Halosilane triggers anodic silanization and cathodic redox for stable and efficient lithium–O2 batteries

Abstract

Fundamental challenges with the inefficient decomposition of Li₂O₂, the undesirable “shuttled effects” reactions of redox mediators (RMs) with Li, and the anodic corrosion from electrolyte attacks have seriously hindered the development of Li–O₂ batteries. We create and study a self-defense indissoluble LiOSi(CH₃)₃ layer based on halosilane (iodotrimethylsilane, TMSI) tethered to a rationally designed oxygen-pretreated-Li (OPL) anode to overcome most above stubborn challenges. The silanization layer is shown to protect the Li anode against parasitic reactions and also stabilize Li electrodeposition during cell cycling. Iodine species self-released during the anchoring reaction can function as RMs at the cathode, reducing the charge overpotential. Finally, the combination of self-defense and self-release approaches through solely introducing halosilane into liquid electrolytes endows lithium–O₂ batteries with excellent cycling stability and electrical energy efficiency.