Tubular solid oxide fuel cells fabricated by slip-phase inversion combined with a vacuum-assisted coating technique

Abstract

Anode-supported tubular solid oxide fuel cells with diameters of ~4mm based on yttria-stabilized zirconia (YSZ) electrolytes were fabricated by slip-phase inversion combined with a vacuum-assisted coating technique. NiO–YSZ anode tubes were prepared by slip-phase inversion and the YSZ electrolyte membranes were prepared on the NiO–YSZ anodes by the vacuum-assisted coating method. The effect of pre-sintering treatment of anodes on the densification of the supported electrolytes was studied. Dense electrolyte membranes were obtained based on the anodes which were pre-sintered at 1000°C with the co-sintering temperature of 1400°C. Furthermore, an anode functional layer between anode and electrolyte was also fabricated by the vacuum-assisted coating method to enhance the performance of the cell. With La0.8Sr0.2MnO3−δ–YSZ (LSM–YSZ) as the composite cathode, a maximum power density of 178mWcm−2 was obtained at 700°C for the single cell with an anode functional layer and a 22-µm-thick YSZ electrolyte. Resistances of the tested cells were investigated under open circuit conditions at different operating temperatures by impedance spectroscopy.