Scalable High-Areal-Capacity Li-S Batteries Enabled by Sandwich-Structured Hierarchically Porous Membranes with Intrinsic Polysulfide Adsorption.

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.