Liang Xinghua, Zhang Yu, Ning Yujuan, Huang Dongxue, Lan Linxiao, Li Siying
Guangxi Key Laboratory of Automobile Components and Vehicle Technology, Guangxi University of Science and Technology, Liuzhou 545006, China.
Nanomaterials (Basel). 2022 Jul 29;12(15):2614. doi: 10.3390/nano12152614.
Solid-state lithium sulfur batteries are becoming a breakthrough technology for energy storage systems due to their low cost of sulfur, high energy density and high level of safety. However, its commercial application has been limited by the poor ionic conductivity and sulfur shuttle effect. In this paper, a nitrogen-doped porous carbon fiber (NPCNF) active material was prepared by template method as a sulfur-host of the positive sulfur electrode. The morphology was nano fiber-like and enabled high sulfur content (62.9 wt%). A solid electrolyte membrane (PVDF/LiClO/LATP) containing polyvinylidene fluoride (PVDF) and lithium aluminum titanium phosphate (Li.Al.Ti.(PO)) was prepared by pouring and the thermosetting method. The ionic conductivity of PVDF/LiClO4/LATP was 8.07 × 10 S cm at 25 °C. The assembled battery showed good electrochemical performance. At 25 °C and 0.5 C, the first discharge specific capacity was 620.52 mAh g. After 500 cycles, the capacity decay rate of each cycle was only 0.139%. The synergistic effect between the composite solid electrolyte and the nitrogen-doped porous carbon fiber composite sulfur anode studied in this paper may reveal new approaches for improving the cycling performance of a solid-state lithium-sulfur battery.
固态锂硫电池因其硫成本低、能量密度高和安全性高，正成为储能系统的一项突破性技术。然而，其商业应用受到离子电导率差和硫穿梭效应的限制。本文采用模板法制备了一种氮掺杂多孔碳纤维（NPCNF）活性材料作为正极硫电极的硫宿主。其形态为纳米纤维状，硫含量高（62.9 wt%）。通过浇注和热固化法制备了一种含有聚偏氟乙烯（PVDF）和锂铝钛磷酸盐（Li.Al.Ti.(PO)）的固体电解质膜（PVDF/LiClO/LATP）。PVDF/LiClO4/LATP在25℃时的离子电导率为8.07×10 S cm。组装后的电池表现出良好的电化学性能。在25℃和0.5 C下，首次放电比容量为620.52 mAh g。500次循环后，每个循环的容量衰减率仅为0.139%。本文研究的复合固体电解质与氮掺杂多孔碳纤维复合硫阳极之间的协同效应可能为提高固态锂硫电池的循环性能揭示新的途径。
