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

Abstract

Abstract La-doped Li 4 Ti 5 O 12 was successfully synthesized from Li 2 CO 3 , La 2 O 3 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 Li 4 Ti 5 O 12 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 Li 4 Ti 5 O 12 . La-doping obviously improved the rate capability of Li 4 Ti 5 O 12 via the generation of less electrode polarization and higher electronic conductivity. Li 3.95 La 0.05 Ti 5 O 12 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 Li 4 Ti 5 O 12 , Li 3.95 La 0.05 Ti 5 O 12 almost did not have the initial capacity loss. It indicated that Li 3.95 La 0.05 Ti 5 O 12 was a promising candidate material for anodes in Li-ion battery application.