The present invention is high volume and the cycle life and provides a long lithium ion battery, the negative electrode material.
As constituent elements Si, Al, M1 (M1 is a Group 4 of the periodic table, a metal source hydrogen or more species selected from among transition metals, except for the group V), M2 (M2 is 1 is Group 4 of the periodic table, selected from the group V contains at least one metal source, hydrogen), are precipitated in the grain boundary of the Si-Al-M1-M2 alloy phase and the crystal grains constituting the fine crystal grains composed of alloy material having a Si showing a mesh-like structure.