TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Material: The microcrystalline grain has a diameter of 38-41 nm and the lithium titanate has an average particle diameter of 1.2-1.8 mu m. The composite material further comprises carbon, the content of the lithium titanate is 85-99 (preferably 92-97) wt.% and the content of the carbon is l-15 (preferably 3-8) wt.%. Preferred Components: The negative electrode further includes an adhesive and a conducting additive. The non-aqueous electrolyte includes LiPF6. The non-aqueous electrolyte includes at least one organic solvent selected from ethylene carbonate, propylene carbonate, di-ethyl carbonate and di-methyl carbonate. Preferred method: The method further involves mixing the carbon source with a mixture of the titanate oxide particles, the soluble lithium source and the water before removing water. The carbon source is used at such a dosage that the carbon amounts to l-15 wt.% of the total weight of the composite material; the carbon source is water soluble and/or non-soluble composition; the water soluble composition is selected from carbohydrate, cellulose-based polymer and polyvinyl alcohol, the water non-soluble composition comprises selected from benzene-naphthalene-phenanthrene terpolymer, benzene-naphthalene biopolymer, benzene-anthracene biopolymer, phenolic resin, furfural resin, artificial graphite, nature graphite, superconducting acetylene black, acetylene black, carbon black and carbonaceous mesophase sphere, and the D95 of the water non-soluble composition particle is less than l mu m. The sintering temperature is 700-1000 degrees C and the sintering time is 5-48 hours. The inert gas is selected from carbon oxide, carbon dioxide, N2 and zero group element in the periodic table of the elements. The D50 of the titanium dioxide particles is 0.1-0.3 mu m and D95 is 0.6-0.9 mu m. The molar ratio of the soluble lithium source to the titanium dioxide is 0.95-1.1:1.25, and a weight ratio of the soluble source to the water is 1:1-15. The soluble lithium source is selected from lithium hydroxide, lithium acetate, lithium oxalate and lithium nitrate. EXAMPLE - Lithium hydroxide-hydrate (LiOH-H2O) was dissolved into deionized water (180 g) and glucose (9.7 g) was added into solution thus formed. After the glucose was completely dissolved, anatase-type ultrafine titanium dioxide having D50 of 0.7 mu m and D95 of 0.7 mu m with weight of 47.9 g was added into the solution under the condition of stirring. The solution was stirred for another 30 minutes and dried under 120 degrees C, and a precursor was obtained after removing water. The precursor was sintered for 20 hours under a temperature of 800 degrees C in nitrogen atmosphere and naturally cooled to room temperature to obtain lithium titanate composite material.