Stable cycle-life properties of Ti-doped LiFePO4 compounds synthesized by co-precipitation and normal temperature reduction method

Submicron-sized LiFePO4 and Ti-doped LiFePO4 cathode materials were synthesized by a reformative co-precipitation and normal temperature reduction method, for which Ti ions were added in the process of preparing precursors to pursue a kind of sufficient and homogenous doping way. ICP and XRD analyses indicate that Ti ions were sufficiently doped in LiFePO4 and did not alter its crystal structure. It is noted that higher Ti ions doping levels are conducive to electrochemical performance of LiFePO4, especially on the aspect of stable cycle-life at higher C rates. The sample doped with 3 at% Ti shows the most impressive cycling performance, even after 100 cycles, discharge capacity of 133 mAh g−1 was obtained (102.3% of its initial value) at 1C rate, and the discharge decreased little from 124 to 120 mAh g−1 (96.8% of its initial value) at 2C rate.