Sharp have announced the development of a prototype direct methanol fuel cell (DMFC) that it claims achieves the world's highest power density. The cell is constructed of a stack of multiple reed-shaped thin cells, sandwiched together with similarly shaped porous spacers. That increases surface area and maximises air-flow (essential for the fuel cell to produce power), resulting in 0.3W/cc power density.
That's actually around seven times greater than previous Sharp technology could manage. The company's stated goal is to produce a DMFC which is the same size as a lithium-ion battery but produces far more power output, ideal for a mobile device. Work so far is presumably the product of Sharp's collaboration with Sandia National Laboratories, announced at the start of 2006; no release date has been suggested for a commercial product.
Multiple other companies are currently working on fuel cells, including Toshiba, Sony and MTI Micro. However while Sony's super-compact cell uses active pumping of methanol, the Sharp cell is passive and thus the densities are not being compared. Both, though, could be "recharged" as simply as slotting in a new cartridge of methanol.
[via PC World]