Synthesis by TEA sol-gel method and electrochemical properties of Li4Ti5O12 anode material for lithium-ion battery

Anode material Li4Ti5O12 for lithium-ion batteries have been synthesized by a novel sol-gel method with triethanolamine(TEA) as a chelating agent and LiAc*2H2O and Tetrabutyl titanate [Ti (OC4H9) 4] as starting materials. Various initial conditions were studied in order to find the optimal conditions for the synthesis of Li4Ti5O12. The as-prepared samples have been characterized by means of XRD, IR and SEM. Its electrochemical behavior was evaluated in a liquid electrolyte in lithium-ion batteries. These analyses indicated that the prepared Li-Ti-O powders belonged to a spinel structure and had a uniform morphology with average particle size from 223 to 105 nm with the increase in TEA content. At 1.55 V (vs. Li), the Li4Ti5O12 electrode with the ratio of TEA to Ti ions 0.8 exhibited an initial discharge capacity of 168 mA h/g and a subsequent charge capacity of 151 mA h/g. The results of cyclic voltammetry for Li4Ti5O12 showed that at the potential range from 1.5 to 1.7 V (vs. Li), there was a pair of reversible redox peaks correspond to the process of Li+ intercalation and de-intercalation in the spinel Li-Ti-O oxides.