Building a stable artificial solid electrolyte interphase on lithium metal anodes toward long-life Li–O2 batteries

Rechargeable Li–O2 batteries (LOBs) are considered as a promising battery technology due to their high energy density. The performance of the batteries, however, is limited by inevitable chemical/electrochemical corrosion and uncontrollable Li dendrite growth. Here, a uniform and dense LiF artificial solid electrolyte interphase (SEI) is introduced to address these issues. This LiF layer with rich and uniform crystal boundary can homogenize the Li-ion flux on Li metal anodes (LMAs) surface and thus accomplish planar Li deposition under the LiF layer, improving the interfacial stability of LMAs. In addition, the dense LiF layer enables high corrosion resistance against the electrolyte and air. As a result, the symmetric cells with LiF layer coated Li anodes (LiF@Li) show stable polarization voltage and long cycle life up to 1000 h. Moreover, the Li–O2 battery with LiF@Li shows excellent cycle stability up to 150 cycles at an ultrahigh current density of 4.50 mA cm−2. This work illustrates a promising way for the unfettered development of advanced LOBs.