Influence of the phosphoric acid-doping level in a polybenzimidazole membrane on the cell performance of high-temperature proton exchange membrane fuel cells

Enhanced performance of polybenzimidazole-based high temperature proton exchange membrane fuel cell with gas diffusion electrodes prepared by automatic catalyst spraying under irradiation technique

“…In the case of the high temperature PEMFC, phosphoric acid soaked into the porous structure is assumed to play a key role in the proton conductivity of the CL [37].…”

“…Although it is found that the dependence of cell performance on PA content in the anode is not as pronounced as for the cathode [12,35], but the general tendency that excess-or insufficient PA content in the electrodes causes the performance degradation does apply to the anode. Furthermore, there exists a dynamic exchange of PA be-tween the membrane and the CLs [35,37] when the MEA is operated. For these reasons, we simply impregnated both GDEs for the cathode and the anode with same amount of PA, to find out the optimal value for the whole MEA performance, as shown in Fig.…”

In-Situ Dynamic Characterization of Energy Storage and Conversion Systems

“…It usually appears as the largest semi-circle in Nyquist plot and spans from 100 Hz to 1 Hz [68,78,79,[81][82][83][84]. A consistent interpretation proposed for this arc were widely accepted in published cases that an activation process related to ORR contributed to this polarization loss.…”

“…And generally it is quite a small semi-circle comparing to the following impedance arcs. It dominates the region of frequency from above 100 Hz up to 1000 Hz [68,78,79,[81][82][83][84], or even higher. The effects of temperature [79,82] and current density [81,82] on this impedance arc are observable but not as significant as on other impedance arcs dominating lower frequency regions.…”

“…Generally, it dominates frequency region below 1 Hz down to around 0.1 Hz [68,78,79,[81][82][83][84]. The impedance of this arc strongly depends on the compositions of cathode inlet gas, generally consisting of air, oxygen, or a mixture of them.…”