In planar solid oxide fuel cell (SOFC) stacks ohmic losses are introduced at the interface between the electrodes and current collectors, especially in the cathodic compartments, due to the contact inhomogeneity. The porosity of the electrodes and geometrical issues linked to the shape of the interconnects are factors resulting in the reduction of the contact surface between such components. Contacting layers are often applied between the cathode and the interconnect in order to minimize such issues ensuring a uniform current collection along the electrode area. This leads to proper operation of the cells increasing the performances in terms of power output and mitigating their degradation rate.

In this work, LaNi_0.6Fe_0.4O₃ (LNF) powders have been synthesized by sol-gel methods and used to prepare a contacting paste. A testing setup, developed to test anode-supported cells with different contacting geometries, has been used to investigate the effect of LNF contacting paste between the cathode and the current collector. The cell performances revealed comparable results compared to those measured using a state-of-art La_0.6Sr_0.4Co_0.2Fe_0.8O₃ (LSCF) contacting paste, even showing better stability over time. Cell performances have been investigated by means of current-voltage curves. Electrochemical impedance spectroscopy has been used to distinguish the loss contribution within the investigated system and to measure their evolution over time. To confirm the observed performance evolution, microstructural changes and migration of elements have been characterized post-experiment by means of scanning electron microscopy-energy dispersive X-ray and X-ray diffraction techniques.