Industrial-sized Warpage-Free Inert Ceramic Supported FT-SIS-SOFCs: Electrolyte Densification Strategy Based on Controlled YSZ Shrinkage

Inert ceramic-supported solid oxide fuel cells (SOFCs) are critical for advancing long-life, high-stability SOFC energy systems. Using an MgO-MgAl 2 O 4 (MMA) substrate, we developed the high-performance industrial-sized MMA-supported flat-tubular segmented-in-series SOFCs (FT-SIS-SOFCs) through a co-sintering process. Dense electrolytes were obtained by implementing bimodal particle engineering to regulate sintering shrinkage behavior. Through precise control of the nanoparticle (∼100 nm) to submicron particle (∼300 nm) mass ratio at 7 : 3, the sintering shrinkage mismatch between the YSZ electrolyte and MMA substrate was reduced from 6.2% to 0.5%, and the warpage deformation decreased from a compressive strain of -0.113 to less than 0.05. The optimized cell demonstrated a maximum power density of 342 mW/cm 2 with an open-circuit voltage of 1.006 V at 850 °C, coupled with exceptional long-term stability. The industrial-sized warpage-free 16-cell FT-SIS-SOFCs exhibited a high open-circuit voltage of 17.50 V and maximum power output of 6.55 W at 850 °C.