Strategies for Unlocking Safe and Sustainable Aqueous Sodium‐Ion Batteries

Despite their limited energy density resulting from the narrow electrochemical stability window (ESW) of water, aqueous sodium‐ion batteries (ASIBs) offer a sustainable and accessible alternative for energy storage, particularly suited for stationary energy storage where high energy density is less critical. However, further efforts are still needed to identify compatible materials and to develop strategies for expanding ESW, mitigating active materials dissolution and managing proton cointercalation. This work provides a compressive overview of materials used in ASIBs from the electrolyte to the cathode and anode. It also discusses strategies to mitigate electrolyte‐related drawbacks, while highlighting key advantages such as sustainability, high ionic conductivity, nonflammability and nontoxicity. In addition, other essential materials for components are addressed including current collectors, binders, and separators. Finally, the current status of both scientific and industrial efforts is examined, and future perspectives are also provided.