Abstract: A negative electrode active material for a lithium ion secondary battery includes silicon oxide particles, each of which has carbon on at least a portion of its surface, in which: a ratio (PSi/PSiO2) of an intensity of an X-ray diffraction peak at 2? of from 27° to 29°, which is derived from Si, to an intensity of an X-ray diffraction peak at 2? of from 20° to 25°, which is derived from SiO2, is within a range of from 1.0 to 2.6, when CuK? radiation having a wavelength of 0.15406 nm is used as a radiation source; and a ratio (SH2O/SN2) of a specific surface area calculated from moisture adsorption at 298 K to a specific surface area calculated from nitrogen adsorption at 77 K is 0.60 or less.

Abstract: A negative electrode active material for a lithium ion secondary battery includes silicon oxide particles, each of which has carbon on at least a portion of its surface, in which: a ratio (PSi/PSiO2) of an intensity of an X-ray diffraction peak at 2? of from 27° to 29°, which is derived from Si, to an intensity of an X-ray diffraction peak at 2? of from 20° to 25°, which is derived from SiO2, is within a range of from 1.0 to 2.6, when CuK? radiation having a wavelength of 0.15406 nm is used as a radiation source; and a specific surface area calculated from carbon dioxide adsorption at 273 K is 8.5 m2/g or less.

Abstract: A negative electrode active material for a lithium ion secondary battery, the negative electrode active material includes silicon oxide particles, each of which has carbon on at least a portion of its surface, in which: a ratio (PSi/PSiO2) of an intensity of an X-ray diffraction peak at 2? of from 27° to 29°, which is derived from Si, to an intensity of an X-ray diffraction peak at 2? of from 20° to 25°, which is derived from SiO2, is within a range of from 1.0 to 2.6, when CuK? radiation having a wavelength of 0.15406 nm is used as a radiation source; and a specific surface area calculated from moisture adsorption at 298 K is 6.5 m2/g or less.

Abstract: A negative electrode active material for a lithium ion secondary battery is one that includes silicon oxide particles each having carbon present on a part of a surface of or an entire surface thereof, that has a ratio (PSi/PSiO2) of an intensity of an X-ray diffraction peak at 2? of from 27° to 29°, that is derived from Si, to an intensity of an X-ray diffraction peak at 2? of from 20° to 25°, that is derived from SiO2, of from 1.0 to 2.6 when CuK? radiation with a wavelength of 0.154056 nm is employed as a radiation source, and that has a mean value of an aspect ratio (S/L) of its minor axis (S) to its major axis (L) of 0.45?S/L?1.

Abstract: A negative electrode active material for a lithium ion secondary battery includes silicon oxide particles, each of which has carbon on at least a portion of its surface, in which: a ratio (PSi/PSiO2) of an intensity of an X-ray diffraction peak at 2? of from 27° to 29°, which is derived from Si, to an intensity of an X-ray diffraction peak at 2? of from 20° to 25°, which is derived from SiO2, is within a range of from 1.0 to 2.6, when CuK? radiation having a wavelength of 0.15406 nm is used as a radiation source; and a ratio (SH2O/SN2) of a specific surface area calculated from moisture adsorption at 298 K to a specific surface area calculated from nitrogen adsorption at 77 K is 0.60 or less.

Abstract: A negative electrode active material for a lithium ion secondary battery includes silicon oxide particles, each of which has carbon on at least a portion of its surface, in which: a ratio (PSi/PSiO2) of an intensity of an X-ray diffraction peak at 2? of from 27° to 29°, which is derived from Si, to an intensity of an X-ray diffraction peak at 2? of from 20° to 25°, which is derived from SiO2, is within a range of from 1.0 to 2.6, when CuK? radiation having a wavelength of 0.15406 nm is used as a radiation source; and a specific surface area calculated from carbon dioxide adsorption at 273 K is 8.5 m2/g or less.

Abstract: A negative electrode active material for a lithium ion secondary battery, the negative electrode active material includes silicon oxide particles, each of which has carbon on at least a portion of its surface, in which: a ratio (PSi/PSiO2) of an intensity of an X-ray diffraction peak at 2? of from 27° to 29°, which is derived from Si, to an intensity of an X-ray diffraction peak at 2? of from 20° to 25°, which is derived from SiO2, is within a range of from 1.0 to 2.6, when CuK? radiation having a wavelength of 0.15406 nm is used as a radiation source; and a specific surface area calculated from moisture adsorption at 298 K is 6.5 m2/g or less.