Development of a performance test method for PEFC stack

It is important to obtain repeatable I–V characteristics in order to evaluate the steady-state performance of a PEFC stack. A performance test method would be useful for this purpose; so, we conducted experiments with several PEFC stacks to collect data. In this study, we set two goals. One was to stabilize the PEFC stack output, and the other was to clarify the operating conditions and to determine the accuracy required to control the parameters that affect the I–V characteristic curve, including stack-operating temperature (coolant outlet temperature), gas operating pressure, gas utilization ratio (gas stoichiometry) and gas dew point. Through experiments, we found a means of obtaining repeatable data with a stack voltage accuracy of ±1%.