Anode composite material of lithium ion battery and preparation method thereof

The invention provides an anode composite material of a lithium ion battery and a preparation method thereof. The anode composite material of the lithium ion battery has a molecular formula of Li2FeSio4/C. According to mass percentage, the content of silicate is 95%-80%, and the content of compounded carbon is 5%-20%. The preparation method of the anode composite material comprises the following steps: (1) ferrite and the silicate are evenly mixed by a ball mill according to a stoichiometric proportion, thereby obtaining a mixture; the mixture is fully washed with deionized water and then dried, thereby obtaining a precursor; and (2) the precursor, lithium salt and organic carbon source undergo mixing, ball milling, tabletting and microwave treatment under inert gas shielding, thereby obtaining the Li2FeSio4/C anode composite material of the lithium ion battery. The invention can obtain the carbon-coated anode composite material which has good crystals, thin and uniform crystal grains and high purity and improve the electrochemical properties of a Li2FeSio4/C anode material.