Preparation of thin electrolyte film via dry pressing/heating /quenching/calcining for electrolyte-supported SOFCs

Abstract

The development of technologies used to prepare thin electrolyte films will stimulate the application of electrolyte-supported SOFCs since thin electrolyte films typically have low ohmic resistances and good electrochemical performance. This paper presents a novel method for the preparation of thin electrolyte films for yttria-stabilized zirconia (YSZ)-supported solid oxide fuel cells (SOFCs) via dry pressing/heating/quenching/calcining. The thicknesses of the as-prepared YSZ films were as low as 78 μm, which is significantly thinner than those prepared using a traditional method (greater than 200 μm) via dry pressing/calcining/polishing. More importantly, the preparation process was quicker. Using this novel method, a YSZ-supported cell with a configuration of (La0.6Sr0.4)0.9Co0.8Fe0.2O3-δ (LSCF)–Ce0.8Sm0.2O2-δ(SDC)/SDC/YSZ/SDC/Ba0.5Sr0.5Co0.8Fe0.2O3−δ(BSCF)–SDC was fabricated and tested. The results showed promising electrochemical performance and a peak power density of 0.64 W cm−2 at 850 °C was obtained, which was much higher than the cell fabricated using the traditional method (0.29 W cm−2). The ohmic resistance (RO) at 850 °C is 0.19 Ω cm2, which is much lower than that of the cell fabricated using the traditional method (0.33 Ω cm2) at an identical temperature. The modified method described in this work is shown to be a promising technique to prepare thin electrolyte films for high-performance, electrolyte-supported SOFCs.