Experimental Study on Control Factors for a 1kW Airbreathing PEMFC Stack

Abstract:

In an airbreathing proton exchange membrane fuel cell (PEMFC),the air flow effect is different on the strongly coupled temperature and humidity,and uncertain on the stack voltage.To study the stack performance in detail,the inlet hydrogen pressure and the rotation rate of fans are investigated as effect factors,and the orthogonal experiments are carried out at the corresponding working points.The results show that,when the fans rate is above the optimal value,the air takes more water from the cathode away and the membrane becomes dried slowly,and then membrane impedance increases,therefore the stack voltage declines; in the other hand,when the fans rate is below the optimal value,the heat quantity carried out with air is reduced,making the cathode surface temperature higher,the air relative humidity decreases rapidly,and then the membrane dries quickly,therefore the stack voltage drops sharply.Therefore,there is an optimal fans rate value which makes the stack voltage highest at each working point.