Current-voltage curve mass transport region

In the current-voltage curve in Fig. 14.15, three different regions can be discerned. At low current densities, the performance is kinetically limited. In the linear part, ohmic losses are significant. At high current densities, mass transport losses dominate. 

Figure 2.5 shows the actual results from a single cell test with a cathode Ft loading of 0.40 mg cm". The OCV was 0.98 V. The resistance of the cell was found to be around 80 mQ cm, measured by the impedance technique at current densities of 0.1 and 0.4 A cm , as shown in Figure 2.6. It is clear from Figure 2.5 that even after the iR correction, the V-1 curve still shows significant voltage decline with increase in the current density, implying that in this iR-dominated region there are still voltage losses due to activation and mass transport.

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