Flame Deposition of the Electrolyte and Cathode for High and Stable Performance of Low-Temperature SOFCs

The key obstacles to the development of low operating temperature (LT) SOFCs are high ohmic resistance and high electrode overpotentials. In the present work, we demonstrate excellent cell performance at 600 °C on a anode supported bi-layer electrolyte SOFC having a thin RSDT-made cerium gadolinium oxide (Gd_0.2Ce_0.8O_2−δ, CGO) and a lanthanum strontium cobaltite (La_0.6Sr_0.4CoO_3−δ, LSC) perovskite cathode. The measured ohmic resistance of the ASE cell with CGO layer deposited by RSDT was 0.24 ohm.cm², which is close to the expected theoretical value of 0.17 ohm.cm² for a 5 micron thick 8YSZ electrolyte at 600 °C. This indicates that the obtained peak power output density is approaching what is theoretically possible. This work is based on the lab scale use of Reactive Spray Deposition Technology (RSDT) which is an open atmosphere, cost efficient technique that does not require high vapor precursors and is an effective way to deposit thin ceramic layers of YSZ/CGO/LSC onto Ni-YSZ substrates. It has the potential to chain successive coating steps thus, significantly simplifying the production of multilayered ceramic structures as the SOFCs and reducing the cost associated with manufacturing of the cells.