Zhu Zhijun, Yu Zhihong, Chen Guihuan, Li Boyan, Li Aiju
School of Chemistry, South China Normal University, Guangzhou, 510006, China.
Chempluschem. 2025 Jan;90(1):e202400416. doi: 10.1002/cplu.202400416. Epub 2024 Nov 13.
Lithium-sulfur (Li-S) batteries display promise as redox-based batteries, where separators are an essential part of preventing short-circuiting of the positive and negative electrodes, while the shuttle effect is a critical issue of separators. Currently, commercial PP separators are weak in inhibiting the polysulfides shuttling, so modified separators are needed to inhibit it to improve the battery performance. This paper reports that CeVO/KB composites act as separator materials. CeVO/KB modified PP separators enhanced the adsorption of LiPSs, accelerated the rate of Li migration, and catalyzed the conversion of LiPSs. These bring about the effect that CeVO/KB/PP batteries reach 1200.9 mAh g in the first cycle with a capacity retention rate of 86.5 % after 100 cycles at 0.2 C and reach 882.7 mAh g of the initial cycle with a capacity decay rate of 0.063 % after 1000 cycles at 3 C. This work introduces rare earth metal vanadates to modify the separator, adding new ideas for designing separators for good-performance batteries.
锂硫（Li-S）电池作为基于氧化还原的电池展现出了前景，其中隔膜是防止正负极短路的关键部件，而穿梭效应是隔膜的一个关键问题。目前，商用聚丙烯（PP）隔膜抑制多硫化物穿梭的能力较弱，因此需要对隔膜进行改性以抑制穿梭效应，从而提高电池性能。本文报道了CeVO/KB复合材料可作为隔膜材料。CeVO/KB改性的PP隔膜增强了对多硫化锂（LiPSs）的吸附，加快了锂迁移速率，并催化了LiPSs的转化。这些使得CeVO/KB/PP电池在首次循环时达到1200.9 mAh g，在0.2 C下100次循环后容量保持率为86.5%，在3 C下1000次循环后初始循环容量为882.7 mAh g，容量衰减率为0.063%。这项工作引入稀土金属钒酸盐对隔膜进行改性，为设计高性能电池的隔膜提供了新思路。
