▎ 摘　　要

NOVELTY - Preparing hard carbon cathode material comprises passivating hard carbon precursor to obtain the material, where the hard carbon precursor comprises a modified hard carbon precursor, the modified hard carbon precursor comprises pre-lithiated hard carbon precursor and/or pre-sodium hard carbon precursor, and the passivating treatment comprises reacting sodium and/or lithium in hard carbon precursor with passivating substance under the protective atmosphere to form a passivating layer, and reducing the activity of sodium and/or lithium in the hard carbon precursor. USE - The method is useful for preparing hard carbon cathode material. ADVANTAGE - The method: improves stability and safety of the pre-lithium or pre-sodium precursor in the air, and processing performance of pre-lithium or pre-sodium hard carbon cathode material when used as a secondary battery cathode material, slurry stability of cathode sheet during preparation process, and first-time efficiency of material; and is excellent for hard carbon cathode material and excellent cycle performance in the battery system. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: a hard carbon cathode material prepared by the above-mentioned method; a mixed cathode material; and a secondary battery.