Wednesday, August 16, 2006

Nano Power

If you read the Meow at all, you know I'm completely enamored with all things nano: carbon nanotubes, nanoparticles, nanobots, nanotech. There's just something magical about them. These incredibly tiny workhorses (the width of a few atoms) do such an amazing array of things. Carbon nanotubes can deliver minuscule amounts of cancer fighting chemo medicine to exactly the spot where cancer lies in the body. They're working on nanobots that will act as an in-body monitoring system to diagnose and display individual health stats through the equivalent of "arm TV." Nanotubes can regrow bone, and reconnect severed nerves, and let's not forget that they are the miracle on which we're pinning our hopes for a space elevator. There are more applications of nanotech than I can even begin to list, and more being thought up every day.

A comment on the "Cool and Interesting" post from yesterday brought up another nano miracle; a nanofiber battery, which doesn't use chemicals to store and release energy. No using chemicals hopefully means less pollution, eh? This got my curiosity up and led me to do a little research this morning, and guess what I found? Nanotech earns another blue ribbon at the "cool and interesting" fair. According to Massachusetts Institute of Technology's News Office, researchers at MIT are charging ahead (pardon the pun) with work on this battery breakthrough:

Work at MIT's Laboratory for Electromagnetic and Electronic Systems (LEES) holds out the promise of the first technologically significant and economically viable alternative to conventional batteries in more than 200 years.

Joel E. Schindall, the Bernard Gordon Professor of Electrical Engineering and Computer Science (EECS) and associate director of the Laboratory for Electromagnetic and Electronic Systems; John G. Kassakian, EECS professor and director of LEES; and Ph.D. candidate Riccardo Signorelli are using nanotube structures to improve on an energy storage device called an ultracapacitor.

Capacitors store energy as an electrical field, making them more efficient than standard batteries, which get their energy from chemical reactions. Ultracapacitors are capacitor-based storage cells that provide quick, massive bursts of instant energy. They are sometimes used in fuel-cell vehicles to provide an extra burst for accelerating into traffic and climbing hills.

However, ultracapacitors need to be much larger than batteries to hold the same charge.

The LEES invention would increase the storage capacity of existing commercial ultracapacitors by storing electrical fields at the atomic level.

Okay, quick and easy: Ultra capacitors have some advantages and disadvantages over regular batteries. They have "--a 10-year-plus lifetime, indifference to temperature change, high immunity to shock and vibration and high charging and discharging efficiency." Those are the advantages. However, they traditionally also have " energy storage capacity around 25 times less than a similarly sized lithium-ion battery." This makes them pretty impractical for putting in your portable radio. MIT's article goes into the particulars of why the ultracapacitors have to be so big, but suffice it to say that the materials used before now made them too big to be practical for cell phones and iPods. Enter the nanotubes--nanotubes are minuscule, and very organized. They conduct electricity extremely well. Aligning them in the ultracapacitors gives the battery a whole lot more surface area, which means they can hold a whole lot more energy. The nanotube ultracapacitors can be made in all the battery sizes we have now. All of this sums up to a best of both worlds scenario. What's on the horizon is a small "battery", that's based on electrical fields rather than chemicals, is durable, works in heat or cold, has more power than your lithium-ion rechargeables, and lasts for ten years.

Nanotubes are so cool.

p.s. Thanks Sioux Lady!!