Flexible rGO @ Nonwoven Fabrics' Membranes Guide Stable Lithium Metal Anodes for Lithium-Oxygen Batteries

Lithium-oxygen (Li-O2) batteries are outstanding as next-generation energy-storage devices because of their extremely high theoretical specific energy density. However, their practical application is hindered by various issues from both unstable electrodes and electrolyte. Notably, the uncontrollable growth of a lithium dendrite and severe lithium pulverization deteriorates the practical energy density and service life of Li-O2 batteries. Here we build a flexible protective membrane, which is reduced graphene oxide coated on nonwoven fabrics (rGO @ NWF), for a stable Li metal anode/electrolyte interface via a simple dipping-penetration and in situ electrochemical reduction strategy. The lowest lithium nucleation overpotential on rGO sheets results in the uniform lithium deposition behavior on the Li anode surface with the rGO protective nanofilm after different plating capacities, which is demonstrated by SEM analysis. The cycling life of the Li-O2 cell with a rGO@NWF membrane extended to more than 500 cycles under the limited capacity of 500 mA h g-1, which is about 3-fold that of the pure Li anode. This work demonstrates a scalable approach to inhibit the growth of the lithium dendrite and corrosion of Li metal anodes by rGO nanofilm for long-term cycling Li-O2 batteries, holding an excellent potential for the development of other lithium metal batteries.