Nonvolatile and Nonflammable Sulfolane-Based Electrolyte Achieving Effective and Safe Operation of the Li–O<sub>2</sub> Battery in Open O<sub>2</sub> Environment
Zhengang Li, Cun Yi Song, Peng Dai, Xiaohong Wu, Shiyuan Zhou, Yu Qiao, Ling Huang, Shi‐Gang Sun
Abstract
The Li–O2 battery should operate effectively/safely in an open O2 environment for practical applications, but not trapped in sealed/closed atmosphere. However, the typical use of volatile and flammable electrolyte restricts Li–O2 battery to be able to be running in open O2 environment. We report herein, for the first time, a highly electrochemical reversible Li–O2 battery operated in an open O2 environment, i.e., under the condition of keeping O2 flowing continuously based on a nonvolatile and nonflammable sulfolane (TMS) solvent. The electrochemical irreversibility of Li2O2/O2 conversion and incompatibility between Li metal anodes and electrolyte have been addressed via dissolving LiNO3 in concentrated TMS electrolyte. The tuned electrolyte not only enables a stable solid electrolyte interphase (SEI) with conformal inorganic components (including LiF, LiNxOy, and Li2O) that promotes a uniform Li electro-plating/stripping process but also results in a low charge overpotential, a stable discharge terminal plateau, and reversible O2 generation of the Li–O2 battery conducted in an open O2 environment.