NEGATIVE-ELECTRODE ACTIVE MATERIAL FOR NON-AQUEOUS ELECTROLYTE SECONDARY BATTERY, NEGATIVE ELECTRODE FOR NON-AQUEOUS ELECTROLYTE SECONDARY BATTERY, AND NON-AQUEOUS ELECTROLYTE SECONDARY BATTERY (as amended)

摘要

A non-aqueous electrolyte secondary battery that contains a silicon material as a negative-electrode active material has improved cycle life. A negative-electrode active material particle (10) according to an embodiment includes a lithium silicate phase (11) represented by Li_2zSiO_(2+z) (0z2), silicon particles (12) dispersed in the lithium silicate phase (11), and a metallic compound (15) (other than lithium compounds and silicon oxides) dispersed in the lithium silicate phase (11). The metallic compound (15) is preferably selected from zirconium oxide, aluminum oxide, zirconium carbide, tungsten carbide, and silicon carbide.