Sciencemadness Discussion Board - Why no nuclear batteries in cell phones ?

Why no nuclear batteries in cell phones ?

metalresearcher - 26-10-2011 at 09:52

The current generation of batteries in cell phones cannot keep up with the consumption of the smartphones like the iPhone or Samsung Galaxy. One has to charge it eveery day.
I know that pacemakers have a (very small) plutonium cell in it to power it, despite this it is completely harmless as it iis implanted into the body.
Why are cellphones or tablets not equipped with such a RTG or other kind of nuclear battery ? Aside from Pu , some other rsdioisotopes are used such as Tc-99, Pm-147, Po-210.
In the case of Pu-238 is is a way of diisposing of all old nuclear bombs.

AndersHoveland - 26-10-2011 at 10:11

Scientists, industry, and society were formerly a little overenthusiastic about the potential of nuclear energy. Now they err too much on the side of caution. But alpha-emitting isotopes can be formed into a glass for relative safety against the possibility of rupture/contamination. Thermocouples are not an efficient method of generating electric current, a typical pacemaker generated only 300 micro Watts of electric current. It is to be suspected that a nuclear battery would be too bulky to deliver the required power output to a mobile phone. Another idea would be to have the nuclear battery power a small conventional battery in the phone. The battery could simply recharge itself after a period of inactive use.

dann2 - 26-10-2011 at 11:57

Are you joking.
You could take your 'glassy substance' and dissolve in Hydroflouric acid (other too perhaps) and bingo...
I could see some 'charity' begging for used moblie phones for poor folks way out in foreign lands.

hissingnoise - 26-10-2011 at 12:06

Quote:

In the case of Pu-238 is is a way of diisposing of all old nuclear bombs.

Or a novel kind of trickle down technology with needy Pashduns as beneficiaries?

Polverone - 26-10-2011 at 13:04

Cost per watt-hour supplied is much higher for RTGs than for chemical batteries.
RTGs are much bulkier than chemical batteries for the same peak power output.
Unlike pacemakers, cell phones could easily be chemically or mechanically disassembled by curious owners.

No nuclear fuel reprocessor is interested in turning its carefully managed waste streams into low-value, widely dispersed consumer products. Should a crazy man be appointed CEO, he will still be barred from offering the iRAD cell phone battery by regulations governing hazardous radioactive material. Note that the isotopes usable in RTGs are all extremely radiotoxic: if they were long-lived and relatively harmless, they couldn't supply useful power.

AndersHoveland - 26-10-2011 at 14:04

I think there are too many government regulations in our societies. Use of radioisotope in consumer products should be encouraged. Small quantities of plutonium in a glass form, within a protective metal casing would pose no unreasonable hazard. Trying to collect enough used mobile phones to obtain a sufficient mass of plutonium would simply not be economical. There also exist classes of fluoride glass which are resistant to attack by hydrofluoric acid.

Although Plutonium-238 has been used in radioisotope batteries, the more common form of the element is plutonium-239, which would not be very suitable for use as a battery since it has a half-life of 24,110 years, meaning it would have too low of a heat output. Unlike Pu-239, Pu-238 is generated by bombarding uranium-238 with deuturium ions. So the idea of directly harvesting plutonium waste from nuclear reactors to make batteries is not as feasible as it may first appear.

phlogiston - 26-10-2011 at 16:17

You are ignoring many things that explain why nuclear batteries are impractical. Just a few of the more obvious in random order:

1. The amount of power used by mobile phones is thousands of times higher than a pacemaker uses. The amount of nuclear material needed is correspondingly higher.

2. If you consider that a 300 microwatt pacemaker Pu-238 based battery costs over USD 3000,-, imagine the cost of a battery that could power a mobile phone

3. The potential for misuse is enormous, even if a non-fissile isotope is used

4. The battery will outlast your phone's lifetime 100's of times over (and may even outlast yourself for that matter, depending on the isotope used)

Each of these things easily outweighs the slight inconvenience of having to recharge your phone every so often.

[Edited on 27-10-2011 by phlogiston]

unionised - 27-10-2011 at 10:02

"In the case of Pu-238 is is a way of diisposing of all old nuclear bombs."

Or vice versa.

stygian - 27-10-2011 at 12:47

Pu-238 is said to be unsuitable for such bombs. Maybe I just misunderstood you though?

AndersHoveland - 27-10-2011 at 13:02

Quote: Originally posted by phlogiston

The amount of power used by mobile phones is thousands of times higher than a pacemaker uses. The amount of nuclear material needed is correspondingly higher.

Very much to the point.

As I see it, the main problem is finding a more efficient method to convert radioactive decay into electric current, and such a device needs to be small and compact. There do exist several radioisotopes with appropriately short half-lives (and thus enough energy output) to potentially power a mobile phone.

As previously mentioned, such nuclear generators would likely need to be coupled with a conventional battery, because any radioisotope with enough power output to directly power a phone would be extremely hot. Since there is no way to "turn off" this heat, it would likely be extremely inconvenient inside a mobile phone, which typically rests in ones pocket. The nuclear battery could slowly generate power to recharge the chemical battery while the phone was not in use. Another potential possibility might be to find a means to directly convert the radiation into microwaves, which could then be modulated. Avoiding intermediate conversion into electric current could greatly increase efficiency. Since most of a phones power output goes to generating a microwave signal, this method would directly solve the main problem.

phlogiston - 27-10-2011 at 14:29

Current RTG efficiency is in the range 3-7%. Even if this could be improved to an unlikely 50%, well beyond any theoretical possibility currently thought possible, and peak demand would be handled by a battery like you described, I think one would still need 10's to hundreds of Curies depending on the isotope. Cost, shielding, security and disposal/recycling would be a costly nightmare.

Converting alpha/beta/gamma radiation directly into any microwave signal, let alone a clean, well modulated complex signal, is pure imagination. Any basis for this?

AndersHoveland - 27-10-2011 at 14:48

Quote: Originally posted by phlogiston

Cost, shielding, security and disposal/recycling would be a costly nightmare.

Cost would be much less of an issue if government regulations were relaxed down to Russian or Chinese levels.

For radioisotopes that decay only through alpha decay, a cm of sheiding would be sufficient. The generator could be placed in the center of the phone so that the surrounding electronics would act as the shielding. Many of you seem to be worrying to much about supposed "dangers". There is no reason to be irrationally paranoid. As for the potential of "terrorism", I think this is completely ridiculous. Stop being such worry-mongerers! Just because it involves a "radioactive" substance does not mean the idea should immediately be discounted as "too dangerous". The radioisotope could be sealed in a benign form inside an impenetrable container, with an adequate warning on the outside, just as with any other potentially dangerous consumer product.

Quote: Originally posted by phlogiston

Converting alpha/beta/gamma radiation directly into any microwave signal, let alone a clean, well modulated complex signal, is pure imagination. Any basis for this?

Future technology might enable this. In principle at least, the conversion should not be too difficult. Beta particles (electrons) from the radioactive decay could simply be lead directly into a resonance cavity to generate the microwaves.

[Edited on 27-10-2011 by AndersHoveland]

Mr. Wizard - 27-10-2011 at 15:24

@ Anders Hoveland You don't seem to understand the risk of radioactive isotopes. It isn't just the emitted particles or electromagnetic waves that are dangerous. For example you mention alpha emitters, as 'only requiring 1 cm of shielding should suffice. Let's pretend that the radioactive isotope is one of Polonium's 33 possibilities.
http://en.wikipedia.org/wiki/Polonium
The alpha emissions could easily be stopped, but how do you stop the material from being accidentally or purposely released to the environment? Once the source material is outside the shielding and floating as dust , it is free to lodge itself in your lung tissue, the pasta on your plate, or into the sharp edge that just broke your skin when you stumbled and fell. Once inside, your body is receiving the full dosage. Yes the travel of an alpha particle is only millimeters, but that's far enough to disrupt a cell's nucleus. The inverse to the short travel distance of alpha particles is their extreme disruption as they are very charged ++. This rips electrons off every chemical bond it travels by. It is like a car hitting a crowd of people.
In ignorance people tend to discount the danger of alpha radiation because it can be stopped by a piece of paper. Nothing can be farther from the truth, the ingestion of alpha emitters is very, very dangerous.

AndersHoveland - 27-10-2011 at 15:39

Even dangerous alpha emitters are rendered relatively benign in an inert glass form. A particle of glass may even be swallowed, that the radioisotope will still not be absorbed into the body. The radioisotope glass could then be safely stored inside a strong (but lightweight) enclosure that would be resistant to tampering. A beta emitter might be more appropriate.

Mr. Wizard - 27-10-2011 at 15:59

Quote: Originally posted by AndersHoveland

Even dangerous alpha emitters are rendered relatively benign in an inert glass form. A particle of glass may even be swallowed, that the radioisotope will still not be absorbed into the body. The radioisotope glass could then be safely stored inside a strong (but lightweight) enclosure that would be resistant to tampering. A beta emitter might be more appropriate.

Let me speculate how long it would take to render just about any type of glass into a fine powder. In a few minutes, with a hammer and steel plate I would have dust that would certainly poison me, while I was making it. Given 48 hours and a rolling mill used to make Al dust, I could have converted your whole power supply to air float.

My job here is not to convince you, it's just to make my point or idea clear. Good luck with your idea.

dann2 - 27-10-2011 at 18:52

Could be doin with some Polonium 210 for the mother-in-law meself............

http://en.wikipedia.org/wiki/Alexander_Litvinenko

Dann2

Intergalactic_Captain - 28-10-2011 at 05:46

I've often pondered this one myself, considering the idea that one might be able to create a future-proof battery. However, after reading some of the comments here, I can see a few legitimate (and freaky) reasons that it hasn't happened. Just for the sake of something to visualize, could someone here do the quick math on just what it would take to power an iPhone on such a baterry? As in the size of the battery at modern efficinencies and the necessary shielding? I could give a shit about smart-phones, but nuclear physics ain't my thing and I'm sure the numbers would be mind-boggling...

...The more paranoid comments remind me of something I saw a few years ago over at the pspmod forum - When the Pandora tools came out, one of the necessary steps was cracking open the battery and shorting/cutting a couple pins on its control board. This is piss-easy if you have any fine motor skills. Yet, every day, someone on the forum would post something along the lines of "I slipped and cut that silver foil thing - can I just tape it back up?" The silver thing is the foil "pouch" that is the li-ion cell itself. Every thread I found, I went on a tirade about how it doesn't work that way - Yet still, others were stating that taping it back together was perfectly fine. Then they wondered why their batteries stopped working, started smoking, or straight-up caught fire...

Moral of the above? The average consumer is a fucking idiot. Added to that, the "hackers" these days are perhaps 5% knowlegdable, 85% stupid, with the remaining 10% or so realizing that they should figure out what they're doing before the do it. As much as I hate to say it, if the average idiot can't figure out that li-ion batteries are more complicated than roll of duct tape, the market isn't ready for nuclear batteries.

Polverone - 28-10-2011 at 11:14

Quote: Originally posted by Intergalactic_Captain

Just for the sake of something to visualize, could someone here do the quick math on just what it would take to power an iPhone on such a baterry? As in the size of the battery at modern efficinencies and the necessary shielding?

The iPhone 4s has a factory battery capacity of 5.3 watt-hours. I don't know if this number represents the useful battery capacity or the total battery capacity; that is, the point at which no more current will flow or the point at which the voltage drops too low to operate the iPhone. I'm going to assume all 5.3 watt-hours are usable.

The iPhone's shortest battery life is found recording video. It will exhaust its battery in 2.3 hours during video recording. This is a power draw of 2.3 watts.

To get 2.3 watts out of a 7% efficient RTG based on Pu-238 as plutonium dioxide, it will take 67 grams of plutonium dioxide to provide the thermal energy. As of 2000, that much Pu-238 would cost about $18,000. I understand that Pu-238 costs have gone up since; Russia now is an effective monopoly provider of Pu-238. I will leave it up to others to estimate how much additional weight and bulk are added by the thermocouples, shielding, and any tamper protection you want to add.

Keep in mind that the battery is now an external device that cannot comfortably go in your pocket regardless of shielding: it continually dissipates about 33 watts as heat, whether the phone is in use or not.

Endimion17 - 1-11-2011 at 21:45

Quote: Originally posted by AndersHoveland

I think there are too many government regulations in our societies. Use of radioisotope in consumer products should be encouraged. Small quantities of plutonium in a glass form, within a protective metal casing would pose no unreasonable hazard. Trying to collect enough used mobile phones to obtain a sufficient mass of plutonium would simply not be economical. There also exist classes of fluoride glass which are resistant to attack by hydrofluoric acid.

Although Plutonium-238 has been used in radioisotope batteries, the more common form of the element is plutonium-239, which would not be very suitable for use as a battery since it has a half-life of 24,110 years, meaning it would have too low of a heat output. Unlike Pu-239, Pu-238 is generated by bombarding uranium-238 with deuturium ions. So the idea of directly harvesting plutonium waste from nuclear reactors to make batteries is not as feasible as it may first appear.

So the only danger from plutonium is making atomic bombs? Of course, plutonium dioxide is easily transformed into a working atomic bomb...

Are you serious? Are you really serious?

"Impenetrable container"? Really? Made of what?

It's because of guys like you that I actually feel better knowing there are repressive governmental systems that watch the spread of certain radioisotopes. When I was a kid I thought it would be cool to obtain some plutonium salts, but now when I'm grown up I'm glad the regulations are strict.

Do yourself a favor. Check out the Web for Goiania accident and Mayapuri accident.
And do some studying on radioisotopes and radioactivity because it seems like you downplay the dangers of it to the level of "funny glowing stuff".

[Edited on 2-11-2011 by Endimion17]

AndersHoveland - 2-11-2011 at 14:26

You do realise that the toxicity of solid metal plutonium-239, when ingested, is essentially the same as that for ethanol ?

Although the toxicity of plutonium dust in the lungs is much higher. The main threat to humans comes from inhalation.

Ingestion is not a significant hazard, because plutonium passing through the gastro-intestinal tract is poorly absorbed and is expelled from the body before it can do harm. In the 1940s some 26 workers at US nuclear weapons facilities became contaminated with plutonium. Intensive health checks of these people have revealed no serious consequence and no fatalities that could be attributed to the exposure. In the 1990s plutonium was injected into and inhaled by some volunteers, without adverse effects. In the 1950s Queen Elizabeth II was visiting Harwell and was handed a lump of plutonium (presumably Pu-239) in a plastic bag and invited to feel how warm it was.

http://www.smartplanet.com/blog/science-scope/plutonium-is-1...

Endimion17 - 2-11-2011 at 17:49

First of all, RTGs do not contain metallic forms of radioisotopes. Metallic plutonium is a serious fire and radiological hazard. When that shit starts oxidizing and flaking off, you know it's Chernobyl time.

RTGs contain ceramics, and plutonium dioxide is a ceramic. I'm not sure whether sometimes they mix it with other oxides, but I'm sure there's no metal inside.

I know about the toxicity of plutonium, and the myth that was generated around it. It is most certainly not the worst poison in the world, but it's mighty dangerous even if it's in a nonpyrophoric state.
Chemical elements, radioactive or not, are mobile in environments. Plutonium is usually not very mobile, but we are. Our hands, the sweat, dust, air, bacteria, etc.
Put a cubic milimeter of its dioxide on your shelf behind the book and in half a year I guarantee you'll have readings in your backyard. Probably not alarmingly high, though your room would be very contaminated.

AndersHoveland - 3-11-2011 at 15:57

Let me make this clear: A glass material composed partly of Pu-239 oxide would essentially be no more hazardous than a vial of mercury. Pu-239 has a very long half-life so it is not nearly as radioactive as many other radioisotopes. The radiation from a solid piece of Pu-239 is simply not a safety issue.

The real issue is preventing the plutonium from transforming into a hazardous dust, which could be inhaled by the lungs.

Mr. Wizard makes an excellent point that the glass could be intentionally crushed into a fine powder to release hazardous plutonium-laden dust:

Quote: Originally posted by Mr. Wizard

Perhaps there is some other method of rending the plutonium inert? Perhaps in the form of a corrosion resistant alloy? One that could not be easily chemically dissolved? I am sure there must be some sort of low cost alloy that would resist aqua regia. Or possibly the Pu-239 could be chemically absorbed into a silicone polymer? The polymer would ideally be able to withstand intense fire without vaporizing.

But we are not really discussing using Pu-239 in an electronic device. Any radioisotope that generates enough energy output would also be dangerously radioactive.

[Edited on 4-11-2011 by AndersHoveland]

Endimion17 - 3-11-2011 at 17:32

I'm not talking about the radiation. It's rather benign in new samples, but older samples are worse because its decay daughter nuclei are more unstable.
I'm talking about plutonium's radiotoxicity. Yes, a nicely prepared RTG does not pose a threat. It's just nicely warm. But if someone wants to do some extremely nasty things with it, success is guaranteed.

Evil people exist, and they do evil stuff. This is completely unrelated to the "guns and knives availability".
Making plutonium dioxide available in macroscopic quantities to the general public is releasing the dragon from the cave. Dragon worse than any gun or knife.
Sooner or later someone's gonna turn the shielded material into a deadly form and disperse it. It might be just out of pure stupidity because stupid people doing stupid stuff exist, too.

Make it available and few months from the date it appears in stores you'd start to pick it up with a sensitive counter in the local city streets. Few months more and someone will try to make the pure metal. It will catch fire and make an aerosol. Death from lung cancer gets highly probable for the neighbours.
Around the same time someone is going to experience an excursion burst in his shed because he piled up too much of it in one space. Blue flash, melting (or first boiling of the solution), vaporizing. Walking ghost phase, gruesome death. Cancer starts to appear in the nearby blocks.

That would happen few times per each million of people. At least.
In the following years, a global cancer rate would increase. Simply because people would disperse it (evil, stupid or just too clumsy for plutonium) and the fact atoms are small.
And then some moron would make a dirty bomb, or a real nuclear bomb that would of course fizzle (because nuclear detonation is something extremely difficult to accomplish) and create a new Chernobyl-like area.

Plutonium is not dangerous at all if handled properly, but if you mess something up, it will fuck you up, and fuck up others. In the ass, mouth and every orifice with a spiked, rusty and monstrously huge steel dildo.

Its potential for fucking something up is unbelieveable, orders of magnitude worse than mercury, thallium, cadmium.
It's supposed to be unavailable, locked in institutes and guarded. There's a reason for it, and it's not a conspiracy. Just citizen safety.

Americium is available in microgram quantities and we all know what that Hahn dude did. I'm sure he's not the only one.
Provide plutonium compounds in hectogram amounts and this world would become a leaking nuclear wastedump.

[Edited on 4-11-2011 by Endimion17]

AndersHoveland - 3-11-2011 at 20:05

You do realise that anyone with a little knowledge about high voltage electronics and metal refining could make plutonium? All one needs is a Farnsworth fusor and some yellow cake uranium to get a miniature breeder reactor going...

http://www.bbc.co.uk/news/10385853

Thiago Olsen, a 17-year-old in Michigan, also built a fusion reactor:

http://www.bit-tech.net/news/hardware/2007/03/28/homemade_fu...

http://www.fusor.net/board/download_thread.php?bn=fusor_neut...

[Edited on 4-11-2011 by AndersHoveland]

Endimion17 - 4-11-2011 at 05:00

Yeah, at what rate? That's just ridiculous.

AndersHoveland - 4-11-2011 at 21:11

Actually, some of those fusors can put out a fairly high neutron flux, even to the point of being hazardous.

madscientist - 4-11-2011 at 22:53

Quote:

Now they err too much on the side of caution.

The explosions in Japan said otherwise.

Quote:

Use of radioisotope in consumer products should be encouraged.

Someone has been reading too many old 1950s Popular Science magazines.

Endimion17 - 7-11-2011 at 10:23

Quote: Originally posted by AndersHoveland

Actually, some of those fusors can put out a fairly high neutron flux, even to the point of being hazardous.

Neutron radiation becomes dangerous at fluxes much lower than it takes to do a transmutation at an effective rate.
When radioactive isotopes are made, for example for medical use, they're put in an intensive neutron flux in a reactor and it takes some time to finish the job i.e. to get a dilluted sample of a wanted isotope.

Quote: Originally posted by madscientist

The explosions in Japan said otherwise.

Plutonium was found in traces detectable with special counters that can calculate the energy of the rays and therefore determine what's likely to be the source.
The amounts were very small and didn't represent any threat to anyone.

Caesium and iodine, that's a different story. They're volatile as we consider power plant premises, and quite mobile in biosphere. The cumulative leak of the whole plant probably really exceeded the leak from Chernobyl. Luckily, the wind was blowing mainly eastward, towards the sea.