Published on November 25th, 2008 | by Jerry James Stone5
Study Increases Fuel Cell Efficiency By 75%
[social_buttons] According to Physorg.com, a researcher in France has increased the efficiency of micro-sized direct methanol fuel cells to 75-percent. This further paves the way for fuel cells to replace lithium ion batteries in some mobile electronics: I would totally buy a fuel cell powered iPhone!
Fuel cells are seemingly attractive in comparison to lithium ion batteries because of their high energy potential: around sixteen times more energy than lithium ion batteries.
This increase was achieved by injecting a macroporous layer into the silicon-based microfuel cell. It resulted in fuel cells operating at room temperature with a power density of 385 watt-hours per liter. Lithium ion batteries typically have a power density of 270 Wh/L. Oh snap!
Current tech requires an operating temperature of 100 degrees Celsius or higher for fuel cells to actually produce power. Obviously, fuel cells must operate at room temperature before they can be adopted by the consumer market.
In the first study, the fuel cells achieved a power density of 4.3 milliwatts per square centimeter using 1.38 microliters per minute of fuel. But it was the second study that added the macromorphous layer. And it paid off. The density reached 9.25 mW/cm2 when using 550 nanoliters of fuel per minute. Adding fuel boosted power density to 12.7 mW/cm2 but lowered efficiency to 20 percent.
This breakthrough eliminates the need for things like pumps which use fuel to run. But despite this accomplishment, Steve Arscott at the Institute of Electronics, Microelectronics and Nanotechnology in France says many challenges still remain:
“The biggest challenges facing micro fuel cells are: (i) high-performance room-temperature operation, (ii) miniaturization for on-chip use, (iii) compatibility with existing system fabrication (CMOS, for example), (iv) avoidance of complicated pumps for fuel and air which use energy themselves, (v) use of an efficient silicon-based proton exchange membrane and diffusion layers (novel porous layers for example), (vi) full integration with a microchannel architecture and also (vii) fuel storage,” he told PhysOrg.com. “On the latter point, obviously the more fuel efficient the cell, the less fuel needs to be stored for a given working period.”
“One thing is sure,” he added. “Like everyone, I think that energy is about to become very important and, as Mark Twain (of who I’m a big fan) said, ‘What is a government without energy? And what is a man without energy? Nothing, nothing at all…’”