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Nuclear Battery That Runs 10 Years
Jenny writes "A battery with a lifespan measured in decades is in development at the University of Rochester, as scientists demonstrate a new fabrication method that in its roughest form is already 10 times more efficient than current nuclear batteries -- and has the potential to be nearly 200 times more efficient. Similar to the way solar panels work by catching photons from the sun and turning them into current, the science of betavoltaics uses silicon to capture electrons emitted from a radioactive gas, such as tritium, to form a current. As the electrons strike a special pair of layers called a 'p-n junction,' a current results. I can imagine lots of applications for this new battery including my own laptop."
Before going off and thinking that a radioactive battery would be bad because
of toxic exposure through its mere presense, please read this Wikipedia article about Tritium, which explains
that " The low-energy beta radiation from tritium cannot penetrate human skin, so tritium is only dangerous if inhaled or ingested."
So it might make a good candidate for a household battery.
How does tritium affect people's health?
As with all ionizing radiation, exposure to tritium increases the risk of developing cancer. However, tritium is one of the least dangerous radionuclides because it emits very weak radiation and leaves the body relatively quickly. Since tritium is almost always found as water, it goes directly into soft tissues and organs. The associated dose to these tissues are generally uniform and dependent on the tissues' water content.
How does tritium change in the environment?
Tritium readily forms water when exposed to oxygen. As it undergoes radioactive decay, tritium emits a very weak beta particle and transforms to stable, nonradioactive helium. Tritium has a half-life of 12.3 years.
How do people come in contact with tritium?
People are exposed to small amounts of tritium every day, since it is widely dispersed in the environment and in the food chain. People who live near or work in federal weapons facilities or nuclear fuel cycle facilities may have increased exposure. People working in research laboratories may also come in contact with tritium.
How does tritium get into the body?
Tritium primarily enters the body when people swallow tritiated water. People may also inhale tritium as a gas in the air, and absorb it through their skin.
What does tritium do once it gets into the body?
Tritium is almost always found as water, or "tritiated" water. Once tritium enters the body, it disperses quickly and is uniformly distributed throughout the body. Tritium is excreted through the urine within a month or so after ingestion. Organically bound tritium (tritium that is incorporated in organic compounds) can remain in the body for a longer period.
Obliteracy: Words with explosions
Betavoltaics? I'll wait until this radioactive battery is more... stable.
Computers are useless. They can only give you answers.
-- Pablo Picasso
I realize you're joking, but just for the record these *can't* go into a "meltdown" state (what is technically termed a prompt critical reaction). Unlike nucelar reactors which function via nuclear fission, these batteries function by capturing the rays from radioactive materials and converting them into energy. The side effect of this is that these batteries tend to be inherently safe because they can't explode and they produce almost no extra radiation (because they're using the radioactivity directly as a power source).
The biggest concern with batteries such as this is actually cost. Radioactive materials are controlled by the government (although anyone with a license can obtain some through various online webstores) and thus have experienced little competition overall. As a result, prices have stayed high.
As I've said before, one solution to this problem is to lease the battery instead of selling it outright. Given its ten year lifespan, the costs can be spread out over that time. When the battery is exhausted, the manufacturer can then reuse the remaining materials in a new battery, thus slowly driving down the prices.
Javascript + Nintendo DSi = DSiCade
All I can say: ouch.
<^>_<(ô ô)>_<^>
Given the paranoid yet incompetent state of security in this country, every single radioactive battery is probably going to get the bearer stopped by the police at some point. Take a radioactive laptop on a plane? -- Stripsearch. Just wait and see. If Homeland Security's detectors currently false-alarm over the natural radioactive potassium isotopes in bananas - yes, bananas! - then these batteries might get the fisheye from these morons.
p-n junction can be so much more than a diode. A diode is in many cases composed of a single p-n junction, but diode != junction. I totally agree with the poster for calling it that way.
You don't call two p-n junctions in the transistor a diode. You don't call the p-n junction in the solar cell a diode...
The term "diode" can also be applied to a vacuum diode, Schotky diode, etc. neither of which is composed of a p-n junction.
Disclaimer: I am a nuclear engineering graduate student.
This seems like a rather nifty extention of the technology. However, note that the fuel source, tritium, is rather hard and expensive to come by. (The total world supply of the stuff is < 40 kg.) So I see this as a great boon for, say, space probes or other fancy applications where getting your hands on some tritium gas aren't the biggest of concerns on the budget. It'd be interesting to see how they compare to other nuclear batteries that rely on heat from alpha-decay of heavy isotopes like plutonium to generate electrical currents.
As far as all the jokes about a nuclear laptop battery using this technology causing sterility, note that tritium decays via beta emission (i.e. an electron), with a range in solid materials of a few mm, so those energetic electrons will stay in the battery. Your primary concern would be if you somehow cracked the thing open and inhaled the tritium gas -- then those few mm of exposure in your lungs etc. aren't the best things to have around energetic particles. (And, as far as having to ingest nuclear sources, tritium is probably one of the better ones, since not only does it have a relatively short half-life of ~12 years, but it gets flushed out of the body rather rapidly as it diffuses into the bloodstream/water in tissues, leading to a much shorter effective biological half-life of 11 days.)
dude, tritium is not like in the Spiderman 2 movie... its radiation cant even penetrate a sheet of paper.
Now the Energizer bunny will be replaced with the Radiation bunny!
It keeps glowing and glowing...
Actually, you'd keep the battery and buy a new laptop for it every few years.
f u cn rd ths u cn gt a gd jb n cmptr prgmng
There is another way to make a "nuclear battery", which was discussed in the september 2004 issue of IEEE's Spectrum magazine (could not get a link...): by ionizing a bit of matter, it gets attracted to other matter (think static electricity). So you ionize a flat, piezoelectric part that's attached at one end over an unmovable base plate. The attraction makes the loose end of the part strain down to the base, and the piezoelectric nature of the part makes it generate electricity on the way.
You're not old until regret takes the place of your dreams.
This is going to be an interesting thing to see develop over the next few decades. Nuclear power went from this supposed clean and perfect energy source to becoming the demon of nuclear war, chernobyl and three mile island. When you say nuclear power to people, they get images of three-eyed fish, cancer, etc.
Having said that, safe nuclear power, which is entirely feasible right now, is really our best option for dealing with energy shortages in the near future. The pebble bed nuclear reactor technology doesn't melt down, provides copious energy, and doesn't emit a gram of CO2. Plus, if I'm not mistaken, the disposal of the pebbles is less troublesome than the leftovers from the more traditional reactors.
A nuclear battery that could last 10 years would be way better, not only for the users of the batteries, but also for the environment. Think about how much energy you have to use to charge a laptop. All of that energy is primarily coming from fossil fuels. Then when you are done with the battery, you throw it in a dump (at least most people do), and the heavy metals that go into most of those batteries leak into the environment.
Of course, in order for any of this progress to happen, you're going to have to get people comfy with having a radioactive source a few inches away from their crotch. It might have all the shielding in the world, but it's still going to make a lot of people nervous.
This sig has been temporarily disconnected or is no longer in service
anyone else like me fear having anything nuclear in my lap?
You know, I used to worry about it just a little. Thanks to all the propaganda, there was always that nagging concern "What if I get cancer?" But now I'd be perfectly comfortable standing next to a nuclear power plant.
Why, you ask? Because I learned a lot more about radiation and eventually learned that it's not as dangerous as it's made out to be. You see, your body is fending off radiation from everything from bananas, to radon gas that you inhale, to Uranium scattered throughout your back yard, to cosmic rays that come screaming in from space with far more energy than anything naturally occuring here on earth.
Basically, it's a normal risk of living and we deal with it every day. Our bodies are quite well adapted to radiation. (In some cases, people exposed to higher levels of background radiation seem to live *longer*!) Most of the "instant death" or "cancer within months" scenarios involve being swamped with unnaturally high levels of radioactivity. Particularly rays higher in penetration power such as Gamma and X-Rays.
Trust me, a battery that uses Alpha or Beta rays is really nothing to worry about. The radiation can't even penetrate your skin!
Javascript + Nintendo DSi = DSiCade
Yeah, tritium is neat that way. While in US, "frivolous" uses of tritium are banned, in Europe, that's not the case. So, you get things like these neat glowing keyrings that stay bright for a decade.
;) Of course, tritium production requires a conventional fission reactor to produce in quantity (you need to bombard a lithium target, and He3-He3 fusion is neutron-free)
Even air will absorb a significant amount of the tritium's radiation. If the tritium source is right next to you, almost no radiation will penetrate the outer layers of your skin. Even if you ingest tritium-heavy water (so that it can actually do damage), water cycles through your system pretty quickly. The only way you can really get tritium to do major damage without continually reexposing yourself or giving yourself a huge dose is to lock it up in a chemical for which doesn't get lost from the body very quickly and for which the hydrogens don't get interchanged with others often, and then ingest that.
To put it into perspective, ingesting all of the tritium from a gun sight (a common current use of tritium) would be equivalent to about two years of background radiation. In short, while tritium has its dangers, there are a lot of equally dangerous things out there - including what many conventional batteries are made out of.
Interestingly enough, as tritium decays, one product is helium-3 - the stuff that people keep saying we have to mine from the moon, despite its very low concentration there
Stale pastry is hollow succor to one who is bereft of ostrich.
Unlike nucelar reactors which function via nuclear fission, these batteries function by capturing the rays from radioactive materials and converting them into energy.
... didn't Chekov do this in Star Trek IV!?
Ummmm
In terms of increasing amounts of information (least to greatest):
http://en.wikipedia.org/wiki/David_Hahnl b .html
http://www.dangerouslaboratories.org/radscout.htm
http://laplace.physics.ubc.ca/Students/borthwic/r
At least it will also kill off the crabs..
Not a Twitter sockpuppet... but I wish I was.
Depends. Both U-235 and Pu-239 decay via alpha emission, which is easily blocked by almost anything. The risk for detection is beta, gamma, and neutron emission, which the daughter products can release. U-235 is especially bad because not only is its half life 30,000 times slower than Pu-239's, but the principal gamma radiation released in the decay sequence is low energy (a millimeter of lead should be enough to shield most of it).
Purity is important, of course. Your typical reactor-grade plutonium has sizable amounts of Pu-240, which is a lot more detectable. Likewise, if the uranium wasn't created with the intent of making it smuggled, it probably has contamination of U-232, which has a very high energy daughter product decay that wouldn't be realistic to shield. There have actually been proposals to deliberately contaminate all uranium produced (to the extent that international cooperation allows) with U-232 to make smuggling unrealistic.
Stale pastry is hollow succor to one who is bereft of ostrich.
Well, troll is a little strong I think, the concern is valid but should be alleviated with some background knowledge :)
These batteries won't be detected by radiation detectors, anyway. No pulling you off public transport for that.
Not only will the weak beta radiation not get out of the battery, even if the battery does leak, you can pour millicuries of tritium all over detectors, be it badges or geigers or whatever. The weak beta radiation won't even develop film.
Now, medicinal doses of I131 or wahtever- those show up loud and clear. I had a friend who had to have his thyroid zapped- he pegged out lab geiger from 5 feet away.
Weak beta emitters like tritium that are really almost no concern- I'd like it if they were more dangerous as then you can monitor them more easily (they show up on things like a geiger).
The onyl way to "detect" weak betas like tritium is to mix it with some other substance that glows just a tiny bit when hit with low energy beta particles, and then load it into a special very sensitive machine to look for that emitted light.
All that said, I'd like to know if they are loading their battery with millicurie quantities or what- if it leaked, that could be an ingestion hazard. I've not RTFA to see though :)
HTH.
HTH.
I think that you'd have to wrap more than just your testicles, otherwise Chernobyl fall off!