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Nanowires Boost Laptop Battery Life to 20 Hours

Posted by ScuttleMonkey on from the more-bang-for-your-buck dept.

brianmed writes to tell us that Stanford researchers have created a new use for silicon nanowires that promise to reinvent lithium-ion batteries. "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. [...] 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."

2 of 238 comments (clear)

  1. Re:Promising by TheRaven64 · · Score: 5, Informative

    It's not exactly a memory effect, but LiIon batteries do degrade over time. Unlike NiCd cells, their life is best preserved by keeping them about around 50% charge. You get a lot of people complaining that their batteries wear out quickly because they still think the things they learned about NiCd cells apply, so they fully discharge and recharge their LiIon cells, which is the absolute worst case for them.

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  2. Re:Sony Nanowire Batteries by Hal_Porter · · Score: 5, Informative

    How does the power density of these compare to gasoline? Lousy

    http://wiki.xtronics.com/index.php/Energy_density

    Material Volumetric(Wh/l)Gravimetric (Wh/kg)

    Fission of U-235 4.7 x 1012 2.5 x1010
    Boron 38,278 16361
    JP10 (dicyclopentadiene)10,975 11,694
    Diesel 10,942 13,762
    Gasoline 9,700 12,200
    Black Coal solid =>CO2 9444 6667
    LNG 7,216 12,100
    Propane (liquid) 7,500 - 6,600 13,900
    Black Coal Bulk =>CO2 6278 6667
    Ethanol 6,100 7,850
    Methanol 4,600 6,400
    Liquid H2 2,600 39,000
    Secondary LiOn Polymer 300 130 - 1200
    Secondary Lithium-Ion 300 110
    Nickel Metal Hydride 100 Wh/l 60Wh/kg
    Lead Acid Battery 40 25
    Propane (Gas - 1 bar) 28.1 13,900
    Compressed Air 17 34
    Ice to water 9.3 9.3

    If this new battery is 10x as efficient it is still 3x worse than gasoline.
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