Experimental Study of Three Channel Designs with Model Comparison in a PEM Fuel Cell

The flow field is an integral part of a proton exchange membrane fuel cell. In this work, three flow-field designs, including straight parallel, multiple channel serpentine, and single channel serpentine, are studied systematically to investigate their effects on fuel cell performance. To evaluate the characteristics of each design, relative humidity and flow rate are parametrically adjusted to evaluate performance experimentally. A finite element-based 3D steady state, single phase COMSOL computational model is employed to analyze reactant distribution and fuel cell performance. The single channel serpentine exhibits the best performance under the greatest variety of operating conditions, but also experiences the highest inlet-outlet pressure differentials. This study shows that parallel channel design has more evenly distributed reactant concentration, but is prone to liquid water accumulation, which requires high flow rate to remain stable operation under wet conditions. In summary, the multiple channel serpentine design can provide a reasonable balance between pressure drop and flow distribution with robust fuel cell operation.