“…The energy obtained upon a reaction of H2and O2is directly converted into electric energy. Since a fuel cell has e ciency much higher than that of conventional combustion engines, fuel cell vehicle (FCV) is expected to be a car having high e ciency [1,2]. A polymer electrolyte fuel cell (PEFC) is the prime power source for FCV, as well as another application called a fuel cell uninterrupted power supply (FCUPS).…”