Enhanced low-temperature performance of slight Mn-substituted LiFePO4/C cathode for lithium ion batteries

LingJie Zeng, Qiang Gong, XiaoZhen Liao, Li He, YuShi He, ZiFeng Ma
2011 Chinese Science Bulletin  
Low temperature performance of LiFePO 4 /C cathode was remarkably improved by slight Mn-substitution. Electrochemical measurements showed that about 95% of the discharge capacity of LiFe 0.98 Mn 0.02 PO 4 /C cathode at 20°C was obtained at 0°C, compared to 85% of that of LiFePO 4 /C cathode. The LiFe 0.98 Mn 0.02 PO 4 /C sample also presented enhanced rate performance at -20°C with the discharge capacities of 124.4 mA h/g (0.1C), 99.8 mA h/g (1C), 80.7mAh/g (2C) and 70 mA h/g (5C),
more » ... (5C), respectively, while pristine LiFePO 4 /C only delivered capacities of 120.5 mA h/g (0.1C), 90.7 mA h/g (1C), 70.4 mA h/g (2C) and 52.2 mA h/g (5C). Cyclic voltammetry measurements demonstrated an obvious improvement of the lithium insertion-extraction process of the LiFePO 4 /C cathode by slight Mn-substitution. The results of FSEM observation and electrical conductivity measurement indicated that slight Mn-substitution minimized the particle size of LiFe 0.98 Mn 0.02 PO 4 /C and also obviously improved the electrical conductivity of the compound, thus obviously enhances the interface reaction process on the cathode. low-temperature performance, Mn-substitution, LiFePO 4 /C cathode, lithium ion batteries Citation: Zeng L J, Gong Q, Liao X Z, et al. Enhanced low-temperature performance of slight Mn-substituted LiFePO 4 /C cathode for lithium ion batteries.
doi:10.1007/s11434-010-4097-0 fatcat:bil7oagjarb7xkx7jj73u5ptbi