Patent ID: 8822089

Claim:
A method of operating a fuel cell with high power, in which a humidified gas and a dry gas are selectively supplied as oxidant to a cathode of the fuel cell, the method comprising: (S1) supplying the humidified gas while a power is constantly maintained or until the power begins to decrease; (S2) after supplying the humidified gas, supplying the dry gas to obtain a greater power than an average power of the step (S1); and (S3) after obtaining a predetermined power in the step (S2), repeatedly supplying the humidified gas in case the power decreases and supplying the dry gas in case the power decreases again afterwards, thereby increasing the power such that the predetermined power is maintained, wherein the humidified gas is supplied for 20 seconds or less in the step (S3), wherein, the dry gas is supplied for 250 seconds or less in the steps (S2) and (S3), and wherein a power value in the step (S3) is in accordance with the following Math Figure 1: 90% of an average power in the step (S3)≦the power value in the step (S3)≦110% of the average power in the step (S3).