Principal Scientist, Masaru Tsuchiya, made this advancement in collaboration with Harvard University researchers, Dr. Bo-Kuai Lai and Professor Shriram Ramanathan.
In a paper published in the April 3, 2011 online issue of Nature Nanotechnology ("Scalable nanostructured membranes for solid-oxide fuel cells"), the researchers presented thermomechanically stable, nanometer scale electrolyte membranes with lateral dimensions on the scale of millimeters to centimeters. A metal grid placed adjacent to the fuel cell provided mechanical stability as well as enhanced electrical conductance. The demonstrated performance includes a power density of over 150 mW/cm2 at 510°C with a platinum-free cathode, and a total power output of over 20mW from a single fuel cell chip, the leading performance among nanometric thin film SOFCs.
The breakthrough has practical relevance for the broad commercialization of fuel cells since thin film SOFC s offer three major advantages over conventional SOFCs:
1. They reduce the amount of materials required in making fuel cells, including rare-earth elements such as yttrium and lanthanum, thus significantly reducing the material cost of SOFCs.
2. The grid's structure reduced the potential of breakage compared to other thin film SOFC.
3. Enhanced conductance across the nanometric thin film electrolytes enables operation at a commercially advantageous temperature of 350-550°C. Conventional SOFC temperatures (600-1,000°C) make them more susceptible to corrosion and requires more materials for insulation.
"Although proof-of-concept nanometric thin film SOFCs operating at 350-550°C have been demonstrated before, their scalability has remained a significant challenge till now. We have successfully demonstrated scalability of nanometer thin film SOFC technology through careful optimization of metallic grid design and oxide deposition parameters," says Dr. Tsuchiya, Principal Scientist at SiEnergy and the lead author of the paper.