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The idea of this making it into any consumer product is science fiction, and articles like this can be safely ignored. Some back of the envelope math to illust

The idea of this making it into any consumer product is science fiction, and articles like this can be safely ignored. Some back of the envelope math to illustrate why: - The decay energy of Ni-63 is 66 keV, but since the energy is split with an irrecoverable neutrino, the average recoverable energy per decay is more like 17 keV. - The typical power consumption of an iPhone is about 10 watts, give or take. - Converting (1eV = 1.6e-19 J, 1W = 1J/s), we get 2.72e-15 Watts per decay. - Assuming 10 Watts for your phone, we get 3.68e15 decays/second, 3.68e15 Bq, or *99364 CURIES* of activity - The US NRC exempt quantity for Ni-63 is currently 1e-5 Curies (10 micro-Curies) (10CFR30.71, Sched. B) For reference, the activity of the Am-241 in a typical smoke detector is on the order of 0.1 MICRO Curies. A betavoltaic battery for a smartphone would need a full 20 orders of more activity per unit, 18 orders of magnitude higher than the current regulatory limits, and we're talking about a product that nearly every person in the country owns. The item would be physically warm to the touch, could never be turned off, and would need piles of paperwork to track the origin, transfer of custody, and proper disposal. Maybe this makes sense for remotely-deployed military equipment and other niche applications where the user would go thorough the necessary licensing steps, but for consumer products, forget it. Absolute fiction.

EA-3167 3y ago
The fact is that beta batteries have been around since the 1960's, and for the reasons you've described they're not really useful for commercialization. I'd add that even if they were somehow absolutely foolproof, you'd still need strict regulatory oversight of disposal/recycling. The cost would be immense, the benefits would be slim at best.
m-p-3 3y ago
I wouldn't mind having a dumb watch with one of these batteries that would basically never need to be replaced throughout its lifetime. That would be a cool exercise to make it comsume the tiniest amount of power as possible.
- rkangel 3y ago
  My (Citizen) watch is solar powered which achieves the same effect without the nuclear complexities. Not as cool obviously!
jauntywundrkind 3y ago
Your numbers are ahem a bit off. An iPhone 15 has a 3367 mAh battery. Around 12 watts. It lasts longer than 1 hours 12m. Probably even running full tilt. I think your post indicates a narrow "can this power the whole phone" thinking that is over-applied when considering this power source. The power here is faint, but the energy is vast, & we should assess that merit too. The previous post called this is a 100mW battery. That's not enough power for active use for a phone, but it's probably enough to idle a phone ok, and if designed well leave some extra capacity for very slow charging a conventional battery, depending on the phone. That might be enough for some light phone use and being net neutral on any given day! It might be enough to run some flip phones during calls, possibly. Anyways, you've over hyped the requirements by 100x what's on offer here. I think even 2 or 3x what's available here is probably enough to make a phone than many people might never have to recharge, if supplemented by a higher power store (conventional chemical cell) to bank some of the output energy. The idea still sounds risky & scary to me, but I at least want us to be looking at vaguely the right order of magnitudes when we assess.
- fastneutron 3y ago
  Whether it's 1 Watt, 1000 Watts or 0.0001 Watts is utterly irrelevant. It's the activity that matters. Even at the power quoted in the article of 100 microwatts, you're still talking activities on the order of a full Curie, assuming 100% efficiency (betavoltaics are down in the 10s and 20s, realistically). Curie-quantities of activity in a package the size of coin is real activity, not the nanobananas of tritium in the pacific the media likes to segfault over. No nuclear regulator in their right mind, in any country on Earth, would generally license, let alone exempt, a Curie-level quantity of any isotope for widespread consumer usage. The title of the article was "A tiny radioactive battery could keep your future phone running for 50 years." I can assure you this will not be going in anybody's personal electronics. At best, it will power some board-level electronics operating in the Arctic or at the bottom of the ocean, maybe a cubesat or keep-alive circuit on a space probe. Militaries, government agencies and companies with the motivation and resources to deal with the licensing could definitely have a use case here. Your average Joe will remain stuck with smoke detectors, tritium keychains, polonium static brushes, and uranium rocks as the hottest isotopes they can (legally) get their hands on.

EA-3167 3y ago

The fact is that beta batteries have been around since the 1960's, and for the reasons you've described they're not really useful for commercialization. I'd add that even if they were somehow absolutely foolproof, you'd still need strict regulatory oversight of disposal/recycling. The cost would be immense, the benefits would be slim at best.

m-p-3 3y ago

I wouldn't mind having a dumb watch with one of these batteries that would basically never need to be replaced throughout its lifetime. That would be a cool exercise to make it comsume the tiniest amount of power as possible.

rkangel 3y ago
My (Citizen) watch is solar powered which achieves the same effect without the nuclear complexities. Not as cool obviously!

jauntywundrkind 3y ago

Your numbers are ahem a bit off. An iPhone 15 has a 3367 mAh battery. Around 12 watts. It lasts longer than 1 hours 12m. Probably even running full tilt. I think your post indicates a narrow "can this power the whole phone" thinking that is over-applied when considering this power source. The power here is faint, but the energy is vast, & we should assess that merit too. The previous post called this is a 100mW battery. That's not enough power for active use for a phone, but it's probably enough to idle a phone ok, and if designed well leave some extra capacity for very slow charging a conventional battery, depending on the phone. That might be enough for some light phone use and being net neutral on any given day! It might be enough to run some flip phones during calls, possibly. Anyways, you've over hyped the requirements by 100x what's on offer here. I think even 2 or 3x what's available here is probably enough to make a phone than many people might never have to recharge, if supplemented by a higher power store (conventional chemical cell) to bank some of the output energy. The idea still sounds risky & scary to me, but I at least want us to be looking at vaguely the right order of magnitudes when we assess.

fastneutron 3y ago
Whether it's 1 Watt, 1000 Watts or 0.0001 Watts is utterly irrelevant. It's the activity that matters. Even at the power quoted in the article of 100 microwatts, you're still talking activities on the order of a full Curie, assuming 100% efficiency (betavoltaics are down in the 10s and 20s, realistically). Curie-quantities of activity in a package the size of coin is real activity, not the nanobananas of tritium in the pacific the media likes to segfault over. No nuclear regulator in their right mind, in any country on Earth, would generally license, let alone exempt, a Curie-level quantity of any isotope for widespread consumer usage. The title of the article was "A tiny radioactive battery could keep your future phone running for 50 years." I can assure you this will not be going in anybody's personal electronics. At best, it will power some board-level electronics operating in the Arctic or at the bottom of the ocean, maybe a cubesat or keep-alive circuit on a space probe. Militaries, government agencies and companies with the motivation and resources to deal with the licensing could definitely have a use case here. Your average Joe will remain stuck with smoke detectors, tritium keychains, polonium static brushes, and uranium rocks as the hottest isotopes they can (legally) get their hands on.