Fuel cell, phosphoric acid curves

Figure 17.3.16 Results for oxidation of formic acid (dotted curves) and methanol (solid curves) at a fuel-cell anode (Pt/Ru) with phosphoric-acid-doped polybenzimidazole polymer electrolyte, 170°C. (a) current density and (b) mass signal for CO2 at a scan rate of 1 mV/s. [From M. Weber, J.-T. Wang, S. Wasmus, and R. F. Savinell, J. Electrochem. Soc., 143, L158 (1996), reprinted by permission of the publisher. The Electrochemical Society, Inc.]...

The positive effect of water on the fuel cell performance was further proven by introducing several H2O/H2 mixtures into the anode compartment. I-V curves were recorded for each water vapor partial pressure as shown in Fig. 22. I-V curves were recorded fast, within a time interval less than 30 s, so that the water produced at the cathode would not equilibrate with the membrane. It is evident in Fig. 22 that by increasing the water partial pressure a threefold increase of the cell performance is observ ed, thus proving the vital importance of steam for the efficient operation of the phosphoric acid imbibed high temperature MEA. 

Fig. 3.6 (a) I-V curves for fuel cells based on phosphoric acid-doped PFSA (PA-PFSA) and PBI (PA-PBI) membranes operating with non-humidified hydrogoi and air. (b) schematic illustration of a hydrogen reference electrode allocated on the anode side, (c) Splitting of the PA-PFSA cell performance into cathodic and anodic potentials with help of a hydrogen reference. Reproduced from [101] with permission of Wiley... 

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