LiMn<sub>0.8</sub>Fe<sub>0.2</sub>PO<sub>4</sub>/C Nanoparticles via Polystyrene Template Carburizing Enhance the Rate Capability and Capacity Reversibility of Cathode Materials
Yan Wang, Fubao Yong, Zhihua Wang, Miao Wang, Qian Peng, Min Zhao, Zhen Chen, Qi Huang, Shanshan Yang, Faquan Yu
Abstract
In order to unlock the electrochemical performance ability of manganese-based lithium ferromanganese phosphate cathode materials, CP 1 –LiMn 0.8 Fe 0.2 PO 4 /C (coprecipitation) nanocomposites were prepared by introducing polystyrene nanospheres as templates and carbon sources into the coprecipitation method combined with a multistage carburizing heat treatment. In the processes of heat treatment, polystyrene nanospheres can not only build a conductive carbon layer and optimize the electron transport path but also refine the particles and inhibit the nanoparticle aggregation. The interconnected conductive carbon coating significantly improves the diffusion coefficient of lithium ions, which assists LiMn 0.8 Fe 0.2 PO 4 in lifting discharge specific capacity and cycle performance. The test results show that the as-prepared CP 1 –LiMn 0.8 Fe 0.2 PO 4 /C shows superior rate capability (130.5 mAh g –1 at 0.1C and 92.8 mAh g –1 at 5C) and capacity reversibility (95.5% after 200 cycles at 0.5C).