Effect of Dual Porous Layers with Patterned Wettability on Low-Temperature Start Performance of Polymer Electrolyte Membrane Fuel Cell

The low-temperature start problem of polymer electrolyte membrane fuel cells (PEMFCs) is a factor limiting their large-scale application. To improve the low-temperature start performance of a PEMFC, a novel microporous layer (MPL) and a gas diffusion layer (GDL) with planar wettability distribution, in which the hydrophilic and hydrophobic lines were arranged alternately in the in-plane direction, were investigated in this study. The influence of the dual planar-distributed wettability of the MPL and GDL on the normal temperature and low-temperature start performance of the PEMFC was investigated. Before performing the major experiment, the effect of the assembly pressure of the membrane electrode assembly (MEA), which has a significant effect on the PEMFC performance, was examined and determined to use in the experiment. The experimental results show that the dual hybrid MPL and GDL can further prolong the operation time of the PEMFC at different below-freezing temperatures owing to efficient water management and thus significantly improve the low-temperature start performance of the PEMFC.