Research Progress of Anode/Electrolyte Interface Modulation for Aqueous Aluminum Metal Batteries

Abstract

Aqueous aluminum metal batteries (AAMBs) have recently emerged as promising candidates for next-generation energy storage systems. Their advantages stem from the abundance and low cost of aluminum, the high theoretical capacity derived from its multielectron redox reaction, and the intrinsic safety of aqueous electrolytes that mitigate flammability risks. Despite these merits, Al3+/Al-based aqueous batteries remain in the early stage of development. Their practical implementation is hindered by persistent challenges in achieving stable electrode-electrolyte interfaces and suppressing parasitic reactions. Specifically, aluminum anodes suffer from spontaneous surface passivation, self-corrosion, and hydrogen evolution in aqueous environments, while aqueous electrolytes generally possess narrow electrochemical stability window (ESW) that promote undesired side reactions and degrade electrode performance. This review systematically summarizes recent progress in modulating the anode/electrolyte interface (AEI) to enhance the electrochemical reversibility and stability of AAMBs. Emphasis is placed on anode design, electrolyte optimization, and the construction of artificial interphases. Finally, the main challenges and future research directions are discussed, offering guidance for the rational design of high-performance AAMBs.