Unit cell performance(current density) was investigated as to various conditions. First of all, as increasing the catalyst contents up to 6w/o, the current density was increased, but decreased the utilization ratio of catalyst was. As thickness of electrode increased up to 0.2mm, the current density was increased but O₂ gain was not good. The decrease of cell performance during at least 200hr was mainly due to the exhaustion effect of electrolyte. We anticipated that as the differences of cathodic gas pressure from anodic on increased, the cell performances were to increased unless the exhaustion of electrolyte. Z & parallel-type gas supply method was better one than those of I & cross-type and Z & counter-type.