Recent Theoretical and Experimental Advancements of Aluminum-Sulfur Batteries

Aluminum-sulfur batteries (AlSBs) exhibit significant potential as energy storage systems due to their notable attributes, including a high energy density, cost-effectiveness, and abundant availability of aluminum and sulfur. In order to commercialize AlSBs, an understanding of their working principles is necessary. In this review, we examine the current advancements in cathodes, both in theory and practice, as well as the progress made in aqueous and nonaqueous electrolytes. We also explore the modifications made to separators and the theoretical understanding of problems associated with AlSBs. Furthermore, we discuss future research directions aimed at resolving these issues. Our aim is to summarize the current progress in AlSBs and, based on recent progress and understanding of the mechanism, help design a battery to overcome the challenges that such batteries have been facing. Aluminum-sulfur batteries have become the most prominent battery technology due to their high theoretical capacity, eco-friendliness, economics, and abundance of aluminum as well as sulfur. Recently, some research work has been done on the various types of carbon used to host sulfur as well as control the aluminum polysulfide shuttling effect. Further, quick progress has been made to find suitable electrolytes theoretically and experimentally, and some success has been achieved with ionic liquid electrolytes. Although these findings are significant, the formation of oxide layers on aluminum, low cyclic stability, and high cost of electrolytes need to be resolved as well to make aluminum-sulfur batteries a competitor to lithium-ion batteries.image