Published on July 19th, 2010 | by Tina Casey2
Lattice Strain Could Unlock the Door to Cheaper Fuel Cells
July 19th, 2010 by Tina Casey
Lattice strain refers to a slight, atomic-level displacement in the structure of a material, and researchers at The Massachusetts Institute of Technology have just won research funding to investigate how this phenomenon can be harnessed to produce high efficiency fuel cells. The grants came from MIT, the Department of Energy, and the Nuclear Regulatory Commission.
In case you’re wondering why the Nuclear Regulatory Commission is interested, the lattice strain phenomenon could also help boost the performance of the film used in protective claddings at reactors. While nuclear energy is problematic (at best) in terms of true sustainability, as applied to fuel cells the lattice strain research could bring us closer to a cheaper product that is a viable mass-market alternative to gasoline, diesel and other fossil fuels – so thanks, NRC.
Lattice Strain and Fuel Cells
Unlike combustion engines, which burn stuff, fuel cells create an electrochemical reaction to generate electricity from a fuel. One key element is a high efficiency conducting material. The MIT researchers were able to achieve precise control over the lattice strain in a material called yttria-stabilized zirconia (yttrium is a silvery metal), and prove that the new configuration increased the material’s conductivity by almost four orders of magnitude. What is more, the boost in efficiency occurred at the relatively low temperature of 400 degrees K. This could have significant implications for lowering the cost of solid oxide fuel cells, which characteristically require a high operating temperature. Solid oxide fuel cells that can operate at a lower temperature would reduce or practically eliminate the performance and durability issues that currently hinder the technology from moving forward.
Solid Oxide Fuel Cells
A solid oxide fuel cell is characterized by the use of a ceramic electrolyte (an electrolyte is a substance that conducts electricity). Compared to other kinds of fuel cells, solid oxide fuel cells have the potential for high efficiency and stability, and they can use a variety of fuels to achieve the electrochemical reaction that creates usable energy. One recent example is the Bloom Box, which depending on the fuel it uses can create electricity with virtually no carbon emissions. Fuel cells like the Bloom Box demonstrate at least one additional advantage, which is the ability to use reclaimed fuels such as captured landfill gas.
Image: Lattice by fdcomite on flickr.com.