基体碳材料对锂硫电池性能影响的研究

The effect of the matrix carbon materials influence on the performance of lithium-sulfur battery

采用乙炔黑、土状石墨、Cabot Vulcan XC-72炭黑、Cabot Bp2000超级导电炭黑作为硫载体制备了一系列含硫复合材料。通过X射线粉末晶体衍射(XRD)、扫描电子显微镜(SEM)、比表面积分析(BET)等分析测试手段对材料的物理性能进行表征,利用电池测试系统对材料的电化学性能进行了测试。结果表明基体材料表面结构、孔径分布及比表面积等因素都对复合材料的电化学性能造成影响,综合性能最好的基体材料为BP2000超级导电炭黑,其初始放电比容量高达1385.1mAh/g,在室温下经过30次循环之后电池放电比容量仍保持在1080.2mAh/g,容量保持率高达78%。

A series of sulfur composite materials which used acetylene black,aphanitic graphite,Cabot Vulcan XC-72 carbon black and Cabot Bp2000 super conductive carbon black were prepared.The physical structures were determined by X-ray diffraction,scanning electron microscopy and specific surface area measurements.The electrochemical performances of the sulfur composite material were characterized by cycling test.The results indicate that factors such as surface morphology,pore size distribution and specific surface area of the matrix materials can affect the electrochemical performance of the composite materials.In this paper,the best matrix material is Bp2000 super conductive carbon.Its initial discharge specific capacity is 1385.1mAh/g.The specific capacity still keep as high as 1080.2mAh/g,after 30 cycles at room temperature just 22% fade.