A novel carbon-coated LiCoO2 as cathode material for lithium ion battery

Using a commercially available LiCoO2 as starting material, a surface-modified cathode material was obtained by coating it with a nano layer of amorphous carbon. The carbon-coated LiCoO2 was characterized by X-ray diffraction analysis, scanning electronic microscopy, transmission electronic microscopy, electrochemical impedance spectroscopy and measurement of charge/discharge behavior. Results show that the carbon-coated LiCoO2 displays marked lower charge transfer resistance, higher lithium ion diffusion coefficient and much better rate capability than the original LiCoO2. It also indicates promising application of lithium ion batteries in the areas requiring charge and discharge at high rate. (c) 2007 Elsevier B.V. All rights reserved.