NEGATIVE-ELECTRODE ACTIVE MATERIAL FOR NON-AQUEOUS ELECTROLYTE SECONDARY BATTERY AND NON-AQUEOUS ELECTROLYTE SECONDARY BATTERY

A non-aqueous electrolyte secondary battery that contains a silicon material as a negative-electrode active material has improved initial charge/discharge efficiency. A negative-electrode active material particle () according to an embodiment contains a base particle (), which includes a lithium silicate phase () represented by LiSiO{0