Study of various flow fields in PEMFC by V-i curves, current density distribution and electrochemical impedance spectroscopy measurements

Abstract

On important aspect which determines In the performance of polymer electrolyte fuel cells are the the performance depends on the gas transport processes within the cells. Therefore, the flow field structure has a significant influence on to the performance. In athis study at the German Aerospace Center four principle different flow fields with were investigated in single cells under various operation conditions. The dimensions of the distance between the gas channels and the number of the channels were varied. The different flow fields were investigated by VU-i curves, electrochemical impedance spectroscopy and current density distribution measurements. The paper will present the dependence ies of the cell performance on the flow rates of the reactant gases for various flow fields. The experimental results are compared with simple numerical simulations.