Patent ID: 11387449

Abstract:
The negative electrode active material according to the present embodiment includes alloy particle containing an alloy component and oxygen of 0.50 to 3.00 mass %. The alloy component contains Sn: 13.0 to 40.0 at % and Si: 6.0 to 40.0 at %. The alloy particle contains: one or two phases selected from a D03 phase in which the Si content is from 0 to 5.0 at % and a δ phase in which the Si content is from 0 to 5.0 at %; one or two phases selected from an ε phase in which the Si content is from 0 to 5.0 at % and an η′ phase in which the Si content is from 0 to 5.0 at %; and an SiOx phase. The alloy particle has, in an X-ray diffraction profile, a peak having a largest integrated diffraction intensity in a range of 42.0 to 44.0 degrees of a diffraction angle 2θ.