Restraining thermal runaway in lithium-ion batteries: A computational model using mini-channel flow boiling for enhanced safety

Abstract

To ensure the stable and safe operation of the battery and prevent large-scale battery packs from thermal runaway (TR) and explosion accidents, it is of great practical significance to investigate lithium-ion battery thermal safety. In the current research, a computationally efficient model for restraining battery thermal runaway was established by Matlab/Simulink. The model was based on the TR chain reaction affected by temperature and was validated with experimental results. The external short circuit process was characterized by a high rate discharge of 12 C. It was found that there was an obvious difference in internal heat generation during battery TR development. The heat generation between the anode and electrolyte accounted for 26.7 % of the total heat generation, which was the main reason for the development of TR. Meanwhile, a new method for restraining the TR by flow boiling of refrigerant R134a in the cooling plate and restraining the thermal spread by thermal insulation layers was explored. The influence of the parameters of the thermal insulation layers between batteries was discussed. Choosing the material with lower thermal conductivity could help reduce the thickness of the thermal insulation and allow the battery pack to be compact and lightweight. Furthermore, the temperature variation of the core and surface of battery under different mass flow rates and convective heat transfer areas were explored. This work gave new ideas to the collaborative suppression of thermal runaway by heat dissipation and thermal insulation, and was conducive to the long-term safe operation of lithium-ion batteries and significantly reduced the safety risk in engineering applications.