Sandwiched Cathodes Assembled from CoS<sub>2</sub>‐Modified Carbon Clothes for High‐Performance Lithium‐Sulfur Batteries
Jun Xu, Likun Yang, Shoufu Cao, Jingwen Wang, Yuanming Ma, Junjun Zhang, Xiaoqing Lü
Abstract
Abstract Structural design of advanced cathodes is a promising strategy to suppress the shuttle effect for lithium‐sulfur batteries (LSBs). In this work, the carbon cloth covered with CoS 2 nanoparticles (CC‐CoS 2 ) is prepared to function as both three‐dimensional (3D) current collector and physicochemical barrier to retard migration of soluble lithium polysulfides. On the one hand, the CC‐CoS 2 film works as a robust 3D current collector and host with high conductivity, high sulfur loading, and high capability of capturing polysulfides. On the other hand, the 3D porous CC‐CoS 2 film serves as a multifunctional interlayer that exhibits efficient physical blocking, strong chemisorption, and fast catalytic redox reaction kinetics toward soluble polysulfides. Consequently, the Al@S/AB@CC‐CoS 2 cell with a sulfur loading of 1.2 mg cm −2 exhibits a high rate capability (≈823 mAh g −1 at 4 C) and delivers excellent capacity retention (a decay of ≈0.021% per cycle for 1000 cycles at 4 C). Moreover, the sandwiched cathode of CC‐CoS 2 @S/AB@CC‐CoS 2 is designed for high sulfur loading LSBs. The CC‐CoS 2 @S/AB@CC‐CoS 2 cells with sulfur loadings of 4.2 and 6.1 mg cm −2 deliver high reversible capacities of 1106 and 885 mAh g −1 , respectively, after 100 cycles at 0.2 C. The outstanding electrochemical performance is attributed to the sandwiched structure with active catalytic component.