Abstract: The rapid development of flexible wearable electronics has imposed comprehensive requirements on energy storage devices, including safety, thinness, stretchability, and high reliability. Traditional lithium batteries suffer from issues such as flammability, high cost, and insufficient flexibility. In contrast, flexible aqueous zinc batteries are regarded as an important alternative due to the abundance of zinc resources, moderate operating voltage, environmental friendliness, and high safety. However, their performance is limited by bottlenecks such as slow ion transport in the electrolyte, poor interfacial stability, and the tendency for zinc dendrite growth. PVA/PAA/PAM-based hydrogel electrolytes, with advantages such as film-forming ability, adhesiveness, water retention, and strong designability, provide a new approach for regulating Zn2+ migration and suppressing dendrite growth, and thus have become a current research hotspot. Flexible aqueous zinc-ion batteries are considered promising energy storage devices for wearable and portable electronics because of their intrinsic safety, low cost, and environmental compatibility. However, practical deployment remains hindered by sluggish ion transport in hydrogel electrolytes, unstable electrode/electrolyte interfaces, limited mechanical robustness, and severe zinc dendrite growth during repeated cycling. This study focuses on polyvinyl alcohol/polyacrylic acid/polyacrylamide (PVA/PAA/PAM)-based hydrogel electrolytes and systematically analyzes the structural basis and synergistic regulation mechanisms that enable improved ionic conduction and dendrite suppression. By integrating complementary molecular interactions, the composite hydrogel can construct continuous ion-conduction pathways, reduce the activation energy for ion migration, and regulate the Zn2+ solvation structure through reversible coordination with polar groups. In addition, crosslinking engineering, double-network or interpenetrating-network design, …
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