International Journal of Energy Research, Vol.45, No.2, 2474-2487, 2021
Effects of operating parameters and load mode on dynamic cell performance of proton exchange membrane fuel cell
Utilization of fuel cells as a source of driving power would expose them to dynamic variable loading conditions depending on the driving profile and environmental circumstances. The present research study aims to investigate the dynamic behavior of a single-cell proton exchange membrane fuel cell (PEMFC) subjected to various loading modes and operation parameters. A fuel cell with hydrogen gas as fuel has been assembled as the test module. Three different voltage load modes were designed and applied to the cell. The corresponding current variation of the cell as its dynamic response was measured. The dynamic behavior of the cell was examined for various control parameters such as the cell working temperature, inlet humidification temperature, and stoichiometry. The experimental results indicated that the working temperature of 65 degrees C provided the best fuel-cell performance among the three investigated working temperatures of 45 degrees C, 55 degrees C, and 65 degrees C. At different humidification temperatures, the T-a/T-c= 70 degrees C/60 degrees C humidification condition led to the best fuel cell performance due to the adequate wettability of the membrane. However, the humidification temperature might also have induced a minimal impact on the dynamic response of the fuel cell. Although past studies have indicated that higher stoichiometry achieved better cell performance, the experimental data of this study demonstrated that the cell performance of lambda(a)/lambda(c)= 1.5/2.0 was better than lambda(a)/lambda(c)= 1.0/1.0 or 3.0/3.0. The influence of the load modes on the performance of the fuel cell was distinguished when the load was high and driving load changed rapidly. Thus, in the present study, the dynamic behavior of a single cell has been investigated and the outcomes can be directly employed for validation of future theoretical models.