A 40-Hour Laptop Battery by a (Silicon) Whisker
by Jeremy Elton Jacquot, Los Angeles on 12.19.07
The latest breakthrough in lithium ion battery technology may not sound all that impressive. After all, we're just talking about some modifications to the battery's anode - a set of silicon whisker-like wires - hardly anything earthshattering. Yet, if you believe the claims of Stanford materials scientist Yi Cui, this modification could allow batteries to store up to 10 times the charge of conventional rechargeables - enough juice to power a laptop for almost 2 full days.
Anodes in lithium ion batteries have traditionally been made up of layers of carbon atoms (graphite), 6 of which hold onto each individual lithium ion; lithium ions provide the power for a device by unloading the extra electrons they grabbed during the charging process. Because each silicon atom is capable of holding 4 lithium ions, it's long been thought that silicon would work much better than carbon in extending batteries' longevity.
Past attempts to use silicon films or particles in batteries had failed, however, because the large number of lithium atoms had destroyed the silicon, breaking its contact with the metal substrate and drastically reducing the batteries' longevity. Cui and his colleagues were able to resolve this issue by growing a bunch of flexible silicon nanowires directly bonded to a stainless steel base - ensuring they wouldn't break away under the stress of the lithium atoms. To relieve the strain, the nanowires were able to contract and expand radially as needed.
Gerbrand Ceder, a materials scientist at MIT, said that for the technology to move past the concept stage, Cui's team would first need to find a way to get the cathode to hold 10 times the charge as well. If they are successful in accomplishing this, we may all soon be looking at much longer battery lives.
Via ::ScienceNOW: A 40-Hour Laptop Battery? (news website)
See also: ::New Fuel Cell Design Could Help Laptops Run 5 to 10 Times Longer, ::Bike Powered Notebook Computer, ::Notepower Brings the Sun to Your Lap
"if you believe the claims of Stanford materials scientist Yi Cui" ... ummm why are you using language that could cast doubt on his findings? If a Stanford materials scientist says something then they usually have the research to back themselves up. Stanford, like most major research universities, is not given over to allow their fellows to make unsupported gaffes. Using neutral words like "According to" would be better in this post and would not inadvertently create doubt in your readers' minds.
Using this method of battery construction, is the amount of Lithium metal required per kWh of energy similarly scaled down to 1/10th of the current 0.3 kg per kWh in a traditional LiIon battery? If so, this is a huge development, as peak Lithium is arguably the biggest obstacle in scaling BEVs and PHEVs up to the size of our global fleet of commuter cars.
I urge anyone interested in EVs to check out a great research article about Lithium extraction - http://www.meridian-int-res.com/Projects/EVRsrch.htm
This is a serious issue for the future of EVs.
One problem with net journalism (blogs, etc.) is that the news is often repeated or summarized from other sources where the writers don't have access to the first hand sources of information.
For instance, for a story like this, it would have been very nice for the writer to have actually been able to ask one of the scientists how long this technology might take to commercialize. I imagine none of the researchers would have said that it's possible it would be "soon." Though without any statement as to what soon means to this writer, I suppose I really can't dispute it too strenuously.
BTW, what did you mean by soon... 5 years, 10 years, 20 years, 50 years?
GM volt blog has an interview with Dr. Cui. He states that a commercial product is likely in 5 years.
http://www.gm-volt.com/2007/12/21/gm-voltcom-interview-with-dr-cui-inventor-of-silicon-nanowire-lithium-ion-battery-breakthrough/
Don’t use any external devices. USB and PC-Cards (aka PC-MCIA) use your battery to function, even when you aren’t using them! Have an EVDO card or maybe a USB mouse? Remove them if you can. Even a memory card reader in your PC-MCIA slot uses power just by being in there. The effect varies based on the type of device, but even a few minutes here and there (as you’ll see) add up significantly.
2. Don’t use any external devices. USB and PC-Cards (aka PC-MCIA) use your battery to function, even when you aren’t using them! Have an EVDO card or maybe a USB mouse? Remove them if you can. Even a memory card reader in your PC-MCIA slot uses power just by being in there. The effect varies based on the type of device, but even a few minutes here and there (as you’ll see) add up significantly.
2. Don’t use any external devices. USB and PC-Cards (aka PC-MCIA) use your battery to function, even when you aren’t using them! Have an EVDO card or maybe a USB mouse? Remove them if you can. Even a memory card reader in your PC-MCIA slot uses power just by being in there. The effect varies based on the type of device, but even a few minutes here and there (as you’ll see) add up significantly.
Spare Parts Warehouse has laptop batteries and notebook batteries for major laptop brands such as ACER, Compaq ,DELL, IBM, HP, Toshiba, Sony, Apple, Gateway, and Fujitsu. We offer genuine factory direct and 3rd party replacement laptop batteries, or you can also select from our inventory of pre-owned laptop or notebook batteries. Place an order before 2:30PM EST and your laptop battery or notebook battery will usually ship the same day. We also carry a large inventory of laptop parts and accessories. Click here to browse our laptop parts inventory.
Thank you for this outstanding article.I thought Centrino was the best technology for laptop battery performance.
thanks,Other small improvements in battery life may be gained by the ability to turn off USB ports individually to save power.