Novel high-performance solid oxide fuel cells with bulk ionic conductance dominated thin-film electrolytes

► Cost-effective wet-chemical method for manufacturing electrolyte for commercial SOFCs. ► Thin electrolyte films were coated on pre-sintered tape-cast anode substrate 7.5 × 7.5 cm2 ► Cells with 1 μm gas-tight electrolytes and 4 × 4 cm2 active cathode area showed high OCV value (∼1.1 V). ► New cells demonstrated significantly higher power output than standard cells and reported data. ► With LSCF and LSC cathodes, the cells yielded 1 A cm−2 and 1.9 A cm−2 (0.7 V, 600 °C, H2), respectively.