Carbon coating of Li4Ti5O12 using amphiphilic carbonaceous material for improvement of lithium-ion battery performance

Carbon coating of fine particles of Li4Ti5O12 synthesized under hydrothermal condition is carried out by amphiphilic carbonaceous material (ACM) in aqueous solution, followed by carbonization at 800 degrees C for 2 h. The particles prepared are comprised of highly-crystalline spinel-type Li4Ti5O12 with the size in the range of 100-400 nm without any agglomeration, of which surface is uniformly covered by a thin carbon layer. Their electrochemical performance as an anode in lithium-ion batteries is evaluated. The initial discharge capacity of carbon-coated Li4Ti5O12 at 20 C rate is 137 mA h g(-1) and remains as high as 125 mA h g(-1) after 100 cycles (91% retention), exhibiting good rate and cyclic performance. Carbon coating by using ACM as carbon precursor gives the Li4Ti5O12 particles an enhanced performance as an anode in lithium-ion batteries, owing to the improvement in electrical conductivity, polarization and ability of dispersion. This non-organic coating process may present a new economic, facile, and green pathway for the preparation of carbon-coated Li4Ti5O12 as a high power anode material in lithium-ion batteries. (C) 2012 Elsevier B.V. All rights reserved.