碳材料形貌与结构对锂离子电池循环性能影响

Study on cyclic properties of lithium ion batteries by morphology and structure of carbon materials

采用球形石墨、磷片形石墨、无定型炭黑三类不同形貌和晶体结构的碳材料作为锂离子负极材料并制备扣式电池。结合扫描电子显微镜法(SEM)、X射线衍射光谱法(XRD)以及氮气吸附脱附测试等手段对材料的形貌和晶体结构进行物理性能的分析,并通过电化学性能测试探究碳材料形貌和晶体结构对锂离子电池循环性能的影响。结果表明采用无定型炭黑制备的锂离子电池具有良好的循环性能,0.1 C下首次放电比容量为334.94 mAh/g,1 C下循环300次后容量保持率为95.1%。

The carbon materials of spherical graphite,phosphorous graphite and amorphous carbon black with different morphologies and crystal structures were used as lithium ion anode materials to prepare button cells.The physical properties of the material's morphology and crystal structure were analyzed by means of SEM,XRD and BET.The effects of carbon material morphology and crystal structure on the cycle performance of lithium ion battery were investigated by electrochemical performance test.Compared with the three,the structure shows that the lithium ion battery prepared by the amorphous graphite has good cycle performance.The first discharge specific capacity is 334.94 mAh/g at 0.1 C,and the capacity retention rate is 95.1%at 300 times under 1 C.