NEGATIVE ELECTRODE ACTIVE MATERIAL, MIXED NEGATIVE ELECTRODE ACTIVE MATERIAL, NEGATIVE ELECTRODE FOR NONAQUEOUS ELECTROLYTE SECONDARY BATTERY, LITHIUM ION SECONDARY BATTERY, AND METHOD FOR PRODUCING NEGATIVE ELECTRODE ACTIVE MATERIAL

A negative electrode active material includes: particles of negative electrode active material, the particles of negative electrode active material contain particles of silicon compound containing a silicon compound (SiO:0.5≤x≤1.6); the particles of silicon compound contain at least one kind or more of LiSiOand LiSiO; the particles of negative electrode active material contain LiCOand LiOH on a surface thereof; and a content of the LiCOis 0.01% by mass or more and 5.00% by mass or less relative to a mass of the particles of negative electrode active material and a content of the LiOH is 0.01% by mass or more and 5.00% by mass or less relative to the mass of the particles of negative electrode active material. Thus a negative electrode active material is capable of improving initial charge/discharge characteristics and the cycle characteristics when used as a negative electrode active material of the secondary battery.