Enhancing electrochemical performance of Mn doped LiFePO4 cathode materials for lithium-ion batteries
Haitao Yang, Ziwei Pan, Liang Wang, Chao Liu, Zhichun Wang, Chuanxu Zhang, Wenqiang Lu
Abstract
The Mn-doped LiFePO4/C cathode materials are prepared by high-temperature solid-phase process. The obtained products have ball-like morphologies with uniform carbon coating. As cathode for lithium-ion battery, the as-prepared LiMn0.02Fe0.98PO4/C composite exhibits excellent electrochemical properties, which delivers a discharge capacity of 154.7 mAh/g at 0.1 C. Significantly, a capacity of 100.4 mAh/g (1 C) at 0 oC can be obtained for LiMn0.02Fe0.98PO4/C cell, which is higher than that of LiFePO4/C cell (78.7 mAh/g) at same testing condition. After 100 cycles, the discharge capacity was 140 mAh·g-1 and the capacity retention rate was 98.6 %. LiMn0.02Fe0.98PO4/C composite was able to provide a discharge specific capacity of 88.2 mAh·g-1 even at high rates of 10 C, indicating its excellent rate capability and cycling stability.The improved performance of Mn doped LiFePO4/C is due to the embedding and stripping ability of Li+ in LiFePO4 lattice is improved. This study can provide directions for improving the electrochemical performance of LiFePO4 materials.