Patent ID: 10236531

Abstract:
This invention provides a powder for a negative electrode of a lithium ion secondary battery, which is a powder that includes a silicon oxide powder containing Li. When a molar ratio between Li, Si and O is taken as y:1:x, the average composition of the powder overall satisfies the relation 0.5<x<1.5 and the relation 0.1<y/x<0.8. The volume median diameter of the powder for a negative electrode is within a range from 0.5 to 30 μm. When X-ray diffraction measurement of the powder is performed using a Cu Kα ray, a relation P2/P1≤1.0 and a relation P3/P1≤1.0 are satisfied, where P1 represents a height of a peak attributed to Li2SiO3, P2 represents a height of a peak attributed to crystalline Si, and P3 represents a height of a peak attributed to Li4SiO4.