An electrochemical study of Li insertion in the αII, γ and δ forms of VOPO4 and the optimization of their cycling performance are presented. The potentials of the intercalation–deintercalation processes and the specific capacities upon discharge have been correlated to the crystal structures of these phases. It is evidenced that the obtained capacities can be improved up to eight times by optimizing the synthesis route or the carbon/active material contact.