Crosslinker‐Free Stabilization of Poly(vinyl Alcohol)‐Poly(acrylic Acid) Gel Polymer Electrolytes Using Multifunctional Additives for Rechargeable Zinc–Air Batteries

Gel polymer electrolytes (GPEs) for rechargeable zinc–air batteries (ZABs) are commonly stabilized through chemical crosslinking or thermal treatments, which increase processing complexity and may compromise electrolyte transport. Herein, we demonstrate an alternative stabilization strategy based on hydrogen‐bond engineering through the incorporation of low‐molecular‐weight polyols into poly(vinyl alcohol)–poly(acrylic acid) (PVA–PAA) matrices. Glycerol (G) and ethylene glycol (EG) were incorporated to produce crosslinker‐free GPEs without thermal curing (PP‐G and PP‐EG), which were compared with thermally treated PVA–PAA (PP‐T). PP‐G exhibited a higher degree of local chain ordering, a larger electrostatic potential ( μ = 13.64 D), the highest KOH uptake (1080%), and the highest ionic conductivity (208 mS cm −1 ). Although glycerol reduced the strain at break from 121% (PP‐T) to 82%, the resulting polymer network maintained excellent structural integrity while significantly improving electrochemical performance. Rechargeable ZABs assembled with PP‐G delivered a power density of 54 mW cm −2 , an areal capacity of 10 mAh cm −2 , and stable cycling over 500 charge–discharge cycles (80 h). More importantly, the enhanced electrolyte retention enabled stable battery operation at temperatures up to 85 °C, demonstrating that multifunctional additive‐induced stabilization provides a simple route toward high‐temperature ZABs capable of exploiting low‐grade waste heat.