Scalable fabrication process for new structure BaZr0.8Y0.2O3-δ-based protonic ceramic fuel cells

Abstract

Anode-supported thin-film BaZr0.8Y0.2O3-δ (BZY) electrolyte protonic ceramic fuel cells (PCFCs) have demonstrated the potential for commercial application with excellent output performance, fuel flexibility, and durability at 500–600 °C. However, scaling up of BZY-based PCFCs using traditional cell fabrication processes such as tape-casting & co-sintering is still a big challenge because of the large demand of high-quality BZY powder and the high sintering temperature of BZY ceramic. Herein, an integrated BZY electrolyte matrix with porous/dense bilayer structure was fabricated by a scalable process combining tape-casting, hot-pressing, and solid-state reactive sintering. The electrolyte matrix sintered at 1500 °C showed a pure cubic perovskite phase and desired microstructure in which the thickness of the dense electrolyte layer was 74 μm. NiO anode was in-situ generated within the porous electrolyte layer via rapid impregnation process. The NiO impregnation amount influences the output performance of single cell. The cell with the optimal NiO impregnation amount of 20 wt% delivered a maximum power density of 170 mW cm−2 at 600 °C under wet hydrogen and static air operation. It also showed good short-term stability for 20 h with a constant current density of 155 mA cm−2 at 0.70 V.