NEGATIVE ELECTRODE ACTIVE MATERIAL FOR LITHIUM SECONDARY BATTERY, AND LITHIUM SECONDARY BATTERY

PROBLEM TO BE SOLVED: To provide a negative electrode active material for a lithium secondary battery which can improve cycle characteristics and is excellent in productivity. SOLUTION: The negative electrode active material has many Si nuclei and an alloy matrix surrounding the surroundings of the Si nuclei. The alloy to constitute the alloy matrix contains an element (x) of one kind or two kinds or more selected from Al, Sn, Ag, Bi, and Zn and an element (y) of one kind or two kinds or more selected from Co, Ni, Ag, Al, Fe, Zr, Cr, Cu, P, V, Mn, Nb, Mo, In, and a rare earth element and different from the above element (x). The alloy to constitute the above alloy matrix preferably contains an element of one kind or two kinds or more selected from Ag, Al, Bi, P, Sn, Ti, and Zn as an element (z) different from the above element (x) and the element (y). COPYRIGHT: (C)2009,JPO&INPIT