Using an AlCl3/Urea Ionic Liquid Analog Electrolyte for Improving the Lifetime of Aluminum-Sulfur Batteries

Abstract

Aluminum-sulfur (Al−S) chemistry is attractive for the development of next-generation rechargeable battery systems. However, only a few reversible Al−S cells have been reported until now. This paper demonstrates that the use of an AlCl3/urea electrolyte in Al−S cells is a promising approach to improve the cycle life and reach a high discharge voltage plateau of ∼1.6–2.0 V. In contrast to the instability of sulfur in the conventional AlCl3/EMIC electrolyte, sulfur is chemically stable in the AlCl3/urea electrolyte, which allows better cell cycling stability. The Al−S cell delivers an initial capacity of ∼700 mAh gs−1 and maintains a capacity of up to ∼500 mAh gs−1 after 100 cycles.