Preparation method of an anode material for lithium-ion batteries

A preparation method of an anode material for lithium-ion batteries, comprising following steps:

• (1) Dispersing tetrabutyl titanate in glycerol solvent to prepare 1˜5 wt % solution and adding hexadecyl trimethyl ammonium bromide solution with the concentration of 12 g/L, adding tetramethylammonium hydroxide to adjust PH to be 9-10, mixing uniformly;
• then adding 1 wt % ammonium fluoride solution, mixing uniformly and then transferring to a hydrothermal reactor, heating at 150-200° C. for 1˜6 h, the product was centrifuged, and washed with ethanol and water for 10 times, and dried in a vacuum drying oven at 60° C. for 12 h to obtain titanium/nitrogen/fluorine-doped porous titanium dioxide;
• Wherein:
• the mass ratio of tetrabutyl titanate:hexadecyl trimethyl ammonium bromide:tetramethylammonium hydroxide:ammonium fluoride is 1:20˜40:0.1˜1:0.5˜2;
• (2) Preparing 1˜10 wt % mass concentration of titanium/nitrogen/fluorine-doped porous titanium dioxide organic solution, and then adding 1˜10 wt % mass concentration of lithium salt solution, mixing uniformly, then adding graphite, mixing uniformly, and spray drying to obtain porous lithium titanate-coated graphite composites;
• wherein:
• the mass ratio of titanium/nitrogen/fluorine-doped porous titanium dioxide:lithium salt:graphite is 1˜10:1˜10:100;
• (3) Weighing porous lithium titanate-coated graphite composites and ammonium fluoride in a mass ratio of 100:1˜10, placing them in a tube furnace, wherein the ammonium fluoride is located in the upstream direction of the gas flow, and heated at 400° C. for 2 h under the protection of argon, then heated to 800° C. for carbonization for 6 h to obtain nitrogen-fluorine co-doped lithium titanate/graphite composites.