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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. Smaller lighter batteries by farnsaw · · Score: 5, Insightful

    Rather than tripling the life of a current battery, I can see this being used to power a laptop off a battery the size of a current cell phone battery and shrinking cell phone batteries to the size of a nickel. This will drastically reduce the size of several of our common devices such as Bluetooth headsets, cell phones, iPods (and other MP3 players), digital cameras, etc. In many such devices, the battery is still the single largest and heaviest component and being able to shrink this by a factor of 3-5 will drastically affect the size and weight of them.

    --
    "Computer Scientists can count to 1024 on their fingers" (non-mutant, non-mutilatated, human computer scientists)
  2. Re:Sony Nanowire Batteries by OwnedByTwoCats · · Score: 5, Insightful

    Gasoline 9,700 12,200

    ...
    Secondary LiOn Polymer 300 130 - 1200
    Do the rest of the math.

    300 * 10 is 3000, so gasoline still stores three times as much potential chemical energy as the battery. But converting chemical potential energy into motion through an internal combustion engine is about 30% efficient, while power electronics and electric motors net between 80 and 95% efficient.

    • Battery: 3000 * 0.8 = 2400
    • Gasoline: 9,700 * 0.3 = 2910
    so getting batteries to within 80% of gasoline (i.e. same volumetric energy density as a vehicle fuel as ethanol) really is revolutionary.


    If these Li-Ion batteries are on the lighter end of the scale, the energy/weight figures could be extrordinary.

    • Battery: 1200 * 10 (improvement from research) * 0.8 (efficiency) = 9600 watt-hours traction per kilogram
    • Gasoline: 12200 * 0.3 (efficiency) = 3660 watt-hours traction per kilogram.
    This is breakthrough territory.