Work

Integrated desiccant-coated heat pump for air conditioning and battery thermal management in electric buses

Year: 2025

Type: article

Abstract: This study introduces a desiccant-coated heat pump (DCHP) system integrated with an air conditioning (AC) unit and battery thermal management system (BTMS) for electric buses. Unlike conventional vapor compression heat pumps (VCHPs), the proposed system directly coats desiccant material onto the evaporator and condenser surfaces, enabling independent control of temperature and humidity. Numerical analyses validated by experiments (mean error <15%) demonstrated significant improvements in thermal performance. Under summer conditions, the system achieved a cooling coefficient of performance ([[EQUATION]]) of 5.92—representing a 110% enhancement over VCHP—while providing a moisture removal capacity (MRC) of 10.8 g/kg without requiring a reheating process. In winter, the heating COP ([[EQUATION]]) reached 8.9, a 134% improvement, with a moisture supply capacity (MSC) of 3.6 g/kg, thus maintaining humidity under dry ambient conditions. A parametric study highlighted the sensitivity of system performance to air velocity, half-cycle time, and evaporation/condensation temperatures, identifying optimal operating ranges for practical applications. For battery management, the system maintained cell temperatures below 47 °C under extreme heat and achieved uniform preheating to 0 °C within 730 seconds under extreme cold. These results confirm that the DCHP-based integrated system simultaneously ensures cabin comfort and battery stability, while reducing energy consumption compared to conventional approaches. The findings provide a foundation for advancing high-efficiency, multifunctional thermal management solutions in electric buses, supporting extended driving range, enhanced passenger comfort, and improved reliability in diverse climates.

Source: Case Studies in Thermal Engineering

DOI: 10.1016/j.csite.2025.107451