High rate cathode Li3V2(PO4)3/C with an excellent electrochemical performance has been successfully synthesized via an in-situ copolymerization method. The synthesized Li3V2(PO4)3/C composite exhibits an extraordinary reversible discharge capacity of 103.1 mAh g−1 at 50 C discharge rate. In addition, there are no obvious capability fade after 100 cycles. The carbon from pyrolysis of polyacrylamide obtained from the in-situ copolymerization reaction is believed acting a critical role in acquiring such high performances.