Comparison of the Rate Capacities of LiFePO4 Cathode Materials

In this paper, the specific capacities as a function of discharge rate of over 40 different LiFePO4 materials reported were reviewed and analyzed. The influence of synthesis route, particle size, doping, carbon coating, and conductive carbon loading on the rate performance was discussed. The capacity distribution of the existing LiFePO4 materials over a wide discharge rate (0.1 - 60C) was constructed. Analysis of the experimental data indicates that carbon coating has a more significant effect in improving the rate performance as compared to doping and particle size reduction. With highly conductive carbon coating, some of the LiFePO4 materials with a large particle size (150-300 nm) exhibited better performance than the materials of nanosize (30-100 nm). In terms of synthesis method, excellent high rate performance was achieved in the LiFePO4 materials prepared by direct precipitation, sol-gel, polyol, and ballmilling techniques. (C) 2010 The Electrochemical Society. [DOI: 10.1149/1.3460840] All rights reserved.