Understanding and recent development of carbon coating on LiFePO4 cathode materials for lithium-ion batteries

Abstract

Olivine-structured LiFePO₄ has been the focus of research in developing low cost, high performance cathode materials for lithium ion batteries. Various processes have been developed to synthesize LiFePO₄ or C/LiFePO₄ (carbon coating on LiFePO₄), and some of them are being used to mass produce C/LiFePO₄ at the commercial or pilot scale. Due to the low intrinsic electronic and ionic conductivities of LiFePO₄, the decrease of particle size and the nano-layer of carbon coating on LiFePO₄ particle surfaces are necessary to achieve a high electrochemical performance. Significant progress has been made in understanding and controlling phase purity, particle size and carbon coating of the C/LiFePO₄ composite material in the past. However, there are still many challenges in achieving a high quality product with high consistency. In this review, we summarize some of the recent progress and advances based on selected reports from peer-reviewed journal publications. Several typical synthesis methods and the effect of carbon coating quality on the properties of C/LiFePO₄ composite are reviewed. An insight into the future research and further development of C/LiFePO₄ composite is also discussed.