Effects of channel-land configuration on temperature-driven water transport in cathode gas diffusion layer of PEMFC

Effects of the channel-land configuration (CLC) on the temperature-driven (TD) flow have been seldom examined. In this work, a 2-D, non-isothermal, two-phase model incorporating an agglomerate sub-model is established, considering the compression effect and gas diffusion layer (GDL) anisotropy. Results show that the TD flow flux of the through-plane (TP) direction, JTD,TP, is much higher than that of the in-plane direction (JTD,IP) by an order of magnitude. The TD flow is mainly one-dimensional along the TP direction. There are significant differences in the TD flow between the channel and land region. Besides, JTD,TP at the junction of the land region and channel region shows step changes due to the compression effect. After the current loading, the output voltage experiences an undershoot and then undergoes a slow rising and gradual falling process until remaining stable. It is found that the membrane water directly affects the dynamic behaviors of the output voltage. Increasing the inlet relative humidity helps to improve the dynamic response characteristic. JTD,TP also reveals an increasing trend with time after current step loading, contributing to the transition from membrane water to water vapor. This work aims to provide valuable references for better CLC design and satisfactory water management.