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New Electrode Lets Batteries Charge In 10 Seconds

Posted by samzenpus on from the greased-electricity dept.

Al writes "A new lithium-ion electrode allows batteries to be charged and discharged in 10 seconds flat. Developed by Gerbrand Ceder, a professor of materials science at MIT, it could be particularly useful where rapid power bursts are needed, such as for hybrid cars, but also for portable electronic devices. In testing, batteries incorporating the electrodes discharged in just 10 seconds. In comparison, the best high-power lithium-ion batteries today discharge in a minute and a half, and conventional lithium-ion batteries, such as those found in laptops, can take hours to discharge. The new high rate electrode, the researchers calculate, would allow a one-liter battery based on the material to deliver 25,000 watts, or enough power for about 20 vacuum cleaners."

17 of 348 comments (clear)

  1. 20 vacuum cleaners... by Anonymous Coward · · Score: 5, Funny

    ...how many libraries of congress per square inch is that, again?

    1. Re:20 vacuum cleaners... by NeverVotedBush · · Score: 5, Informative

      I don't think the ability to drain the battery in such a short time is the point. It's in delivering high current easily.

      Lots of loads pull a lot of current initially or periodically. One example would be an electric motor since they talk about applications such as hybrids. The stall current is limited by the resistance of the windings but once it spins up, reverse voltage in the motor limits the current to much lower values. If it was a motor under a heavy load, the current could be much higher.

      Another point is that in any high current circuit, the power wasted in the circuit as heat can be very high. It's current squared times resistance. With batteries that have a high internal resistance, that power heats the battery and is also power that's wasted. With a high current delivery capability, these would have very low internal resistance and under heavy loads, the batteries would run cooler and would be able to deliver more power to the actual load instead of throwing it away as heat.

      This really is an accomplishment and a valuable one.

      Just to illustrate battery self heating - if you ever get stranded in extreme cold because your battery doesn't have the power available to turn the engine over, just turn on the headlights for a while. It's a medium load but will heat the battery from the inside due to internal resistance and make the battery better able to start the car. This really works.

    2. Re:20 vacuum cleaners... by Snowblindeye · · Score: 5, Informative

      what the heck is the point of a battery can run 20 vacuum cleaners, for only 10 seconds?

      But it also means that you can *charge* it in 10 seconds. How nice it that. One problem for plug-in electric cars is that they take long to charge. If charging it doesn't take longer than filling up a tank of gas, that would be a step forward.

    3. Re:20 vacuum cleaners... by fractoid · · Score: 5, Interesting

      Um, for starters, you're not going to be plugging all those cars in at the same time if each one's only plugged in for 10 seconds.

      Secondly, generally EV-sized batteries are fast-charged by using a 'dump pack', an identical fully charged pack of batteries that can supply as much current as the flat one can eat up. The important number is the continuous current draw, not peak.

      That's what makes small, high-current batteries so good. Imagine a car window motor which pulls, say, 5 amps at 12 volts. You need to run 5amp wiring to it. But assume that the motor only needs to run for a few seconds at a time, very infrequently - instead of running 5 amp wiring, you can simply put a battery next to the motor that's sufficient to run it for a minute or so, and trickle charge the battery over the car's CAN bus.

      Another use (actually this is one I read about where ultracaps are useful) is making a hard drive that doesn't lose data when the power drops during a write operation. Basically the cap would store enough energy for the drive to detect loss of external power, finish writing its buffer, and park itself before it ran flat.

      --
      Rampant carbon sequestration destroyed the Dinosaurs' tropical paradise. I'm here to help repair the damage.
  2. 20 vacuum cleaners for 10 seconds? by DigitalReverend · · Score: 5, Funny

    That sucks.

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    I read Slashdot for the headlines, because the headlines, unlike the articles, are usually original and never duplicated
  3. Good for cars? by NaCh0 · · Score: 5, Funny

    Great, by the time I have backed out of the driveway I'll need to recharge it.

  4. Re:charging by yincrash · · Score: 5, Informative

    after reading the article, fast charging has not been developed. the article writer only says that it may be possible, w/o citing any source regarding that claim.

  5. Re:fast enough for a by sgbett · · Score: 5, Interesting

    first thought?

    Railgun

    --
    Invaders must die
  6. c'mon, boys by Anonymous Coward · · Score: 5, Funny

    a page of comments and no one has yet said:

    "10 seconds? the average /. geek discharges faster than that"

    sigh.

  7. Armageddon by GottliebPins · · Score: 5, Funny

    Wow, now we can expect to see spectacular laptop fires hot enough to burn through an engine block. Where can I get some of those batteries? Sony?

  8. Think about it by jeffmeden · · Score: 5, Interesting

    Actually, the big thing about electric driving isn't getting started in the first place, it's reclaiming the energy when you have to stop (at least for inner city driving.) If you have a battery that is bordering on a supercapacitor to dump energy into, you can reclaim nearly all of the stopping energy into the battery to use to start again. Given that there are 745 watts/hp, a battery capable of a charge rate of 25KW gives you 33 horsepower of braking capacity with one cell. Get 3 of them in a car and you can reclaim 100hp during a stop, which would be good for all but the most grueling emergency stops (depending on the weight of the car).

  9. Re:fast enough for a by momerath2003 · · Score: 5, Informative

    You probably would want capacitors for those, with other pulse-shaping devices. In fact, this is what they actually do. Ten seconds of discharge is way too slow for a rail gun.

    --
    I had but a simple dream, to destroy all humans.
  10. Re:charging by Repton · · Score: 5, Funny

    All you need is a wall socket that can deliver 25,000W!

    Note to self: pick up some 100A fuses on the way home.

    --
    Repton.
    They say that only an experienced wizard can do the tengu shuffle.
  11. Re:fast enough for a by rsborg · · Score: 5, Funny

    I thought of writing I disclaimer saying as much, but my submit button discharged too fast.

    You know they have drugs for that. The blue pill and all.

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  12. Re:fast enough for a by rubycodez · · Score: 5, Insightful

    but for a man-portable railgun, the batteries are used to charge the capacitors, all in the back pack.

  13. Wrong analogy... by NotQuiteReal · · Score: 5, Funny

    You should think more along the lines of a Beowulf Cluster of Roombas.

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    This issue is a bit more complicated than you think.
  14. Re:charging by Rufty · · Score: 5, Funny

    In the fuse draw of a local college electronics lab I found a length of 6inch nail lovingly cut to length with cleaned ends, painted round the middle with the designation "10000A, slow-blow" (Apparently one of the techs had a dead scope that couldn't be powered up - it just blew the fuse. Hence the nail. Bung it in and now you know where the hard short *was*. It's the melted patch with the smoke coming out...)

    --
    Red to red, black to black. Switch it on, but stand well back.