(Digital Presentation) Effect of Compression Pressure on Water Removal and Power Generation Performance of PEFC with Modified Electrode/Channel Structure

Abstract

To prevent the water flooding in polymer electrolyte fuel cells (PEFCs), it is essential to investigate the water transport in cathode diffusion media of operating cells and design the optimum electrode/channel structure for encouraging the water discharge. Our research group has proposed a hybrid structure with the electrode perforation and channel hydrophilization. This study directly visualized the water distribution in the cathode gas diffusion layer (GDL) of a customized PEFC using X-ray radiography and characterized the cell performance under the constant-current operations. Furthermore, the influence of compression pressure on the water behavior in the perforated GDL and the performance characteristics of the customized cell was examined. It was found that the modified electrode/channel structure enhances the water discharge from the diffusion media and effectively reduces the water saturation around the penetration groove. The excessive mechanical compression of the customized cell suppresses the water removal through the diffusion media.