Research on the thermal management system for EREVs utilizing exhaust heat recovery in conjunction with thermal battery technology

This research is focused on improving the cold start efficiency and tackling the reduction in electric-only driving range of extended-range electric vehicles (EREVs) under low-temperature conditions. This is achieved through the introduction of an advanced integrated thermal management system that utilizes exhaust heat recovery and thermal battery technology. The proposed system captures exhaust heat via an exhaust heat recovery heat exchanger (EHRHX) to increase engine temperatures or store the heat in a thermal battery, which is subsequently used to warm the cabin and battery during electric-only driving. Simulation results based on the model developed using AMESim indicate that under engine cold-start conditions at ambient temperatures between −20 °C and 0 °C, preheating with a EHRHX can significantly improve engine fuel economy during the cold-start phase. When combined with thermal battery-assisted preheating, the energy-saving effect becomes even more pronounced. In the cabin and battery heating scenarios during electric-only startup, the use of a thermal battery-assisted positive temperature coefficient (PTC) heating strategy, compared to using the PTC heater alone, not only accelerates the warm-up of the cabin and battery but also maintains PTC energy consumption fluctuations within ±1.4%. Furthermore, under the NEDC standard cycle at −20 °C, the new configuration achieves 3.69% improvement in fuel economy compared to the original configuration.