Electrolyte design for rechargeable aluminum-ion batteries: Recent advances and challenges

Aluminum-ion batteries (AIBs) are a promising candidate for large-scale energy storage due to the merits of high specific capacity, low cost, light weight, good safety, and natural abundance of aluminum. However, the commercialization of AIBs is confronted with a big challenge of electrolytes. The selection of electrolytes for AIBs is considerably limited, and most of the available options fail to realize the three-electron transfer reactions of Al3+/Al. This review comprehensively examines recent advances in electrolyte design for AIBs to provide a comprehensive understanding of the opportunities and challenges posed by current AIBs. Furthermore, the advantages, limitations, and feasible solutions of each electrolyte are discussed. The perspectives of developing future electrolytes for AIBs are also proposed.