David Kirkpatrick

March 15, 2010

Nanotech improving lithium ion batteries

Sounds like an inexpensive and potent improvement in lithium ion batteries.

From the link:

A new high-performance anode structure based on silicon-carbon nanocomposite materials could significantly improve the performance of lithium-ion batteries used in a wide range of applications from hybrid vehicles to portable electronics.

Produced with a “bottom-up” self-assembly technique, the new structure takes advantage of nanotechnology to fine-tune its materials properties, addressing the shortcomings of earlier silicon-based battery anodes. The simple, low-cost  was designed to be easily scaled up and compatible with existing battery manufacturing.

Details of the new self-assembly approach were published online in the journal  on March 14.

This scanning electron micrograph shows carbon-coated silicon nanoparticles on the surface of the composite granules used to form the new anode. Credit: Courtesy of Gleb Yushin

February 8, 2010

Laptops and air travel …

… aren’t good partners, and will soon be even more at odds. Thanks Department of Transportation.

From the link:

Buying your next laptop computer or smartphone online could suddenly get a lot more expensive if a little-known U.S. Department of Transportation proposal to tighten rules around the shipment of small, battery-powered devices by air goes through, says an industry group opposing the move.

Airline passengers would be affected too, as rules banning spare lithium-ion batteries in checked-in luggage would also be extended to alkaline and nickel metal-hydride batteries, argues George Kerchner, executive director of the Washington D.C.-based Portable Rechargeable Battery Association.

“It will be a nightmare for passengers,” Kerchner said.

On January 8, the department’s Pipeline and Hazardous Materials Safety Administration (PHMSA) announced plans to eliminate exceptions on small lithium cells and batteries, defined as less than 100-watt hours in capacity (typical laptop batteries hold 60-80 watt-hours). Small lithium batteries are considered a class 9 hazardous material, a miscellaneous category which includes dry ice and magnetized goods. Batteries under the 100 watt-hour limit had long been exempted from the rules.

March 12, 2009

Nanoball batteries

Via KurzweilAI.net — Very interesting nanotech!

‘Nanoball’ batteries could recharge car in minutes
New Scientist Tech, Mar. 12, 2009

MIT scientists have designed an experimental battery that charges about 100 times as fast as normal lithium ion batteries.

It contains a cathode made up of 50-nanometer-wide nanoballs of lithium iron phosphate. If cellphone batteries can be made using the material, they could charge in 10 seconds; bigger batteries for plug-in hybrid electric cars could charge in just 5 minutes, vs. 8 for existing batteries.

 
Read Original Article>>

February 9, 2009

Nanotech and battery efficiency

The latest news on nanotechnology and lithium-ion batteries.

The release from today:

Batteries get a boost at Rice

Researchers create hybrid nanocables to improve lithium battery technology

Need to store electricity more efficiently? Put it behind bars.

That’s essentially the finding of a team of Rice University researchers who have created hybrid carbon nanotube metal oxide arrays as electrode material that may improve the performance of lithium-ion batteries.

With battery technology high on the list of priorities in a world demanding electric cars and gadgets that last longer between charges, such innovations are key to the future. Electrochemical capacitors and fuel cells would also benefit, the researchers said.

The team from Pulickel Ajayan’s research group published a paper this week describing the proof-of-concept research in which nanotubes are grown to look – and act – like the coaxial conducting lines used in cables. The coax tubes consist of a manganese oxide shell and a highly conductive nanotube core.

“It’s a nice bit of nanoscale engineering,” said Ajayan, Rice’s Benjamin M. and Mary Greenwood Anderson Professor in Mechanical Engineering and Materials Science.

“We’ve put in two materials – the nanotube, which is highly electrically conducting and can also absorb lithium, and the manganese oxide, which has very high capacity but poor electrical conductivity,” said Arava Leela Mohana Reddy, a Rice postdoc researcher. “But when you combine them, you get something interesting.”

That would be the ability to hold a lot of juice and transmit it efficiently. The researchers expect the number of charge/discharge cycles such batteries can handle will be greatly enhanced, even with a larger capacity.

“Although the combination of these materials has been studied as a composite electrode by several research groups, it’s the coaxial cable design of these materials that offers improved performance as electrodes for lithium batteries,” said Ajayan.

“At this point, we’re trying to engineer and modify the structures to get the best performance,” said Manikoth Shaijumon, also a Rice postdoc. The microscopic nanotubes, only a few nanometers across, can be bundled into any number of configurations. Future batteries may be thin and flexible. “And the whole idea can be transferred to a large scale as well. It is very manufacturable,” Shaijumon said.

The hybrid nanocables grown in a Rice-developed process could also eliminate the need for binders, materials used in current batteries that hold the elements together but hinder their conductivity.

 

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The paper was written by Reddy, Shaijumon, doctoral student Sanketh Gowda and Ajayan. It appears in the online version of the American Chemical Society’s Nano Letters.

The project is supported by funding from the Hartley Family Foundation.

The paper can be found online at: http://tinyurl.com/dz7oe8.