The high-performance electric sports cars market is expected to register rapid
development in the next years, driven by a different attitude of racing
enthusiasts toward electric vehicles. The improvements in battery technology are
reinforcing consumer confidence and interest in electric sports vehicles, making
them more attractive to enthusiasts and accelerating their adoption. Batteries
have been used in high heat generation conditions more often with fast charging
and discharging. Therefore, the need for more advanced battery thermal
management systems (BTMS) has been increasing in recent years. Vegetable oil,
owing to its unique availability and biodegradability, is considered as a viable
alternative to fossil fuel-based cooling fluids in immersion cooling systems. In
the present work, the feasibility of using vegetable oil in immersion cooling
under high discharge conditions is studied by comparing it with four types of
fossil fuel-based cooling fluids. Immersion cooling was applied to an 8S3P
battery module, and the cooling performance of the battery module at high
discharging rates was studied by using five different types of dielectric
coolants. The immersion cooling model of battery module has been built, and the
cooling performance with different types of coolants at high discharging rates
(4C, 6C, and 8C) has been analyzed. The effect of coolant flow rate on battery
cooling performance was also studied. To make a comprehensive evaluation on the
coolants used for immersion cooling at high discharging rates, an analysis was
conducted by assessing power consumption and temperature uniformity. Cooling
efficiency, power consumption, and temperature uniformity were considered in
coolant selection, and coolant flow rate had a significant effect on coolant
selection. This study can provide a guidance for the design of BTMS with
immersion cooling in electric vehicle applications.