Thick (similar to 5 mu m) conducting perovskite LaNiO(3) films were deposited on ferritic stainless steel (SS) by aerosol deposition (AD) for use as an oxidation resistance coating layer in the metallic interconnector of a solid oxide fuel cell (SOFC). The microstructural evolution and electrical resistivity of the LaNiO(3)-coated SS at the SOFC operating temperature (800 degrees C) were examined. The coated oxide layers were fairly dense without pores or cracks, and good adhesion was maintained, even after oxidation at 800 degrees C for 1000 h. The interface oxides formed between LaNiO(3) and SS consisted of Ni and Mn-containing spinel and a Cr-rich oxide layer. The initial area specific resistance (ASR) of the LaNiO(3)-coated SS was 2.68 m center dot cm2, which was increased to 7.34 m center dot cm2 after post heat treatment at 800 degrees C for 1000 h. The ASR of the LaNiO(3)-coated SS was similar to 30% lower than that of the (La(0.8)Sr(0.2))MnO(3)-coated SS post heat treated for the same time. Ni2+ substitution for Mn3+ in the octahedral sites of the spinel structures appears to decrease the resistivity of the interface oxide layer, and increase the long-term stability of the ASR at high temperatures.