Experimental study on the effect of thermal radiation on the performance and temperature of PEM electrolyzer stacks

Abstract

The thermal runaway and membrane degradation of proton exchange membrane (PEM) electrolyzer stacks may be induced by the thermal radiation. The effect of thermal radiation on both the performance characteristics and temperature distribution of the PEM electrolyzer stack is experimentally investigated using the constant current method. The performance evaluation and optimization strategies for stacks under the extreme thermal radiation are clarified. The results indicate that the drop in stack voltage is induced by the loading of thermal radiation. At a heat flux of 6.2 kW/m², the maximum voltage drop ratio reaches 5.56 %. The average conductivity of the thermal radiation group is 0.24 µS/cm higher than that of the control group at a water flow rate of 60 mL/min. Thus, the thermal radiation is found to accelerate the degradation of the PEM. In the water starvation test, the voltage runaway of the stack is aggravated by the thermal radiation, resulting in the fifth cell voltage reaching 8.91 V. Moreover, an increase in the water flow rate or the loading of a wind field can be effective measures to improve the temperature uniformity. However, when the inlet water temperature exceeds 50 ℃, the improvement effect of the wind field is limited.