An experimental research on the net output power and current density distribution of PEM fuel cells with trapezoid baffled flow fields

Abstract

The net output power and current density distribution uniformity of proton exchange membrane (PEM) fuel cells are particularly important evaluation criteria in the flow field design. In recent years, the flow field with baffles has become research hotspots, and the trapezoid baffled flow field has been proved to increase the performance of fuel cells. However, most of the research studies only stay at the level of single flow channel simulation and little experimental data on the flow field of the entire bipolar plate. In this study, the performance, pressure drop, and current density distribution of PEM fuel cells with different baffled flow field plates are tested experimentally. The results indicate that adding baffles in the conventional parallel flow field can significantly improve the output performance and current density distribution uniformity of the fuel cell, and the improvement effect is better with the increase in baffle height. However, increasing the baffle height will inevitably raise the pressure drop of the flow field. To solve this problem, the flow field with a half baffle arrangement is innovatively designed. The proposed half-baffled flow field can keep the uniformity of current density distribution and reduce the pressure drop at the same time. This method provides a new inspiration for the design of the flow field.