Innovative Dual Two-Phase Cooling System for Thermal Management of Electric Vehicle Batteries Using Dielectric Fluids and Pulsating Heat Pipes

This study investigates the feasibility of a novel dual two-phase cooling system for thermal management in lithium-ion batteries used in electric vehicles (EVs). The proposed system aims to combine low-boiling dielectric fluid immersion cooling and pulsating heat pipes (PHPs), in order to leverage the advantages of both technologies for efficient heat dissipation in a completely passive configuration. Experimental evaluations conducted under different discharge conditions demonstrate that the system effectively maintains battery temperatures within the optimal range of 20–40◦C, with enhanced temperature uniformity and stability. While the PHP exhibited minimal impact at low power, its role became critical under higher discharge rates, ensuring efficient vapor condensation and pressure stability. The results highlight the potential of this passive cooling system to improve battery performance and safety, supporting its application in EV battery thermal management. Future work aims to optimize design parameters and evaluate real battery modules under ultra-fast charging scenarios.