Impact of the crystalline phase of binary silicide on its lithiation and delithiation properties

Abstract

In this work, we investigate the impact of the crystalline phase of binary silicide on its lithiation and delithiation properties. Charge–discharge testing shows that the reversible capacity is not dependent on the amount of Si included in the silicide; the capacity was found to be independent of the composition of the silicide even in the case of a given transition metal making up the silicide. The results of this study confirm that there is no phase separation of the silicide during the charge–discharge reactions. A high reversible capacity could be obtained when the affinity of the transition metal for Li was large and the distance between the Li atoms and the nearest-neighbour atom in lithiated silicide was large.