Negative electrode active material for lithium ion secondary battery, negative electrode for lithium ion secondary battery, and lithium ion secondary battery

The negative electrode active material for a lithium ion secondary battery includes silicon oxide particles on which carbon is present on a portion or the entirety of the surface of the particles. When CuK[alpha] radiation having a wavelength of 0.15406 nm is used as a radiation source, the ratio (PS i/PS iO 2)of SiO2-derived X-ray diffraction peak intensity at 2[theta] = 20 to 25 degrees to Si-derived X-ray diffraction peak intensity at 2[theta] = 27 to 2 degrees is within a range of 1.0 to 2.6, and the specific surface area calculated from water vapor adsorption at 298K is 6.5m2/g or less. 一种锂离子二次电池用负极活性物质，其包含在表面的一部分或全部中存在碳的硅氧化物粒子，使用波长0.15406nm的CuKα射线作为射线源时，源自Si的2θ＝27°～29°的X射线衍射峰强度相对于源自SiO的2θ＝20°～25°的X射线衍射峰强度之比(P/P)为1.0～2.6的范围，由298K时的水蒸气吸附算出的比表面积小于或等于6.5m/g。