Synthesis parameter dependence of the electrochemical performance of solvothermally synthesized Li4Ti5O12

Abstract

Pure Li4Ti5O12 with high crystallinity was successfully synthesized by a solvothermal process. The effects of initial Li/Ti ratio and post-heating temperature on the phase evolution, particle morphology and electrochemical properties were systematically investigated. Excess lithium, compared to the theoretical value in Li4Ti5O12, was required to get pure Li4Ti5O12 due to the condensation reaction. Low Li/Ti ratio led to the appearance of secondary phase rutile TiO2, while high heat-treatment temperature easily resulted in particle agglomeration of Li4Ti5O12 powder. The existence of rutile TiO2 decreased the specific capacity, and the particle agglomerate had a strong negative effect on the rate capability of electrode. The sample synthesized at the optimized condition exhibited a stable specific capacity of 150 mAh/g and a good rate performance.