The present application relates to a metal oxide and synthesis of a lithium ion battery. Specifically, the present application selects a cobalt oxide compound, which uses Co3O4 as a main body, as a precursor of lithium cobalt oxide, and anion doping is performed in particles of Co3O4 to obtain a doped precursor for lithium cobalt oxide. The general formula of the precursor can be expressed as Co3(O1-yMy)4, where about 0