Study on the performance improvement of polymer electrolyte membrane fuel cell with inclined channel shape

In this study, inclined channel was suggested as a novel cathode flow field for polymer electrolyte membrane fuel cell to improve its performance by reducing concentration losses. The inclined channel has a tapered channel depth which gets narrow from inlet to outlet. Three types of inclined channels which have a different ratio of inlet and outlet depths were applied at the cathode side of fuel cell and the performance was evaluated. As a result, we found that the maximum power of fuel cell could be improved by about 28.7% when we changed conventional straight channel to inclined channel which has the narrowest outlet depth. Furthermore, we verified that concentration losses of fuel cell are reduced with inclined channel, which was investigated by conducting electrochemical impedance spectroscopy method. The numerical analysis was also conducted to explain the factor of performance improvement. Eventually, we verified that inclined channel can promote less-declined air velocity and high oxygen diffusion compared with conventional channel and this effect can make fuel cell performance improved. (C) 2019 Elsevier Ltd. All rights reserved.