Lithium-rich layered oxide material with phase structure gradient and its preparation method

Abstract

A lithium-rich layered oxide material with a phase structure gradient and method for making the same are disclosed, used as cathode material for lithium ion battery. The invention has the following technical features: the spherical granule-shaped lithium-rich layered oxide material contains two types of structural units whose ratio gradually changes from the center to the surface of the spherical granule, wherein the monoclinic LiMnOstructural unit is gradually reduced, and the rhombohedral LiTMOstructural unit is gradually increased from the center to the surface of the spherical granule. By controlling the ratio of the monoclinic LiMnOstructural unit versus the rhombohedral LiTMOstructural unit along from the center to the surface the spherical granule, the performance of the Lithium-rich layered oxide materials as cathode for lithium ion battery, such as cyclic stability, specific discharge capacity, safety and other properties, is improved. The preparation process is simple and easy to control, the cost of raw materials is low and the environment is friendly. It can be industrialized on a large scale and has a good prospect of application.