Regresar

Impact of the Temperature on the Proton Conductivity and Power Output of a PEFC Operating at High Current Densities

Abstract:

Polymer Electrolyte Fuel Cells (PEFCs) have great potential as clean energy conversion devices. Therefore, studies are required to increase the understanding of a PEFC at real operating conditions. Two variables that significantly affect the performance are the temperature and the current load. In the present study, a fundamental constitutive part's performance, e.g., the polymeric membrane (PM) Nafion 212, was evaluated by obtaining its proton conductivity. Also, the cell performance is evaluated considering its output power. Tests were performed in a temperature range of 40-90 °C in steps of 5 °C at a constant current of 50 A. The results show a direct correlation between the proton conductivity and the temperature, and for temperatures greater than 85 °C, the proton conductivity has a growth negligible. It was also found that the PEFC output power has an exponential trend with maximum performance at 75 °C with a power of 25.1 W and proton conductivity of 63 mS.cm-1. Besides, an analysis of the internal factors that impact the proton conductivity and the performance is presented. Finally, empirical correlations for proton conductivity and power output as a function of the temperature with an R-squared larger than 0.96 are proposed.