Innovative solid carbonate¯ceria composite electrolyte fuel cells

An innovative solid carbonate¯oxide composite and related fuel cell (FC) technology is reported. It was discovered that solid carbonate¯ceria composite (SCC) electrolytes were highly conductive with the material conductivity level varying from 0.001 to 0.2 Scm-1 between 400 and 600 °C, and related FCs reached a power density between 200 and 600 mWcm-2 at a current density of 300¯1200 mAcm-2 in the same temperature region. The SCCs were discovered to possess both oxide-ion (originating from the ceria phase) and proton (from the carbonate phase) conduction. Being an all-solid ceramic FC, the SCC can effectively reduce the material corrosion problem that is serious for the molten carbonate fuel cells (MCFCs). On the other hand, the innovative FC technology based on the SCC electrolytes developed in this work is similar to solid oxide fuel cells (SOFCs) and different from the MCFCs based on their ionic transport and FC processes, which facilitates a development of new type of advanced FC technology.