Enhanced Water Management in PEMFCs: Perforated Catalyst Layer and Microporous Layers.

We present an experimental in-situ study to investigate the effects of catalyst layer (CL) and cathode microporous layer (MPL C ) perforation on the water management and performance of polymer electrolyte membrane fuel cells (PEMFCs). Polymeric pore formers were utilized to produce perforated CL and MPL structures. High-resolution neutron tomography was employed to visualize the liquid water content and distribution within different components of the cell under channel and land regions. Our results revealed that at humid conditions, the perforated layers enhanced the liquid water transport under the channel regions. Moreover, at high current densities, the performance was improved for the cells with perforated layers compared to a baseline cell with non-perforated layers, thanks to reduced mass transport losses.