Evaluation of flow field design effects on proton exchange membrane fuel cell performance

Abstract

Fluid distribution, conduction, and heat control are important phenomenon in the fuel cell fraternity, therefore it is crucial to develop a state-of-the-art bipolar plate (BP) to attain optimum cell performance. Metal foam (MF) and fine mesh have attracted a lot of attention in mitigating some of the challenges associated with straight, and serpentine channels. In this study, MF, 3D fine mesh, fine wire mesh (FWM) flow fields are compared with triple serpentine flow field to develop an optimum design for improved PEMFC performance. Two different foam designs are studied to attenuate the existing drawback associated with MF, mainly caused by high water retention. The 3D fine mesh is leading in performance under anodic and cathodic stoichiometry of 1 and 3 respectively. On increasing the anodic and cathodic stoichiometry to 1.2 and 3.5 respectively, the FWM took the lead. This is brought by the improved water drainage under high stoichiometry. Because FWM is already in mass production, although for other purposes, it is cost competitive over the other designs. The fine mesh and the MF have the potential to break down large water droplet making them easy to drain. They also showed symmetric fluid flow, compared to the serpentine design.