One‐Step Synthesis of Tough and Superelastic Ceramic Fibrous Sponges for Battery Thermal Runaway Protection

ABSTRACT The escalating risk of thermal runaway propagation poses a major challenge for high‐energy‐density lithium‐ion battery modules. Current passive thermal protection materials struggle to combine robust mechanical resilience with exceptional thermal insulation. Herein, we present a one‐step, dual‐templating electrospinning strategy inspired by the interwoven and curling structure of pumpkin vines to directly synthesize centimeter‐thick, superelastic ceramic fibrous sponges. These sponges, composed of hierarchical micro‐belt and submicro‐fiber assemblies, exhibit outstanding compression resilience (>80%) across a wide temperature range from −196°C to 1100°C, alongside excellent shape adaptability. Their hierarchical porosity yields a low thermal conductivity of 31.98 mW·m − 1 ·K − 1 . Consequently, a mere 3‐mm‐thick sponge layer can effectively quench the thermal runaway propagation in a high‐energy battery module assembled from four 55Ah individual cells, delaying propagation by 729 s—a critical time window for emergency response. This work establishes a new paradigm for fabricating tough, superelastic ceramics, showcasing immense potential for safe battery design and thermal management in extreme environments.