High rate performance of LiFePO_4 cathode materials co-doped with C and Ti~(4+) by microwave synthesis

摘要

Nanostructured LiFePO_4 powder with a narrow particle size (ca. 100 nm) for high rate lithium-ion battery cathode application was obtained by microwave heating and using citric acid as carbon source. The microstructures and morphologies of the synthesized materials were investigated by X-ray diffraction and scanning electron microscope while the electrochemical performances were evaluated by galvanostatic charge—discharge. The carbon coating and Ti~(4+) could improve the conductivity both between the LiFePO_4 particles and the intrinsic electronic conductivity. The LiFePO_4 doped with 5% C and 1% T~(4+) resulted in a specific capacity of 114-95 mAh-g~(-1) and 102-4 mAh-g~(-1) at discharge rates of 0-3C and 1C, respectively, and the cycle performance is very good.