Hope for battery cars?

Discussion in 'General' started by Martin Williams, Mar 16, 2018.

  1. Martin Williams

    Martin Williams Active Member

    Well, not quite batteries, but supercapacitors.

    http://www.bris.ac.uk/news/2018/february/supercapacitor.html

    Those stupid enough to be taken in by the Estor scam will think "We've been here before!" but these devices seem to be a trifle more plausible. They have at least demonstrated them actually working and they seem to be one or two orders of magnitude better than existing double layer capacitors.

    One really nice feature of capacitors as energy stores is that they provide a very simple and accurate way of knowing how much energy you have left. It is proportional to the square of the voltage. All you need is a voltmeter, suitably calibrated.

    In terms of energy density, they seem to be comparable with Lithium batteries, but how they tolerate high and low temperatures, vibration, and other conditions experienced in cars is as yet unknown, as is cost. And safety is a further potential showstopper, so I'll believe it when I see it.

    I don't know what it will mean to Mr Musk's enormous battery factory though. Perhaps he can easily turn it over to an enormous supercapacitor factory very easily.

    We shall see.
     
  2. Martin Williams

    Martin Williams Active Member

  3. Domenick

    Domenick Administrator Staff Member

    Looks promising. However, 180 Wh/kg is about where Tesla/Panasonic was 10 years ago, and since this supercapacitor is still years from being commercialized, it's not likely to be used in cars. 300 Wh/kg would be a more compelling energy density right now, but it's a moving target.

    Still, it's definitely an astounding sounding breakthrough and will be useful in any number of applications.
     
  4. Martin Williams

    Martin Williams Active Member

    I don't think Tesla were there 10 yers ago. The Model 3 battery pack is currently claiming 150Wh/kg.

    I think the difference is in claims for one cell and the complete pack. The cooling needed for the batteries reduces the overall energy density.

    In a capacitor back I would expect to get away with NO cooling as the only losses are resistive ones in the interconnections. These are negligible in comparison to battery losses.
     
  5. Martin Williams

    Martin Williams Active Member

    Some information on their performance in this abstract from a paper produced by a Chinese team. It looks good to me

    http://pubs.rsc.org/en/Content/ArticleLanding/2016/TA/C6TA00643D#!divAbstract

    No mention of how they are affected by temperature though, and that's just one thing that could scupper it. I think it is encouraging that others are now working on these things though. I expect progress will be rapid as the competition to develop them to commercial level heats up. I'd love one in my phone!
     
  6. Pushmi-Pullyu

    Pushmi-Pullyu Well-Known Member

    To re-post my recent comment on this subject from another thread:

    That was what got so many people (including myself) excited about EEStor's claims; the claims that they were gonna make supercapacitors with the energy density of li-ion batteries. On paper, supercapacitors are so much better than batteries for storing electrical power! They charge and discharge instantly, without significant heat loss; they don't use chemical reactions to store power, so are pretty immune to temperature changes; and they can be put thru charge/discharge cycles tens of thousands of times without significant loss of capacity.

    Yeah, on paper they look great! Sadly, in practical terms, the energy density is hopelessly low, and they don't retain stored power for days, or even for many hours. EEStor's claims turned out to be utterly and completely false. We can realistically hope that with use of graphene or carbon nanotubes, the surface area might be increased to the point that the energy density of future supercapacitors will be competitive with li-ion batteries. But the "leakage" of the power, just from sitting on the shelf for a few hours... that might prove a far harder problem to solve.

    * * * * *

    This new claim for breakthrough supercapacitors is described as having about two orders of magnitude improvement for energy density over existing supercapacitors. Yeah, this does seem highly reminiscent of EEStor's claims.

    On the hopeful side: This tech appears to have multiple people involved with the development; it's not a one-man operation like Dick Weir and EEStor's "EESU", for which the claims ultimately proved to have no foundation at all.

    On the doubtful side: One thing that always kept me somewhat skeptical of EEStor's claims is that they never were willing to do a public demo of their tech. That was a significant red flag for me from the start, a red flag which only grew bigger as time went along.

    So one troubling thing I see in the press release that Martin linked to is the statement "...and they are ready to demonstrate their results." This despite various claims further down in the press release; for example, that the supercapacitors have been used to "run demonstration devices". If the so-called "demonstrations" have only been what the team claims to have demonstrated internally in lab tests, without any public demonstration, then we're right back at yet another claim for a "magic supercapacitor" tech which has not been publicly demonstrated, just like EEStor.

    So while the press release here reads like a very strong claim for a truly revolutionary breakthrough, I'm going to maintain a healthy scientific skepticism, just as I did with EEStor's claims. And I will continue to do so until the devices have been tested by a technically qualified, truly independent third party laboratory or team. That's what the more hard-headed skeptical members of the (now defunct) TheEEStory forum persistantly demanded from EEStor, and when we finally got that, after several years of claims without actual proof, those tests showed pretty clearly that none of EEStor's extraordinary claims were true.

    Nope. Tesla's Gigafactory One is set up with a large-scale Panasonic factory inside to make lithium ion battery cells. Altering the chemistry to make a different type of cell might not be too big a disruption, and possibly not all that expensive as compared to the total cost of constructing Gigafactory One.

    But supercapacitors are a very different ball game, and so far as I know, Panasonic has no expertise in making those. It seems to me that if Tesla were to switch to using supercapacitors rather than batteries for powering their cars, then they would have to find a new partner for building the "battery" packs. While I am confident in Tesla's expertise in being able to adapt to the new technology -- Tesla is still a young and small enough company to react much quicker to tech breakthroughs than are larger "legacy" auto makers -- at the same time, let's be realistic: The change from batteries to supercapacitors would take years and cost billions, even for Tesla. It would also cause Tesla's stock price to take a severe beating, because with the massive investment in Gigafactory One, Tesla has "bet" quite a lot -- in terms of capital investment and tangible assets -- on current battery tech. With a sharp drop in stock price, Tesla would suddenly find it much harder to borrow more money on advantageous terms; money it would need, to the tune of billions of dollars, to pay for the switch from powering their cars with battery packs to powering them with capacitor packs.

    Would this be enough to drive Tesla into financial ruin? I'm not a "financial guy", so I don't think I have an informed opinion on that. But I'm pretty sure that, coupled with Tesla's increasingly deep debt, it would at least put the company on financially shaky ground.

    However, on the plus side, I think Dominick has an excellent point: Even if this "magic supercapactitor" tech does prove to be commercially viable -- and as noted above, I think that's a big "if" -- it will almost certainly take some years before it is mass produced at a price which will make it competitive with li-ion batteries. Given several years to adapt, it seems reasonable to believe that Tesla can come out the other side, and with a better "battery", stronger than ever in terms of Tesla's cars competing with gasmobiles. Keep in mind that if Tesla is caught flat-footed by a revolutionary new electrical energy storage tech, then every other EV maker will be, too. So a breakthru tech like the one described here wouldn't put Tesla behind in the race, altho we can bet money that the dedicated Tesla bashers and short-sellers would rush like a horde of lemmings to claim precisely that! :p :cool:
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    Last edited: Mar 20, 2018
  7. Martin Williams

    Martin Williams Active Member

    Estor's claims were clear nonsense from day one. They weren't even 'super' capacitors, they were ordinary capacitors pushed to ludicrously high voltages - far higher than any dielectric could have tolerated. I don't think anything was demonstrated, just promises of future glorious success. What got people excited was their own gullibility and in many cases stupidity, and a refusal to listen to look at the problems.

    I think the differences this time are that demonstration capacitors with high energy density have actually been produced. The Japanese group seems to have pushed the energy density up a notch by combining the new dielectric material with high surface area plates. No doubt this will be improved upon as more groups start making and experimenting with these things. Problems remain with considerations like scalability, reliability, and performance over a wide temperature range plus, probably, a few unanticipated problems, so it's far from a done deal, but initial indications are encouraging.

    In practical terms I think there are problems in charging these things - in cars- as fast as claimed. There are problems in getting the large amounts of energy needed to run a car into a capacitor quickly, which will no doubt become apparent when someone tries to do it. As far as Tesla's enormous battery factory is concerned, I would think it possible to change from battery to supercapacitor production fairly easily, but it will be expensive, as I imagine the licence to do so will be. No doubt Musk will be able to persuade his investors to cough up though. Who knows, maybe Ford or Nissan will offer more for the IP rights too.

    It is worth noting, too, that supercapacitors are different from batteries. As batteries discharge the output voltage from them stays constant until they are fully discharged. Capacitors (super or otherwise) do NOT. The output voltage falls proportional to the charge taken from them, so I would imagine a considerable redesign of the electronics between the battery pack and the motor will be needed too. Not difficult in theory, but I don't know how big an impact this would have on the car or the motor.

    How long will they take to produce commercially? Hard to say. Nobody is going to worry about production methods until the science is sorted out, but they seem to be able to make them already in form very similar to the construction of existing supercapacitors - a bendable flat film or tape that can be wound into a roll that fits into a cylindrical battery - so perhaps someone like Maxwell will be able to produce them with existing production equipment very quickly indeed with energy densities much higher than their current products.

    I think one of the possible effects if this technology becomes widely known about, would be to make people considering a battery car to hold off buying one. If capacitor cars are perceived as the coming thing, who would invest money in a technology that is heading for obsolescence?
     
    Pushmi-Pullyu likes this.
  8. Pushmi-Pullyu

    Pushmi-Pullyu Well-Known Member

    Hey Martin, I appreciate your comments on this subject. You appear to be pretty well-informed here.

    Rather late in the discussion at TheEEStory forum, not long before it was shut down, at least one or two of the forum members best informed on the technical subjects (not me -- I would never be mistaken for an electrical engineer :)) said that altho it is theoretically possible to have capacitors with the energy density claimed by EEStor, it wasn't possible to do in in the manner they claimed. This seems to go along with what you're saying here.

    Well, you're exaggerating when you say the voltage does not drop as batteries approach being fully discharged. However, li-ion batteries show comparatively little drop until they are nearly exhausted.

    [​IMG]

    Caveat lector: Note the voltage drop is exaggerated on this chart because the bottom of the chart is cut off.

    But you're entirely correct about capacitors outputting voltage as a function of how fully charged they are. So the EV would need to have, as part of the PEM (Power Electronics Module), something that not only converts DC power to AC, but also acts as a transformer. I don't know if an EV's inverter can handle all of that, or if they'd need to add a voltage converter to the PEM. As I said, I'm no electrical engineer. But you seem to be implying that this would be difficult to engineer, and I do know enough to say that this is a problem which was solved more than a century ago. I think a voltage converter suitable for this application would be an off-the-shelf item.

    That's always the problem with tech that's in the early adopter stage. Do you buy now, and get the benefit of having the tech? Or do you wait a few years, and get something that is both easier to use and costs less? If I had it to do over again, I certainly would not have spent $1200 on a laserdisc player! But I would have bought a DVD player sooner than I did.
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  9. Martin Williams

    Martin Williams Active Member

    Whatever it is that supplies power to the motor will have to do it over a wide range of input voltage. There is no particular problem in doing this, but it has to be borne in mind.

    To use 90% of the power in a capacitor bank you will have to accommodate a range of voltages of about 3 to 1 for instance.

    When I converted my drill/screwdriver to supercaps, I built a little circuit to give me a linear indication of available energy. I used an analogue multiplier chip to do this, multiplying the voltage by itself, and it worked well. However, I never got round to fitting it as I could tell by the feel of the drill when it needed charging! There is such a thing as gilding the lily!
     
  10. Martin Williams

    Martin Williams Active Member

    I can't help laughing at the fact that billions of dollars have been thrown at improving Lithium Ion batteries, with some improvement but nowhere near the order of magnitude improvement needed and hoped for.

    Then some obscure chap fiddling about with contact lens material seeking to use it for some bioelectronic application decides to test the permittivity and finds it is hundreds or thousands of times bigger than anything else on the planet!

    If anything speaks for blue-sky research as opposed to goal-directed research this is it!

    I think the people holding the purse strings seem to confuse engineering with science. Yes, if you understand the science, billions of dollars will convert knowledge gained from a few bits of wire and a compass needle into a multi megaWatt electric motor.

    Unfortunately, those billions would be far from guaranteed to discover the simple (after the event) science needed to make it possible in the first place.

    As a Brit, I am extremely pleased that this was discovered here. I think it could be far, far more disruptive than any electric cars, be they running on hydrogen, lithium or Pixie dust!
     
  11. Pushmi-Pullyu

    Pushmi-Pullyu Well-Known Member

    That's rather odd, considering you're such a huge fan of hydrogen-powered fuel cell cars, for which nothing in the ballpark of an order of magnitude improvement is even physically possible! Talk about laughing; just look at all the billions of dollars that legacy auto makers have wasted on fuel cell cars! :confused: o_O

    And the continuing improvements in batteries -- not just li-ion batteries -- are progressing just fine; far faster than just about any other technology except microprocessors and computers.

    Your "laughter" rings rather hollow... and desperate.
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  12. Martin Williams

    Martin Williams Active Member

    The point is that lithium batteries remain stuck at a few percent of the energy density of the humble gas tank after all the effort devoted to them. Petrol, by comparison, provides about 12,500 Watt hours per kg. The best you can do with a practical battery pack, with all the heating and cooling to keep it stable, is well under 200 Wh per kg. The Tesla 3's pack is about 150 Wh/kg for instance. If you call that 'just fine' then you are very easily satisfied.

    The idea of a devoting a third of the weight of a car to store the energy it needs to make it go seems to me crazy anyway.

    And now capacitors look as if they may overtake them! This certainly makes me smile particularly as it was discovered by someone not even trying to store energy.

    Money spent on developing cars, by the way, be they hydrogen, battery, capacitor or petrol is ENGINEERING, not science. The two are often confused, but let us maintain the distinction here.
     
  13. Pushmi-Pullyu

    Pushmi-Pullyu Well-Known Member

    Yet another long-discredited "play" right out of the EV-Haters' playbook.

    Two points:

    1. About 70-80% of the energy in gasoline is wasted in a gas engine. So for an apples-to-apples comparison, throw away most of the energy in that fuel. The BEV's battery pack has considerably less energy, but wastes far less.

    2. To achieve energy-density with an ICE, a battery-electric vehicle does not have to match gasoline on a pound-by-pound basis. The BEV's motor weighs far less than the ICEngine, and the BEV's fixed-ratio reduction gear weighs far less than the gasmobile's transmission. Furthermore, various other Rube Goldberg kludges that the poor crippled gasoline engine needs, such as a muffler, catalytic converter, oil pump, etc. etc., are not needed at all by the BEV.

    The Argonne National Laboratory predicts the "Energy Density of EV and Gasoline Powertrains Will Converge" by 2045. Personally, I hope it will come much sooner!

    The limiting factors keeping BEVs from making gasmobiles obsolete -- as of yet -- no longer include energy density. Other factors such as battery cost and limitations on fast charging are limiting the appeal of BEVs.

    I certainly am satisfied with the energy density of batteries currently used in EVs. It's already good enough, but of course will continue to improve over time.

    I certainly hope they do! However, given all the claims we saw for revolutionary batteries and capacitors on TheEEStory forum, about one every two weeks over the course of years, I'd say the odds are pretty slim that this latest claim has any better chance than hundreds which we saw in the past.

    I truly feel sorry for those whose understanding of science and technology is so limited that they think there is a bright line between engineering and science. Sadly, that seems to be an attitude all too common among ivory-tower theoreticians who would never dream of getting their hands dirty with an actual experiment.

    As just one example, how far would rocket science have gotten if no engineering was involved? :cool:

    "In theory, there is no difference between theory and practice. But in practice, there is." -- Johannes Lambertus Adriana van de Snepscheut
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  14. Martin Williams

    Martin Williams Active Member

    Cars are much more efficient than that now. More like 40% or more in the case of diesels. And the waste 60% is often used to provide heating so it's not quite all waste is it. But the important point is that when you can carry plenty of energy, you really don't care how efficient the thing is. All extra efficiency will do for you is to reduce the running cost, and even ICE cars are easily affordable as the enormous number of them shows. Most of us would like to pay less, certainly, but evidently not if they have to sacrifice convenience for it.

    As to weight, the fact is that half a ton of battery plus all the cooling and heating equipment to keep it working properly weighs a comparable amount to the ICE engine. Go look at the weight of comparable ICE and BEV cars. If the two achieve parity in 2045 I will consider buying one. Perhaps. At the moment they are nowhere near. It is a big 'If' in my opinion. In 150 years batteries have achieved a fivefold increase in energy density (from lead acid to lithium ion) To become comparable to diesel or petrol they need somewhere between ten and a hundredfold more! That is 'unlikely' in my book.

    YOU may well be satisfied with the energy density of batteries now. Few are, however. I have never met anyone who would not like to be able to charge his cellphone in seconds, once a week or month for instance. And judging from the poor sales of BEVs, They are not acceptable to 98 out of 100 car buyers, who find worrying about batteries hassle they can do without.

    The difference between the Estor capacitor's magic dielectric and the new supercapacitor dielectric is that the latter works. Demonstrations have been given and there is no secret woo-woo formula. The material used is known across the world! Estor was an obvious and complete scam from day one. Nobody with a passable grasp of physics or electronics would have taken them seriously. Fortunately for the Estor scammers, there are plenty of uninformed idiots around!

    All the science in rockets has been known since Newton formalised the physics behind it. Also, people have been making rockets in China for thousands of years. What you call 'rocket science' isn't science at all. It is engineering. And most of the fundamental development was done by Germany in the development of the V2 rocket. The space race added virtually nothing to the physics of rockets, except to engineer bigger ones! An engineering achievement to respect, perhaps, but NOT a scientific one.

    And finally, you are wrong about 'theoreticians' who would 'not dream of dirtying their hands' with an actual experiment. Most theoreticians are folk who are better at throwing formulae around the page than doing experiments, but that doesn't preclude their suggesting experiments to prove or disprove their hypotheses or computing the accuracy of the measurement needed etc. The experiments are generally carried out by experimental scientists who do experiments because they are better at it than theory. Neither side, in my experience, has any contempt for the other. Both require considerable skill and hard work, but just in different ways.
     
  15. Pushmi-Pullyu

    Pushmi-Pullyu Well-Known Member

    I'm ignoring at least 3 or 4 of your recycled false statements, but but this one I can't ignore. I think you're just trolling here; repeating assertions which have already been thoroughly disproven as though you still believed them. This not only exposes your EV-hater agenda, it also amply demonstrates you don't actually believe your own false statements.

    But to the point: Batteries have increased more than an order of magnitude in energy density since circa 1985, which is 33 years... more than twice the increase you're claiming in less than a quarter of the time you're claiming. So that's two false statements in one.

    [​IMG]


    [​IMG]


    Good example of a bait-and-switch argument. You were talking about energy density, now you've switched to charging speed. That certainly does need improvement. Current charging times are around 30-45 minutes for an 80% charge, and we need to get that down to about 10 minutes or perhaps slightly less. Fortunately, we can see that each new generation of EVs has significant shorter average charging time, so we're already well on the way to that goal.

    No, the difference is that you're taking the benefit of hindsight to proclaim "I new it all along!", while demonstrating exactly the same credulity and lack of skepticism about this new claim; exactly the same behavior seen so frequently by those showing their wishful thinking on TheEEStory forum.

    Shall I quote from the tens of thousands of posts to the now-defunct TheEEstory forum which said pretty much the exact same thing? Your belief has no effect on reality, just as there is no basis in reality for your belief that there is some magical way in which hydrogen fuel will be transformed into a practical fuel.

    If there have been public demonstrations of this new organic supercapacitor tech, then please do cite any report of such demonstration(s). As I already pointed out, the wording of the press release is "we are ready to demonstrate" the tech. No claim there that it has been demonstrated to any outsider.

    :confused: :rolleyes: o_O
    Well, I gave you enough rope to hang yourself there, and you certainly did, with enthusiasm! :cool:
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  16. Martin Williams

    Martin Williams Active Member

    The Model 3 battery pack exhibits an energy density of about 150Wh/kg Go check its weight and how much energy it can hold for yourself and stop accepting overoptimistic graphs from unreliable sources. The two graphs you exhibit don't even agree with each other for heaven's sake!

    And I DID mention a one-charge-a-month smartphone battery by the way. Perhaps you missed that.

    As an admitted one-time estor enthusiast yourself I suggest you consider the possibility that you are easily convinced by plausible arguments and should perhaps be more prepared to modify your beliefs in the face of a more careful examination of the facts.

    Also, I have already given a reference to a paper in which working capacitors using hydrophilic dielectrics with high energy density were produced. If you want to see more on demonstrations I suggest you look at http://www.supercapacitormaterials.com/ which contains links to them. I suggest the press presentation on 26 Feb. 2018 which shows photographs of them and gives some details of what can be done already may be understandable to you. Clearly, there is much to be done before they replace batteries, but at least the science is sound. A number of groups around the world are working on these things. That they exist and work is indisputable.

    Finally, I stick to my belief that building bigger and better rockets has resulted in no furthering of the science as formulated by Newton. For the speeds involved, it was not even necessary to invoke the modifications due to the work of Einstein! It is engineering, not science. It may have been used to deploy instruments designed to perform scientific experiment, but that is a quite separate thing. You might as well claim that a scientist travelling to work on a bus is performing 'bus science'.

    So I invite you to exhibit a single example of what you call 'rocket science'.
     
    Last edited: Mar 24, 2018
  17. Feed The Trees

    Feed The Trees Active Member

    Battery density in current BEV aren't a limiting factor per se in terms of the public thinking about it, but it is because you don't see 600 mile cars that totally obliterate range anxiety or super light crazy cars for the sport crowd.

    Density can be the cure all. Fast charging has it's natural physcial limits. There's only so many electrons that can flow per second. Then again as part k size increases the time to charge a reasonable portion of it for a few hundred miles drops.

    Sent from my Nexus 5X using Tapatalk
     
  18. Martin Williams

    Martin Williams Active Member

    I would suggest that a vehicle which is carrying a third of its weight as an energy store is problematical. That inevitably means limited range which the public IS aware of. I suggest also that decreasing capacity is something the public is aware of. But mostly I believe it is the loss of convenience that charging involves and the time it takes that is the worst disincentive.
     

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