Posted on 12/19/2007 5:29:22 PM PST by decimon
Stanford researchers have found a way to use silicon nanowires to reinvent the rechargeable lithium-ion batteries that power laptops, iPods, video cameras, cell phones, and countless other devices.
The new version, developed through research led by Yi Cui, assistant professor of materials science and engineering, produces 10 times the amount of electricity of existing lithium-ion, known as Li-ion, batteries. A laptop that now runs on battery for two hours could operate for 20 hours, a boon to ocean-hopping business travelers.
"It's not a small improvement," Cui said. "It's a revolutionary development."
The breakthrough is described in a paper, "High-performance lithium battery anodes using silicon nanowires," published online Dec. 16 in Nature Nanotechnology, written by Cui, his graduate chemistry student Candace Chan and five others.
The greatly expanded storage capacity could make Li-ion batteries attractive to electric car manufacturers. Cui suggested that they could also be used in homes or offices to store electricity generated by rooftop solar panels.
"Given the mature infrastructure behind silicon, this new technology can be pushed to real life quickly," Cui said.
The electrical storage capacity of a Li-ion battery is limited by how much lithium can be held in the battery's anode, which is typically made of carbon. Silicon has a much higher capacity than carbon, but also has a drawback.
Silicon placed in a battery swells as it absorbs positively charged lithium atoms during charging, then shrinks during use (i.e., when playing your iPod) as the lithium is drawn out of the silicon. This expand/shrink cycle typically causes the silicon (often in the form of particles or a thin film) to pulverize, degrading the performance of the battery.
Cui's battery gets around this problem with nanotechnology. The lithium is stored in a forest of tiny silicon nanowires, each with a diameter one-thousandth the thickness of a sheet of paper. The nanowires inflate four times their normal size as they soak up lithium. But, unlike other silicon shapes, they do not fracture.
Research on silicon in batteries began three decades ago. Chan explained: "The people kind of gave up on it because the capacity wasn't high enough and the cycle life wasn't good enough. And it was just because of the shape they were using. It was just too big, and they couldn't undergo the volume changes."
Then, along came silicon nanowires. "We just kind of put them together," Chan said.
For their experiments, Chan grew the nanowires on a stainless steel substrate, providing an excellent electrical connection. "It was a fantastic moment when Candace told me it was working," Cui said.
Cui said that a patent application has been filed. He is considering formation of a company or an agreement with a battery manufacturer. Manufacturing the nanowire batteries would require "one or two different steps, but the process can certainly be scaled up," he added. "It's a well understood process."
Also contributing to the paper in Nature Nanotechnology were Halin Peng and Robert A. Huggins of Materials Science and Engineering at Stanford, Gao Liu of Lawrence Berkeley National Laboratory, and Kevin McIlwrath and Xiao Feng Zhang of the electron microscope division of Hitachi High Technologies in Pleasanton, Calif.
Now if we can just get some nuke plants built we can eliminate our need for oil from our enemies.
Yep. Couldn’t help but notice the names. Taht means that all of their research is already somewhere in Beijing.
China may well undergo some sort of nasty collapse in the next couple of decades - perhaps even sooner. Their prosperity is a mile wide and an inch deep.
http://www.freerepublic.com/focus/f-news/1941827/postsToshiba's building a "Micro Nuclear" reactor for your garage? Alright, details are slim, and we really have no idea if Toshiba has any plans whatsoever to sell these nuclear reactors to consumers -- in fact, we hope it doesn't -- but it does seem like the company is well on its way to commercializing the design. Toshiba's Micro Nuclear reactors are designed to power a single apartment building or city block, and measure a mere 20-feet by 6-feet. The 200 kilowatt reactor is fully automatic and fail-safe, and is completely self-sustaining. It uses special liquid lithium-6 reservoirs instead of traditional control rods, and can last up to 40 years, making energy for about 5 cents per kilowatt hour. Toshiba has been testing the reactors since 2005, and hopes to install its first reactor in Japan in 2008, with marketing to Europe and America in 2009. Oh, and we lied: we totally want one of these in our garage
Yep. Gives me an idea for a grant request...
damn Stonecutters...
Okay, I guess it’s officially time to reread that.
Fortunately, it’s here in the same room with me.
Govt will institute odd/even recharging days
Just the nanowire battery would cause a huge increase in EV demand. Fleet vehicles, commuter cars, lotsa vehicles are stored overnight every night and then used for only a fixed amount of mileage each day. All of these vehicles could be charged at night when other electric usage is low and then used all day.
Battery substations could be used to smooth out the total demand curve to avoid the need to build or use additional peak-demand generation assets. They could also be used in modular, distributed locations to delay or obviate the need for transmission system upgrades. It might be very useful.
What makes you think they aren’t American?
What if their names were Cohen or Schwarz?
Would you automatically assume they were Israelis?
And yes the Chinese do read and understand the
scholarly journals, so they probably do “have it”.
Sheesh..
Now this is the kind of stuff that’s worthy of a patent. I hope he makes billions.
There was a story recently that electric and hybrid cars plugged-in to the wall could perform that exact function on a distributed basis.
I loved that book.
Watch out for the Hubbardites/Elronners!
I used to have an electric home heating system that charged during the night to provide heat during the day.
I have a current home heating system that I charge during the summer (I cut wood) to provide heat (I burn wood) during the winter.
:)
LOL!
I do that too.
Heinlein and his Red Heads!
Is not Stanford a publicly funded Univercity? Do not that mean that products developed and discoveries made belong to the public?
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