Studies of Degradation from Flooding and Current Distribution in a Self-Draining Channel-less Fuel Cell

The recent wave of interest in sustainability has brought the benefits of fuel cells into the public sphere. Polymer electrolyte membrane fuel cells provide clean and renewable energy, but are subject to degradation. Given the possibilities for use in remote applications, it is necessary to understand and minimize degradation of fuel cell components. Here we analyze common types of degradation resulting from flooding and unusual current distributions in self-draining channel-less fuel cells. Using scanning electron microscopy and energy dispersive x-ray analysis, we show that both flooding and aberrant current distributions do increase the rate of degradation of the membrane electrode assembly. In addition, the current distributions at the anode and cathode are initially equivalent, but anode currents are much more sensitive to small perturbations to the system than the cathode, except in cases of flooding. This suggests that the cathode reaction sites are inherent properties of the membrane electrode assembly structure. If these systems are implemented, the disconnection of a single pillar or equivalent could lead to failure. Furthermore, particular orientations are more susceptible to flooding using this design. If these two characteristics increase degradation rate, improved water removal and stability systems may need to be added to maximize performance of this fuel cell design.