Biopolymer electrolytes for rechargeable zinc-air batteries: Advancements and challenges

Gel polymer electrolytes (GPEs) have gained significant attention as alternatives to conventional liquid electrolytes in rechargeable zinc-air batteries (ZABs). Biopolymer-based GPEs, derived from sustainable sources, combine the ionic conductivity of liquids with the mechanical stability of solids, addressing key challenges such as zinc dendrite formation, electrolyte leakage, and corrosion. The use of bio-based materials like cellulose, chitosan, and alginate has opened new opportunities to enhance both performance and sustainability. However, challenges remain, including batch-to-batch variability, chemical instability in alkaline media, and the need for effective purification processes. Despite these limitations, biopolymer-based GPEs offer a promising path toward greener, safer, and more durable ZAB systems. This opinion highlights recent advancements, discusses current limitations, and outlines future directions. Further research into material optimization, environmental assessment, and standardized testing is essential to fully realize the potential of biopolymer-based GPEs for scalable energy storage applications.