Surface coated lithium cobaltate, preparation method thereof and lithium ion battery

The invention discloses surface coated lithium cobaltate and a preparation method thereof. Li2O and B2O3 are coated on the surface of the lithium cobaltate, and the coating quantity is Li2O:LiC0O2 of (0.008-0.012):1 and B2O3:Li2O of (1.8-2.2):1 according to a mol ratio. The invention also discloses a lithium ion battery containing the lithium cobaltate as an anode material. Compared with the capacity of a traditional battery system, the energy density of the lithium ion battery disclosed by the invention is increased by nearly 10%; and the lithium ion battery has the advantages of excellent circulating property and safety.