A refrigerant-injection heat pump-based efficient integrated thermal management system for electric vehicles approaching the wide temperature range in China

•The wide temperature range is defined for the integrated thermal management system.•The thermal management process of electrical systems is analyzed theoretically.•The multi-mode flow path based on a refrigeration injection heat pump is proposed.•Experimental and simulation results verify the efficient performance of the system.•The system covers the wide temperature range for electric vehicles in China. The integrated thermal management system of electric vehicles is responsible for the temperature regulation of the cabin and electrical system. The wide temperature range of vehicles specifies the operating conditions required for different regions, which is −33 – 39 °C in China. Through experimental studies conducted on heat pump systems and thermal analyses of electrical systems, this study innovatively developed an efficient integrated thermal management system based on a refrigerant-injection heat pump. In addition, a simulation platform for the system was established using the advanced modeling environment for performing simulation of engineering systems (AMESim) software to evaluate the system performance. The results showed that the stability and efficiency of battery cooling based on the intermediate heat exchanger were better than those obtained with a dual evaporator setup. The proposed solution could reduce energy consumption by 30% at an ambient temperature of 35 ℃. The thermal management system with the heat recovery for the motor and electric control at high temperatures could reduce the energy consumption by 11.98% – 56.69% and meet the heating condition of −22.04 ℃. The integrated thermal management system based on a refrigerant injection heat pump widened the operating range during the highway fuel economy test (EPA-420-B-12-001). Aided by electric heating, the simulation system developed in this study could satisfy the load requirements for the wide temperature range in China.