| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a negative electrode active material for a secondary battery, high in capacity and excellent in cycle characteristics.SOLUTION: A negative electrode active material for a nonaqueous electrolyte secondary battery is used. In the negative electrode active material, a first phase having lithium storage properties is dispersed in a second phase as a matrix, and a third phase having a composition different from those of the first phase and the second phase and having a Vickers hardness of 6.86 GPa or less exists between the first phase and the second phase. The third phase is preferably one or more single substances selected from the groups consisting of a first group consisting of Al, Ag and Zn, a second group consisting of Ga, In, Sn, Pb and Bi, and a third group consisting of Fe, Ni, Cu, Ti, Co, Cr, Zr and V, or a compound of an element selected from the group consisting of the first group and the second group and an element selected from the third group.</p> |
