锂离子电池微晶石墨复合材料的制备及电性能研究

Preparation and electrochemical performance of composite microcrystalline graphite for lithium-ion battery

动力锂离子电池对负极材料的综合性能和成本提出更高的要求。本文以微晶石墨为原料,X-8沥青作为包覆剂和黏结剂,通过一体化粉碎整形和二次造粒制得一种复合微晶石墨,其首次可逆比容量和库伦效率分别达到354.4 mA·h/g和92.2%。在LiFePO_4/C电池体系中,1 200次循环后电池的容量保持率达到91%。

Advanced lithium ion batteries for EVs require high performance and low cost anode materials. In this study, the microcrystalline graphite is selected as raw material and X-8 pitch is used as the coating agent and binder. The composite mierocrystalline graphite, with a reversible capacity of 354.4 mA·h/g and initial columbic efficiency of 92.2%, is prepared by a novel pulverization method and secondary granulation process. The LiFePO4/C battery, using the composite microcrystalline graphite as anode material, displays a good cycle performance with a capacity retention of 91% after 1 200 cycles.