Processing of high-performance anode-supported planar solid oxide fuel cell

Abstract

Anode-supported planar single cells of dimensions 5 cm × 5 cm × 1.5 mm and 10 cm × 10 cm × 1.5 mm have been successfully fabricated using inexpensive and simple processing techniques. The process involves room temperature lamination of several porous layers of tapecast NiO–YSZ together with a dense layer of YSZ electrolyte followed by cofiring. The half-cell fabrication is optimized while the electrolyte thickness is lowered down from 40 to 10 μm. The fabricated single cells with screen printed La(Sr)MnO 3 (LSM)–YSZ as cathode active layer and LSM as current collector layer shows very high electrochemical performance although no separate active layer is used on the anode side of the fabricated cells. The single cells are tested with hydrogen on the anode and oxygen on the cathode sides. The current density and power density of a typical coupon cell of diameter 16 mm is found to be ≈1.7 A/cm 2 and ≈1.2 W/cm 2, respectively, at a cell voltage of 0.7 V measured at 800 °C. Area specific resistance (ASR) value, evaluated from the current–voltage plot, is as low as 0.205 Ω cm 2 at 800 °C. The performances of these cells are found to be almost size independent having excellent repeatability.