An advanced PVA-based hydrogel flexible electrolyte material with high anti-dehydration and electrochemistry performance

Polyvinyl alcohol (PVA) hydrogel as a hydrogel electrolyte faces issues such as fracture, dehydration, and poor conductivity, limiting its application in flexible zinc-air batteries. To address these, we propose a triethanolamine (TEA)-modified PVA-based hydrogel material (TPVA). TEA promoted formation of a uniform mesoporous structure and enables TPVA hydrogel to exhibit excellent mechanical properties, with an elongation at break (425%) approximately twice that of PVA (230%). Additionally, TPVA material retains excellent hydration after 120 h, demonstrating a significant enhancement in water retention. TPVA-based ZABs achieved a power density of 46.1 mW cm −3 , which is 3.1 times enhancement than that of PVA-based (14.9 mW cm −3 ), and demonstrated significantly extended cycling stability, maintaining stable charge–discharge operation for 35.7 h, outperforming PVA system (11.5 h). Dynamic simulation revealed TEA-PVA interactions, with TPVA showing denser hydrogen bond networks and lower potential energy. This work proposes a promising approach to enhance PVA hydrogel electrolytes for flexible ZABs.