Challenges and Strategies on Interphasial Regulation for Aqueous Rechargeable Batteries

The practical application of aqueous rechargeable batteries faces several challenges due to the limited stability window of electrolytes and parasitic side reactions, such as corrosion, passivation, gas evolution, and co‐intercalations. The solid electrolyte interphase (SEI) formed at the electrode/electrolyte interface plays a critical role in determining interfacial properties and battery performance. Efforts are being made to develop effective SEIs, functionalize interphase layers, and explore various aqueous hybrid electrolytes that facilitate SEI formation. This review highlights the role of interphasial structures in aqueous batteries. First, common issues encountered by aqueous batteries and specific characteristics of aqueous lithium‐ion, sodium‐ion, zinc‐ion, and aluminum‐ion batteries are outlined. Then the tactics used to improve cycle stability of aqueous batteries are introduced and compared and the working principles and key parameters from the context of interphasial modification are discussed. Finally, constructive insights and suggestions for developing high‐performance batteries are offered, with a focus on SEI formation and interphase layer design.