Applications of Polymers in Zinc Anode Protection for Aqueous Zinc‐Ion Batteries

Against the backdrop of the rapid development of green and sustainable electrochemical energy storage technologies, aqueous zinc‐ion batteries (AZIBs) have attracted significant attention as next‐generation energy storage candidates due to their high theoretical capacity, exceptional safety, cost‐effectiveness, and environmental friendliness. However, Zn anodes suffer from dendrite growth and side reactions such as hydrogen evolution, corrosion, and passivation, leading to low Coulombic efficiency and limited cycle life, hindering the commercialization of AZIBs. Recently, polymer materials have been widely employed to address these issues through the construction of polymer‐based interfacial protective layers or polymer electrolytes, demonstrating broad application prospects. The attractiveness of polymer materials lies in their tunable functional groups, highly designable molecular structures, flexibility, and facile processability. These features allow polymers to shield the Zn anode from direct electrolyte contact, suppressing water‐induced side reactions. Moreover, by homogenizing the interfacial electric field and regulating Zn 2+ transport, polymer‐based components promote uniform and dense Zn deposition, significantly improving cycling stability and reversibility of Zn anodes. This review systematically summarizes recent advances in polymer‐based Zn anode protection strategies, classifying polymers by their functional groups and discussing the design principles, working mechanisms, and optimization approaches of polymer‐based interfacial layers or electrolytes. Finally, forward‐looking perspectives are proposed regarding the key challenges currently faced and future development directions, such as the molecular structure design of high‐performance polymers and the construction of multifunctional synergistic interfaces.