The invention discloses a long-life modified
natural graphite cathode material as well as a preparation method and use thereof. According to the preparation method,
natural graphite powder and asphaltare dipped by virtue of a hot isostatic pressure
machine, so that holes in
graphite particles can be completely filled with
asphalt at high temperature and
high pressure conditions; and meanwhile, anasphalt
coating layer is formed on the surface of the
natural graphite powder, and graphitization is carried out so as to obtain the modified natural
graphite cathode material with a core-shell structure, wherein synthetic
graphite is embedded into the inside and surface of the natural graphite in situ, the
filling rate of the synthetic graphite in the holes of the natural graphite is more than or equal to 94%, the surfaces of the particles are smooth, and the spheroidization degrees of the particles are high. According to the preparation method, the primary coulombic efficiency of the modified natural graphite
cathode material is more than or equal to 96%, and the capacity
retention ratio of the material after being circulated at a
room temperature 1C for 1500 cycles is more than or equal to 80%, so that the
prepared material is high in primary coulombic efficiency, long in service life and can be used for replacing synthetic graphite for producing
powder battery cathode materials, and the cost is greatly lowered. The preparation method is simple in preparation process and low in cost and has relatively high practicability.