A cone-shaped gadolinium doped ceria(Ce0.9Gd0.1O1.95,GDC) electrolyte cylinder with a thin wall was fabricated using slip cast-ing technique.The diameter of the larger open end of the cone-shaped cylinder was 0.85 cm,the length was 1.0 cm,and the thickness of the wall was 0.026 cm after sintering.Both the electrolyte and electrode powders were fabricated by using a glycine-nitrate process.A single solid oxide fuel cell(SOFC) was prepared with the cone-shaped electrolyte,NiO-GDC(70:30 wt.%) anode and Sm0.5Sr0.5CoO3(SSC) cathode.Its electrochemical performance(I-V curve) and electrochemical impedance spectroscopy(EIS) were studied with humidified hydrogen as the fuel and air as the oxidant.The maximum output power density was about 300 ?mW/cm2 at 700 oC.The EIS results showed that the dominant loss of the SOFC was from the ohmic resistance of the electrolyte.