Anode-supported thin electrolytes for operating at intermediate temperature have been successfully manufactured by tape casting and co-firing techniques that could be cost-effective for mass production of solid oxide fuel cell (SOFC) single cells. The characteristics of slurries and green tapes were investigated in order to optimize slurry compositions for thin-tape casting. When the amount of dispersant was 0.8 wt% and the weight ratio of the powder to binder solution was 2.5, the homogeneous microstructure of the green tape was obtained. The anode-supported electrolytes prepared by our process had the excellent microstructural characteristics such as gas permeability, porosity, and sintered microstructure at 1350 degrees C of the co-firing temperature and there were no defects. The power densities were evaluated according to the thickness of the anode-supported electrolyte, and a cell having 5 mu m thickness of the anode-supported electrolyte and anode active layer showed good electrochemical performance (0.55 W cm(-2) at 700 degrees C) at intermediate temperatures. (c) 2008 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.