Improvement of Protonic Ceramic Fuel Cells with Thin Film BCZY Electrolyte

Abstract

The performance of protonic ceramic fuel cells (PCFCs) using the thin film BaCe0.6Zr0.2Y0.2O3-δ (BCZY622) electrolyte has been studied. The reference cell with the La0.8Sr0.2MnO3-δ cathode and Ni anode showed a poor performance and short-term degradation. The overpotential of the anode and ohmic loss were the major limiting factors for degradation, and a solid solution of Ni in the BCZY electrolyte has been observed. The electrical conductivity and the proton concentration of BCZY and BCZY622 doped with 5wt% NiO were measured by an impedance analysis and thermogravimetric analysis. The electrical conductivity and the proton concentration of BCZY622 decreased by introducing NiO. To avoid a short-term degradation, the cell construction, manufacturing process, and cathode materials were improved. As a result, a carefully designed PCFC with a thin film BCZY622, Ba0.5Sr0.5Co0.8Fe0.2O3-δ 　cathode and Ni/BCZY622 cermet anode showed the good power density of 200-300mW/cm2 in the wide temperature range of 873 - 1073K , and had a stable generation.