Abstract <p>Metal-air batteries have attracted considerable attention owing to their inherent safety, high energy density, and cost-effectiveness, yet they still face challenges related to electrolyte leakage and corrosion control. While previous research have mainly focused on novel materials and utilization efficiency of batteries, the formation mechanisms and crystalline structures of discharge products remain insufficiently explored. In this work, various polymer gel electrolytes for Al-air batteries were prepared to systematically investigate discharge performance, self-corrosion behaviors, and discharge product formation at the Al anode. Our results reveal that polyacrylic acid (PAA) gel electrolytes uniquely facilitate the crystallization of Gibbsite Al(OH)₃, leading to significantly improved battery performance. Through comprehensive analysis of discharge mechanisms and crystal structures, critical correlations between discharge products and self-corrosion behaviors are detailed illustrated. These findings offer fundamental insights for developing next-generation, corrosion-resistant metal-air batteries with enhanced electrochemical performance.</p> Graphical abstract <p></p>