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."
Sony Nanowire Batteries (Score:5, Funny)
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A bit like shrapnel. (Score:2)
Re:A bit like shrapnel. (Score:5, Insightful)
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Re:Sony Nanowire Batteries (Score:5, Funny)
How long before laptop batteries get classified as "munitions"?
Re:Sony Nanowire Batteries (Score:5, Interesting)
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Re:Sony Nanowire Batteries (Score:5, Insightful)
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That's all right, just wait until we're all using supercapacitor-powered laptops...
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I'm amped just reading this... (Score:5, Funny)
Yes, precisely!
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Re:Sony Nanowire Batteries (Score:5, Informative)
http://wiki.xtronics.com/index.php/Energy_density [xtronics.com]
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.
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: (Score:3, Interesting)
I got 20% efficiency for 4 stroke gasoline engines [wikipedia.org], vs 85% for brushless DC electric motors. [wikipedia.org]
Actually there's an article here that quotes the density of the new battery as 3000Wh/kg. [sciencedirect.com]. 12200 as an energy density for old Lithium Ion batteries is completely bogus by the way.
So
12,200*0.2 = 2440
vs
3000*0.85 = 2550
Not as good as you said since the battery still has 4x worse energy density but you're right that engine efficiency makes up for it.
Re:Sony Nanowire Batteries (Score:4, Interesting)
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No argument here, but consider how poorly we make use of energy from gasoline ( at least in cars, trucks, etc ). My understanding of electric motors is that not only do they convert energy to torque much more efficiently, but they don't need a transmission, differential or CV joints ( the latter two if you're using one motor per drive wheel ), which lose quite a bit of torque to heat/sound.
Just saying. Batteries might suck in co
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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.
No
Re:Sony Nanowire Batteries (Score:5, Interesting)
Of course, you're comparing the energy density of the stored electricity, not of the chemical energy of the battery as a whole, which isn't really fair.
Anyways, let's look at vehicle range. The gasoline has 6.25 times the energy density, but only burns at 25-30% efficiency in the engine. The charge/discharge of lithium-ion batteries is almost lossless. The motor would be 85-90% efficient. Looks like, kilogram per kilogram, gasoline gets twice the range. On the other hand, there are other practical considerations -- namely, the fact that electric motors are much smaller and lighter than an internal combustion engine. I wouldn't be surprised if you could shave a hundred, hundred fifty kilograms off the engine/motor mass by switching from ICE to electric. If you filled this remaining space with batteries, that'd be ~900MJ, the equivalent of 20 gallons of gasoline, extra for the electric vehicle. Factor in a 12 gallon gas tank that's being replaced by electric (that's what my Saturn has, so that's the number I'm using), that's the equivalent of 26 gallons of range for the electric and 12 gallons of range for the gasoline vehicle. The electric goes over twice as far. But it gets even better, as you'll only get your optimum 25-30% gasoline efficiency at the optimal RPM; they perform poorly at low speeds, for example. Electrics perform well over a wide range. Then you need to factor in that the electric has all of the benefits of hybrid vehicles already there -- regenerative braking, no waste at stop lights, and so forth. All in all, I'd expect around three times more range with an electric using batteries like these than you get in a gasoline vehicle. And to top it all off, given that they're using nanowires, the surface are will be incredible, so the charge time should be very fast -- just a few minutes.
If this is legit, and if there aren't any degradation or safety problems that sneak up on them, when it comes out, gasoline vehicles can be expected to go "extinct" quite quickly. Who *wouldn't* want to be able to drive a thousand, perhaps even two thousand miles on a single charge, at a price of 1-2 cents per mile?
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:5, Informative)
There's your problem right there. Li-ion batteries have a charge efficiency of around 99.9% [batteryuniversity.com]; you're two orders of magnitude off. Even if you go off by an order of magnitude and say 99% efficient, assuming a specific heat of 1J/g*C, with 7.2MJ/kg, that's only a 72 degree rise in temperature over 5 minutes or so (240W of heat), which a cooling system could easily manage (your computer case fan probably dissipates more heat than that). With the actual 99.9% efficiency, it's a 7.2 degree rise in temperature and 24W of heat, respectively.
The other issue is that we (US) have nowhere near the generation capacity to handle a nation full of electric cars.
Another widespread false concern. The fact is that the US has significant surplus generation capacity at night, more than enough to begin the transition (it's not like everyone collectively throws out their vehicles and switches at once). Furthermore, it's much *cheaper* to build new electricity production infrastructure than it is to produce gasoline production infrastructure. And, for gasoline-powered cars, you have to keep producing new gasoline-production infrastructure even when gasoline demand remains constant since oil fields run dry. You're just replacing one type of infrastructure demand with another -- one that's easier to meet to boot.
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Energy/volume constant? (Score:2)
I think we're going to see quite a few more stories about battery recalls and killer cellphones.
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This is going to be expensive in the beginning. Companies will be looking for a way to leverage the new tech without the battery becoming more expensive than all the other parts combined. But they might still have an advantage without breaking the bank t
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They're going to put Extenze (and Viagra) out of business with a product like this.
On the bright side we won't have to see any more commercials of the chick with the freaky eyes.
Re:Sony Nanowire Batteries (Score:5, Funny)
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Re:Sony Nanowire Batteries (Score:5, Funny)
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Batteries of 1/5th the size and twice the battery life. A lot of companies say they want to work on longer battery life, but what they don't say is they don't want to trade weight for it. Youc an always add more battery life by adding more battery weight. Personally, I wouldn't mind swapping my 1/2kg LiIon for a 2kg LiIon for 4x the battery life in some cases, but apparantly not many people agree.
Promising (Score:3, Interesting)
It may very well be the leap that keeps battery technology ahead of ultra-capacitors for the foreseeable future.
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Re:Promising (Score:5, Informative)
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They do. It is just not as strong and the battery manufacturers conveniently omit it. Also Li-Ion
suffers from enforced capacity degradation, since, unlike NiCad, overcharging can make them explode and measuring battery capacity is tricky, so the battery controller lest you put in a little less every time you recharge.
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Three things that affect LiIon life:
(1) Stored with charge too low, or high (memory effect like results)
(2) Stored to warm
(3) Over-drained (memory effect like results).
Of course, the worst culprit, which seems to drag them to their knees after not much time at all: age.
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Re:Promising (Score:4, Interesting)
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A major hindrance is cost versus return. Assuming no degradation, it still take years to break even, and when considering the life of a panel you are lucky to break even before disposal.
If I could spend 2 grand and break even in a year, and get five years of use out of it I would be solar ASAP. As it stands it's still not practical for most people.
Solar isn't there yet. Sure it's a lot better then in the 70s.
Now what you could do is use it to store energy gather
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Wow, you have no familiarity with the concept of long-term investments do you? No, solar isn't an economical investment in most places. But if you expect your investments to return your expenditures in one year, I'd hate to see what your retirement plan looks like.
For anyone interested in seeing how the economics of solar power works out where they live, check out this handy-dandy photovoltaics economics calculator [daughtersoftiresias.org].
Smaller lighter batteries (Score:5, Insightful)
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It's 1024 numbers, but it only goes to 1023
1111111111 = 1023
Re:Smaller lighter batteries (Score:4, Funny)
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Actually with some thought, a human can count to over 2 million on their hands. Ever considered about rotating your hand by 180 degrees as part of your numbering system? It is commonly done in american sign language to count to 100 on one hand. Using three positions per hand, you can count to over 1.2 times 10 to the 27th power. Of course, trying to remember hand positions in such a system would likely be difficult.
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Great, more unworkably small displays, keypads and other tactile/visual HIDs.
I think many of those devices have already reached the limit
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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.
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Re:Uh, maybe 1023? (Score:2)
Uh, shouldn't that be count to 1023?
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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.
How small, exactly, are you and your hands? Or, perhaps a better question to ask is, how large is your battery with respect to your phone? I have a small phone (Nokia 3220). The phone's dimensions are 104 x 44 x 18.8 mm, and the battery is maybe 1/8 of its size, if that large. My broken phone (Sony Ericsson T630i), is 102 x 43 x 17 mm. Granted, this phone's battery was proportionally larger than the one in my Nokia, but still, I couldn't imagine the thing much smaller. The only way you could shrink i
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Thickness of paper? (Score:2)
Making the assumption that the reference for comparison is standard 20lb bond paper, a sheet is approximately 0.0038 inches thick [paper-paper.com]. So, we're talking 0.0038 mils once the 1/1000th thickness factor is added.
Anyone care to convert this into lengths of football fields or Empire State Building height units? <grin>
Re:Thickness of paper? (Score:4, Funny)
*including tower
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.)
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Getting a patent is a huge motivator for research professors. Mostly for academic reasons. I do agree with you in principle however: He should be on the patent, but the patent should be public domain.
Re:patent (Score:5, Informative)
I'm sure Stanford has made a killing by licensing to or investing in companies. Here's a list of their startup investments - not necessarily patent related, but I'm sure many were founded by Stanford professors or alumni with patents licensed back from the university...
http://otl.stanford.edu/about/resources/equity.html [stanford.edu]
They probably made over a billion on Google alone...
Because of the Bayh-Dole act (Score:5, Informative)
Because of the Bayh-Dole Act [wikipedia.org], which commercialized federally-funded research.
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As for why he gets the patent, well, inventors are named on patents, that's pretty much how it works, but the rights to exploit the patent are probably more complex, and possibly equitable, depending on all the factors cited.
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"The Employee hereby assigns and transfers to the Company without further consideration his entire right, title and interest in and to all Inventions developed while in the employ of the Company."
Sign on the dotted
Assuming this in't hype and (Score:2)
Right now the biggest reason for not buying an electric car is range. If my car that gets 120 miles on a charge now gets 1200 miles, I can not travel cross country in it and only need to charge at night.
Or bette, they can make bigger cars that get 600 mile range. That seems to me to be the 'tipping point' for acceptance.
We can discuss how much people 'need' but the fact is people feel they need more, and t
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Almost (Score:2)
That's the harder part, I would think. As a commuter vehicle, I would LOVE to be able to trickle-charge a car in my garage at night and never have to visit a fuel station except on longer road trips, though.
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For the sake of argument, lets say 1 charge = 1 tank of gas for the same vehicle.
How much more money would you pay for the vehicle to never put gas in it?
I fill up every two weeks for 30 bucks. call it 60 bucks a month.(yeah, I know 4.33 weeks in a month.)
If I pay 10 cents a kilowatt I would need a car that uses no more then 300Kw a month to break even.
The Telsa Roadster goes 245 miles on 54Kw.
I probably drive 300 miles every two weeks.
So I would save money on energy.
My point here is that apparently I
4277mA hours per gram (Score:5, Informative)
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The most I have seen in a AA battery is 2650 (although this is NiMH), so in comparison: 1 AA battery is roughly 15-20 grams (estimated).
15 x 4277 = 64155mAh
20 x 4277 = 85540mAh
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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.
Re:Any work on the flip side? (Score:4, Informative)
You mean like this one? [laptop.org]
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1) SSD Hard Drive. [tomshardware.com] The hard drive is one of the biggest power consumers in the laptop today, by changing to an SSD, this can be drastically reduced. Yes, they are more expensive and they are smaller capacity than a HD, but in addition to being less power hungry, they are also much faster, smaller, and lighter.
2) Digital Paper Displays. [cdrinfo.com] The back lighting required by current LCDs is very expensive to run
Not quite (Score:2)
Either way, I have a hard time believing these things have a stable capacity after cycling. Fracturing is not the only problem in silicon electrodes. As the li
"Amount" of electricity???? (Score:2)
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I do agree that it stores rather than produces though.
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:Critical questions of how (Score:5, Funny)
If you have to ask you can't afford it.
2) How long does it take to charge
Not too long, plug it in and wait for the amber light to turn green.
3) How many charges can you get in its lifetime.
If its made by Apple you can charge it as many times as you want, but replacing it will cost about 82% of the original cost of the full price of the original device you bought it for UNLESS you buy an Apple Care Plan for 73% of the full price of the original device you bought it for.
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. They will ALL be deficient to one person or another...therefore the technology will be worthless in some aspect by someone. Why is it that people only want to use it in electric cars? I'm sure all the single and lonely women wouldn't mind having a device that doesn't quit on them before they're TRULY satisfied...which will never happen because women are never satisfied. Thats why its called a ball and chain.
My money is still on ultra-capacitors.
You fool. My money is in Gold because the Fiat System will fail at some point and you can't buy food with ultra-capacitors...
The Hard Part...Commercialization (Score:4, Interesting)
Given that the initial results suggest an energy density increase of an order of magnitude, I suspect VCs are already crawling into Palo Alto & up to Standford.
What happens between the "experiment" where a 10/1 advantage is produced, to the final produceable & safe product, it is not uncommon to see 10/1 advantages slip to 5/1.
Other notes in this thread have joked at 10 times the explosive power, which battery manufacturers have worked out in existing batteries, but this one will offer BIGGER challenges. I wouldn't know how to calculate the "explosive power" of the end design if safeties failed, but this will be critical.
Any serious damage which might cause a catastrophic short would cause some companies to NOT accept these batteries, like airlines for instance. My pure guess is that physical damage, in say an automobile accident, or similar "mashing", will make the design of safety features be what takes the most time and effort.
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After which they will realize they where lost and find their way to Stanford.
Hundreds of pages? (Score:2, Offtopic)
Although I find it despicable that printers might under-report their ink capacity (though I always though it was a "buy ink" warning rather than a "put new ink in" warning. An important distinction, as you want to have fresh ink handy *before* you actually run out), I find it very difficult to believe that even the most
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That'll be the tracking dots:
Clicky! [eff.org]Re: (Score:2)
Electric car revolution? (Score:2)
I don't know what the odds are that this new tech could be used in electric car batteries... but if it provided a comparable "usage" boost (2 hours vs. 20 hours for laptops = 10-fold increase)
The old Volt got ~100 miles on a charge... if a similar increase was had due to this technology, it'd make a car like the Volt get 1000 miles to a charge... which would be amazing. I'm just speculating, mind you.
Problem already solved (Score:2)
Re:would this be a deserving patent (Score:4, Insightful)
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Wrong. (Score:4, Informative)
That's highly incorrect. Lithium ion batteries have a self-discharge rate of about 5% per month. However, while the battery is connected to a power supply, some energy is always consumed, just like the way desktop PSUs consume power when the computer is off, but when the PSU cutoff switch is not switched off. That's why laptops will not stay charged for months when unused. Take the battery OUT of the laptop, and you will be able to power it on a year after you turn it off.
Low-self-discharge (LSD) NiMH cells (such as Sanyo Eneloop) have discharge rates that are even lower... up to as little as 20% per year.
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