Synthesis and electrochemical properties of La-doped Li4Ti5O12 as anode material for Li-ion battery

La-doped Li4Ti5O12 was successfully synthesized from Li2CO3, La2O3 and tetrabutyl titanate by a simple ball milling assisted modified solid-state method. The impact of La-doping on crystalline structure, particle size, morphology and electrochemical performance of Li4Ti5O12 was investigated. The samples were characterized by XRD, SEM, galvanostatically charge-discharge and electrochemical impedance spectroscopy. The results demonstrated that the in-situ coated and ball-milling method could decrease the particle size and prevent the aggregation of Li4Ti5O12. La-doping obviously improved the rate capability of Li4Ti5O12 via the generation of less electrode polarization and higher electronic conductivity. Li3.95La0.05Ti5O12 exhibited a relatively excellent rate capability and cycling stability. At the charge discharge rate of 0.5 C and 40 C, its discharge capacities were 176.8 mAh/g and 54.7 mAh/g. After 10 cycles, fairly stable cycling performance was achieved without obvious capacity fade at 0.5 C, 1 C, 2 C, 5 C, 10 C, 20 C and 40 C. In addition, compared to Li4Ti5O12, Li3.95La0.05Ti5O12 almost did not have the initial capacity loss. It indicated that Li3.95La0.05Ti5O12 was a promising candidate material for anodes in Li-ion battery application. (C) 2012 Elsevier Ltd and Techna Group S.r.l. All rights reserved.