Studies on flooding in PEM fuel cell cathode channels

The main subject of this study are the flooding phenomena in the cathode channels of low-temperature PEM fuel cell. Transparent acrylic materials are used to make various fuel cell models for the experiments. Parameters considered in the experiments include the rate of water injected into the models, the velocity and the temperature of the humidified gas in the cathode channels, the types of flow field, and the temperature of the models. It is found that the parallel and interdigitated flow channels are easily flooded under certain conditions. In order to decrease the chance of flooding, the design of the flow field path should fit the streamline pattern. Furthermore, fuel cells with two different types of flow channels and two different electrode sizes (25, 100 cm2) were made, and their performances were compared to some of the flooding results observed from the transparent physical models.