The study of the effect of gas stoichiometric flow rate on the channel flooding and performance in a transparent fuel cell

This study developed a transparent fuel cell to investigate the water flooding behavior on the cathode channel and analyzed its effect on the cell stability. The transparent cell was fabricated with gold-coated brass plate for the gas channel field and current collected rib. The transparent fuel cell was operated in a steady mode of constant current with the variations of cathode gas flow rate to observe the water flooding behavior in a cathode channel flow. The results revealed that the water flooding increases as the cell operated at a low flow rate and/or low cell temperature. The results indicated that at a high cell voltage (e.g. 0.7 V, electrochemical reaction region), water flooding was observed at low stoichiometric flow rate. At a low cell voltage (e.g. 0.45–0.5 V, 70 A), the performance was dominated by mass transport region. Maximum cell performance was observed at the oxygen stoichiometric flow rate of 6 for the cell temperature of 50∘C and humidified gas of 70∘C. Further increase of stoichiometric flow rate could increase the mass transfer rate, but also result in the drying of the membrane if the stoichiometric flow rate is too high.