Cooling efficiency optimization on air-cooling PEMFC stack with thin vapor chambers

Abstract

• Adjustable VC configuration parameters in the thermodynamic model for VC-PEMFC stack. • Cooling configuration selection considering electrical and thermal characteristics. • The effect of VC configuration parameters on the thermal characteristic is discussed. Proton Exchange Membrane Fuel Cell (PEMFC) stack system generates a lot of waste heat during operation. The integration of Vapor Chambers (VCs) can effectively improve the thermal management, but the cooling methods and VC configurations are to be further discussed. In this study, a lumped parameter model of an open-cathode VC-PEMFC stack system considering the cooling subsystem and variable VC configuration is established and verified. Electrical output performance and thermodynamic characteristics are discussed to evaluate the thermal management. The integration of Vapor Chambers into the PEMFC stack can effectively help reduce the operating temperature but increase the thermal response time. The maximal net power output of VC-PEMFC system is 151.4 W with the coordination of the oxygen fan and the cooling fan. Because of the integration of VCs, PEMFC stack is able to operate at higher current density under the limited operating temperature. Each additional piece of VC can reduce the operating temperature by about 0.9 °C but increases the system weight by 82.7 g. The research results can provide guiding ideas for the design of VC-PEMFC stack system and the development of control strategies.