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Atomic Battery

Atomic/solar battery for memory backup
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Take a cube of Tritium-laced phosphors and cover with solar cells to collect the light given off from the phosphor glow. Shield the cube in a small lead case. Tritium has a half-life of about 12 years. It is used in some watches as a gas in small, phosphor coated vials attached to the hands and the quadrants.

Use of other low-grade radiation may improve the shelf-life. The phosphors could be "tuned" spectrally to better match the sensitivity of the solar cells.

OK, it's not a save-the-whales kinda product, but hey...

Darkstar, May 12 2000

Scintillators as ambience gatherers http://www.collimatedholes.com/scint.html
[reensure, May 12 2000]

Alltheweb Search http://alltheweb.co...uclear+batteries%22
Long-baked as a power source for spacecraft [Mharr, May 12 2000, last modified Oct 21 2004]

Betavoltaic http://www.betavoltaic.com/
"Subatomic energy for powering electronic devices and systems." Also developing nuclear batteries. [bristolz, Mar 06 2002, last modified Oct 17 2004]

NurdRage made one… https://www.youtube...watch?v=KKdzhPiOqqg
[notexactly, Mar 22 2018]

…and sent it to Dave Jones of EEVblog. https://www.youtube...watch?v=yNQCaSNIrEM
[notexactly, Mar 22 2018]

[link]






       You'd probably get more energy from the radioactive decay itself than the <relatively> faint green glow if you could catch the particles. Solar cells work by energetic light knocking electrons loose from the silicon substrate <GREATLY simplified, from my memory; may be wrong in detail but is correct in general>. The soft light given off by tritium glow 'modules' doesn't contain enough energy to do that. I don't THINK, anyway...
StarChaser, May 13 2000
  

       "Energetic light"? A photon is a photon; the only issue is the color.   

       That said, internal resistance or something may cause photoelectrics to fail to produce anything at low light intensities. In any case as StarChaser says, it's probably more efficient to try to generate power directly from the radiation (what is it, beta?).
egnor, May 13 2000
  

       X-rays are really high-powered light. Same with say a small lump of lead. If someone drops it on your head, you go 'ow'. If someone takes it and puts it in a piece of pipe with a couple ounces of explosive behind it...   

       If the only issue is the color, why do lasers burn holes in steel when flashlights with a red cover don't?
StarChaser, May 13 2000
  

       Why? Because the photons in a high power laser beam are greater in number and focused by the lense. A photon IS just a photon, and can only do as much as one photon. The differences arise in the amount and focus of the photons.
dontthink, May 13 2000
  

       Mrph. I KNOW there's more to it than just this, but I can't find anything...   

       Ah well, not the first time I've been wrong...
StarChaser, May 14 2000
  

       the other thing about lasers is that all the photons in a laser beam are in phase with one another. which means all their peaks and troughs line up. which means they all hit their target at the exact same time. think of people jumping up and down on a roof. if they all jump at random times, nothing. but if they all jump at the exact same time, they can knock a big hole in the roof.   

       i apologize for that digression. my point was that photons in a laser are in phase.
urbanmatador, May 14 2000
  

       I could have sworn that the 'waves' theory of light (as with the peaks and troughs) was still in early discussion stages. Correct me if i'm wrong, but we really don't know very much about the nature of light.
dontthink, May 14 2000
  

       I live for physics questions at halfbakery!   

       Perceived color of light corresponds to frequency, which corresponds to the energy per photon. (Energy per photon = frequency * Planck's constant.) So the energy of light increases as you move up the spectrum from red to violet. The intensity of light is energy per unit time per unit area = frequency * number photons per unit time per unit area.   

       So StarChaser is basically correct: the photoelectric effect depends on the material absorbing a photon with enough energy to knock an electron loose from its normal orbit, and you don't see the effect at all below a characteristic frequency, which varies from material to material. The rate at which electrons are knocked loose will depend on the intensity of light above that frequency cut-off.   

       (These observations were the ones Einstein used in 1905 to argue that light has to come in blobs [photons] which interact with each other the same way waves do. The nature of light is actually something physicists know quite a bit about --- we've been discussing the wave theory of light since the 1600s, after all! --- and there are many pretty and accurate experiments which conform nicely to theory, as my students could attest. References upon request.)   

       It doesn't seem likely to me that Darkstar's original idea would work all that well; you'd probably get more efficency by using the radioactive material to drive a heat engine.
cosma, May 16 2000
  

       How would this be different than an RTG? http://vraptor.jpl.nasa.gov/voyager/sc_instr/rtg.html Although I doubt you could put an RTG in a watch, they're used in space probes. Basically, the plutonium decays, particles smack the container, heating it, and the tempature differential is converted to electricty by a thermocouple.
rantman, May 16 2000
  

       dontthink, photons are, as far as we know, both waves and particles. they show characteristics of both. in a laser, they show off some of their spiffy "look at me, i'm a wave" skills.
urbanmatador, May 18 2000
  

       Yay! I wasn't hallucinating!
StarChaser, May 18 2000
  

       Mrph. I believe that the key words there are 'as far as we know.' If our knowledge of physics was complete, the field wouln't be so darn exciting right now. However, this is straying from the matter at hand. I have said enough.
dontthink, May 18 2000
  

       This might seem pedantic of me, but I think accuracy is important when dealing with easily misunderstood physics. Photons are not "both waves and particles"; The "wave theory" of light and the "particle theory" of light are just theories. Neither theory claims to describe the exact nature of light; Rather, they are each models of how we can think about light - they each have specific boundaries within which they appear to accurately describe what light does and allow predictions to be made.
hippo, May 23 2000
  

       Assuming you buy QM, light /is/ a wave, and it /is/ a particle, and in fact /all particles are waves/ and vice versa!   

       The issue is that QM is really hard for most of us to intuitively "grok", so people make analogies to the "waves" (as in ocean) and "particles" (little billiard balls) that we have experience with. These analogies are highly imperfect, of course, and that's why we have all these problems ("how can something be both a wave and a particle?").   

       I don't think I'd call these *theories* -- I think a theory is something that someone somewhere thinks might be true. "Models" is a better term. You can model a cow as spherical, and for some calculations it's a reasonable thing to do; for others, it's not, and in any case nobody really *believes* it. Likewise, you can model light as a (billiard-ball-style) particle or an (ocean-style) wave, and each is appropriate sometimes, but neither is true.
egnor, May 23 2000
  

       1) flashlight is powered by a 1.5v drycell and lasers that cut through steel are powered by 1000000v hardlines to the mains. 2) flashlight light is incoherent. It goes all over the place and where ever it feels like, refracts differently, has different freqencies and wavelengths. So it would be hard for a sheet of steel to absorb enough energy from that to start vaporising. A laser beam consists of 'waves' of photons with exactly the same frequency, wavelength and energy.   

       Think of 10 nukes in a row within 1min of each other, or 1000000000 little firecrackers, at random intervals. Which is more effevtive for wiping out new-york?
likwidnarkotix, Nov 20 2000
  

       High-powered lasers do in fact consume more energy than a flashlight, but a "1000000v hardline" is ridiculous. Actual power systems use high current, not high voltage.
egnor, Nov 20 2000
  

       I'm no longer excited about my chosen university course of electrical engineering, and physics. Crap. er... E = hf? F =qVB? *wanders off in haze*   

       Oh, and [egnor] - you've only said half of it - all matter is energy, and vice-versa, and basically, the universe consists of regions of energy, and time is simply a probability sample space for Quantum Mechanics to get their Quantum Overalls dirty with.
Detly, Nov 23 2000
  

       "current" vs. "voltage", egnor?
absterge, Nov 29 2000
  

       betavoltaic: it would be better if you moved your company reference to your profile page. I did add a link to your Web site (above, in the links section) because it is germane to this idea.
bristolz, Mar 06 2002
  

       I didn't think you were grandstanding, at all. Especially after looking at your site.
bristolz, Mar 06 2002
  

       Yeah. Check out these little gems from www.betavoltaic.com:   

       "By linking our stimulated-accelerated isotope decay technology to an energy conversion matrix built on the quantum level we will achieve device efficiencies never before realized."   

       "When you stimulate the release of beta-electrons for power from the subatomic hadronic structure of the neutron and harness it in a device built on the quantum level you have gone just about as far as direct energy conversion technology can go."   

       Methinks these guys must have written dialogue for Star Trek in an earlier life.
karn, May 06 2002
  

       <scouse>
Calm dawn, calm dawn!
</scouse>
  

       Betavoltaic, I don't think he was taking the piss in any spiteful or significant way - just remarking that this stuff went above his head. In a way, you could take it as a compliment - he's saying that you weren't highbrow, like you could have been.   

       As for the copyright stuff - well, chill out. He described it as being from betavoltaic, and wasn't trying to cash in on it, either personally or economically. As such, I don't think he's even infringing copyright (not that I'd swear to it, though).
yamahito, May 10 2002
  

       Looked like an accusation of Treknobabble to me, but it's understandable given that the word 'Quantum' has the same mystic public appeal today as 'Electrostatic' had for the Victorians. It's a real word too, though, denoting a piece of engineering built on a scale that can affect individual electrons. (AKA Beta Particles) This is the kind of scale that virii are built at.   

       Nuclear batteries are a well established technology for deep space probes, using, as Michael mentioned, very high pressure mixtures of radioactive and excimer gases, and it is this pressurisation that makes them too dangerous for commercial sale. If Michael's company has managed to secure rights to an atomic structure that stimulates solid isotopes into performing a comparable trick at less than one atmosphere, then he is the creator of the real-world Shipstones Inc.
Mharr, May 10 2002
  

       Actually, I've taken a recreational interest of late in the websites of technology cranks, especially those in the fields of communication and energy.   

       Somewhere in a discussion of cranky technology I saw Betavoltaic's name, did a Google search, and found both their website and the discussion here. Just couldn't resist quoting those little Star Trekian gems, that's all.   

       I'm well aware that betavoltaic batteries are a real technology that has been around for decades. But that doesn't mean that what Betavoltaic the company claims to have is real. Build a demo, describe and publish the complete principles of operation and let multiple independent testers check it out in their own labs and I'll believe it. Not until then.
karn, May 10 2002
  

       Oh, by the way, I think you'll find that the quoting of small excerpts of copyrighted materials for the purposes of criticism, comment, parody and satire has long been recognized as "fair use" under US copyright law.   

       Regarding your complaint of being quoted out of context, I direct readers to your website at www.betavoltaic.com where they can see the quote I used in its full context and glory.
karn, May 10 2002
  

       I've found that one of the most reliable indications of bogus scientific or technological claims is the "inventor" resorting to bogus legal claims to silence critics.
mab, May 10 2002
  

       Regarding deep space probes, it's news to me that any have used "high pressure mixtures of radioactive and excimer gases". All the ones I've ever heard of use RTGs, Radioisotope Thermal Generators. They consist of nuclear heat sources, usually plutonium-238, coupled to thermocouples on their hot sides, with heatsink radiators on their cold sides.   

       Examples of deep space probes using RTGs include Pioneer 10&11, Voyager 1&2, Viking 1&2 landers, Galileo, Ulysses and Cassini. RTGs were also flown on Apollos 12-17 for the lunar surface experiments. The Soviet Union also flew RTGs on many of their missions.   

       RTGs work on an entirely different physical principle than betavoltaic batteries.
karn, May 10 2002
  

       Thank you, mab. I should also point out that California has an anti-SLAPP statute that allows defendants to recover substantial damages from plaintiffs who sue to stifle legitimate criticism. See http://www.casp.net/cal425.html for the text of the statute.
karn, May 10 2002
  

       Michael, methinks thou dost protest too much.   

       I think you just took care of any doubts readers of this list might have had that you are indeed a crank. You certainly took care of mine. I don't know *what* you're talking about when you say that I've attacked you in every corner of the Internet. My "Star Trek dialogue" comment here was the very first remark I've made anywhere about your company, and I have not made any others in any other public forum.   

       As far as credible proof goes, I think the burden of proof is very much on you and your company to show that you have a real, working technology and not some crackpot pseudoscience that you're palming off to gullible investors. Mab's comment was right on target.   

       As the saying goes, extraordinary claims require extraordinary proof. Either put up or shut up.
karn, May 13 2002
  

       Important addition increases energy output: take the atomic battery with its tritium power source and encase it it a cube of 80 pounds of lead... suspend it from a 20 foot pole and set it into a pendulum motion with a wooden motion converter of daVinci design. Use the additional power output to raise a counterbalanced weight for raising a draw-bridge.
Prof Manitou, Apr 14 2003
  

       From the wikipedia article on Atomic Batteries   

       "An optolectric nuclear battery has also been proposed by researchers of the Kurchatov Institute in Moscow. A beta-emitter (such as technetium-99) would stimulate an excimer mixture, and the light would power a photocell. The battery would consist of an excimer mixture of argon/xenon in a pressure vessel with an internal mirrored surface, finely-divided Tc-99, and an intermittent ultrasonic stirrer, illuminating a photocell with a bandgap tuned for the excimer. If the pressure-vessel is carbon fiber/epoxy, the weight to power ratio is said to be comparable to an air-breathing engine with fuel tanks. The advantage of this design is that precision electrode assemblies are not needed, and most beta particles escape the finely-divided bulk material to contribute to the battery's net power."
vmaldia, Nov 01 2008
  
      
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