Composite particles, negative electrode material, and lithium-ion secondary battery

Abstract

An object of the present invention is to provide composite particles capable of suppressing oxidation over time of a Si—C composite material. Composite particles (B) of the present invention contains composite particles (A) containing carbon and silicon; and amorphous layers coating surfaces thereof, where the composite particles (B) have ISi/IG of 0.10 or more and 0.65 or less, and have R value (ID/IG) of 1.00 or more and 1.30 or less, when a peak due to silicon is present at 450 to 495 cm−1, an intensity of the peak is defined as ISi, an intensity of a G band (peak intensity in the vicinity of 1600 cm−1) is defined as IG, and an intensity of a D band (peak intensity in the vicinity of 1360 cm−1) is defined as ID in a Raman spectrum, and where the composite particles (B) have a full width at half maximum of a peak of a 111 plane of Si of 3.0 deg. or more using a Cu-Kα ray in an XRD pattern.

Dependencies are inferred from the claim text.