Experimental Study on Improvement of Performance by Wave Form Cathode Channels in a PEM Fuel Cell

We propose a wave-like design on the surface of cathode channels (wave form cathode channels) to improve oxidant delivery to gas diffusion layers (GDLs). We performed experiments using proton-exchange membrane fuel cells (PEMFCs) combined with wave form surface design on cathodes. We varied the factors of the distance between wave-bumps (the adhesive distance, AD), and the size of the wave-bumps (the expansion ratio, ER). The ADs are three, four, and five times the size of the half-circle bump's radius, and the ERs are two-thirds, one-half, and one-third of the channel's height. We evaluated the performances of the fuel cells, and compared the current-voltage (I-V) relations. For comparison, we prepared PEMFCs with conventional flat-surfaced oxygen channels. Our aim in this work is to identify fuel cell operation by modifying the surface design of channels, and ultimately to find the optimal design of cathode channels that will maximize fuel cell performance.