TERNARY POSITIVE ELECTRODE MATERIAL, PREPARATION METHOD THEREFOR, AND SECONDARY BATTERY

The present disclosure relates to the technical field of batteries, and in particular to a ternary cathode material and a preparation method thereof and a secondary battery. The above ternary cathode material includes a bulk, a first coating layer provided on a surface of the bulk, and a second coating layer provided on a surface of the first coating layer. The bulk includes a lithium-nickel-cobalt-manganese oxide, and the bulk is doped with an M1 element, wherein the M1 element includes Mo, Hf, and La. The first coating layer includes CeO2 and a La-containing compound, and the CeO2 and the La-containing compound are each independently distributed in a granular form on the surface of the bulk. The second coating layer includes an oxide containing an M2 element, and the M2 element is at least one selected from B and Al. The above ternary cathode material has relatively high specific capacity and cycle performance. In addition, the present disclosure further provides a secondary battery and an electric device including the above ternary cathode material. The above secondary battery has both a relatively high energy density and relatively high cycle performance.