Antonio, check out this web site:
http://www.rexresearch.com/nucell/nucell.htm It's about possible strontium batteries. I don't think the ideas work, yet, but the theorizing is interesting, about converting strontium radiations, directly into electricity. I think it's worth the read, just for the extra-ideas of theory...
May have something to do with our quests for cold/hot fusion, etc....
Oh, and BTW, in my searchs, I've come across information of black-hole theory, that electrons are stripped from protons/neutrons, inside black-holes, thus allowing high mass compaction, and possible fusion...? Let me know your ideas about mass/fusion in black-holes, if you would...?
Lloyd