3D hybrid-wettability fin channel with dual enhancement of drainage and mass transfer to improve PEMFC performance

The flow field of bipolar plate is crucial for improving the performance of proton exchange membrane fuel cell (PEMFC). In this work, a 3D hybrid-wettability fin channel (HFC) has been designed to enable active drainage and efficient mass transfer. Three key structural parameters of the fins, i.e. tilted angle, wedge width and fin spacing, have been optimized after examining their effects on drainage and mass transfer by simulation. The obtained optimal HFC improved the drainage distance, drainage rate, average oxygen mass fraction and net power density by 72.49 %, 536.94 %, 11.51 %, and 1.73 %, respectively, compared to those of conventional channel. Subsequently, the design of HFC was applied to parallel and serpentine flow fields to verify the benefits of active drainage and efficient mass transfer in cathode-visualized single PEMFC cells. The experimental results show that the peak power densities of parallel and serpentine flow fields with hybrid-wettability fins are 15.56 % and 7.94 % higher than those of corresponding ones without hybrid-wettability fins. The hybrid-wettability fins can also significantly improve the water management of flow fields. Therefore, the HFC design presented herein provides an excellent solution for designing novel flow fields to enhance both drainage and mass transfer performance in PEMFC.