Sciencemadness Discussion Board

Nuclear Batteries

FrankRizzo - 29-9-2004 at 17:00

Here's some interesting reading regarding the possible future of nuclear batteries.

http://www.spectrum.ieee.org/WEBONLY/publicfeature/sep04/090...

Oxydro - 29-9-2004 at 17:57

I always kind of wondered why you couldn't just make a nuclear power cell just like this:
http://oxydro.atspace.com/nukecell.htm
Sorry I couldn't just post it, but atspace doesn't allow hotlinking so I have to route you through the page... I can't remember my logins for my other accounts (that maybe support it).

Anyway, the idea is that alpha particles radiate from a source, and encounter a wall, picking up two electrons to form helium, and leaving the wall with a positive change. In version 2, there is also a beta source producing a corresponding negative charge.

I'm fairly sure that there's a very obvious and simple reason that they don't work, but II just can't happen to think of it at the moment.

Marvin - 1-10-2004 at 00:14

FrankRizzo,

For what its worth I think the whole article is a pipe dream. What with speculation about dirty bombs noone is willing to put nuclear batteries with any significant amount of power in the hands of ordinary people.

Oxydro,

That does work, eg Strutts radium clock. Where the voltage produced charges a gold leaf electroscope which then shorts. Not entirly unlike the piezoelectric generator described in the article though a century or so earlier.

The thing is though, you dont want a 6 million volt battery at a few picoamps. You also have the problem that as the helium is produced it gets more difficult to keep the thing insulated. If its not done in a vacuum you generate ionisation that shorts out the power produced.

Reverend Necroticus Rex - 1-10-2004 at 19:48

I gave much thought of late to nuclear batteries, how about utilizing the heat produced by decay, some deep-space probes use batteries like this powered by curium i believe.

One allotrope of boron monosulfide is apparently the strongest thermoelectric substance known to science, not sure what allotrope though, how about a very simple arrangement of a shielded casing, with layers of the monosulfide, and a long-lived radioisotope, with a couple of wires.

Simple enough arrangement, and all the heat produced by decay would be transmuted into energy, simply hook up the battery to the desired applience and go:)

FrankRizzo - 1-10-2004 at 20:41

Rev,

Actually, the report that I linked to talks about that very idea. Apparently, the effect doesn't scale down very efficiently. Due to the low cross section of wire that would be exposed to the heat versus its surface area, the amount lost to radiance is too high to maintain the temperature.

[Edited on 2-10-2004 by FrankRizzo]

JohnWW - 2-10-2004 at 01:42

Quote:
(cut) One allotrope of boron monosulfide is apparently the strongest thermoelectric substance known to science, not sure what allotrope though, how about a very simple arrangement of a shielded casing, with layers of the monosulfide, and a long-lived radioisotope, with a couple of wires. (cut)

Boron monosulfide? BS? I know what that stands for!

Seriously, though, the heat from long-lived radioactive isotopes can be used to power thermopiles, consisting of several junctions of dissimilar metals, "thermocouples". Plutonium-powered thermopiles are used in this way in NASA spacecraft that venture too far from the Sun or solar cells to be used, e.g. the Voyager and Pioneer spacecraft which were sent to the remotest parts of the solar system.

John W.

[Edited on 2-10-2004 by JohnWW]