Negative electrode active material and preparation method thereof, secondary battery, and electronic device

Abstract

A hard carbon material contains micropores and ultramicropores, a pore diameter of the micropores is less than 2 nm, a pore diameter of the ultramicropores is less than 0.7 nm, a pore volume of the micropores accounts for 95% to 100% of a total pore volume, a pore volume of the ultramicropores ranges from 0.01 cm3/g to 0.2 cm3/g, and the pore volume of the ultramicropores accounts for 80% to 99% of the total pore volume. The negative electrode active material provided in this application exhibits a stable low-potential plateau, high specific capacity, and high reversible capacity, and applying the negative electrode active material of this application to secondary batteries enhances the energy density of secondary batteries while improving their cycle performance.

Dependencies are inferred from the claim text.