt, Ga, In, Tl, Si, Ge, Pb, Mg, Sb, and Bi, and the composition of the solid solution is different from the composition of the intermetallic compound.