Structure and Characterization of LiFe_(0.99)M_(0.01)PO_4/C Electrodes

In latest studies we confirmed that the PAM (polyacrylamide) templated LiFePO4/C composite was nano-structured with better rate property and higher specific capacity, compared with the undoped LiFePO4. In this article we further synthesized metal ions doped phosphates by this templating method, and all the capacities of those LiFe0.99M0.01PO4/C (M=Nd3+, Co3+, Cr3+, Mn3+) composites were enhanced. When discharging at C/3 rate the capacity of LiFePO4/C composite was only 108mAh·g-1, while those of the doped LiFe0.99M0.01PO4/C were respectively 140, 129, 120 and 115mAh·g-1. And the cycliabilities were also stable. Researches show that the conductivities of those doped materials are improved by 5~7 magnitude, which are close to those in references. XRD patterns show that those doped materials still remain their ordered olivine structure.