Negative electrode active material, negative electrode sheet, secondary battery, and electronic device

Abstract

A negative electrode active material, a negative electrode sheet, a secondary battery, and an electronic device. The negative electrode active material includes graphite particles and a silicon carbide layer disposed on a surface of the graphite particles, where a mass percentage Y % of silicon in the negative electrode active material and an average height Lc nm of the negative electrode active material along a c-axis direction satisfy: 0.3×(32−Lc)≤Y≤0.9×(32−Lc). In negative electrode active particles, disposing a silicon carbide layer on the surface of the graphite particles and controlling a thickness of the silicon carbide layer in the negative electrode active material based on the average height of the graphite particles along the c-axis direction can effectively reduce reactions between the graphite particles and an electrolyte, reducing consumption of active ions, and improving the initial coulombic efficiency of the battery.

Dependencies are inferred from the claim text.