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Improved High-Performance Energy Storage

Posted by ScuttleMonkey on from the electrons-in-a-volkswagon dept.

Physicists at the University of North Carolina have developed new improvements for high-energy-density capacitors that can store up to seven times as much energy per unity volume as common capacitors. "The amount of energy that a capacitor can store depends on the insulating material in between the metal surfaces, called a dielectric. A polymer called PVDF has interested physicists as a possible high-performance dielectric. It exists in two forms, polarized or unpolarized. In either case, its structure is mostly frozen-in and changes only slightly when a capacitor is charged up. Mixing a second polymer called CTFE with PVDF results in a material with regions that can change their structure, enabling it to store and release unprecedented amounts of energy."

13 of 129 comments (clear)

  1. Wrong University by jmcharry · · Score: 5, Informative

    From TFA, it is North Carolina State University. You are about to be set upon by wolves!

  2. Quite a Result by JamesRose · · Score: 3, Insightful

    I was wandering about this for some time, you look at any electronics board, the biggest things on them are chips, which are actually many many small components, and capacitors, which are disproportionately big in comparison to everything else which has been turned into miniscule gizmos integrated into everything else.

  3. polymers by wizardforce · · Score: 4, Informative

    CTFE Chlorotrifluoroethylene PVDF Polyvinylidene fluoride http://en.wikipedia.org/wiki/Polyvinylidene_fluori de

    --
    Sigs are too short to say anything truly profound so read the above post instead.
  4. Vaporware... by Rhys · · Score: 4, Informative

    Key phrase from TFA:

    "Their predictions of higher energy density capacitors are encouraging, but have yet to be experimentally tested."

    Call me when they're being produced in something resembling quantity. Yeesh.

    --
    Slashdot Patriotism: We Support our Dupes!
  5. major faux pas in /. description of article by Yonder+Way · · Score: 4, Informative

    The editors are asleep again. The summary says the discovery was made at University of North Carolina, which really surprised me because all of the good engineering is happening at North Carolina State University.

    It might seem like a trivial slip but to those around here there is a pretty huge difference.

    Oh yeah, and DUKE SUCKS.

  6. Coppertops? by Alyred · · Score: 4, Funny

    Well, guess all those AIs in the matrix won't need us any longer. Goodbye, reality!

  7. Great... by Valdez · · Score: 5, Funny
    Now first year EE students are going to actually *die* when they forget their cap is still charged.

    It was bad enough to just get your shiny new needlenose pliers welded together. =/

  8. Shipstones by Anonymous Coward · · Score: 4, Interesting

    In his novel Friday Robert Heinlein described a fictional device called a "Shipstone". This was an ultra-super electricity storage device.

    Supposedly, the shipstone had a dramatic positive effect on the world. It was no longer a problem to get electricity from where it's made to where you need it. Big solar power systems were put in areas that get lots of sun, for example. Cars would run on Shipstones, and instead of gas stations, they had stations where you could swap the discharged Shipstone from your car for a fresh, fully-charged one.

    I have been wondering if these new ultracapacitors might someday become practical "Shipstones". How close are ultracapacitors to, say, powering a car?

    Can you drain the power slowly from an ultracapactor, to run a car for a few hours, or do you have to drain it quickly? Does charge leak out slowly over time from an ultracapacitor, or can you make it fairly inert?

    1. Re:Shipstones by cartman · · Score: 3, Interesting

      I have been wondering if these new ultracapacitors might someday become practical "Shipstones". How close are ultracapacitors to, say, powering a car?

      I should start by saying that I'm not an EE, however I've done some reading on this topic.

      Ultracaps are still far from being practical for powering a car. Right now the best Ultracaps store 5-10 Wh/kg, which means they could only store enough energy to power a car for a few miles. Furthermore, the price of the ultracaps is about 10x too expensive for the car to be within the price range of what most consumers expect.

      HOWEVER, Ultracaps have seen dramatic and encouraging improvements during the past 10 years. Ultracaps have decreased in cost/kjoule by a factor of about 3 over the last 5 years, and have seen dramatic improvements in energy density. At the current rate of improvement, in about 10 more years Ultracaps will be usable for plug-in hybrids that cost about the same as conventional vehicles and can run for 10-20 miles on electricity alone. Unlike batteries, ultracaps can be recharged extremely quickly and will not require replacement after repeated recharging.

      Can you drain the power slowly from an ultracapactor, to run a car for a few hours, or do you have to drain it quickly? Does charge leak out slowly over time from an ultracapacitor, or can you make it fairly inert?

      You can drain the ultracap slowly. However ultracaps can be more dangerous than batteries since they can discharge all their energy instantaneously.

  9. Re:What I want to know is ... by ScrewMaster · · Score: 3, Funny

    Thanks. Who's the President of the U.S. again? Never can remember. And my girlfriend is having this problem with her ... uh, nevermind about that.

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    The higher the technology, the sharper that two-edged sword.
  10. *yawn* only seven times? by syukton · · Score: 4, Informative

    Call me when they're competing with MIT's carbon nanotube based ultracapacitors. Conventional ultracapacitors can achieve an energy density of 6Wh/kg, but the CNT ultracapacitors being researched and developed by MIT are claimed to achieve an energy density of 60Wh/kg (or, let's say, ten times more than this "new" capacitory developed by North Carolina State University).

    Overview: http://lees-web.mit.edu/lees/projects/cnt_ultracap _project.htm
    More-detailed Poster (PDF): http://lees-web.mit.edu/lees/posters/RU13_signorel li.pdf

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    Reinvent the wheel only at either a lower cost, greater effectiveness, or your own personal enrichment and satisfaction.
  11. why compare to "common capacitors"? by Eric+Smith · · Score: 4, Interesting

    seven times as much energy per unity volume as common capacitors
    It may well be a breakthrough, but I'm not impressed with that particular claim. Aerogel capacitors (e.g., Cooper Bussman PowerStor series) and Electric Double Layered Capacitors (e.g., Panasonic SG series "gold capacitors") already have at least 2000 times higher energy storage density than common capacitors.
  12. Re:battery replacements? by CaptainPatent · · Score: 4, Interesting

    Capacitors are rarely meant to be a battery replacement. They are meant to be used for fast storage and release of energy on the order of milli- or microseconds. The chemical reaction that occurs in batteries is far too slow to produce a resonating RLC circuit, or even power a bright camera flash where a capacitor is used in parallel with the battery. Likewise, the Capacitor has a much smaller operating output than a battery in general and they tend to leak thus requiring a load just to keep them at full charge.

    The excitement isn't in the fact that they may be a battery replacement, it's that they can store a ton of energy for many other electrical uses.

    --
    Well, back to rejecting software patent applications.