Influence of the ohmic contact resistance at the interface between Gd-doped CeO2 (GDC) interlayer and scandia-stabilized zirconia (ScSZ) electrolyte on the performance of solid oxide fuel cells (SOFCs) was investigated. When GDC interlayer was used, the ohmic resistance of SOFCs was increased due to insufficient contact conditions between the GDC interlayer and ScSZ electrolyte. To improve the contact conditions, the effect of sintering temperature and sintering aids (Mn, Fe, Bi) on the ohmic contact resistance was evaluated. As a result, using an optimized Mn-modified GDC interlayer (with added 0.3 mol% Mn and sintered at 1300 degrees C) to decrease the ohmic contact resistance, an anode-supported cell with Sr-doped LaFeO3 cathode and ScSZ electrolyte achieved a power density of 1.5 W cm(-2) at 800 degrees C. (c) 2014 Elsevier B.V. All rights reserved.