Synthesis of LiFe_(0.4)Mn_(0.6-x)Ni_xPO _4/C by co-precipitation method and its electrochemical performances

摘要

LiFe_(0.4)Mn_(0.6-x)NixPO_4/C(x = 0, 0.05, 0.1, and 0.2) composite cathode materials for lithium ion batteries have been prepared by the co-precipitation method using oxalic acid as a precipitator. The structure and morphology of precursors and products have been investigated. Electrochemical tests demonstrate that LiFe_(0.4)Mn _(0.55)Ni_(0.05)PO_4 can deliver a specific capacity of 142 mAh g~(-1) at 0.1 C, and retains 133 mAh g~(-1) after 60 cycles. The rate performance of LiFe_(0.4)Mn_(0.6)PO_4 is obviously improved by doping Ni. The capacity of LiFe_(0.4)Mn _(0.55)Ni0.05PO4 at 2 C is 110 mAh g~(-1)