Metal Fuels on My Mind | Green Energy News

	The MEET Experimental Metal Air Fuel Cell Make your own power system.

October 31, 2009 – Vol.14 No.32

METAL FUELS ON MY MIND.
by Bruce Mulliken, Green Energy News

I have a bias toward certain energy technologies. Sorry about that, it just happens over time. Among my favorites are metal-air fuel cells and metal-air batteries. Metal-air technology, for now, includes Zinc-air (Zn-air), Magnesium-Air (Mg-air), Aluminum-air (Al-air). Lithium-air (li-air) is apparently possible and one would think many other metals could be used to store and generate electricity when exposed to the stuff we breathe.

The roots of metal-air goes back a century or more – much more – but I won’t get into that in this story.

I like the zinc, magnesium and aluminum in metal-air batteries and fuel cells because, unlike Lithium, all are abundant on the planet, particularly aluminum. (It’s the most abundant metal in the earth’s crust.) All are easily recyclable too. The use of any of those three metals with the “air” technology would allow for unlimited, low-cost energy storage for stationary and mobile applications. The hurdle of energy storage would be leaped.

But that’s just me saying that.

However it’s heartening to see others start thinking more about metal-air. QuantumSphere (QSI), a maker and developer of products which incorporate nanoscale materials, has this to say about metal-air technology:

“Of all available battery chemistries, metal-air batteries such as Zn-air, Mg-air, and Li-air have tremendous potential to deliver breakthrough performance through inherent advantages in both system weight and size. For example, the theoretical energy density of a Zn-air battery (1370 Watt-hours per kilogram (Wh/kg)) is significantly higher than average commercial Li-ion batteries (about 200 Wh/kg). Although previously relegated to hearing aid batteries, recent advances, including those provided by QSI, have enabled new applications for metal-air, such as portable electronic devices and light electric vehicles.”

The company also says in its monthly update that, “Power and capacity demands by next-generation electronic systems exceed the improvement rate of today's battery technologies. Improvements in traditional Li-ion and NiMH batteries have stalled and alternate technologies have not yet provided the performance needed to substitute.”

With that in mind QuantumSphere has developed “a new high performance gas diffusion electrode, incorporating high-surface area manganese catalyst in the 5-30 nanometer size range, for use in metal-air batteries. Depending on conditions and customer specification, the power densities of these new electrodes provide a 40-320% increase in power compared to commercial gas diffusion electrodes, enabling higher discharge rates.”

A gas diffusion electrode is a dual-purpose component of metal-air technology. The “gas diffusion” duty of the component is to allow oxygen to enter the device’s electrolyte to react with another electrode made of a metal, such as zinc, and thus allow for electrons to be available for use. The “electrode” duty is to complete the circuit within the battery or fuel cell and get those electrons flowing to do some real work like powering an electric drive motor to get us to the shopping mall.

(If you’re confused by the term “fuel cell” without hydrogen next to it in the sentence don’t be. “Fuel” when used in conjunction with “cell” actually is a verb. “Fuel” means having the ability to be fueled, or its energy source replenished. “Replenishable-cell” doesn’t have much of a ring to it so “fuel cell” is the popular term.)

Metal-air technology is available now in stores in the form of hearing aid batteries. If you wanted you could buy a zillion of these little things, stack them together and power your house with them. However, if you just want try out a simplified version of metal-air technology contact MEET (Materials for Energy and Environmental Technology) of South Korea. The company has metal-air fuel cells, metal-air batteries, electrode materials and other related products for sale. Overseas shipment is available it seems.

Further, if you’re the inventive type and want to do some experiments in your laboratory, or basement workshop, MEET has an “Experimental Metal Air Fuel Cell” (with “Experimental” meaning the experimenting is up to you.) The company says “Do it Yourself! Make Your Own Power System.” (Use at your own risk by the way.) The Experimental cell operates on Zinc, Magnesium, or Aluminum plates which the company will provide.

Links:

QuantumSphere
http://www.qsinano.com

MEET (Materials for Energy and Environmental Technology
http://www.mee-t.com

Alibaba for MEET products.
http://www.alibaba.com/member/kr100256208/productlist.html

--- Waiting in the Wings: Rechargeable Zinc Batteries.

--- Zinc Air, the Lithium Alternative?