Abstract
It was found in our previous study that the passive type polymer electrolyte fuel cell (PEFC) with the dead end system, suffused from power breakdown after in a short time the start of the experiment because anode of flooding. In order to overcome this short coming without relying on pumps, the hydrogen circulation system utilizing the pressure difference was developed. The influence of pressure and flow rate was also investigated. The tested PEFC module consisted of 20 cells laid out in plain and they were connected in series. The system was controlled so that the hydrogen pressure in the module was kept between 5kPa and 15kPa with a valve and two check valves. In this system, the valve repeated the ON-OFF operation and produced hydrogen circulating flow and removed the water. This system demonstrated a long time operation more than 6 hours.
