Sharp and the Massachusetts Institute of Technology this week detailed technology advances in making liquid fuel methanol a source for fuel cells.
Sharp on Thursday claimed to have achieved the highest density ever with its prototype direct methanol to fuel cell (DMFC). The fuel cell has a longer continuous-use life span than a same-size lithium ion battery, Sharp said in a statement.
Sharp will continue to invest in DMFC research and development. It envisions using the technology in consumer electronics such as PDAs and notebook PCs.
Also on Thursday, MIT announced that researchers have managed to improve the power output of a methanol fuel cell by 50 percent. They developed a new technique for creating the membrane material that sits between the anode and cathode ends of a fuel cell.
The material is less expensive than Nafion, which is typically used, and will not absorb as much methanol, making it more efficient, MIT said in a release.
Direct methanol fuel cells are an alternative to using hydrogen as a fuel source for making electricity and have a number of advantages, backers say.
Methanol is "energy-dense," meaning that it holds a lot of energy and, as a liquid, it's easier to transport and store. It's also considered safer than hydrogen, which is combustible. When methanol is fed into a fuel cell, the byproducts are water and carbon dioxide. The carbon dioxide is released in small amounts, according to MIT.
Fuel cell company MTI Micro has DMFCs designed for consumer electronics, includingand . These devices will have replaceable cartridges filled with methanol.
Sharp's research focused on structuring a fuel cell to improve the power output, compared to existing DMFCs. From its statement:
Sharp has developed the three-dimensional highly integrated stack structure through the use of thin cells made by microfabrication. This structure can be created by the alternate lamination of reed-shaped thin cells arranged in parallel at fixed intervals and reed-shaped (porous) spacers, with the cells and spacers running perpendicular to each other like a grid.
With this structure, uniform and continuous spaces are secured, making it possible to increase the cell surface area per unit volume and smoothly circulate the air that is one of the sources for power generation.
The result is a power density of .3 watts per cc, which is about 7 times more than Sharp's previous technology. Sharp said the cell volume can be shrunk further, giving the fuel cells a longer lifetime.