Modification of phosphorus-doped carbon coating enhances the electrochemical performance of LiFe0.8Mn0.2PO4 cathode material

Abstract

Abstract Overcoming the shortcomings related to low conductivity and slow ion diffusion for olivine-type transition metal phosphates is of vital significance to broaden their applicability in rapid charging devices. Herein, the modification of phosphorus-doped carbon coating is performed on LiFe0.8Mn0.2PO4 (LFMP) to prepare LFMP/C-P via a novel sol-gel hydrothermal method. Results of the morphology and electrochemical performance tests indicate that a three-dimensional conductive channel is formed surrounding the well-distributed LFMP/C-P nanoparticles to promote ion and electron transmission. Moreover, the phosphorus-doped carbon coating not only enhances the electronic conductivity, which guarantees the rapid electronic transfer as an electron donor through the “carrier conduction” mechanism, but also connects the carbon coating and material bulk as a bridge. These characteristics endow the LFMP/C-P composite with excellent electrochemical performances, e.g., a reversible discharge specific capacity of 93.6\xa0mAh\xa0g−1 at 10\xa0C and a capacity retention rate of 86.44% after 700 cycles at 10\xa0C. This study provides a strategy to improve the rapid charge-discharge performance of electrode materials for lithium-ion batteries.