Exergoeconomic Assessment of the Ejector-Based Battery Thermal Management System for Electric and Hybrid-Electric Vehicles

Abstract

The battery is a critical component for operating electric and hybrid electric vehicles where temperature control is vital for safe and efficient operation. In this paper, the ejector-based battery thermal management system (BTMS) is analyzed compared to the basic BTMS system from a thermal and exergo-economic perspective. The ejector is added to mix the refrigerant streams from the cabin evaporator and battery chiller, thus delivering the mixture to the compressor with higher pressure to reduce the compression power and improve system performance. The exergo-economic study is carried out for different evaporator, chiller, and condenser temperatures and different battery thermal loads to illustrate the ejector-based system's technical and economic feasibility. Results show an optimal (minimal) total system cost rate of 0.9092 US$/h for the ejector-based system, compared to 1.0222 US$/h for the basic system (11.1% reduction). Based on the applied conditions, the total exergy destruction is found to be 1.596 kW for the ejector-based BTMS and 2.243 kW for the basic BTMS. Furthermore, the total exergy destruction reduction in the ejector-based system is 28.8% compared to the basic system.