Preparation of LiMnxFe1-xPO4 Composites with dual coating carbon by hydrothermal method
作者单位：School of Chemistry and Chemical EngineeringHenan Institute of Science and Technology
会议名称：《河南省化学会2018年学术年会》
会议日期：2018年
学科分类：081704[工学-应用化学] 08[工学] 0817[工学-化学工程与技术] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学]
关 键 词：LiMnPO4 Cathode materials Li ion batteries Hydrothermal method
摘 要：Li FePO suffers from a lower energy density, and LiMnPO suffers from poor electronic and ionic conductivity. Iron-substituted Li MnPO(LiMnxFe-xPO) composites can complement each others shortcomings and synergistically increase the material’s energy density and power density. In this paper, the graphene and sucrose were used as the double carbon source to increase the electronic conductivity and ion diffusion of Li MnxFe-xPO,. The precursors with dual carbon layers were prepared by the improved hydrothermal method, followed by thermal conversion under high temperature. The effects of the coating carbon, lithium content, and the reaction solvent on the structure and electrical properties of the material was investigated. The results showed that when the molar ratio of Li:M(Fe+Mn):P was 1:1:3 with ethylene glycol as solvent, the Li MnxFe-xPO@C with double carbon layer possessed the best electrochemical performance with a specific discharge capacity of 120 m Ah/g at 0.1 C. and capacity retention with about 85% after 50 cycles. The excellent electrochemical performance is mainly attributed to the coating the double carbon layer, the dispersibility of the ethylene glycol, and the appropriate lithium content.