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View Full Version : New atomic battery = awesome



Gullible Jones
2005-Dec-15, 10:54 PM
Time to kiss them radiothermal generators goodbye. (http://www.sciencedaily.com/releases/2005/05/050514205902.htm) I'd heard something about research on high-yield betavoltaic batteries before, but this is the first time I've seen it hit the news with a big success story.

At any rate... This thing is awesome. And tritium is a gas, these things could be rechargable!

(I wonder if a radon-powered one would be possible? The energy yield might be higher... But alpha radiation isn't as penetrating, so the layer that generates current would probably have to be thinner. And radon is definitely rather dangerous stuff than tritium...)

LurchGS
2005-Dec-15, 11:02 PM
so long as the container is sealed, should be ok

The Supreme Canuck
2005-Dec-15, 11:20 PM
Yeah, tritium's pretty bad if you inhale it as well. But there's so little of it in such things that it wouldn't be a big deal.

LurchGS
2005-Dec-15, 11:39 PM
that was my thought! give it back!

besides, which is worse? no heartbeat, or the possibility of cancer some years down the road?

Gullible Jones
2005-Dec-16, 12:06 AM
Wait, who said pacemaker...? Oh, yes, that was suggested.

No, I'm thinking of something along very different lines. Space suits, deep-sea ROVs that could stay down for years, all kinds of neat stuff. But using these things in the human body seems rather stupid.

(Hmm... Aren't they atomic fuel cells, really, as opposed to batteries? They can't be recharged, but they can be refueled.)

eburacum45
2005-Dec-16, 12:46 AM
Well, they are nuclear power generators, really;

but if they use tritium, they are using an isotope not generally found in nature, so perhaps the energy used in producing the tritium (from lithium) has to be taken into account.

TheBlackCat
2005-Dec-16, 01:27 AM
But using these things in the human body seems rather stupid.
Why? There is a great need for long-lasting power sources in biotechnology.

The question I have is regarding lifespan. The human body is one of the most inhospitable environments known to man for any sort of machinery. I am not saying we don't, but we need to make sure we the materials and manufacturing techniques to build a battery casing that can last 10 years in the human body with 100% reliability. I am not aware of an implanted medical device that operates reliably for more than 15 years. And if someone's total hip replacement comes loose they will know it and get it fixed. If a tiny leak develops in your pacemaker battery you probably won't until it is much too late. It wouldn't have to be enough to seriously hamper the device's effectiveness, just enough to release very low levels of the gas into the body cavity. Current lithium-ion batteries technology is expected to last about 5 years, only 1/2 the expected lifespan of this new battery. Are we really sure enough about our biomaterials knowledge to make it worth one relatively minor surgery? I could understand something that would help with a massive and extremely difficult surgery like replacing a joint or implanting a cardiac assist device, but batteries are placed somewhere easy to get to and relatively unobtrusive because the doctors know they will have to replace the battery eventuall and they set things up to make that as easy as possible.

The Supreme Canuck
2005-Dec-16, 02:38 AM
I don't see a safety issue with implanting it. They've sold these (http://www.bookofjoe.com/images/glowringslit.jpg) for years. Filled with tritium, coated in phosphor. They're also used for emergency lighting. As long as they don't break, there's no danger at all.

LurchGS
2005-Dec-16, 04:02 AM
I think BC is thinking along the lines of the hooyaw that arose from the 'leaking' breast implants... *if* one of these batteries were to leak, it would be bad... but I don't know how much tritium gas is in there.

I would think: not enough to be seriously dangerous in the short term.

So... battery leaks... equipment stops working... patient trots down to OR and gets it replaced.. any damaged tissue is excised and away he goes

----------------

and his heart went whirrrr-click, whirrrr-click

The Supreme Canuck
2005-Dec-16, 04:13 AM
Hm. What may actually be a problem is that the gas would remain trapped in the patient's chest. It can't dissipate. That could cause problems.

But then any impact that can rupture the battery is going to rupture you long beforehand, so the point may be moot.

LurchGS
2005-Dec-16, 04:17 AM
but if it corrodes/leaks?


in any such event, though - the patient would soon be in the hospital - I don't think any trapped gas would stay that way.

TheBlackCat
2005-Dec-16, 04:49 AM
The issue with breast implants is even if they do leak, which is relatively common, silicone is one of the most biologically inert compounds known to man (probably right up there with titanium and PMMA). It is simply harmless, the implant has to be replaced and the silicone removed but since it is largely trapped in area around the implant that is a relatively minor concern.

The problem is, in the human body, it is not a matter of if it leaks, it is a matter of when. There is no such thing as a completely biocompatible material. With a pretty much inert substance like silicone that is not a big deal, but with a radioactive gas the issues with leakage are more serious. So the real question becomes, which will happen first: the battery runs out of power and gets replaced or the battery leaks. If it is the former within a very large degree of certainty than the batter technology is a good idea. If it is the latter, the issue becomes a bit more complicated since the effects of the tritium (which I am not familiar with) and the danger associated with battery failure for a particular device will have to be taken into account. If the batter can only be expected to work 5 years before failure, there is really no benefit to be had from a battery that runs for 10 years over the modern batteries that run 5 if it is replaced at 5 years anyway in order to pre-empt a possible disasterous failure (a common tactic in implant technology). Remember, this is not like a CD player that you use until it breaks or you get a better one. If a implant fails, people can die. They usually go in and try to replace critical implants before they fail in order to prevent this. Now I do not know if what the lifespan of batteries are, and it certianly varies depending on application, I am simply saying that having a battery that last for 10 years is not necessarily better than one that runs 5 when it is implanted in the human body.

LurchGS
2005-Dec-16, 04:55 AM
I am simply saying that having a battery that last for 10 years is not necessarily better than one that runs 5 when it is implanted in the human body.

oh, in that respect, I agree. On the other hand, I'm not sure things like titanium or stainless steel corrode significantly inside the body - significantly enough to eat through the battery shell, anyway.

TheBlackCat
2005-Dec-16, 04:58 AM
No, but then the battery shell isn't the issue. There has to be places where the wires enter the battery, there has to be joints where the two haves of the shell are joined, the wires themselves are hollow so if they break fluid can get into them that way. The shell is not the weak point, there are a number of holes in the shell that could act as potential routes by which fluids could get inside the battery and start corroding and breaking down stuff.

LurchGS
2005-Dec-16, 05:02 AM
valid concerns, but beatable, I think, if need be

wayneee
2005-Dec-16, 05:14 AM
I just hate batteries in general, caustic chemical reactions to create electricity. Too easy to produce to ignore , but just too toxic to tolerate.
Pacemakers have been around so long sometimes it seems that folks believe thats the best we could do . I have wondered if we could harness the same energy produced by Mitochondria ,via the citric Cycle, using the same cells from the patient we could make a BioBattery. I can sense The Black Cat bristling

TheBlackCat
2005-Dec-16, 05:38 AM
People have been trying to make devices that run on biological molecules for a while. It has proven to be very difficult. Biological molecules are set up so they can be used in a very controlled manner in extremely efficeint, very small enzyme-driven reactions, reactions that are set up to be controlled down to the single-molecule level in many cases. Human devices, to put it bluntly, are not. Humans devices are made to use large-scale, extremely inefficient reactions for power. It has proven very difficult to get human-built machines to run even on highly refined biological fuels like sugar cubes. It has been done, but not particularly well. Human technology and biology have completely different scales of operation and extremely differnt goals for what their power sources would do, biological fuels are simply do not have the chemical proprties that would make them effective power sources for human technology. Similarly, attempts ot build a power source that uses biological reactions, called microbial fuel cells, only produce extremely small amounts of power in relatively bulky devices. They are nowhere near effective enough to be practical. So although it is a lofty goal, one that it seems a significant amount of work is being put into because of the natural advantages of such methods in many applications, it has proven to be extremely difficult.

IsaacKuo
2005-Dec-16, 06:12 AM
What's the power/weight ratio like for these things? I'm wondering whether they'd be good for long term SLOCUM submarine gliders. Right now, they're battery powered for short duration missions and thermocline powered for long duration missions. Thermocline power is very weak, though. Would this type of battery be competetive?

TinFoilHat
2005-Dec-16, 02:06 PM
On the website http://www.betabatt.com/ it claims that these batteries have "about the same energy density as a lithium battery". If true, then this is a truely underwhelming technological development. If the energy density is only as great as existing battery technology, what's the point? If their cells have about the same power density as a lithium battery, but a 10+ year lifespan, that would be a different matter entierly.

What I would really like to see is a radioisotope power source with a power density great enough to power a vehicle. If it could be mass-produced cheaply enough, and the public's fear of "Nukular powered cars OMG we're all doomed!" overcome, it would finally provide a working alternative to fossil fuel for powering cars. But at "125-micro-Watts per cubic centimeter", we're not *quite* there yet. I think you'd still need to increase the power density by about 1000 times to make a workable vehicle power source.

Gullible Jones
2005-Dec-16, 09:07 PM
What if you used an alpha emitter? That might require some reengineering to compensate for higher-energy, less penetrating particles, but the energy output might be significantly greater.

HenrikOlsen
2005-Dec-17, 04:09 AM
The effect used is specifically about an electron crossing a p-n junction, so it's strictly limited to beta decay.

Gullible Jones
2005-Dec-17, 04:57 AM
You couldn't do the same with n-p junctions on a much smaller scale, and alpha particles?