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"Spin Battery" Effect Discovered
An anonymous reader writes "Researchers at the University of Miami and at the Universities of Tokyo and Tohoku, in Japan, have discovered a spin battery effect: the ability to store energy into the magnetic spin of a material and to later extract that energy as electricity, without a chemical reaction. The researchers have built an actual device to demonstrate the effect that has a diameter about that of a human hair. This is a potentially game-changing discovery that could affect battery and other technologies. Quoting: Although the actual device... cannot even light up an LED..., the energy that might be stored in this way could potentially run a car for miles. The possibilities are endless, Barnes said.'"
This sounds cool, but what they are not telling you is that it will stop working if you bring it south of the equator. :)
"The price good men pay for indifference to public affairs is to be ruled by evil men." ~Plato (427-347 BC)
Is this due to the scale of the device/experiment or is it a limitation in the output that they can get it to generate so far?
...the energy that might be stored in this way could potentially run a car for miles. The possibilities are endless, Barnes said.
Awesome, I have yet to travel miles by car.
I am the lawn!
Oh, yeah. We know how the spin works. But it works only in the PR side of things.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
In THIS house, we obey the laws of thermodynamics. So you create a magnetic field, okay. Great. What's to prevent everything that's metallic in the area from moving around it, inducing current in it, and converting it into useless thermal energy? In other words -- what's preventing the battery from discharging? It might be good for a really high-capacity capacitor, but a battery? Batteries are long term.
#fuckbeta #iamslashdot #dicemustdie
Do not open or crush battery. Severe risk of releasing a life-sucking vortex.
Do not dispose in fire. Doing so could loose a storm of flaming vortices.
Do not use this battery on carnival rides, while figure skating, or place in spinning clothes washer. Risk of severe gyroscopic reactions, which may lead to property damage, personal injury or death.
If this does prove to be useful for batteries, would it eliminate issues related to battery memory?
It appears current rechargeable batteries "age" due to chemical reactions even if not used. Even more so due to repeated charge cycles.
With no chemical reactions in play, does this mean people won't be forced to upgrade their phones simply because their battery is all but dead?
I though someone had got the induced decay of Hf spin isomers to work.
http://en.wikipedia.org/wiki/Induced_gamma_emission
1300 megajoules per gram would be a good battery.
Although the actual device... cannot even light up an LED...
So you're telling me this thing is less powerful than a potato?
... and not all of it from the magnets themselves.
At least for the proof of concept stage, they might want to make a light source that consumes significantly less juice than an LED, and has a greater tolerance for fluctuation.
From Wikipedia:
"LEDs must be supplied with the voltage above the threshold and a current below the rating. This can involve series resistors or current-regulated power supplies." http://en.wikipedia.org/wiki/Led#Disadvantages
Using an LED as an example of what this tiny power souce can't power seems futile at this point.
Readers with subscriptions can see the whole paper.
Dog is my co-pilot.
I for one welcome the new SI unit human hair diameter overlord.
That we're talking about _spin_ here, as in a property of subatomic particles corresponding to an 'intrinsic' angular momentum, not as in something that's physically 'spinning'. Electrons spin +1/2 or -1/2 and that's it. They can't stop. The energy here is being stored in the form of the _orientations_ of these spins, not the spin itself. What's keeping them that way is conservation of spin. Which is analogous to conservation of angular momentum. (Bound) Electrons can't change their spin state spontaneously. Which is why stuff which is magnetized stays that way for a long time. It's also the reason for phosphorescence. While I think what they've done here is undeniably pretty cool, in turning spin-state transitions into electricity directly, it's probably not going to create any real competition for conventional batteries, for fairly simple reasons. Batteries store electricity in the form of chemical redox states, which means adding/removing electrons from atoms/ions. The energy differences between spin states are typically an order of magnitude smaller than the energy difference between redox states.
moving parts in computers (and apparently can act as a replacement for the transistor).
I don't think this is a replacement for the transistor, there certainly wasn't any indication that these can perform any logic operations. A replacement for your hard drive, which besides the fan (which you will probably still need), is the moving parts of your computer. It remains to be seen whether this process could be useful at scale. You need billions of these little things, along with some method for reading and writing to each unit. The HDD industry has been working for years (still in R&D phase) on spintronics to store data, and there is still a long way to go. But there is indeed great promise in it as well.
Prediction: The real iPhone killer is going to be sex robots from Japan. Think about it.
Spintronics is a little too far out of my ken (I was always more of a radiation physicist, where everything comes in nice little packages instead of fields), but if I'm reading the paper correctly, they're saying that they can apply a static magnetic field to one of these devices and then can measure a voltage drop across a resistor hooked up to the device. They can get a few millivolts from a 1.2 Tesla field, which persists for at least ten minutes but does decay in that time frame. When they remove the magnetic field, the voltage disappears.
I guess my question is that if the field is static, where is the energy coming from that drives the current giving rise to the voltage? I'm also wondering how one regenerates the voltage after it discharges completely.
Bypassing the layers of blogs, here's the actual paper. But it costs $32 to read more than the abstract.
This is an application of superparamagnetism. Paramagnetism is ordinarily a weak phenomenon, but there are some new materials for which this effect is much stronger.
It's too early to tell if this is useful. Right now, it's in the category of "minor development in materials science overpromoted as a major breakthrough". It might turn out to have some relevance to MRI imaging or disk drives, both of which rely on fine-scale magnetic effects.
Article describes that nano-magnets apply a large magnetic field to "wound-up" the spin-battery.
Having charged the hypothetical battery the article claims, the one that can run a car for miles. It is possible to discharge this battery near instantaneously, that should theoretically generate an EMP without a nuke. Something the military would be interested in.
Off to patent my idea now.
Scientists think that with a few modifications the new technology could work with kilometres too, though it would still be recommended that the host country is a monarchy or at least a strongly-presidental republic.
Other technical difficulties like the extremely strong gyroscopic effect should be overcome as well.
(search on keyword "battery" if you don't want to read all the way through)
http://www.theatlantic.com/doc/200904/chinese-innovation/3
Some here may already have read about this, but it appears that China makes some very good batteries, mainly for the electronics industry. Now, it seems they had not long ago seen a company produce (ugly) electric cars, but batteries that rival the USA Big 3 (well, which of them's big anymore?) and even Tesla. Given that Tesla's demo/sports car ran over $100k, and despite their announced sedan:
http://www.autoblog.com/2008/02/17/tesla-whitestar-electric-sedan-to-debut-this-year/
there is going to be some stiff global competition for such batteries, especially if what Chinese companies are working on can take off.
To recap the recent Detroit Show:
http://www.theatlantic.com/doc/200901u/detroit-auto-show
Previously: "Linux... Toward the Sunrise..." Now: "Linux... Toward the-- No, now, part of Every Sunrise"