Influencing sensitivities of critical operating parameters on PEMFC output performance and gas distribution quality under different electrical load conditions.

• Simulate impacts of operating parameters on PEMFC performance and gas distribution. • Influencing sensitivity of each operating parameter is quantitatively evaluated. • Analyze trends of impact and influencing sensitivity under various loads. • The optimal operating parameters combinations are summarized in this paper. Proton exchange membrane fuel cell has certain requirements on operating conditions. Suitable operating parameters can not only improve the output performance, but also prolong the life duration of fuel cells. Existing studies on the effects of operating parameters on fuel cell performance are often qualitative and lack quantitative indicator of influencing sensitivity. Moreover, there is currently almost no research on impacts of operating parameters on fuel cell internal reactant gas distribution, but local gas starvation caused by uneven gas distribution is one of the crucial reasons for fuel cell lifetime degradation. In this paper, a three-dimensional model of a three-channel serpentine flow field fuel cell is established to study the impacts of seven critical operating parameters on fuel cell output performance and internal gas concentration distribution under different load conditions. By calculating the influential proportion of each operating parameter, its influencing sensitivity on fuel cell performance is quantitatively evaluated. The changing trends of each operating parameter's impact and influencing sensitivity on the output voltage, the mean value and standard deviation of internal gas molar concentration distribution under different load conditions are also analyzed. Besides, the optimal operating parameters combinations at various loads have been summarized based on simulation and calculation results. The research content of this paper can make up for the current vacancy research on impacts of operating parameters on fuel cell internal gas distribution, the quantitative evaluation method of influential sensitivity proposed in this paper can be reference for the operational parameters studies, and the conclusions of this paper can provide more specific guidance for fuel cell performance improvement and control optimization. [ABSTRACT FROM AUTHOR]