DEVICE AND METHOD FOR JUDGING DETERIORATION IN PERFORMANCE

摘要

An AC impedance meter 200 measures an AC impedance of fuel cells 100 against at least a specific frequency. A sensor group 300 detects at least one operating condition of the fuel cells 100. A detection unit 400 compares a degradation reference value corresponding to the detected operating condition with a resistance value led from the measured AC impedance and detects performance degradation in the fuel cells 100 based on a result of the comparison. This arrangement enables easy detection of performance degradation in the fuel cells, irrespective of a variation in operating condition of the fuel cells.