Scalable High-Areal-Capacity Li–S Batteries Enabled by Sandwich-Structured Hierarchically Porous Membranes with Intrinsic Polysulfide Adsorption
Xiangcun Li, Yue Zhang, Shuting Wang, Yang Liu, Yu Ding, Gaohong He, Xiaobin Jiang, Wu Xiao, Guihua Yu
Abstract
The key to realizing practical applications of Li–S batteries lies in scalable fabrication of cathode materials with high sulfur-loading and strong binding of lithium polysulfides (LiPSs). We report a scalable CeO2–CNT@C porous membrane with a large porosity of 90%. Introducing CNTs is critical to increase the porosity and construct porous networks with CNTs as the skeleton and CeO2-doped carbon as the shell. The macropores can improve the transport of Li+ and electrolyte, while the porous networks possess high polysulfide-adsorbing and electron-transferring ability. The CeO2–CNT@C membrane can serve as an Al foil-free cathode and an interlayer for Li–S batteries. Moreover, CeO2 can immobilize LiPSs and can alleviate its shuttle effect. The Li–S batteries with a sulfur loading of 6.2 mg cm–2 deliver a capacity of 847 mA h g–1 after 100 cycles, showing a high areal capacity of 5.25 mA h cm–2 at a low electrolyte/sulfur ratio of 5.2 μL mg–1.