【作者】 鲁盼盼； 朱华丽； 陈召勇；

【Author】 Panpan Lu,Huali Zhu,Zhaoyong Chen* School of physics and electronic science,Changsha University of Science and Technology,No.960,Section 2,Wanjiali South RD,Changsha,Hunan Province,P.R.China,410004

【机构】 长沙理工大学物理与电子科学学院；

【摘要】 以沥青作为表面修饰剂对天然石墨进行包覆,并经过高温炭化热处理形成炭包覆天然石墨的复合材料。分别采用X射线衍射仪(XRD)、扫描电子显微镜(SEM)和蓝电电池测试系统等对沥青包覆天然石墨前后的样品进行结构、形貌和电化学性能分析。XRD分析结果表明,经沥青包覆热处理后,样品的d002、La和Lc均随包覆量的增加而变大,且有序化程度降低,表明沥青成功包覆在了天然石墨表面;SEM图片显示天然石墨表面包覆了一层无定形炭;电化学性能测试结果表明,采用沥青包覆改性后的天然石墨在0.1C首次脱锂容量高达506.4mAh/g,在0.2C下25次循环后脱锂容量为413.4mAh/g,而未经处理的天然石墨脱锂容量仅为277.8mAh/g(0.2C下25次循环后),包覆后有利于比容量的提高。更多还原

【Abstract】 Carbon-coated natural graphite composite was prepared by carbonization of asphalt-coated natural graphite at high temperature.X-ray diffraction(XRD),Scanning electron microscopy(SEM) and Land battery test system were used to characterize the crystal structure,morphology and electrochemical properties of samples.XRD results showed that asphalt successfully coated on the surface of natural graphite because d002,La and Lc increased with the increased of coated amount and the order degree decreased.SEM images indicated that the surface of natural graphite was coated with a layer of amorphous carbon.Electrochemical performance revealed that the initial lithium-deinsertion capacity of modified natural graphite was 506.4mAh/g at 0.1C and it remained 413.4mAh/g after 25 charge-discharge cycles at 0.2C while lithium-deinsertion capacity of untreated natural graphite was only 277.8mAh/g(after 25 cycles at 0.2C).Coating modification is benefit for improving the capacity of natural graphite.更多还原