Effect of contact between electrode and current collector on the performance of solid oxide fuel cells

The effect of contact area between electrode and current collector (i.e., the interconnect) on the performance of anode-supported solid oxide fuel cells (SOFC) has been investigated using current collector with various contact area on the (Pr,Sr)MnO3 (PSM) cathode side. The cell resistance decreased significantly with the increase in the contact area between the PSM cathode and the current collector. When the contact area of the current collector increased from 4.6% to 27.2%, the cell resistance decreased from 1.43 to 0.19 Ω cm2 at 800 °C, a reduction of more than 80%. Furthermore, the polarization losses of the cell were also significantly reduced with the increase in the contact area of the current collector. The results indicate that there is close correlation between the contact area of the current collector and the cell performance. This shows that the constriction effect as frequently observed in solid electrolyte cells not only occurs at the electrode/electrolyte interface but also at the interface of the electrode/current collector. A hypothesis on the effect of the discrete contact between current collector and electrode on the current distribution in the electrolyte cell has been proposed.