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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."
Next time your laptop battery runs out, you get to replace the entire laptop.
-mkb
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.
read post above: tritium radiation is too weak to penetrate human skin. /. crowd.
Tritium does not emit in the gamma range. It emits beta particles (electrons), and neutrinos. Both are harmless to humans, since the electrons are caught to produce current, and neutrinos can go through the entire planet without colliding with a particle.
It's particle physics, but it's not out of the public's understanding. Especially not the
---- I am certain of only one thing : I know nothing else.
It can give energy for 10 years, but if it gets ^^^^ed up, it gives harmful radiation for 100?
Sounds great.
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
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.
If it generates electricity by catching electrons resulting from nuclear fission, then how do you turn it off? Is it always generating electricity? Do you have to have a constant connection to ground so that it can sink any current that's not being used?
Don't these people know anything about marketing. I would NEVER use the word nuclear and tie it into a product. Can't they hire some marketing person to think of a new term? Joe public has know idea what nuclear really is, other than it can blow stuff up or give you cancer.
Consider the following:
You could engineer your batteries to produce significantly more power than the system needs. As the isotope decays, you approach the system's minimum power needs. System alerts you six months before it needs a new battery.
You could design a hybrid battery--part traditional power storage, part nuclear generation. As the traditional battery is drained, the nuclear battery charges it; best of all, when you're not using the laptop, it charges by default. You wouldn't need a nuclear battery big enough to run the whole laptop--just big enough to stretch that five hour standard battery to a ten-hour battery, with the added bonus of automatic, cordless recharging when the system isn't in use...
Obliteracy: Words with explosions
Buy a smoke detector. Those have radioactive materials in them. Wasn't it on /. a few years ago that there was a story about a kid making a mini-reactor in his backyard shed out of tritium from gun sights, and whatever the material is in old smoke detectors?
About 25 years ago, I bought a very inexpensive digital watch that was 'glow-in-the-dark'. On the back was a radioactivity symbol that indicated the watch contained 200 mCi of 3H. As a molecular biologist who became very very careful when working with 5 mCi of 32P (a much stronger emitter) or 3H-thymidine, the idea of wearing 200 mCi of 3H seemed quite exciting.
Indeed, I believe there was a superfund site due to 3H contamination from watch manufacturing.
As cool as this sounds, I really doubt we'll see these things at the consumer level even when they are ready.... This will KILL the current battery market, and I'm sure Energizer and Duracell will do anything and everything to stop these from killing their business....
The Digital Couture Collection
Beta-radiation? Only lethal if inhaled? Then why didn't you say so, guy? That's so awesome, these'll get rid of engergizer bunnies everywhere!
Except that tritium is helium, and helium is usually a gas in the conditions we live under. Their design specifications confirm the use of a circulating radiative gas. If this thing even so much as cracks during its ten years in operation you will end up with a god-aweful fuming battery of death. It's a great idea, but I would never feel comfortable around them.
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.
If we can turn radioactivity into electricity, can't we build generators around toxic nuclear waste?
There's always been a good market for tritium. Lithium targets are deliberately added to nuclear reactors to produce it.
;)
Find a large enough market for strontium-90, iodine-131,133, caesium-134,137, tellurium-132, strontium-90, etc, and then we'll be in business
Stale pastry is hollow succor to one who is bereft of ostrich.
There was that kid, but if you want to go fusion, you might look at these people.
One line blog. I hear that they're called Twitters now.
Sad to say the first nuke to destroy a city in America will probably get there without being checked as they'll just send it UPS or Fedex
ACs don't waste your time replying, your posts are never seen by me.
Of course, once somebody tosses one into an incinerator then the tritium will be directly released into the environment as radioactive H20, which is highly dangerous and doesn't need to penetrate your skin. Any nuclear battery with enough power to power a laptop (~20W) will contain a significant amount of total radioactivity, which would be a major concern if the battery were incinerated or corroded in a landfill. Therefore, you will never see these on the consumer market.
Moreover, tritium has major WMD issues. All modern nuclear weapons use tritium to boost the fission core; it allows bombs to much more efficiently use their fissile fuel and provides a much more consistent yield. Currently, the world supply of tritium is tiny, and much of it is carefully hoarded by nuclear-capable states to keep the tritum boosters in their warheads replenished as they naturally decay. The powers that be will want to keep this key weapons material hard to obtain; this is another reason that governments are never going to allow significant amounts of tritium to be handled by the general public.
If it's hard to get this stuff, why it is used in watches and exit signs?
Hmmm well it my A level physics is anything to go by (i did it in the last 20 years so probably not) beta radiation is high energy electrons, and 3mm of aluminium will stop them. They are bad for your health, but it takes time, usually.
Alpha particles are helium nuclei (2 protons, 2 neutrons), these are stopped by your sheet of paper. They don't penetrate skin...
then your gamma rays are not stopped by lead and are very bad.
I spent some summers working in a government lab with tritium.
Interestingly the recommended procedures in case of a tritium leak was to drink as much coffee and beer and water as you can, to cycle the water faster. Sounds just like college.
At first I figured the output, while long lasting, would just be too low to be useful. I went to beta-batt's website, got the numbers and did the math. These batteries are surprisingly good.
The first-gen tritium ones (and tritium ones is probably all we'll ever see in commercial applications) put out 400 microwatts per cubic centimeter of nuclear battery volume, half-lifing at 12 years of course.
Based on various data I pulled from Energizer's website and Betabatt's website, it comes out like this:
A regular AA-sized NiMH rechargeable battery (2,500mAh @ 1.2V) can be recharged by a nuke battery of identical volume (picture a companion Nuclear-AA battery next to it) from empty to full in roughly one month. Or five AA-sized nuked batteries could recharge a normal NiMH AA in a little under a week. In either case, that's for years (obviously, the charging rate gets slower as the years go on).
Even in that form, it's quite useful. Assuming linear scalability in both regular and nuke batteries, that means if you have a device which can last up to two months on a rechargeable battery of some size, you can stick a nuke-charged of equivalent volume to your battery next to it, and between the two of them your device will stay continuously powered for at least 12.3 years.
Imagine when the next generations come out and get more efficient. I can't wait. For useful largish devices you'll always need a chemical battery for bursty amperage, but have a nuke-batt as a recharger is so handy.
11*43+456^2
Into a Lithium Polymer surge battery of course. You can't expect these to provide enough power on their own to power a device, but they'd be great for trickle charging another battery. Think about it, your cell phone lasts a few days on a little Lithium Ion or Lithim Polymer battery, but if your replaced half of that battery with one of these nuclear batteries then it would constantly charge it. Instead of 4 hours of talk time you get 2 hours, but probably indefinite standby time, and after a while of not using it your 2 hours of talk time is back. ::
It's the basic problem that capacitors were invented to solve! The capacitor in this case just becomes another battery.
You could design a hybrid battery--part traditional power storage, part nuclear generation. As the traditional battery is drained, the nuclear battery charges it; best of all, when you're not using the laptop, it charges by default. You wouldn't need a nuclear battery big enough to run the whole laptop--just big enough to stretch that five hour standard battery to a ten-hour battery, with the added bonus of automatic, cordless recharging when the system isn't in use...
Lithium batteries require about as much voltage to charge as they give off during operation. If the radioactive battery can't deliver enough power to power the laptop, it won't be able to deliver enough power to charge the battery.
Oh, a lesson in history from Mr. I'm my own grandpa.
I wish I had one of those keychains do test this out myself! I have a pancake ludlum too!! :) It's not that I doubt your claim, it's just that it is IMPOSSIBLE for the 18KeV (max) betas from H-3 to escape the glass capsule. Either you are detecting radiation from the glass itself (not an uncommon phenomenon) or you are detecting the X-rays (bremstrahllung) from the deceleration of the betas as they slam into the glass.... OR...could the phosphor be a rare earth (Eu?) variety with some leftover contamination from the separation process? (wild guess)
- "Hear that?! The percolations are imminent! Cease your ingress!"
Lithium batteries require about as much voltage to charge as they give off during operation. If the radioactive battery can't deliver enough power to power the laptop, it won't be able to deliver enough power to charge the battery.
If you can charge them in pulses then it's not a problem. The flash tubes in disposable cameras take a few thousand volts to trigger but are usually powered by a single 1.5V battery.
Boosting a gun-type device with tritium is a pretty mighty task. Where would you put it? Into the pit? Won't do much good there. You'd have to inject it there very quickly before the assembly, or it'd soak into the metal and you'd get hydrogen embrittlement issues.
Tritium is useful for the implosion devices, and even there you can do without; and making enough tritium is easier than making enough plutonium.