聚合物固态电解质在锂硫电池中的应用

Application of solid polymer electrolyte in lithium sulfur batteries

采用微观和宏观包覆两种方式制备聚合物固态电解质包覆的硫@碳纤维复合固态电极,利用扫描电镜、元素分析和电化学测试表征电极的微观形貌,研究相应锂硫电池的电池性能。结果表明:微观的聚合物固态电解质包覆活性材料的电极结构有利于离子传输;电极表面宏观构建一层聚合物固态电解质薄膜有助于改善电极的循环稳定性,抑制穿梭效应;利用膜电极结构组装的全固态锂硫电池具有良好的循环性能,循环270次后库仑效率仍保持98%以上。

Polymer electrolyte coated sulfur@carbon fiber composite solid electrode was prepared by the two methods of microscopic and macroscopic coating with polymer electrolyte in the cathode sheet of lithium sulfur battery. The microscopic morphology of the electrode was characterized by scanning electron microscopy, and the corresponding performances of the battery with different cathode structures were also analyzed. Results show that the electrode structure of microscopic polymer solid electrolyte coated active material is favorable for ion transfer. Macroscopically constructing a polymer solid electrolyte film on the electrode surface can improve the cyclic stability of the electrode and inhibit the shuttle effect. The all-solid lithium-sulfur battery assembled with the membrane electrode structure has good cycle performance. After 270 cycles, the Coulomb efficiency still keeps over 98 %.