Influence of electrode microstructure on the reactivity of Cu2Sb with lithium

The reactivity of lithium with Cu2Sb was recently described to be governed by displacement reactions of Cu similar to those occurring in Cu2.33V4O11. In order to complement the earlier work of Fransson et al., we have revisited the electrochemical reactivity of Cu2Sb with Li. Through a different arsenal of characterization techniques, we have emphasized the role of the particle size, electrode preparation and temperature on the reversibility of the electrochemical reaction. We have demonstrated that the structural reversibility of the Cu2Sb electrode can be obtained in two special cases: (1) when the particle size of Cu2Sb is small and when the powders are ball milled with carbon and (2) when Li2CuSb is used as the starting material and some Sb is lost from the electrode during charge.