A betavoltaic device uses beta particles from radioactive decay to generate electricity. Basically, it works like a solar cell, but using radiation instead of light.
Hypothetically, this could be used to make batteries which last a long time. Using thin layers of radioactive carbon-14 sandwiched between layers of semiconductive diamond (which would also keep the radioactivity contained), tiny batteries like these could supply small amounts of power for thousands of years. Prototypes have been made using nickel-63 as the energy source,
@FuchsiaShock For real, imagine having a phone or something which you never need to charge. Just swap the battery out once every couple of decades and you're good!
@InvaderXan @FuchsiaShock i looked into this too a while back! the trouble is that betavoltaic cells have power output typically in the range of tens to hundreds of microwatts, which can be useful for low draw hard-to-reach applications, but many orders of magnitude lower than what a phone battery puts out (on the order of 1-10W). for that you'd need something more like a SNAP RTG, using the decay heat from a slug of plutonium to drive thermocouples. smaller slug in this case and thus cooler running, since it just needs a few watts and not the hundreds that space rated RTGs produce, but i don't know any other passive nuclear process that has power density comparable with lithium batteries. (and plutonium is also pretty hazardous, less for its alpha emissions than because it's a toxic heavy metal and also occasionally pyrophoric. idk how i'd feel about carrying that around in my pocket, however well shielded)
(also as someone who literally has an "atomkraft? ja, bitte!" sticker on her laptop i feel bound to note that we could probably most easily produce beta sources at industrial scale via neutron activation in a running reactor, the same way a lot of medical isotopes are made)
@InvaderXan Don't tell this to Musk. He'll mine all the radioactive carbon in the name of saving the planet.
@vicorva @InvaderXan it's actually new iteration of quite old and commonly used technology. Most of our deep space probes are powered by RTG devices https://en.m.wikipedia.org/wiki/Radioisotope_thermoelectric_generator that is devices that use heat gradient between radionuclide and environment to produce electricity. I think Martian rover will also use that.
Soviet Union used RTG to power siberian lighthouses (before GPS). I think they had other wacky ideas for it but overally safety was a concern.
@Jo Low energy beta radiation is easy to contain. The concept here is to use layers of diamond which are thick enough to contain the radioactivity while also acting as semiconductors to generate electric current.
In short, if it’s properly constructed, it should be perfectly safe.
@Jo Side note: for a while, in the 20th century, people made wrist watches which used radioactive paint to make the numbers glow in the dark. Pretty clever idea, really. The watches themselves weren’t dangerous at all to the people wearing them, as radiation couldn’t escape from the glass and metal of the watch casing. The danger was to the factory workers who were assembling them, using radioactive paint for hours every day, which had the kind of effect you might expect.
But in a world where robots can do these jobs, that shouldn’t be a problem.
@InvaderXan @Jo Yeah, to minimize the risk of rupture, batteries should definitely be resistant to impact, tampering, and corrosion, as well as firesafe, given the flammability of diamonds. At smaller sizes, it's generally okay, but if these end up being used similarly to classic RTGs for longterm systems, the casing should be up to the task to avoid any INES events at large scales.
@bunny_jane @Sapphicgiraffic @Jo I’m still excited for the sugar batteries. I hope they turn out to be viable, because they’d certainly be environmentally friendly. https://solarpunk-aesthetic.tumblr.com/post/175493229780/sugar-batteries-one-big-challenge-in-renewable
@InvaderXan I think my favourite part is that in the '70s, a few people actually had pacemakers fitted that ran off betavoltaic cells.
It sounds like such a science-fictional concept, but there used to be cyborgs walking around whose hearts beat to the rhythm of a nuclear-powered implant.
(Nowadays, they're powered by lithium batteries instead, which somehow doesn't sound as cool).
@lilly Ooo yes, I read about this! Honestly, you’re so right, the idea of someone whose heart is powered by radiation from decaying atoms is just seriously cool!
Hay un start up muy propagandeado con esa idea. El problema es que no hay ningún avance respecto de lo que ya se sabe desde hace décadas, sólo hay confianza en que "nosotros lo lograremos". Como Elon con el neuralink o el hyperloop, son pibes que ser creen destinados a ser más vivos que la gente que se atascó en esos problemas antes.
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