Aqueous zinc battery hit 1,000 cycles with plant-derived hydrogel

Researchers at South China University of Technology have developed a sustainable, plant-derived cellulose hydrogel that effectively addresses the dendrite formation problem in aqueous zinc-ion batteries. Zinc dendrites—jagged metallic spikes formed during charging—typically cause internal short circuits and rapid battery failure. The new hydrogel, created by dissolving microcrystalline cellulose and reinforcing it with bamboo-derived TEMPO-oxidized nanofibers, acts as a robust separator that significantly prolongs battery life. These nanofibers serve both as structural reinforcement and as chemical pathways that nearly double zinc ion mobility, resulting in batteries that last 1,100 hours of cycling—far surpassing the 120-hour lifespan of commercial glass-fiber separators. The hydrogel membrane is thin, transparent, and mechanically tough, maintaining smooth zinc surfaces and preventing dendrite growth, which preserves about 80% of battery capacity after 1,000 charge cycles. Made from inexpensive, abundant materials like cellulose powder, bamboo, and borax,