Current density distributions in polymer electrolyte fuel cells: A tool for characterisation of gas distribution in the cell and its state of health

Analysis of gas transport phenomena in a polymer electrolyte fuel cell by electrochemical pressure impedance spectroscopy

“…Experimental work has been carried out in a test bench previously described [5,23]. The fuel cell was a single 100 cm 2 cell (UbzM, Ulm, Germany).…”

Effect of reactant gas flow orientation on the current and temperature distribution in self-heating polymer electrolyte fuel cells

“…For all orientations, the highest local current density is detected in the straight channel containing the cathode inlet, with a larger skew when both reactant inlets are placed in the same lateral plane, as with the cross-flow orientations (2 and 3). This is due to a higher reactant concentration in this region [5,49], which enhances kinetics and increases the local current density [65]. A higher heat generation rate ensues, raising the local temperature, further improving the reaction kinetics and so on.…”

“…Current distribution mapping investigations of PEFCs are abundant in the literature [47,48], but their coupling with internal thermal mapping is deficient. Common observations include a decline in performance downstream in the flow-field attributed to reactant concentration reduction [5,49], reduced local membrane humidity [50] and gas starvation from flooding [51,52], in addition to lower local currents around the 180° bends compared to straight channels due to trapped water [53]. These results are dependent on operating current density, fuel cell design and operational parameters, which vary between applications.…”

Electro-thermal mapping of polymer electrolyte membrane fuel cells with a fractal flow-field

“…Current and temperature mapping have been instrumental for the in situ diagnosis and analysis of various factors that affect the performance of fuel cells, such as water management [17][18][19], reactant concentration and distribution [5,18,20,21], operating conditions [22,23], flow channel configurations [24], thermal management [25][26][27] and cell compression [28,29]. Some of the current distribution measurement techniques include indirect correlations based on local values [30], use of magnetic effects and Hall sensors [31,32], dependent on local potential measurements at the GDL and catalyst layer, and segmented measurement [33].…”