Challenges and design strategies for high performance aqueous zinc ion batteries

Zinc-ion batteries (ZIBs) with near-neutral aqueous electrolytes are considered as competitive systems for large-scale energy storage and wearable electronics applications due to their low cost, high security, desirable specific capacity, and environmental friendliness. However, the sluggish electrode reaction kinetics, poor structural stability, severe Zn dendrite growth, and narrow electrochemical stability window in the entire cell still impede the realization of their full potentials. To address these intrinsic issues in aqueous ZIBs, tremendous efforts have been devoted to boosting their electrochemical properties, such as cycling performance, specific capacity, rate capability, and operating voltage. In this review, we start with the discussion of electrode materials and energy storage mechanisms in aqueous ZIBs. Then specific attention is concentrated on the key issues and recent advances in design strategies for optimizing electrochemical performance in aqueous ZIBs systems. Finally, some potential challenges and future research directions to meet practical applications are also provided.