Journal of Power Sources, Vol.189, No.1, 655-659, 2009
Electrochemical performance of La-Co-Sn alloys as anode materials for Li-ion batteries
Sn-rich La-Co-Sn ternary alloys were obtained by arc-melting process and Subsequent ball-milling. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to determine the structure and morphology of the obtained alloys. In addition, the galvanoststic discharge/charge test, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were carried out to characterize the electrochemical properties of these alloys as anode materials for Li-ion batteries. It is found that all the as-cast La-Co-Sn ternary alloys have the same main phase of La3CO4Sn13 and low electrochemical capacities. Among these alloys, the as-cast LaCoSn4 alloy exhibits the best electrochemical performance. The ball-milling process results in the reduced cystallinity, and the enhanced electrochemical capacities as compared to the as-cast alloy. In particular, the LaCoSn4 alloy, obtained after ball-milling for 16 h, provides the higher reversible discharge capacity and the better cycle stability. (C) 2008 Elsevier B.V. All rights reserved.