Research progress, challenges, and trends of sensing materials for thermal hazard monitoring in lithium-ion batteries: A review

With the widespread application of lithium-ion batteries (LIBs) in electric vehicles, energy storage stations, portable electronic devices, the safety hazards during their service life have attracted extensive social attention. Among these issues, thermal runaway (TR) has become a principal research focus in the field of LIBs. In order to achieve effective early warning of TR, researchers are initially required to analyze the triggering mechanisms and evolutionary paths of TR. Subsequently, the development of sensing materials capable of accurately capturing the early characteristic signals of TR in a targeted manner is essential. Guided by this objective, this review begins with an analysis of the TR behavior of LIBs. Combined with the crucial characteristic signals released in the early stage of TR, it systematically combs the research progress of mainstream monitoring and sensing materials in recent years, while clarifying the core technical challenges currently faced in this field. In addition, this review points out that the in-depth integration of multi-functional integrated sensing technology and intelligent algorithms significantly enhance the accuracy of TR monitoring and the reliability of early warning. Ultimately, this review looks forward to the prospective development trends of sensing materials in response to the practical requirements of TR monitoring for LIBs, such as corrosion resistance, low-power design, and multifunctional integration, so as to provide a reference framework for subsequent research in this field.