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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.
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.
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?
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.