| abstract |
The present invention relates to a negative electrode active material for a lithium secondary battery and a secondary battery using same, and more specifically provides a negative electrode active material for a lithium secondary battery and a secondary battery using same wherein the active material comprises an alloy represented by chemical formula (1) Si x Ni y M z (in the formula 50≤x≤90, 1≤y≤49, 1≤z≤49, x+y+z=100, x, y and z are each atomic percentages, and M is a transition metal), and the amorphization degree of a micro crystal region on the matrix in the alloy is at least 30%. |