Engineering Intelligent Graphene Oxide‐Cellulose Membranes: Suppressing Thermal Runaway for a Safer Aqueous Zinc‐Ion Batteries

ABSTRACT Intelligent thermal management is essential for battery safety in sustainable development. Herein, we incorporate the “intelligence” property into aqueous zinc‐ion batteries (AZIBs) by introducing a thermo‐responsive graphene oxide/hydroxypropyl cellulose (GO/HPC) composite membrane as a smart thermal protection component. The as‐prepared membrane demonstrates exceptional flexibility and mechanical robustness, with a Young's modulus of 3.3 GPa. Taking advantage of the reversible lower critical solution temperature (LCST)‐driven phase transition of HPC, the membrane undergoes autonomous shrinkage and ionic shutdown when the ambient temperature reaches 65°C‐triggering an immediate self‐protective state to suppress thermal runaway in AZIBs. Mechanistically, the conformational transition of HPC (from hydrophilic extended chains to hydrophobic globules) upon heating simultaneously blocks Zn 2+ transport and water permeation across the membrane, while the amphiphilic GO surface guides the ordering of liquid crystalline HPC domains to optimize this dual‐functional switching behavior. Notably, AZIBs integrated with this intelligent membrane retain 92% and 80% of their initial capacity after a single thermal shutdown‐cooling cycle and after 15 repeated shutdown‐recovery cycles, respectively, confirming the reversibility of the membrane's thermo‐responsive behavior. This work provides a rational material design paradigm for the safety of AZIBs, facilitating their use in practical applications from consumer electronics to large‐scale grid energy storage.