Nano-sized SnSbCu x alloy anodes prepared by co-precipitation for Li-ion batteries

Abstract

Nano-sized SnSbCu x alloy anode materials are prepared by reductive co-precipitation method combining with the aging treatment in water bath at 80 °C. The microstructure, morphology and electrochemical properties of synthesized SnSbCu x alloy powders are evaluated by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM) and galvanostatical cycling tests. The results indicate that the average particle size is reduced and the Cu 6Sn 5, Cu 2Sb phases appear successively along with the increase of Cu content in the SnSbCu x alloy. The reduction of average particle size, the existence of inactive element Cu and the complex multi-step reaction mechanism in SnSbCu x alloy anodes are propitious to improve the structure stability and thus improve the cycling performance. When cycled at a constant current density of 0.1 mA cm −2 between 0.02 and 1.50 V, the coulomb efficiency of first cycle exceeds 74% and the reversible capacity of 20th cycle attains to 490 mAh g −1 in SnSbCu 0.5 alloy anode.