Performance of micro-PEM fuel cells with different flow fields

Four designs of flow fields were applied to micro-proton exchange membrane fuel cells (μ-PEMFCs) using microelectromechanical system (MEMS) technology. The flow fields and membrane electrolyte assembly (MEA) of 2.25 cm2 active area were assembled to μ-PEMFCs. Electrochemical behaviors of these μ-PEMFCs were investigated by polarization method at reactants flow rates of 15 ml min−1, 30 ml min−1 and 50 ml min−1, respectively. This study emphasized the effects of different topologies of flow fields on performance of μ-PEMFCs. Results demonstrated that μ-PEMFCs with different flow fields have similar behavior at reactants flow rates of 50 ml min−1. However, at reactants flow rates of 15 ml min−1 and 30 ml min−1, performance of the μ-PEMFC with long and narrow micro-channels rapidly deteriorated due to the flooding in micro-channels. The mixed serpentine design had a good ability to resist the flooding, but it displayed a low maximum power density because of its short effective length of micro-channels. The results in this study suggested that the μ-PEMFC with a mixed multichannel design flow field and long micro-channels yielded the best performance.