Talk:PowerPedia:BetaVoltaic

From PESWiki

I have been unable to get confirmation of their claims. See my page on these people at

http://www.phact.org/e/z/betavolt.htm

Comment by another reader: The article makes some simplifications that make some statements sound incomplete. For example, in more than one instance the author says that a neutron disintegrates into proton leaving it to the reader to recognize that a beta particle is also produced. A more accurate statement would be that a neuton disintegrates into a proton, an electron, an anti-electron neutrino, plus kinetic energy shared by all three particles.

The energy of the beta particle (fast electron) is generally measured in keV or MeV, but the nuclear battery does not produce an output measured in kilovolts. Much of the energy transferred to the semiconductor appears only as heat.

Some other statements are more incorrect. The author states that nuclear batteries are not radioactive when the cells are spent. Tritium has a half-life of 12.33 yrs. After about two half-lives, the cell is considered spent because its radioactivity has fallen to 1/4 of it's original value, the semiconductor material has also suffered damage, so cell output has fallen to less than 1/4 of original. It is still radioactive; however.

The author states that K-40, Mo-100, and Zn-70 are promising beta sources that are not regulated by the government because of their very long half-life. This is inaccurate.

K-40 is not regulated by the US NRC because it is a naturally occurring radioactive material (NORM), amounting to about 0.0119% of natural potassium. K-40 is regulated by most state radiation control agencies when it is purified to a concentration above 0.002 microcuries per gram. Pure K-40 activity calculates to ~7.15-uCi/g.

Mo-100 and Zn-70 are naturally occurring non-radioactive isotopes of these elements. Since they emit no observable radiations, they are <0.002-microcuries/g and are not regulated as radioactive materials.

The paper needs rewritten, but I would need to research further to do a complete job of editing. Other types of nuclear batteries exist which are not discussed in the article. I'll leave the rewrite to the original author or others.