Electrochemical lithium insertion in β-MoO3:: novel LixMoO3 bronzes

New lithium molybdenum bronzes have been synthesized by electrochemical lithium insertion. Through electrochemical spectroscopy techniques we have detected that lithium insertion proceeds at least in a two-step reduction process. The maximum amount of lithium inserted in beta-MoO3 leads to a high specific capacity of the cell of 370 Ah kg(-1). However, this capacity was lost after the first charge-discharge cycle, resulting in a total loss of 25%, due to structural transformations. The structural study of the insertion process showed that each step of the process can be associated with the formation of different single phases of variable composition, LixMoO3.