Durability Study of Anode-Supported SOFC with Large-Area Fabricated By 4-Layer Sequential Co-Lamination and GDC Co-Firing Process

Abstract

Electrolyte-Cathode interfaces are life-threatening regions of solid oxide fuel cells where degradation phenomena occur due to chemical interdiffusion. The Buffer layer is inserted between electrolyte-cathode to limit the cation exchange across the interface. However, state of art buffer layer coated by screen printing does not fully prevent cation migration which results in the formation of insulating phases such as SrZrO3. Herein, a reliable four-layered (NiO-YSZ, NiO-CeScSZ, CeScSZ, and GDC) thin film-based anode supported SOFCs with a large-area (12cm×12cm) were fabricated by sequential co-lamination, in which all cell components perform a distinct role to enhance the interfacial connectivity and packing density of electrolytes. This enhanced connectivity with a highly dense electrolyte (5-6µm) and buffer layer (2-3 µm) accomplished on the porous anode support without any structural defects. The single cell (144cm2) showed a power output of 38W at total current 50A (700°C). The Post-tested cell had exceptional micro-structural characteristics, excellent interfacial adhesion and retained its structural integrity during static and dynamic operation. Also, the formation of insulating phases and decomposition of cathode was effectively prevented, resulting in a remarkable improvement in durability. The cell with four-layered structure exhibits an extreme low-degradation rate of 0.2% kh-1 under 25A current and 21 dynamic load cycling conditions, which satisfies the strict benchmark of durability for commercialization of technology. Key word: Durability, interfacial connectivity, insulating phase, sequential co-lamination Figure 1