Boosting the Cycle Life of Aprotic Li–O2 Batteries via a Photo‐Assisted Hybrid Li2O2‐Scavenging Strategy

Abstract

AbstractThe development of the nonaqueous Li–O2 battery, a promising candidate for high‐gravimetric‐energy‐storage techniques, is seriously restrained by the high charge overpotential during electrochemical decomposition of insulating Li2O2. Benefiting from the photovoltage, photo‐assisted charging is revealed as a feasible method to reduce the charge potential. However, a long period of illumination will inevitably aggravate the degradation of the electrolyte. Herein, composed of contact‐ion‐pairs (CIPs), a newly introduced superconcentrated electrolyte presents superior stability against parasitic photocatalytic decomposition. More significantly, the conventional and photo‐assisted charging processes are rationally integrated as a unique hybrid strategy, in which the highly polarized charging stage is replaced by the photo‐assisted Li2O2‐scavenging process. By tuning the photocatalysis and Li2O2 electrochemical oxidization, the hybrid Li2O2‐scavenging strategy not only boosts the cycle life of rechargeable Li–O2 batteries but also opens possibilities in designing photocatalysis‐involved rechargeable energy‐storage battery systems.