A novel SnxSbNi composite as anode materials for Li rechargeable batteries

The approach of carbothermal reduction was employed to prepare the micro-sized SnxSbNi composites used as anode material for rechargeable lithium-ion batteries. The synthesized spherical SnxSbNi particles show a loose micro-sized structure and a multi-phase composition. The effect of Sn content in SnxSbNi on the electrochemical properties of the SnxSbNi composite anode was investigated. Increasing the amount of tin in SnxSbNi composite leads to an increase in the reversible discharge capacity, however, excessive introduction of Sn into SnxSbNi alloy will cause the fast capacity decline of electrode. Sn2SbNi alloy provides a reversible specific capacity over 660 mAh g−1 and an initial capacity loss of 120 mAh g−1 with an excellent cycleability. The low initial capacity loss is attributable to the large particle size of SnxSbNi powders, while the excellent cycling stability is ascribed to the loose particle structural characteristics and multi-phase features. The former could accommodate the volume change of electrode, while the latter will result in a stepwise lithiation/delithiation behavior and thus a smooth volume change of electrode in cycles.