Patent ID: 10818920

Abstract:
A negative electrode active material having high cycle durability contains an alloy represented by the following chemical formula (1): SixSnyMzAa  (1) wherein M is Zn, A is unavoidable impurities, x, y, z, and a represent % by mass values, and in that case, 0<x<100, 0<y<100, 0<z<100, 0≤a<0.5, and x+y+z+a=100, in which the half width of the diffraction peak of the (111) surface of Si in the range of 2θ=24 to 33° by X ray diffraction measurement of the alloy using CuKα ray is 0.7° or more, and the x is more than 23 and less than 64, the y is 4 or more and less than 34, and the z is more than 0 and less than 65.