Material Development of Aerogels: Application to Thermal Runaway Protection in Lithium-Ion Batteries

Climate change and global warming, primarily driven by CO₂ emissions from fossil fuel combustion, constitute critical challenges. Alternative energy technologies represent a viable mitigation strategy in which lithium-ion batteries (LIBs) play a vital role, particularly amid the rapid demand for new energy vehicles fueled by policy support, technological innovations, and infrastructure improvements. Owing to their superior properties, including high energy density and long cycle life, LIBs find wide applications; however, safety concerns, particularly thermal runaway, remain significant. Thermal runaway, triggered by mechanical impact, overcharging, or elevated temperatures, frequently causes combustion or explosion, thereby threatening life and property and making thermal runaway suppression essential for LIB safety. Aerogels, characterized by ultra-low density, ultra-low thermal conductivity, and excellent thermal stability, exhibit substantial potential for mitigating thermal runaway because their unique nanoporous structures satisfy the core requirements of thermal runaway protection. This review examines LIB thermal runaway mechanisms, recent thermal protection technologies, and the thermal insulation mechanisms of aerogels for LIB thermal runaway suppression, classifies aerogels used for LIB thermal runaway mitigation, summarizes recent research progress and applications, analyzes key technical bottlenecks, and discusses future development directions, thereby providing a systematic reference for developing high-performance aerogel-based materials that enhance LIB safety.