Numerical investigation of enhanced mass transfer flow field on performance improvement of high-temperature proton exchange membrane fuel cell

The enhanced mass transfer flow fields have been proven to be an effective measure to improve the cell performance of low-temperature proton exchange membrane fuel cells, yet little research has been done for high-temperature proton exchange membrane fuel cells (HT-PEMFC). In this work, three types of cathode-enhanced mass transfer flow fields (tapered, staggered-blocked, and blocked) are designed. The effects of various flow fields on the reactant delivery, current density distribution uniformity, and net power output of HT-PEMFC are quantitatively investigated and compared. It is found that the three enhanced mass transfer flow fields can effectively increase the performance of HT-PEMFC by transforming the traditional diffusion into a combination of diffusion and forced convection. In the sight of the superior performance and lower flow resistance, the tapered flow field is thought to be the optimal candidate for HT-PEMFC among the four flow fields, with a 12.21% net power increment and 5.32% current density distribution uniformity improvement at 1.4 A/cm² compared to the conventional flow field. These results support further performance enhancements and applications of HT-PEMFC.