Importance of Reaction Kinetics and Oxygen Crossover in aprotic Li-O2 Batteries Based on a Dimethyl Sulfoxide Electrolyte.

ChemSusChem

PubMedID: 26249807

Marinaro M, Balasubramanian P, Gucciardi E, Theil S, Jörissen L, Wohlfahrt-Mehrens M. Importance of Reaction Kinetics and Oxygen Crossover in aprotic Li-O2 Batteries Based on a Dimethyl Sulfoxide Electrolyte. ChemSusChem. 2015;.
Although still in their embryonic state, aprotic rechargeable Li-O2 batteries have, theoretically, the capabilities of reaching higher specific energy densities than Li-ion batteries. There are, however, significant drawbacks that must be addressed to allow stable electrochemical performance; these will ultimately be solved by a deeper understanding of the chemical and electrochemical processes occurring during battery operations. We report a study on the electrochemical and chemical stability of Li-O2 batteries comprising Au-coated carbon cathodes, a dimethyl sulfoxide (DMSO)-based electrolyte and Li metal negative electrodes. The use of the aforementioned Au-coated cathodes in combination with a 1?M lithium bis(trifluoromethane)sulfonimide (LiTFSI)-DMSO electrolyte guarantees very good cycling stability (>300 cycles) by minimizing eventual side reactions. The main drawbacks arise from the high reactivity of the Li metal electrode when in contact with the O2 -saturated DMSO-based electrolyte.