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Power Technology

Ultracapacitors Soon to Replace Many Batteries? 415

einhverfr writes "According to an article in the IEEE Spectrun, the synergy between batteries and capacitors — two of the sturdiest and oldest components of electrical engineering — has been growing, to the point where ultracapacitors may soon be almost as indispensable to portable electricity as batteries are now. Some researchers expect to soon create capacitors capable of storing 50% as much energy as a lithium ion battery of the same size. Such capacitors could revolutionize many areas possibly from mobile computing (no worries about battery memory), electricity-powered vehicles, and more."
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Ultracapacitors Soon to Replace Many Batteries?

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  • HEY! (Score:5, Funny)

    by mboverload ( 657893 ) on Sunday November 04, 2007 @07:48PM (#21236023) Journal

    I want my friggin 15 hour battery life laptop first! You promised!
    • Microsoft taketh away.
      • Re: (Score:3, Interesting)

        by dintech ( 998802 )
        Why is this off-topic? It's quite relevant. Why spend all this time developing energy efficient hardware without developing energy efficient code? Of course Microsoft aren't the only culprits of this. McAfee, I'm looking at you...
    • Yeah. And flying cars. They promised us flying cars.
  • by kcbanner ( 929309 ) * on Sunday November 04, 2007 @07:48PM (#21236025) Homepage Journal
    ...your fingers may become part of the capacitor.
  • by Anonymous Coward on Sunday November 04, 2007 @07:49PM (#21236041)
    Do they burst and leak ballast (the fluid between the plates of a capacitor) like the capacitors commonly used in cheap motherboards today? I've heard that this ballast can be a serious health and environmental hazard. Of course, we all know that it often destroys motherboards by causing them to short circuit.
    • by Sanat ( 702 ) on Sunday November 04, 2007 @08:06PM (#21236163)
      In the early 60's i was working part time at a TV repair shop to augment my military paycheck. I was working on one of those old huge TV's in the wooden cabinet type of thing. i had traced the problem to a paper electrolytic of fair proportion.

      I changed the capacitor and confidently looked at the waveform on the scope knowing now that there would be no more ripple on the line but to my amazement there was even more ripple. I looked closely at my installation job noting it was across the right terminals and the polarity was correct.

      I pulled my head out of the TV cabinet to look at the schematic to envision what else might be wrong when the capacitor blew up like a small bomb leaving a boiling hot liquid paste where moments before my head was peering.

      It turned out that the paper cylinder was installed backwards on the capacitor reversing the positive and negative terminals.

      Even if the paper cylinder was backwards... one can still note the metal case of the capacitor being the negative terminal. I failed to do this.

      This occasion added a new check I made each time for every capacitor installed after that.

    • What a stupid thing to say. Modern capacitors are very different than old sturdy capacitors, and also from the less-than-surdy electrolytics which would often explode. The new caps have far better charge density and use very sophisticated dielectrics.

      Saying that modern capacitors are like old ones is like comparing a carbon-fiber poles to a pole made by cutting down a tree.

      One of the biggest challenges with large capacitcnce devices is getting rid of the effective series resistance (ESR). High energy capaci

    • by moosesocks ( 264553 ) on Sunday November 04, 2007 @10:44PM (#21237221) Homepage
      Capacitors can be filled with many different dielectrics to improve their capacitance.

      The most common thing you see are electrolytic capacitors, which can indeed burst if they're of extremely poor quality (and cause an environmental hazard along the same lines) -- but of course, saying that is true of many many things. Take paint for instance -- we cover everything in it, and it's generally safe, with only a few exceptions like lead paint, which will make you sick, or the stuff they coated the Hindenberg with, which could also be used as rocket propellant...

      Modern electrolytics are much better, although their operating characteristics aren't the greatest -- they have a high capacity, and that's about it.... they're not at all reliable or tolerant of varying operating conditions. Fortunately, many applications don't require this...

      You can use all sorts of other things inside a capacitor: paper, glass, ceramic and kevlar are used to name a few, or you can forego the dielectric completely, and put a vacuum between the two plates.

      Oh, and supercapacitors don't use electrolyte as the dielectric. That's not to say they won't go boom -- I have no idea how they operate, but they're not filled with the same stuff as what you're thinking of -- if they were, they'd still just be plain old unremarkable electrolytic capacitors.
  • by Anonymous Coward on Sunday November 04, 2007 @07:49PM (#21236045)
    Perhaps they can use this technology to make more lethal tasers. Or at least tasers that give some good burns.
    • Re:Better tasers? (Score:5, Informative)

      by hedwards ( 940851 ) on Sunday November 04, 2007 @09:04PM (#21236545)
      Tasers already use capacitors. They are just used to store a temporary charge until it is released.

      The capacitor is charge via the battery, and the charge is released over a shortened interval. Same deal with a camera flash.

      The could already make tasers lethal in nearly all cases if they wanted to, but the point of them is that they aren't lethal in most cases.

  • obvious (Score:4, Funny)

    by User 956 ( 568564 ) on Sunday November 04, 2007 @07:50PM (#21236047) Homepage
    Some researchers expect to soon create capacitors capable of storing 50% as much energy as a lithium ion battery of the same size

    Yes, but are they as incendiary as a SONY battery of the same size?
  • Vaporware (Score:5, Insightful)

    by mark-t ( 151149 ) <> on Sunday November 04, 2007 @08:00PM (#21236125) Journal

    We think--and our work so far supports our theory--that by doing so, we can create a device that can hold up to 50 percent as much electrical energy as a comparably sized battery.
    Why does stuff like this get so much press when it's actually nothing resembling anything that really happened?
  • by schnikies79 ( 788746 ) on Sunday November 04, 2007 @08:00PM (#21236127)
    Why would I want to double the size of my battery to achieve the same power output as a Li-ion?

    I could see this in devices where you need a high current for a short time, but not for slow drain devices. I personally want a battery (or whatever) that last longer than a Li-ion or Li-polymer in a notebook or phone while staying the same size or going smaller.
    • For some people, a smaller battery capacity would be made up for by the potential of fully recharging it in under a minute.

      There's already a power screwdriver that does this...I don't recall the brand. It may have less capacity than a Li-ion or NiMH driver, but you can recharge from empty to full in 20 seconds.
      • Re: (Score:3, Insightful)

        by timeOday ( 582209 )
        Exactly. I would absolutely prefer a capacitor over a battery for power tools such as a drill. Currently I still use a corded tools because I don't use them every day, so I need them to last for a couple decades, and batteries don't do that. More important, if you're in the middle of a job and the battery dies, it's over. With a capacitor, pop it in while you go get a drink and you're ready to go again. Another example is a cordless shaver, I use it a little each day, so extreme battery life is unneces
      • Re: (Score:3, Insightful)

        by Shados ( 741919 )
        Perfect for things like TV remote, electric shavers, screwdrivers (as you mentionned), computer mice, wireless phones (not cells), console controllers and just about anything that would benifit from being wireless, but is always close to a power outlet. Looking around right now, thats the majority of things that use batteries that I have. Aside cellphones, lap-tops and pocket PCs... most things could do with a lower capacity and faster charge time, definately.
      • Re: (Score:3, Informative)

        by compro01 ( 777531 )
        that's the coleman flashcell []?.
    • by erayd ( 1131355 ) on Sunday November 04, 2007 @08:22PM (#21236273)
      But the incredibly fast charge time would be the killer app for this. Sure, it only lasts half as long, but when you can charge it in a minute or two does that really matter?
      • Won't the size of the fuse in the home circuit limit the charging rate?
        • by fabs64 ( 657132 )
          Yes... to around (from memory) 2,400 w/H My laptop charger here says it's managing to suck in a grand total of... 65 w/H, a significant improvement I would say.
        • yes and no. modern batteries for laptops are ~55 watt hours. but they at run at ~5 volts roughly 11 amps for an hour if memory serves. but at 120volts that drops down to 0.5 amps. that's a 60 watt light bulb at 130 volts

          my math is off as I am not bothering to look up the exact calculations but it's close. It's why transmission lines run at 1000 volts, or 15 thousand volts. they don't need to carry the amperage.
          • but at 120volts that drops down to 0.5 amps.

            You've proven you can charge a laptop battery in an hour. Now multiple 0.5 amps by 60 to see that it'll take a 30 amp outlet for 1-minute charging.
        • Yep. (In Australia) a standard 10A wall socket can pull 2400W. I think you could charge your shaver pretty quickly with that power input...
      • But the incredibly fast charge time would be the killer app for this.

        I don't see it. If there are available outlets, I'd be using them, rather than my battery. (High-power) electrical outlets don't magically show up on an airplane, halfway through the flight and disappear 5 minutes later...

        when you can charge it in a minute or two does that really matter?

        To recharge current laptop batteries in 1 minute on 120V would require a 30 amp outlet, while standard outlets max-out at 15 (and I don't recommend maxin

    • Why the size problem?
      The battery of a notebook or phone is only a small part of the total volume and weight of the device. I would be overjoyed if they simply quadrupled the size of the (existing technology)battery and gave me 4 times the capacity.

      • I would be overjoyed if they simply quadrupled the size of the (existing technology)battery and gave me 4 times the capacity.

        Some people are easy to please: buy 3 spares.

    • by PseudoThink ( 576121 ) on Sunday November 04, 2007 @08:47PM (#21236425)
      The nice thing about capacitors is that they charge orders of magnitude faster than batteries. If you could plug your phone/PDA/etc. into any wall socket and have it fully charged in a few seconds, would you really need a power source for it that would last for days? Certainly yes, for camping trips perhaps. Ultracapacitors would introduce new ways of using portable devices.
    • Why would I want to double the size of my battery to achieve the same power output as a Li-ion?

      To get a device that won't wear out and can be recharged in minutes (or even seconds, if you can pump enough power in) instead of hours?

      Instead of swapping out your battery, plug it in for a few minutes.
    • Weight. Ultracaps are incredibly light compared to batteries with the same charge capacity, meaning no more seven pound "portables".

      I'd trade more frequent charges (each taking a couple of minutes, total, due to the advantageous storage properties of a cap) for that.
  • I've got an idea! (Score:5, Insightful)

    by Anonymous Coward on Sunday November 04, 2007 @08:07PM (#21236171)
    How about not writing such obscenely bloated software that it needs a mainframe-on-a-chip to show an address book?
    You want to save energy? You want to reduce cost? You want to reduce carbon footprint? It's not by making yet another technology, it's by refining what we already have. We don't need Javascript code that takes seconds to execute a simple text display on a multi-GHz processor. Start there. And we won't need capacitors with the energy density of an explosive to run a freaking phone.
    • Re: (Score:2, Insightful)

      "It's not by making yet another technology, it's by refining what we already have."

      We don't need to build huts, we've got CAVES! Actually, we don't even need the caves, we've got trees! Hell, why even leave the oceans, we've got WATER!
    • by nurb432 ( 527695 )
      Good luck with that. While i agree totally, that would not keep us on the perpetual upgrade treadmill that modern day corporate wants to maintain.

      Unless/Until resources disappear, the concept of efficiency will not return.
  • by dltaylor ( 7510 ) on Sunday November 04, 2007 @08:18PM (#21236235)
    Rapid energy storage, with very low effective series resistance, is perfect for regenerative braking, and for burst acceleration. If a vehicle starts with full batteries and capacitors, then uses the capacitors first in acceleration, they would be discharged when braking was required, allowing them to rapidly store the power from the motor/generators. The batteries (and fuel cell or combustion engine), then are sustained energy for overcoming losses, powering accessories, and long uphill grades.
  • by LingNoi ( 1066278 ) on Sunday November 04, 2007 @08:25PM (#21236303)
    Could someone explain this all to me please?

    Are Ultra capacitors like flux Capacitors that you can use to go through time once you're travelling at 88mph? If so I don't think this will be very efficient at all since they require 1.42 Gigawatts!
  • RTFA (Score:2, Insightful)

    by MacTO ( 1161105 )
    It isn't necessarily about laptops and digicams, though it may be used there. The exciting stuff involve the ability to charge and discharge fast, and hopefully they are chemically stable so that they last a long time. Something like that could be used to harness the energy of a stopping train, the take that energy and put it right back into starting that train into motion again. Imagine using that for subways or light rail. I could also see it being used to lighten power distribution problems for such
  • Royalties (Score:2, Insightful)

    by McFortner ( 881162 )
    Isn't somebody gonna owe royalties to Philip Jose Farmer for the idea of the batacitor (first seen in the Riverworld book The Fabulous Riverboat?
  • by guidryp ( 702488 ) on Sunday November 04, 2007 @08:57PM (#21236501)
    The best ultra caps are still off by an order of magnitude.

    I have been hearing how eestor would have its ultra caps in cars in 2006, then 2007, and I can only assume 2008 now. Not only are they not in cars, they haven't demoed as much as a since cell. Yeah I know it is not just eestor, but I am getting tired of empty hype.

    I love hearing about technology, but at some point, they get to the "put up or shut up" point. That point has past for me.
  • I like how they always fail to mention the one issue that I dobt will ever be overcome with cap batteries. They can explode quite easily with a bit of shock releasing all stored energy (or just because if there are any impurities). Not to mention if overcharged they will release all of that charged up energy making the Sony Li-Ion battery explosions look like a gimp firecracker.
  • by Dorceon ( 928997 ) on Sunday November 04, 2007 @09:06PM (#21236567) read that title as "Utahraptors soon to replace many batteries"
  • by CustomDesigned ( 250089 ) <> on Sunday November 04, 2007 @09:20PM (#21236661) Homepage Journal
    TFA talks about flywheels "needing a heavy and complicated transmission". That was flywheels 20 years ago. Todays ultra flywheels are magnetically suspended in a vacuum, rotate at ultra high rpms (since stored energy increases with the square of rotation speed), and use the same magnets to spin up and down, storing and releasing electricity. The resulting energy density is better than either batteries or ultra-capacitors. The drawback to ultra-flywheels is that so far they work well for something the size of a bus (and are being used for that purpose), but haven't been built small enough yet for a car, much less a laptop. They also don't like to be rotated in 3 dimensions. One promising application of ultra-flywheels is storing electricity for power companies, and releasing it during peak demand.
  • by Anonymous Coward on Sunday November 04, 2007 @09:45PM (#21236827)
    This news post excited me at first. Using ultracapacitors currently on the market you would something like 3Kg of big fat high quality ultra capacitors (3 or 4 at about $250US a piece) and a high-efficiency voltage boosting circuit to power your notebook computer for a time period comperable to a standard 2.5 to 3hr LiIon battery. Ultracapacitors, Supercapacitors, and other high-density high-capacity over physical space capacitors have a very delicate construction of internal plates (usually in the form of ribbons in a very tight roll with some sort of gel in between). Because of the special gels used and the tight and fine construction within them they usually have a tolerance somewhere between 2.5 and 3 volts or so. Your notebook computer probably runs off of 12V internally.

    One thing to note is that capacitors can charge almost instantly. So if their claims are true going from a 3hr battery to a 1.5hr capacitor of the same size would have the benefit that you could charge up very quickly. For me I'd take the 1.5hr capacitor simply for this, as I'm usually in transit less than an hour when using my notebook on battery power. For people who need more extended periods there are always external batter packs (which I use when I go on international flights or other long trips).
  • by noidentity ( 188756 ) on Sunday November 04, 2007 @10:13PM (#21237023)
    See Wikipedia's entry on memory effect [], also Dan's Quick Guide to Memory Effect []. In short, "memory effect" is now used to refer to any reduction in a cell's capacity, for example due to aging or normal use. I doubt you can find any capacitors that don't also have reduced capacitance years later.

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