ONEBAT: Micro-solid oxide fuel cells for battery replacement in portables

The Swiss ONEBAT project aims for the fabrication of micro-solid oxide fuel cells. These are miniaturized solid oxide fuel cells in which the active fuel cell components (anode, electrolyte and cathode) exist as thin films forming a free-standing membrane on a substrate. The total thickness of the fuel cell membrane is less than 2 micrometer in thickness and of 200 micrometer in diameter. Heat cycling between room temperature and 550°C are possible for such membranes without rupture or crack development. The future goal is to integrate these micro-solid oxide fuel cells in a system with reformer, post-combustor and insulation, and to replace current Li-ion batteries. Microstructure and electrical conductivity characteristics of micro-solid oxide fuel cell gadolinia-doped ceria thin film electrolytes are reported in more details in this study.