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

The present invention improves at least one among the initial efficiency, the battery capacity, and the cycle characteristics of a non-aqueous electrolyte secondary battery. A negative electrode active material for a non-aqueous electrolyte secondary battery according to an embodiment of the present invention comprises porous composite particles containing silicon and silicon oxide (SiOx, 0 < x≤2), wherein some or all of the pores of the porous composite particles are filled with carbon, and some or all of the surfaces of the porous composite particles are coated with carbon.