Comprehensive energy, exergo-economic, and exergo-environmental (5E) assessment of a novel electric vehicle battery cooling system layout

With the increasing energy density of batteries in electric vehicles (EVs), the design of battery thermal management systems with high energy performance and reduced economic and environmental costs has become a critical challenge. However, most previous studies have focused mainly on energy or exergy analyses, while comprehensive frameworks simultaneously incorporating economic and environmental aspects remain limited. In this study, a novel integrated thermal management system is developed to simultaneously control the temperature of the battery pack, cabin, and electric motor. The system is evaluated using a comprehensive five-dimensional (5E) framework, including energy, exergy, economic, exergo-economic, and exergo-environmental analyses. A detailed thermodynamic model of the proposed system is developed and validated against experimental data, showing deviations below 6% for key performance indicators. Under baseline operating conditions, the system achieves a coefficient of performance (COP) of 3.81, while the overall exergy efficiency is 5.5%, revealing a significant gap between energy quantity and energy quality. Exergy destruction analysis indicates that the evaporator and condenser are the dominant sources of irreversibility, with the condenser accounting for approximately 80% of the total capital cost. The specific cooling cost is estimated as 0.055 US$/kWh. Parametric analyses demonstrate that optimal thermodynamic and economic performance is obtained at mid-range battery state of charge (SOC ≈ 0.65–0.75). A comparative assessment of alternative refrigerants (R152a, R1234yf, and R513A) shows that R152a provides the highest COP (≈ 4.0), whereas R1234yf offers superior environmental performance due to its ultra-low global warming potential. The results highlight the effectiveness of the proposed 5E framework in identifying dominant inefficiencies and trade-offs, and provide practical guidance for the thermodynamic design, refrigerant selection, and sustainable optimization of next-generation EV thermal management systems.