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Recently, for some reason, this story first published in January 2020 was again trending on social media (this appeared on my YouTube feed)But for a more quotable version, this version from The Independent) appeared in January:

NUCLEAR WASTE RECYCLED INTO DIAMOND BATTERIES WITH 'NEAR-INFINITE POWER'

One scientist from Bristol University who was involved with the project claimed in the article that:

"Eventually, a highly powerful version of a diamond battery could power a mobile phone," James Barker, from the University of Bristol's Faculty of Engineering, told The Independent.

The company website goes further, claiming that its technology will revolutionize batteries:

NDB can be used to further the electric vehicle revolution...

With NDB, every device you own, be it a smartphone or a laptop, can contain a miniature power generator, thus negating the need for constant charging...

And many other related claims.

The technology behind the claims involves capturing the energy released by the radioactive decay of carbon-14 derived from nuclear waste and turning it into electricity. So, strictly speaking, they are not "batteries" but an alternative source of power than is claimed to be able to replace batteries.

Are these claims remotely physically credible or total nonsense given the technology behind the batteries? For example, the firm claims they could power a mobile phone indefinitely: is that possible?

matt_black
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    BTW it occurs to me that this might be better on Physics.se as the refutation might warrant back of an envelope calculations which are often disapproved of here. Happy to go with the community judgement. – matt_black Sep 01 '20 at 20:03
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    @Oddthinking I went with a generic claim in the title and a specific claim from the website in the body. Is that OK? – matt_black Sep 01 '20 at 21:59
  • Did you get a chance to check the link I posted before it was deleted? These batteries have been around for 100 years. – Daniel R Hicks Sep 01 '20 at 22:01
  • @DanielRHicks I've seen the links before and you are right. But I thought the question worth posting given the renewed attention for the outrageous marketing claims the firm is making while trying to raise money. The links would be good in an answer. – matt_black Sep 01 '20 at 22:04
  • I can't post an answer at the moment, but this [debunking video](https://lbry.tv/@eevblog:7/eevblog-1333-nano-diamond-self-charging) may provide a starting point for anyone else who wants to write one. – sempaiscuba Sep 02 '20 at 00:48
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    Something you learn after watching battery-technology advances for a while: two or three times a year, someone comes up with a breakthrough that will revolutionize the battery industry. In the thirty years or so I've been watching, only two of those breakthroughs actually made it to market. – Mark Sep 02 '20 at 02:46
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    @matt_black: It is much better, but still vague. I read a battery expert complaining that a good rechargeable battery needed to have about ten qualities (high density, fast recharging, efficient, ability to hold charge, number of lifecycles, not being likely to explode, cheap, etc.) and there would often be big announcements because someone came up with a new technology that did very well in *one* of those qualities while being so terrible at the others it was unmarketable. Is that a "breakthrough"? Yes and no. – Oddthinking Sep 02 '20 at 08:57
  • I saw extra info about those batteries on an article on Wired as well (https://www.wired.com/story/are-radioactive-diamond-batteries-a-cure-for-nuclear-waste/), which appears a lot more reasonable with its claims and points out massive limitations. I would hazard a guess that they do exist, but are so painfully inefficient that it limits those to extremely niche applications. – Entropy Sep 02 '20 at 10:05
  • @Oddthinking I added a paragraph explaining the underlying technology. It is very specific and not like many of the generic claims of "improvements" in normal battery tech. This should clarify why skepticism about the claims is warranted. – matt_black Sep 02 '20 at 10:11
  • @DevSolar The key issue for me isn't the *source* of carbon-14: it is whether the technology can achieve what they claim it can. This is also, I think, easy to refute from anyone with a grasp of the basic physics of radioactive decay. I actually suspect that the processing of nuclear waste is not the primary problem here. – matt_black Sep 02 '20 at 10:56
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    From what I can tell, they aren't a battery, strictly speaking. They are instead a current source, with the electrons produced by the beta decay of carbon 14 atoms provides the source of the current. (The heat produced by the beta decay is not used.) I get 26.57 microamps per kilogram of carbon 14 assuming 100% efficiency. – David Hammen Sep 02 '20 at 12:52
  • @DavidHammen You are quite right about how they work. And that calculation is similar to mine which suggests they won't have any impact on the phone industry as phones need amps not milliamps of power at peak load. – matt_black Sep 02 '20 at 12:56
  • @matt_black - I wrote 26.57 microamps, not milliamps. A metric ton would be needed to yield 26.57 milliamps. That might be enough to power a cellphone in airplane mode with WiFi and bluetooth disabled. – David Hammen Sep 02 '20 at 13:11
  • @DavidHammen Consider that a typo. You are quite right. My calculations came closer to several hundred kg but that's close enough for a refutation! – matt_black Sep 02 '20 at 13:14
  • @matt_black As you noted, back of the envelope calculations are typically rejected as answers at this site. I can give references for each of the numbers I used: The molar mass of carbon 14, the number of atoms per mole, the carbon 14 half life, what half life means, and the electric charge. – David Hammen Sep 02 '20 at 13:25
  • @DavidHammen I think that facts requiring basic high school or wikipedia science should be OK here, but the moderators often disagree. Worth a shot, though, since there is nothing controversial in the calculations. – matt_black Sep 02 '20 at 13:27
  • As mentioned by Daniel the technology has been known for a century, but there have been some developments as described in a recent story in [Mining.com](https://www.mining.com/nano-diamond-battery-that-lasts-for-28000-years-closer-to-becoming-commercial-product/). A breakthrough is presumably what the company linked is *hoping* for. Their website has nothing definite, no products, but plenty of optimism. – Weather Vane Sep 02 '20 at 13:37
  • @DavidHammen So all you have to do is make the physics somehow work 1 million times better and then you can power a car with it, right? – user253751 Sep 02 '20 at 14:28
  • What an incredible scam. (They should pay a few dollars to have someone correct all the broken English on the web site.) – Fattie Sep 02 '20 at 17:02
  • infinite in the sense that if i give you a penny a year one day you'll be a millionaire. – dandavis Sep 03 '20 at 04:16
  • Technically speaking, a standard D-size flashlight "battery" is not a battery but rather a "cell". A "battery" is an array of canons ... or electrical cells. Anything that that isn't an array and that produces voltage/current (you can't have one without the other) is a "cell". – Daniel R Hicks Sep 04 '20 at 11:56
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    @DanielRHicks Etymologically, you are correct; but in anything but the most specialist contexts, the word "battery" is used regardless of whether the internal structure consists of multiple "cells". I actually have no idea whether the batteries I use are a single cell or multiple, and it makes no difference to my use of them, so the distinction would serve no purpose. – IMSoP Sep 04 '20 at 13:23

1 Answers1

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Already from the draft article appearing on Wikipedia you can spot the issue:

Its power density will be far lower than that of conventional chemical batteries

If they get to the market as they are now their applications would be restricted to a few cases filling small niches. The quote you added in your question:

Eventually, a highly powerful version of a diamond battery could power a mobile phone

highligts that current prototypes aren't even enough for a mobile phone. Regarding the claimed applications I see on their site:

Automotive

Even if the battery worked as a generator recharging the chemical batteries while the vehicle is parked, with such power density, their contribution would be negligible. Even increasing the power density by an order of magnitudes would not be enough.

Aerospace

Here they are nothing new. They have to compete with Radioisotope thermoelectric generators

Consumer electronics

Such battery would provide a small current continuous over time, it would have to be coupled with a chemical battery for the moments you talk or play a video. Will future mobile phones have room for two batteries?

Medical Technology / Industrial /Defense

Maybe, but we are talking about some niche applications, not a wide scale revolution

Another questionable claim is that they would be good to recycle nuclear waste, but nuclear waste contain a big number of different isotopes how many of them would be suitable? According to the article you linked until now they are planning to use Carbon 14.

Furthermore some isotopes are already used in Radioisotope thermoelectric generators, but not all the available material is exploited because the cost to refine the nuclear waste hardly repays the energy provided unless a special energy source is needed.

FluidCode
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  • The first wikipedia quote is vague. An actual calculation of the power density would be far clearer. Are we talking a factor of 2, 10 or a million? – matt_black Sep 04 '20 at 12:09
  • @matt_black I don't know whether they actually released a detailed information about power density. In this article they talk about it, but still with vague comments: https://techxplore.com/news/2020-08-energy-firm-nuclear-waste-fueled-diamond.html – FluidCode Sep 04 '20 at 12:20
  • @matt_black The only released numbers I found are from a previous experiment: https://www.sciencedirect.com/science/article/abs/pii/S0925963517307495 – FluidCode Sep 04 '20 at 12:22
  • There is a good reason they didn't talk power density. Simple calculations of the power density of carbon 14 from its known radioactive properties would show their product claims to be extremely bogus. – matt_black Sep 04 '20 at 12:22
  • @matt_black other isotopes have higher power density, e.g. NIckel 63 tested by others, but generators of these types usually have small efficiency – FluidCode Sep 04 '20 at 12:25
  • What mass of nickel 63 or carbon 14 would be needed for normal battery-level power density? (even assuming perfect conversion) – matt_black Sep 04 '20 at 12:30
  • According to [their collaborators](https://www.bristol.ac.uk/media-library/sites/cabot-institute-2018/documents/Diamond_battery_FAQs_Nov_2016.pdf) 1g of C14 produces about 15J per day. A mobile phone needs ~30,000 J/day . I think they are underestimating that but the number comes from an optimistic press release. – matt_black Sep 04 '20 at 21:57
  • @matt_black So you'd need over 4 pounds of C14 to generate enough Jules to power a mobile phone? – GrumpyCrouton Oct 05 '20 at 14:14
  • @GrumpyCrouton If those calculations are right, yes. Others get numbers of 10s to 100s of Kg. – matt_black Oct 05 '20 at 15:11