Evaluation of lithium battery thermal management using sealant made of boron nitride and silicone

Abstract

In this study, a battery thermal management (BTM) system immersed in a silicone sealant (SS) is designed for an 18650-type lithium-ion power battery. When compared with a general water-cooled BTM system, the novel BTM system with a simple structure can provide effective heat dissipation and long-term corrosion protection. The thermal performance of the three battery modules prepared using SS packaging are analyzed in detail, including an air-cooled battery module, a pure SS battery module, and an SS/BN module composited with 10 wt% BN (SS/BN). The charge and discharge measurements are carried out under various conditions such as the natural air cooling, forced ventilation cooling, and immersion cooling methods. The experimental results indicate that the immersion SS/BN system can significantly reduce the maximum temperature of the battery module and balance the temperature in the module at different discharge rates. The maximum temperature of the three immersion SS modules is less than 35 °C during the 3C discharge process. Moreover, the temperature difference of the immersion SS/BN module can be maintained within 0.5 °C. This research can provide insights into the design and optimization of BTM systems, especially under water or moisture conditions.