POSITIVE ELECTRODE MATERIAL FOR HIGH-POWER LITHIUM ION BATTERY AND PREPARATION METHOD THEREOF

Disclosed is a positive electrode material for a high-power lithium ion battery. The positive electrode material is in form of secondary particles with a hollow microsphere structure, and a shell of the secondary particles is formed by aggregating a plurality of primary particles. The secondary particles have a uniform particle size, a loose and porous surface, and a large specific surface area. The obtained particles are regular in shape, stable in material structure, so that the positive electrode material has high rate performance and excellent cycle performance. The disclosure also provides a preparation method for the positive electrode material comprising (1) synthesizing a NiCoM(OH)precursor by a co-precipitation method, such that the precursor has a central portion consisted by fine particles and a shell portion consisted by large particles having a larger particle size than that of the fine particles; (2) mixing the precursor and a lithium salt uniformly, and adding an oxide of a doping element during the mixing, and then sintering the mixture to provide a LiNiCoMOpositive electrode material. The preparation method is simple and low cost, and can be industrialized.