3

A 2012 pre-print, Self-Charged Graphene Battery Harvests Electricity from Thermal Energy of the Environment claims that a graphene device was used to generate a voltage of 0.35V by capturing some of the energy of ionic thermal motion in a solution of CuCl2.

They claim to have excluded the possibility that this voltage was driven by a regular chemical reaction.

This result has been widely positively cited on the web. However, it also had its detractors:

Nature had a blog article, Sparks fly over graphene energy device:

Few researchers are convinced.

It cites a few researchers pooh-poohing the result.

I haven't heard of any further developments regarding it.

Was a prototype device built that showed that power could be drawn from ionic thermal motion?

Oddthinking
  • 140,378
  • 46
  • 548
  • 638
RLR
  • 177
  • 1
  • 6
  • 2
    Why this random preprint and not any of the better articles in the field (like https://doi.org/10.1038/s41467-019-12144-2 for example)? – CJR Oct 27 '21 at 04:03
  • 1
    @CJR: Is that an answer? – Oddthinking Oct 27 '21 at 06:05
  • 1
    @CJR That article has no authors in common with OP's preprint, and it seems to be about an ordinary heat engine. OP's preprint and blog post are about a device that seems to violate the laws of thermodynamics. – benrg Oct 27 '21 at 07:51
  • 1
    @benrg There's no violation of the laws of thermodynamics - extracting thermal energy from a system decreases the temperature of the system, and there's no claim otherwise. I know that there's a lot of thermal battery research going on, so I was curious why the question is about a decade-old preprint and not more recent work in the same field that uses different methods. – CJR Oct 27 '21 at 11:18
  • @CJR You should continue reading past the first, and check out the implications of the *second* law of thermodynamics. – user253751 Oct 27 '21 at 14:02
  • 3
    I don't think that there's a clear violation of the second law either - there's an increase in entropy associated with changes to the physical components of the system (this probably sets the lifespan of the whole device). I think it's probably garbage science and doesn't actually work (seems like it would have been replicated and not left to rot on arxiv if it worked), but there's a lot of bad science out there. You could ask this question about any of 20,000 preprints or low-tier junk journal articles. – CJR Oct 27 '21 at 14:29
  • 1
    Google Scholar offers [3 citations of the 2012 arXiv paper](https://scholar.google.com/scholar?cites=3513272718914271727&as_sdt=2005&sciodt=0,5&hl=en) one of which looks possibly relevant but behind a paywall, one of which is irrelevant and the third goes to an indexing site in Russian. So this does not seems to have led to substantial follow-up research – Henry Oct 27 '21 at 16:33
  • 2
    @CJR: worth noting that the 2019 paper only achieves 0.1V at 25C (and 0.24V at 70C). So the claims in the 2012 paper were probably outlandish. Frankly graphene has a lot more potential in sodium-ion batteries https://pubs.acs.org/doi/10.1021/acsmaterialslett.1c00280 – Fizz Oct 28 '21 at 13:24
  • 3
    I fully expect this comment to be delete as O/T, but for anyone interested in the latter; here's an open access paper https://www.science.org/doi/10.1126/sciadv.abf0812 – Fizz Oct 28 '21 at 13:35
  • Related https://physics.stackexchange.com/questions/583587/is-thibado-s-graphene-brownian-capacitor-charger-perpetual-motion-of-the-second – Fizz Oct 29 '21 at 01:18
  • 2
    It should be noted that there's a big difference between generating a potential difference (voltage) and generating usable power. When you rub a balloon on your sweater you build up a static charge of thousands of volts, but the actual energy in that charge is minute and basically harmless. – GordonM Oct 29 '21 at 08:31
  • 3
    @GordonM: You mean I can't power my electric car by dragging a bunch of balloons behind it? There goes my plan! – Jörg W Mittag Oct 31 '21 at 21:18
  • 1
    @JörgWMittag Wouldn't work, anyway. The road isn't made of sweater. – user253751 Nov 02 '21 at 10:29
  • CuCl solution and silver/gold electrodes... how they think they excluded chemical shenanigans is beyond me – bukwyrm Nov 04 '21 at 23:07

0 Answers0