Design strategy of metal foam flow field and its application in proton exchange membrane fuel cell

Abstract

Metal foam as flow field for proton exchange membrane fuel cell (PEMFC) has demonstrated substantial promise for enhancing the distribution uniformities of reactants and temperature. In different types of PEMFC, however, the influence of metal foam flow field on cell performance is diverse. For liquid-cooled PEMFC, employing metal foam flow field encounters challenges in water removal. For air-cooled PEMFC, employing metal foam can help retain a certain amount of liquid water to avoid membrane dehydration. In an effort to further enhance the cell performance and practical application potential of metal foam in different types of PEMFC, the design strategy for metal foam flow field in PEMFCs is studied through this chapter. Experimental results revealed that for liquid-cooled PEMFC, the cathode side employing metal foam flow field raises the potential for water flooding and instability of operational voltage, which can be addressed through reasonably designing the structural characteristics of metal foam. Furthermore, the thermal management capability of air-cooled PEMFC can be boosted through adopting metal foam flow field, owing to the synergic improvement of forced convective heat transfer of reactant gas and electrochemical performance, which is the main factor of the thermal management improvement at high current.