Performance research of integrated thermal management system for battery electric vehicles with motor waste heat recovery

In this paper, an innovative integrated thermal management system (ITMS) for battery electric vehicles (BEV) with waste heat recovery (WHR) system is proposed. To achieve a low-temperature environment, the proposed system aims to reduce the energy consumption of the thermal management system (TMS) and extend the driving range of battery electric vehicles. The study showed that after adding the waste heat recovery system, not only can the temperature of the motor and motor controller be effectively reduced, but also using the waste heat to heat the cabin and battery can effectively reduce the TMS heating energy consumption. In addition, the heat pump air conditioning system (HPACS) in a low-temperature environment is not the ideal heating problem, introducing a high-efficiency zone for the heat pump (HP) heating can reduce the energy consumption of the HPACS. The results showed that by adding the WHRS at −5 °C, −15 °C and −25 °C, the time for the cabin to reach the target temperature was reduced by 11 s, 20 s, and 122 s, the cabin PTC energy consumption was reduced by 68.7 %, 49.98 % and 35.97 % and the battery PTC energy consumption was reduced by 17.56 %, 9.14 % and 15.30 %. The average temperature of the motor and motor controller declined by about 30 °C and 18 °C. Compressor energy consumption was reduced by 14.68 %, 17.41 % and 16.27 %. Battery SOC increased by 0.651, 0.650 and 0.631. The driving range of BEV increased by 8.58 km, 6.67 km and 5.05 km. To a certain extent, it solves the problem of reducing the range of BEV due to the high energy consumption of TMS in a low-temperature environment.