Proton Exchange Membrane (PEM) fuel cells require effective water transport away from the cathode to ensure stable operation. Many existing water management strategies involve active methods, reducing system efficiency by introducing parasitic losses. In the present work, we report on the improved design and fabrication of a passive water management scheme involving UV-catalyzed porous polymer wicks. The design features two connected porous domains consisting of a methacrylate-based transport layer and polyvinyl alcohol storage layer.
In our previous prototype, large water transport lengths (∼12 mm) prevented adequate removal of generated water. The capillary pressure drop across the two porous domains was insufficient to drive a flow rate matched to the rate of generation. Thus, the current design produces a shorter transport distance (∼3 mm) by developing a new vertical design. An independently produced SU-8 photolithographic mold is incorporated to improve the fabrication process.