Selective ion transport of catalytic hybrid aerofilm interlayer for long-stable Li-S batteries

Abstract

Realistic prospects of high-energy and compact lithium-sulfur (Li-S) batteries promising as next-generation energy storages are hindered by their poor cycle life and severe self-discharge impelled through the polysulfide dissolution. Here, we report a feasible strategy to effectively suppress polysulfide and selectively control ions transport applying a new-type ultralight aerofilm membrane for practical Li-S batteries. Catalytic hybrid aerofilm interlayer (HAI) consisting of sulfonated tetrafluoroethylene and manganese dioxide nanowires suffices physical shield and sieve polysulfides through sulphophilicity polymer within the gaps of manganese dioxide layers, while also imparting chemical anchoring and catalysis of Mn-O. Such co-operative synergetic effects of the hybrid aerofilm interlayer for the Li-S cells enable the realization of a high discharge capacity of 1189 mAh g−1 at the end of the 500th cycle with a capacity retention of over 92.3 %, which is a 671 % improvement over sulfur battery with NO interlayer. Moreover, the aerofilm interlayer provides Li-dendritic growth inhibition and self-discharge prevention to retain the cycle life and safety of the device. This study presents a forward-looking strategy for developing an ultralight-compact and high-power Li-S battery.