Building robust anode-electrolyte interfaces for durable and efficient aqueous Al-ion batteries

Aqueous aluminum-ion batteries (AAIBs) are emerging as promising candidates for large-scale energy storage, offering advantages in resource abundance, high theoretical capacity, and operational safety. This review offers a detailed analysis of the synergistic optimization between anode materials and electrolyte systems, with special focus on the crucial role of the anode-electrolyte interface (AEI) in determining the cycling stability and overall performance of AAIBs. The challenges associated with AEI stability are examined by systematically reviewing recent advancements in AAIB anode materials. Design strategies across different material categories and their interactions with electrolytes are evaluated to improve the electrochemical performance of the AEI. Additionally, we examine the latest electrolyte modification techniques, proposing new optimization pathways for electrolyte composition that can further enhance AEI performance. By comparing Al-based and non-Al anode materials, we highlight their distinct behaviors and discuss potential multidimensional development pathways for both anode materials and AEI. This review provides an in-depth understanding of AAIB energy storage mechanisms and highlights AEI optimization as the essential bridge between fundamental electrochemistry and high-performance devices.