Preparation method of carbon-coated lithium titanate composite material for lithium ion power battery

The invention discloses a preparation method of a carbon-coated lithium titanate composite material for a lithium ion power battery. The method comprises the following steps of: dissolving an amphiphilic carbon material into water at room temperature to prepare suspension, adding lithium titanate and mixing uniformly; heating to 80-90 DEG C, evaporating to dryness, and drying; performing constant-temperature thermal treatment for 0.5-10 hours at 500-1,000 DEG C to obtain the lithium titanate with a particle size of 100-400nm serving as a kernel; and coating the kernel with an amphiphilic carbon material with thickness of 3nm. The preparation method disclosed by the invention is environment-friendly, has a simple preparation process and is easy to realize large-scale production. The prepared material has large charge/discharge capacity, excellent heavy-current charge/discharge performance and stable cycle performance when used as a lithium ion battery cathode material, wherein the 10C discharge/charge capacity is 160mAh/g, the 20C discharge/charge capacity reaches 143mAh/g, and the capacity retention rate reaches 91% after 100 times of heavy-current 20C discharge and charge.