Preparation method of core-shell structure and coated lithium cobalt oxide positive electrode material

The invention belongs to the field of lithium ion battery materials, and particularly relates to a cobalt carbonate composite precursor with a core-shell structure and a preparation method and application of a sintered lithium cobalt oxide coating. The method is realized through the following steps: 1) preparing and synthesizing a solution; 2) primary sintering; 3) secondary sintering; (4) ball milling; and 5) sintering for the third time to obtain the lithium cobalt oxide coated with the CNTs and is of the core-shell structure. The preparation method has the advantages that 1, in the ball milling process of the CNTs and the lithium cobalt oxide with the shell doped with the Al, the CNTs/Al composite powder is added, so that heat dissipation during charging and discharging of the battery is facilitated, polarization of the battery is reduced, the high and low temperature performance of the battery is improved, and the service life of the battery is prolonged; and 2, a large amount of aluminum segregation can