An experimental study on the enhancement of the water balance, electrochemical reaction and power density of the polymer electrolyte fuel cell by under-rib convection

The flow field design of the uniform distribution of reacting gas generates broad scientific interest, especially among those who study the performances of polymer electrolyte fuel cells (PEFCs). In this study, we find a new serpentine flow field equipped with sub-channels and by-passes to promote under-rib convection. This flow field enables a more effective utilization of the electrocatalysts by increasing the mass transport rates of the reactants from the flow channel to the inner catalyst layer (CL) and by significantly reducing the water flooding at the cathode. This study experimentally evaluates the effect of the new serpentine flow field with sub-channel and by-pass (SFFSB) on the single cell performance and compares it with a conventional advanced serpentine flow field (CASFF). The maximum current and the power densities of the SFFSB are increased by 18.85% and 23.74%, respectively, due to the promotion of under-rib convection.

► This study provides a novel flow field designed to promote under-rib convection.
► We designed a new serpentine flow field with sub-channels and by-passes.
► Under-rib convection improves the electrochemical reaction and water management.
► The new flow field was proven to enhance the power densities.
► These results would help bring success to the set goal of the PEFC performance.