Nanowires Boost Laptop Battery Life to 20 Hours 238
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."
Smaller lighter batteries (Score:5, Insightful)
patent (Score:2, Insightful)
I would say he was employed by Stanford. So Stanford should receive the patent. If his research-money was provided by a public institution (some sort of grant), then either the research should be public (patent-free), or the patent should be somehow associated to the country.
I don't see why he gets to profit from the discovery. (After all he was payed to do that. It would have been bad, if he hadn't found anything.)
Re:would this be a deserving patent (Score:4, Insightful)
Re:patent (Score:1, Insightful)
Any work on the flip side? (Score:5, Insightful)
With clever engineering it should be possible to make a laptop exclusively used in low power mode solar powered if it's normally left out when not in use.
Critical questions of how (Score:4, Insightful)
2) How long does it take to charge
3) How many charges can you get in its lifetime.
If any one of those is a major deficiency, the technology will be worthless. Since they didn't immediately bring up use in electric cars, I'm guessing there's currently a fatal flaw that applies to one of those questions.
My money is still on ultra-capacitors.
Re:Sony Nanowire Batteries (Score:5, Insightful)
Re:Smaller lighter batteries (Score:3, Insightful)
Great, more unworkably small displays, keypads and other tactile/visual HIDs.
I think many of those devices have already reached the limit where size is impeding usability and ruggedness. I personally cannot stand squinting at video on sub-3" LCDs and hate my current cell phone's ~1" wide keypad.
Re:Smaller lighter batteries (Score:2, Insightful)
Or, keep the device sizes the same, reduce the battery size and add more functionality/technology/features/etc in said device.
Shrink a battery in a laptop and you can have enough extra room to have an additional 2-3 hard drives if one wanted.
Re:A bit like shrapnel. (Score:5, Insightful)
Re:Sony Nanowire Batteries (Score:5, Insightful)
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.Re:Sony Nanowire Batteries (Score:4, Insightful)
The first is heat from charging. If you use your figure of 900MJ, and charging is 90% efficient, that means you have to dissipate 90MJ of heat during the charge. 1J = 1Ws, so 90MJ is 25kWh of heat energy. That's 1kW if charging takes one day, or 4kW if it takes 6 hours. That's probably way too much heat for the battery/car to take. (assuming my math/conversions are correct!) Of course, that only applies if you're charging all at once. Charge time wouldn't be as much of an issue if you charge whenever you're not using the car.
The other issue is that we (US) have nowhere near the generation capacity to handle a nation full of electric cars. We'd have to start building a lot of extra capacity, seeing as how we sometimes have a hard time keeping up with demand as it is. On the other hand, everyone having a huge battery plugged into the grid could do a lot to help smooth out peak demand.
Re:Sony Nanowire Batteries (Score:3, Insightful)
Ah yes but. In a car, an electric car, it had one property no gas power car can ever have - you can recharge it with sunlight. I work at home and I don't go on daily commutes. Some weeks I may go to the store a few times and that's it. A moderate solar array might in some cases eliminate or at least diminish the need to plug the car in and pay for electricty. There's a certain appeal to that that in some sense overrides all other desirable features in a car.
Now if these batteries can take a 2 hour laptop and give you 20 hours from it, uh does that mean the Tesla roadster now can do 4000 miles instead of 400 miles? That would be kinda significant...
On that note... (Score:2, Insightful)
**reaches for tin foil hat**