人造SEI膜硅/炭负极材料的制备及性能研究

Preparation and properties of artificial SEI film silicon/carbon anode materials

用砂磨机匀浆并旋蒸干燥、预炭化、炭化制备了硅酸锂人造SEI膜硅/炭负极材料。通过XRD、SEM等研究了所制备材料的结构与形貌,通过电化学循环、CV、EIS等研究了样品的电化学性能。结果表明,添加3%碳酸锂时制备的人造SEI膜硅/炭负极材料具有最优的电化学性能:首次充放电效率高达88.1%,在200 mA/g电流密度条件下循环50次后,充电容量仍能保持在1 103.5 mA·h/g。

The lithium silicate artificial SEI film silicon/carbon anode material is prepared by homogenization with a sand mill,steam drying,pre-carbonization and carbonization.The structure and morphology of the prepared materials are studied by XRD and SEM.The electrochemical properties of the samples are investigated by electrochemical cycle,CV and EIS.The results show that the artificial SEI film silicon/carbon anode material prepared by adding 3%lithium carbonate has the best electrochemical performance:the first charge and discharge efficiency is as high as 88.1%,and the capacity can still maintain at 1103.5 m A·h/g after 50 cycles at 200 mA/g current density.