Abstract: Thermal runaway is the ultimate form of battery fault and failure, and it is also a major industry pain point that restricts the large-scale promotion and application of electric vehicles. A comprehensive overview of the different mechanical abuse forms of power batteries and characteristics, mechanisms and prevention technologies of thermal runaway caused by mechanical abuse is given, pointing out the limitations of current research. By summarizing typical vehicle accidents and mechanical prevention technologies, a research idea of reproducing historical operating conditions by real-world vehicle operating data is proposed, and a five-level evolutionary risk assessment model for thermal runaway of power battery of " fault-smoke-leak-fire-explosion" is put forward. This model uses the judgment and identification of critical thresholds of thermal runaway characteristic parameters to predict and give the early warning of mechanical abuse and thermal runaway. Then corresponding measures will be taken to suppress the triggering and spread of thermal runaway based on accident characteristics, which has important guiding significance and promotion application value for new energy vehicle power battery system and vehicle safety design.