Abstract
Solid oxygen fuel cell (SOFC) having yttria-stabilized zirconia (YSZ) electrolyte film thickness of 12-3μm, which was grown on the Ni-YSZ cermet substrate using as the fuel electrode by RF magnetron sputtering, has been studied on the operating property until lower temperature of 700°C. A single SOFC having YSZ electrolyte film thickness of 3μm could be well operated at 800°C and that could performed the V-I property of 700mV-300mA/cm2 indicating the development index of the cell. The open circuit voltage (OCV) of the cell gave nearly the same value as the theoretical electromotive force. However, the OCV drop became larger as making thin YSZ film, because the grain boundary and pore were caused in the film in consequence of a surface roughness on the substrate. The voltage drop of the cell was mainly occupied by the resistance loss in YSZ film and its percentage increased as the operating temperature decreased. Moreover, the film conductivity at the operating temperature of 800°C became smaller by two figures than the theoretical conductivity of the bulk electrolyte.
