Stanford (CA) - Researchers at Stanford University have discovered a way to utilize silicon nanowires in such a way as to reinvent the rechargeable Lithium-Ion battery.  This find produces 10x the electricity of existing Li-ion batteries, leading to the 20-hour notebook.  The lead researcher is calling it "a revolutionary development".


Silicon nanowires
A paper published on December 16, 2007, in Nature Nanotechnology, entitled "High-performance lithium battery anodes using silicon nanowires", written by Yi Cui, assistant professor of materials science and engineering at Stanford, explains the device.  Cui describes the process as a re-examination and reinvention of the known, natural swelling when silicon is exposed to lithium, as is shown in this image.

Note:  both images were taken at the same magnification, one before exposure to lithium, the other after.

The silicon swells as it absorbs positively charged lithium atoms during the charging phase.  Later, when it's called to give off electricity during use, it deflates back to its smaller size.


History
Silicon battery technology began about 30 years ago.  Researchers had been pursuing larger silicon assemblies which would quickly fracture and damage the battery, making for almost immediately decreased output and extremely low battery lifetimes.  Cui chose to investigate silicon nanowires because unlike larger silicon structures, they do not fracture. This is true even upon repeated charge/depletion cycles.

The results are so far ahead of what was expected that Cui is looking for additional applications.  He would like to see wide use of the new batteries as viable home storage units for rooftop solar panels, electric car batteries which last 10x as long, as well as the traditional uses in cell phones and notebooks for 10x the usable life.


Conclusion
When I interviewed Mooly Eden at Fall IDF 2007 in San Francisco, CA, I asked him if he was aware of any new battery technologies which would significantly impact the usable life of portable devices.  He said yes, but refused to comment further about what that technology was.  I think we may have found it here.

A battery providing 20 hours of usable notebook life would change the face of mobile computing.  It would be enough for two days of business use from 8am - 5pm.  It would be enough to watch 6 to 7 movies during plane flights or long trips.  And as far as cars go, it could allow future vehicles to drive not 120 miles on a single charge, but 1,200 miles.

Technology innovations like this can literally change our world.

Research

Dec 20, 2007 13:23     

It will be good if we can use this technology for electrical car .
Doug report abuse vote down vote up Votes: +0

About time

Dec 20, 2007 19:14     

It's about time something like this was invented. It will be great for electrical cars for the sole purpose of attracting people to buy it... it will not really reduce the energy cost(average american drives under 120 miles in a day). I was confused, could it last longer on the same energy, or hold more energy? If it could last longer on the same energy, i take back what i said about not reducing the energy cost.

Mike report abuse vote down vote up Votes: +0

Price

Dec 20, 2007 19:48     

I wonder how expensive this type of battery? If that density is achievable think about how small could future devices be with today's runtime.
westfork report abuse vote down vote up Votes: +0

mp3 player

Dec 20, 2007 20:40     

My current mp3 player runs out of juice before I've played back anywhere near it's data storage capacity. It would be nice to have batterys that can keep up with their applications. [With hard drives getting perpendicular, that's 30,000 songs! "Yeah, I used to carry my iPod everywhere, but when I insisted that it be able to keep up with their song list, the extra 40 pounds of batteries just killed me." :) -Rick]

Allan report abuse vote down vote up Votes: +0

to market time

Dec 21, 2007 02:38     

whats the current estimated timeline? 2015? 2010? 2009? I would like to see this applied everywhere by next week personally, my laptop battery barely lasts one two hour lecture.. and thats on 'battery saving' mode at 20% max cpu and 10&#xma;x gpu and only about
skythra report abuse vote down vote up Votes: +0

"Cui chose to investigate silicon nanowires because...

Dec 21, 2007 02:39     

"Cui chose to investigate silicon nanowires because unlike larger silicon structures, they do not fracture. This is true even upon repeated charge/depletion cycles." This is more interesting IMO. (iPhone battery replacement troubles included) Smaller chips that consume even less, batteries needing to be 100s of times smaller as a result and some kind of wireless recharging technology and we would have a GPS, cell phone and credit card (unique person identifier everywhere) always with us (maybe under the skin). A long time ago it was said that you were a geek if your wristwatch had more processing power than a 486sx. Today, anything less would be a waste of space and material... Seriously, at what point of development are human hibernation techniques? I can't wait to see all of this happen!

Virtualban report abuse vote down vote up Votes: +0

Efficiency

Dec 21, 2007 07:07     

I would love to see the efficiency of these, as well as the the discarge time. If the battery looses it's charge rapidly then low drain devices wouldn't benifit. However high-Drain devices still would. I've seen a NiMh that can hold a full charge 6mo, still a waste for my TV remote I only have to change Alk every year and a half or so. Also number of charging cycles and half life would be interesting to see. Any Ideas Rick? [According to the release, the silicon nanowires of that size do not break under repeated stress. They are small enough that their molecular structure allows them to be very malleable. -Rick]

N report abuse vote down vote up Votes: +0

how much?

Dec 23, 2007 21:34     

sounds cool. until they jack me for 10x the price of a regular battery.
scott report abuse vote down vote up Votes: +0

Human hybernation....

Dec 24, 2007 07:30     

Last time I checked researchers were still trying to find an additive to or a way to temporarily replace the blood inside the body (without killing it) so stop the crystallization process that occurs at such low temperatures. Without a solution your body literally cuts itself to shreds from the inside out. This is the main roadblock at this moment and the most important reason why you would not survive true suspended animation. There are another researches that instead of completely shutting down the body try to slow it down. The ones I have read have exposed mice to some chemicals in order to induce the comatose-like deep sleep.

Magius report abuse vote down vote up Votes: +0