Fans are used for cooling and feeding oxygen in air-cooling proton exchange membrane fuel cell (PEMFC). For optimal performance

it is essential that the air is distributed as uniformly as possible and supplied sufficiently

which can be adjusted by varying the working distance and voltage of fans

in order to maintain temperature uniform (with the fan working in certain mode). Experiments were carried out for air cooling PEMFC

with the fan system working under the mode of “blowing”

to find the optimal distance. The temperature on the export side of cathode was measured to reflect the heat dissipation by Fluke Ti25 infrared thermal imager. The load box works under constant voltage mode and automatically records output current of stack

to evaluate the output performance. Moreover

an empirical formula is fitted according to the average temperature under different conditions

with working voltage and working distance as independent variables

and average temperature as the dependent variable. The results show that the performance of the stack declines when the fan is at a distance beyond or below the optimal value. At this optimal distance

the distribution of surface temperature is more uniform

the uniformity of unit cell voltage is better

and the required working voltage of fan system is less. This work provides a guideline and serves as a reference to improve the performance of air-cooling PEMFC by increasing the stability and efficiency of the system.