NEGATIVE ELECTRODE ACTIVE SUBSTANCE FOR NON-AQUEOUS SECONDARY CELL AND METHOD FOR PRODUCING THE SAME

[Assignment] Providing a noble negative-electrode active material including silicon, and a production process for the same. [Solving Means] A negative-electrode active material for non-aqueous-system secondary battery including a silicon phase and a composite oxide phase (a CaSiO 3 phase, for instance) is obtained by mixing a silicon oxide (SiO, for instance) with a silicon compound (CaSi 2 , for instance), which includes silicon and at least one member of elements being selected from the group consisting of Group 2 (or Group 2A) elements in the Periodic Table, to prepare a mixed raw material, and then reacting the mixed raw material. The composite oxide phase demonstrates the advantage of inhibiting electrolytic solutions from decomposing in a smaller amount than does the conventional SiO 2 phase.