Insoluble Solid Organic Catalysts for Non-Aqueous Lithium-Air Batteries

Abstract

The chemistries based on the Li-O2 couple in aprotic electrolyte seem promising to provide ultrahigh-energy density values and outperform the current LIB technology. The main targeted application is to power electrified vehicles, with the hope of achieving high driving range. Unfortunately, serious side-reaction issues have plagued their development for practical applications so far. For example, during the discharge process, undesired insulating products are formed instead of lithium peroxide. Moreover, the blocking/clogging effect on the air electrode due to a deposition process leads to an overpotential during both the discharge (Oxygen Reduction Reaction: ORR) and charge processes (Oxygen Evolution Reaction: OER), which results in electrode degradation, electrolyte decomposition and precocious cell failure.A promising strategy to reduce these overpotentials is the use of organic redox mediators by taking advantage of their tunability. For several years, our group has been developing lithiated organic materials with average redox potentials close to the O2/Li2O2 redox couple (2.96 V vs Li+/Li0). We here report the effect of Li2DAnT (alone or in combination with Li4-p-DHT [1]) and Li4-DHNDC [2] on the cycling behavior of Li-O2 batteries and their influence on ORR and OER processes. References 1) S. Renault, et al., PCT Patent WO 2021/148835 A1.2) S. Renault, et al., PCT Patent WO 2021/148836 A1. Figure 1