Electrochemical performance of Li2FeSiO4 as a new Li-battery cathode material

Phase-pure lithium iron silicate (Li2FeSiO4) has been prepared successfully. Its ambient temperature structure has been determined by X-ray diffraction and its electrochemical performance characterised at 60 °C. The resulting cyclic voltammogram suggests a phase transition to a more stable structure after the first cycle. This could involve a structural ordering process from a solid-solution to a long-range-ordered structure. The initial charge capacity of 165 mAh/g (99% of the theoretical value) stabilises after a few cycles to around 140 mAh/g (84% of the theoretical value).