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Step Toward Liberating Electronic Devices From Their Power Cords

Science_afficionado (932920) writes "A new type of supercapacitor that can hold a charge when it takes a lickin' has been developed by engineers at Vanderbilt University. It is the first 'multi-functional' energy storage device that can operate while subject to realistic static and dynamic loads — advancing the day when everything from cell phones to electric vehicles will no longer need separate batteries. These devices could make it possible to design electrical devices that are not limited by plugs and external power sources."

77 of 130 comments (clear)

  1. I hate it when; by Mr+D+from+63 · · Score: 1, Troll

    A supposedly intelligent author feels the need to say "ten times less"

    1. Re:I hate it when; by Twinbee · · Score: 2

      "Ten times more" would mean multiply by ten, so it makes sense that "ten times less" means divide. It's consistent, and that's the main thing.

      --
      Why OpalCalc is the best Windows calc
    2. Re:I hate it when; by Mr+D+from+63 · · Score: 1

      "Ten times more" would mean multiply by ten, so it makes sense that "ten times less" means divide. It's consistent, and that's the main thing.

      If 10=more and 5=less, which is greater, 10 times less or 11 times less?

    3. Re:I hate it when; by Twinbee · · Score: 1

      That's like saying if 10=more and 5=less, which is greater, one tenth, or one eleventh.

      --
      Why OpalCalc is the best Windows calc
    4. Re:I hate it when; by Bing+Tsher+E · · Score: 1

      'the energy of current' is a really weird and unreal concept. Did you take some phy ed class instead of physics?

    5. Re:I hate it when; by Megane · · Score: 1

      Ten times more would be x + 10x = 11x. Ten times as much would be 10x.

      --
      #naabhaprzrag, #sverubfr-000, #agi-fcbafberq, negvpyr[pynff*=' negvpyr-ary-'] { qvfcynl: abar !vzcbegnag; }
    6. Re:I hate it when; by Mr+D+from+63 · · Score: 1

      No. Saying 10 times less implies less has a value. If less has no value, then 10 times less = 0.

      Its not a matter of knowing what the author meant. Its simply a matter of correctness. Don't submit anything to a science journal or a legal entity, and you'll be just fine.

    7. Re:I hate it when; by MightyYar · · Score: 4, Insightful

      Yeah, but English is all about context. The statement "Supercapacitors store ten times less energy than current lithium-ion batteries, but they can last a thousand times longer," is unambiguous in this context because we know that the energy storage is not negative. Language would be really boring if everyone spoke as if they were programming a computer. In fact, we have precise language in various fields, and it generally sucks to read. Imagine if everything were written in legalese!

      --
      W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
    8. Re:I hate it when; by Twinbee · · Score: 1

      That's all well and good, but what rolls off the tongue quicker and is less ambiguous for other numbers? For example, "one three hundred and seventieth", or "three hundred and seventy times less"? The latter is clearly superior.

      --
      Why OpalCalc is the best Windows calc
    9. Re:I hate it when; by Twinbee · · Score: 1

      Hmmm... how about "ten times greater" or "ten times higher"? Would you be happier with "ten times lesser" or "ten times lower" then?

      --
      Why OpalCalc is the best Windows calc
    10. Re:I hate it when; by Twinbee · · Score: 1

      Would you be happier with "ten times lower" or "ten times lesser" at least?

      --
      Why OpalCalc is the best Windows calc
    11. Re:I hate it when; by thaylin · · Score: 1

      No, 10x is 9 times more than 1x.

      You can do a simple mathematical proof

      Let x = 10

      1x = 10

      10x = 100

      According to your logic 10x +1x = 100, but it does not 9x + 1x = 100.

      The problem is the word MORE, which means additional. If you have 10x additional you have to add it back to the base amount

      --
      When you cant win, ad hominem.
    12. Re:I hate it when; by Dcnjoe60 · · Score: 1

      or you know, you could use the mathematically correct "one tenth".

      Except that one tenth is not mathematically the same as 10 times less. There is no such thing as x times less. If you have ten apples how many apples must I have if I have 10 times less? There are two possible ways to look at this. Using a number line with 0 in the middle and negatives to left and positives to the right, I would move 100 apples (10 times 10) to the left, because I have less and I would have the mathematically correct, but physically impossible -90 apples.

      The other way, which is probably what the author meant is as you suggest one tenth. However, if I have one tenth of the ten apples, meaning I have one apple and apples are the unit of measure (in this case), technically I have 9 apples less. In other words, 10 is ten times more than 1, but 1 is only nine times less than 10.

      While I think that you are correct and one tenth is what the author meant. Using ten times less, at least mathematically, means something totally different.

    13. Re:I hate it when; by RatherBeAnonymous · · Score: 1

      Consistent? Not really. What if someone writes "0.1 times less". Strictly speaking, X times 0.1 is one tenth of X and would be the correct interpretation. But modern vernacular, the "less" indicating division, it would be X divided by 0.1 equaling 10X.

      On a side note, what ever happened to teaching journalism students basic math?

    14. Re:I hate it when; by Mr+D+from+63 · · Score: 1

      No, i"d be happy with the correct, "one tenth", or "a tenth", or "10 percent of", or any other grammatically and mathematically correct way of saying it.

    15. Re:I hate it when; by morgauxo · · Score: 1

      Me too!!!!

    16. Re:I hate it when; by Twinbee · · Score: 1

      Well then there's nothing more I can really say apart from: The author's way of using "less" I think is fine. Language evolves all the time, and I think this usage is not only perfectly acceptable, but is consistent, and even an *improvement* in many cases (since for other numbers, it's potentially awkward - see my other post).

      As someone else pointed out, it's even MORE appropriate given what he said in the sentence: “Supercapacitors store ten times less energy than current lithium-ion batteries, but they can last a thousand times longer.". That's a good way to contrast 10 with 1000, and it's said eloquently, making perfect sense to probably 99.9% of the population.

      --
      Why OpalCalc is the best Windows calc
    17. Re:I hate it when; by bluefoxlucid · · Score: 1

      According to "The Elements of Style" by Strunk and White, "one tenth" is both correct and better. "One tenth" is shorter, thus a stronger statement.

    18. Re:I hate it when; by Twinbee · · Score: 1

      Since it's not a scientific paper, but an article for the general public, "0.1 times less" would never get printed, is not in common usage, and so is technically undefined as of yet, but I see your point.

      The point is, even amongst those who are compaining, I bet not ONE slashdotter misinterpreted that sentence in the original article.

      --
      Why OpalCalc is the best Windows calc
    19. Re:I hate it when; by RatherBeAnonymous · · Score: 1

      By saying X times "more" or "less", the "more" or "less" or "greater" or "lesser" the writer adding is a qualitative assessment and not a mathematically significant descriptor. The correct way to write it "10 times" or "one tenth", any increase or decrease is obvious to anyone with a grade-school education and consistent for mathematically experienced readers. Alternately, if the author wants to state the obvious they can say "increased to 10 times" or "reduced to one tenth". Journalist used to write like that, and I recall being taught to write this way in school.

      I sympathize with Megane on the issue of x + 10x

      When speaking about percentages, to say 100% more, we are saying 2 times. The original 100% plus 100% = 200%, therefore 2 times. To say 1000% more is equal to x + 10x. Mathematically percentages work exactly like multiplication, so "10 times more" should mean x + 10x

    20. Re:I hate it when; by Anonymous Coward · · Score: 1

      or you know, you could just improve your communication skills, dumbass

    21. Re:I hate it when; by rjstanford · · Score: 1

      That's all well and good, but what rolls off the tongue quicker and is less ambiguous for other numbers? For example, "one three hundred and seventieth", or "three hundred and seventy times less"? The latter is clearly superior.

      In that example? "A quarter of a percent", by a long shot.

      Look, if we don't have to be accurate, then we can use much, much quicker and smoother language. We do, however, and while "three hundred and seventy times less," is easy to say, its hard to think about.

      More to the point the goal of language, especially in a technical setting, is to convey ideas in a the way most likely to be understood by the listener, not they way more convenient to say by the speaker, outside of a very few situations.

      --
      You're special forces then? That's great! I just love your olympics!
    22. Re:I hate it when; by Richy_T · · Score: 2

      I believe he would have completed the sentence with "capacitors". Current as in presently available, not Coulombs per second.

    23. Re:I hate it when; by Richy_T · · Score: 1

      Ten times is a multiplication, more is add, less is subtract.

      Ten times more is c+10*x

      Ten times less is c-10*x

      A tenth of is x/10

      A tenth less is x-x/10

      Nine tenths less is x-(9*x/10)

      So your saying that ten times less is the same as nine tenths less.

      Ain't nobody got time for that.

    24. Re:I hate it when; by socode · · Score: 1

      So? That book is not universally regarded by many grammarians (note the passive voice).

    25. Re:I hate it when; by thaylin · · Score: 1

      No, because "in greater quantity" still means additional, or above the amount.

      --
      When you cant win, ad hominem.
    26. Re:I hate it when; by thaylin · · Score: 1

      Because the meaning of more means additionally.. If you want number 2 you would say "I have x and want 10 times as many instead" You are losing 1 word in your wording, and significantly changing the meaning. In fact it begins to confuse people, because you are making words lose their meaning.

      --
      When you cant win, ad hominem.
    27. Re:I hate it when; by alva_edison · · Score: 1

      In this context more and less are not numbers, they are functions. Specifically times means multiplication, and more/less means that the base number (ten) has been taken to the 1 or -1 power.
      Also to say that anything has unambiguous logical meaning in a natural language is usually incorrect.

      --
      He effected a bored affect.
    28. Re:I hate it when; by bluefoxlucid · · Score: 2

      It's held in pretty high regard still. I've considering making some updates, but I can see much of the advice reflected in good writing (Wall Street Journal, Stephen R. Donaldson's writing, etc.) and ignored in bad writing.

    29. Re:I hate it when; by MightyYar · · Score: 1

      It probably is better style, but note that the phrase is a quotation in this case - so the writer is not the one at fault here. I can't even really fault the speaker too much, since he is trying to stick with a consistent comparison style ("one thousand times more", "ten times less"). Switching to tenths in speech might sound a little strange, or at least overly nerdy :)

      --
      W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
    30. Re:I hate it when; by MightyYar · · Score: 1

      In addition to it being completely unambiguous (unless you argue that caps can store negative energy), the line in question is not technical writing, but a verbatim quotation. The maligned author isn't even responsible for the sloppy terminology, the quoted speaker is.

      --
      W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
    31. Re:I hate it when; by Dcnjoe60 · · Score: 1

      That makes no sense.
      If you ask for 10x more of something you now have 11x, counting the original. But that does not change the fact that that 10x is 10 times more more than 1x. (For positive values of x).

      Nope. Consider x = 1. Would 1x be 1 times more than x?

      No, it's not. It's exactly the same amount. It's not any more at all, eg. it's 0x more.

      If you have 10 marbles and I have 2 times as many marbles, then I have 20 marbles. If I have 2 times more than you, I have 30 marbles (x +2x). As long as x is a positive integer, this is true (and quantities of zero or negatives don't make sense).

      So, If I had 1 times more marbles than you, than I would have two times as many marbles. For it to be the same amount, then I can't have more, I can only have 1 times as many as you.

    32. Re:I hate it when; by rjstanford · · Score: 1

      > In that example? "A quarter of a percent", by a long shot.
      So you're saying that "400 times less" is more complex than translating from two languages into "a quarter of a unit normalized to 100", then taking the reciprocal of one quarter and applying it to 100 to give 400?

      Yes, because people use phrases like "a quarter of a percent" all the f'n time, but have to stop and think about what "400 times less" means. Its the same way that I never use the "compact" form of time intervals like bi-weekly and semi-monthly because it takes an order of magnitude less processing power for most normal humans to understand the more lengthy "every two weeks" and "twice a month" phrases instead of figuring out what some rarely used expression means.

      --
      You're special forces then? That's great! I just love your olympics!
    33. Re:I hate it when; by rjstanford · · Score: 1

      As someone else pointed out, it's even MORE appropriate given what he said in the sentence: “Supercapacitors store ten times less energy than current lithium-ion batteries, but they can last a thousand times longer.". That's a good way to contrast 10 with 1000, and it's said eloquently, making perfect sense to probably 99.9% of the population.

      There are two problems with that theory. First, the storage capacity and the duration aren't actually comparable numbers. Second, if they were, you'd want to be comparing them at a factor of 10,000 - if the original sentence leads you to "contrast 10 with 1000," as you say then its poorly constructed. Contrasting "One tenth with one thousand," or "0.1 with 1,000" written numerically, would actually be the correct goal of the sentence.

      All of that ignores the fact that the storage capacity varies with size but the amount of time does not, so its even more ridiculous to try to compare those numbers in the first place.

      --
      You're special forces then? That's great! I just love your olympics!
  2. How would this get rid of power cords? by Lumpio- · · Score: 4, Insightful

    As far as I understand, in practice using a supercap isn't much different from using a battery. The energy density might be different but it's not like they magically create energy from thin air. They still need to be charged. Or are we talking energy densities that would last for the entire life of a device here?

    1. Re:How would this get rid of power cords? by Albanach · · Score: 4, Interesting

      My cell phone needs charged at night, but I don't consider it to be a wired phone and I don't find the charging cord to hinder me when making calls. My laptop, on the other hand, stays plugged in most of the time because it won't last a full day otherwise. It is hampered by the power supply.

      I think the idea here is that short term charging for devices is necessary, but normal operation would be wire free, thus they are liberated from wires.

    2. Re:How would this get rid of power cords? by rmdingler · · Score: 4, Informative
      The supercaps would be more like permanent batteries, and could be implemented in applications where retrieving a dead battery is inefficient.

      This is potentially groundbreaking. Current battery tech leaves a lot to be desired, the materials being used are finite, and it's possible there are no more great leaps in efficiency using chemicals to store energy.

      This is an entirely different way to store energy and the tech is in its infancy... storage capacities will likely improve with research.

      --
      Happiness in intelligent people is the rarest thing I know.

      Ernest Hemingway

    3. Re:How would this get rid of power cords? by CastrTroy · · Score: 5, Informative

      We are pretty much getting to this point without the help of super capacitors. With new batteries, solid state drives, and low power (not low speed) chips, it's possible to make a laptop last 20 hours. It's not mainstream, but give it another 2 or 3 years and it won't be uncommon that you'll only have to plug in you laptop at night, just like you do with your phone.

      --

      Anthropic principle: We see the universe the way it is because if it were different we would not be here to see it.
    4. Re:How would this get rid of power cords? by pushing-robot · · Score: 4, Insightful

      The summary (and the article, to an extent) is bad; this is a supercapacitor that also serves as a structural part, so all sorts of random things can be turned into (weak) batteries.

      They're envisioning a world where buildings, cars, and all sorts of things could be turned into giant capacitors, and you could just pump energy in somewhere and then draw it out wherever you like using some kind of short-range wireless transfer.

      The idea is a bit half-baked, but I support any science that makes our world more like Star Trek, even if it takes the form of mundane objects randomly exploding when there is a power surge.

      --
      How can I believe you when you tell me what I don't want to hear?
    5. Re:How would this get rid of power cords? by Charliemopps · · Score: 2

      Yea, but you still have to charge it. There's still a cord. The summary of both the article and the summary are basically an outright lie. The energy density is still less than that of a battery, and the tensile strength is ok... but not that great. Your device wont weigh any less, it just might be a bit smaller or have more room for other features because the battery is the case or components.

      A more honest headline would have been: "Electronic devices may soon be smaller and charge faster!"
      There's nothing in this technology that will eliminate the need for a cord.

    6. Re:How would this get rid of power cords? by dafradu · · Score: 1

      Don't take it literally, the power cords would still be there but since supercapacitors charge in minutes, not hours, you wouldn't have to stay connected all the time to recharge, thus "liberating" you from the power cord.

    7. Re:How would this get rid of power cords? by LordLimecat · · Score: 2

      The summary (and the article, to an extent) is bad

      In case you're on a browser thats removed the URL bar: This is slashdot.

    8. Re:How would this get rid of power cords? by Minwee · · Score: 1

      A more honest headline would have been: "Electronic devices may soon be smaller and charge faster!" There's nothing in this technology that will eliminate the need for a cord.

      Another equally honest headline would have been "Electronic devices may soon hold much more charge allowing them to be used without frequent charging via power cords or where existing battery powered devices would be impractical". The existing headline suggests the same thing with nineteen fewer words.

    9. Re:How would this get rid of power cords? by Nemyst · · Score: 1

      A building out of supercapacitors? I guess that could be interesting in a thunderstorm...

    10. Re:How would this get rid of power cords? by hubie · · Score: 1

      If they want to turn everything into big capacitors, I hope they work in ways to keep you from accidentally discharging it (years ago I took apart a cheap point-and-shoot camera and I touched the capacitor for the built-in flash and got quite a nice shock).

    11. Re:How would this get rid of power cords? by rjstanford · · Score: 1

      I still get 6-7 hours out of a 15" retina MBP used for development; add an extra 1/8" of thickness worth of battery and we'd be there now (although it wouldn't be as fun to carry around).

      --
      You're special forces then? That's great! I just love your olympics!
    12. Re:How would this get rid of power cords? by DarwinSurvivor · · Score: 1

      I wonder how many of these supercapacitors you could charge with a lightning strike.

    13. Re:How would this get rid of power cords? by Richy_T · · Score: 1

      Though replaceable batteries provide much the same benefit.

    14. Re:How would this get rid of power cords? by bemymonkey · · Score: 1

      What kind of a workload are you looking at on the go? For office/web/coding, there are many laptops already available that will last longer than your typical smartphone.

      I have a Thinkpad X220 (Sandy Bridge) that I unplug in the morning, use on battery all day (9 cell 94Wh) and then plug in when I get home, usually with 20-30% remaining after an active runtime of roughly 10 hours. A 13" MacBook Air should be able to improve on that time...

    15. Re:How would this get rid of power cords? by CrimsonAvenger · · Score: 1

      where buildings, cars, and all sorts of things could be turned into giant capacitors

      Having been shocked by a large cap back when I was fiddling around with discrete electronics back in the Dark Ages, the notion of being inside a building-sized cap thrills me so much that I think I'll be sick that day.

      Seriously, a building-sized cap failing spectacularly would not be a fun thing to be near.

      --

      "I do not agree with what you say, but I will defend to the death your right to say it"
    16. Re:How would this get rid of power cords? by unrtst · · Score: 2

      Another equally honest headline would have been "Electronic devices may soon hold much more charge allowing them to be used without frequent charging via power cords or where existing battery powered devices would be impractical". The existing headline suggests the same thing with nineteen fewer words.

      I don't buy it. Take a cell phone for example... the existing lion batteries have more mass than the phone chassis, and they have 10 times the energy density of the supercap in question. Just for the sake of argument, let's say the phone chassis has twice the mass of the existing battery, and lets say you replace both the battery and the phone chassis with this supercap material. You would end up with 3/10ths the energy capacity.

      AFAICT, this tech does nothing to eliminate power cords. Even in their example of a house with supercap in place of drywall (I'm sure that's more cost effective than running wires /sarcasm), devices would still need to connect to the supercap, which will almost certainly be facilitated by plugs placed regularly along the wall.

      IMO, where this tech is interesting is in applications where you would not normally find an electronic device, but a low powered device may be desirable. For example, if you could make a bicycle frame out of it and have a similar strength to weight ratio as existing frames, then electric assist on a bike would not require lugging a heavy battery around with you. It'd also alow for much faster charging (ex. so delivery people on bikes, which is very common in NYC and other big cities, would always have power for their next trip).

      I'm sure there are many other uses, but those where capacity is already the major issue are probably not where we should be looking first. In all cases though, this does not eliminate the cord. Charges faster, sure... and has one tenth the capacity, so you'll be charging more or lugging more weight around.

    17. Re:How would this get rid of power cords? by bluefoxlucid · · Score: 1

      That explains Star Trek objects exploding all the time.

    18. Re:How would this get rid of power cords? by drinkypoo · · Score: 1

      That explains Star Trek objects exploding all the time.

      Probably nothing will ever actually successfully explain why so much stuff on the bridge explodes all the time. The bridge should be isolated from the rest of the ship, with some kind of extremely nonconductive isolation technology used if necessary, plastic pushrods or whatever.

      --
      "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
    19. Re: How would this get rid of power cords? by rjstanford · · Score: 1

      Actually its not - a reasonably high capacity car like the Model S has no significant issues with charge time. A ridiculously small number of people drive over 250 miles in a day, the notion that not supporting them directly is a "major hurdle" is just plain incorrect. The number of people who drive over 250 miles a day who can't take 20 minutes or so every few hours to top up at a Supercharger station is even smaller, but we're already well into statistical insignificance at this point.

      Its akin to claiming that since some people need to tow horse trailers, the small towing capacity of every modern mid-sized sedan is a "significant hurdle" that will prevent their adoption.

      --
      You're special forces then? That's great! I just love your olympics!
  3. "not limited by plugs and external power sources" by Gaygirlie · · Score: 2, Insightful

    Bullshit. Where exactly do they plan to get the power to charge those supercaps? From thin air?

  4. Re:"not limited by plugs and external power source by rmdingler · · Score: 1
    TFS is misleading.

    One of the great advantages of this new tech is the super capacitor can be charged and discharged for millions of cycles, versus thousands of cycles for existing battery technology.

    --
    Happiness in intelligent people is the rarest thing I know.

    Ernest Hemingway

  5. Re:"not limited by plugs and external power source by cjb-nc · · Score: 5, Informative

    The other advantage is the speed at which you can charge a capacitor compared to a battery. I have a consumer cordless screwdriver with a capacitor in place of a battery. It runs for a decent time and runs down, like most such devices. Unlike a battery, it recharges to full in 90 seconds, not hours.

  6. How many? by jamesl · · Score: 4, Funny

    How many stories have we read in the last two decades about breakthroughs in power that will replace current battery technology, cut the power cord, end our dependence on carbon or make our undies clean and white on half the water? How many have resulted in actual products and a better life?

    Only the clean and white one.

    1. Re:How many? by captjc · · Score: 1

      I remember watching the Computer Chronicles from the late 80's, early 90's about the new Laptops being released that feature a rechargeable battery with whopping 1.5 hours battery life! Cut to today, I only need to recharge my iPad twice a week, My 7 year old Macbook gets 3-4 hours (though, I did replace the battery not too long ago), My phone can last a week or two without a recharge. Sure, some of that was due to miniaturization and more efficient components but battery technology has vastly improved in just the last 20 years alone. We've gone from huge Lead Acid bricks to small Lithium Ion power packs.

      I can't wait for batteries and charge cables to be replaced by Supercaps and induction charging on mainstream devices.

      --
      Slow Down Cowboy! It's been 1 hour, 47 minutes since you last successfully posted a comment
  7. Re:external power sources? by rossdee · · Score: 1

    1 milligram of antimatter could power a cellphone for a couple of thousand years or so.

  8. hold a charge when it takes a lickin' by Threni · · Score: 3, Funny

    What does this folksy nonsense actually mean? Something to do with saliva?

    Yep, reckon so..gahoop gahoop gahoop.

    1. Re:hold a charge when it takes a lickin' by RatherBeAnonymous · · Score: 1

      Have you ever tested a 9-colt with your tongue? I wouldn't try that with a similarly sized super capacitor. You are liable to bite your tongue off.

    2. Re:hold a charge when it takes a lickin' by fahrbot-bot · · Score: 1

      Have you ever tested a 9-colt with your tongue? I wouldn't try that with a similarly sized super capacitor. You are liable to bite your tongue off.

      ...or the antimatter "rossdee" mentioned previously:

      1 milligram of antimatter could power a cellphone for a couple of thousand years or so.

      --
      It must have been something you assimilated. . . .
  9. Re:"not limited by plugs and external power source by Idarubicin · · Score: 5, Insightful

    TFS is misleading.

    One of the great advantages of this new tech is the super capacitor can be charged and discharged for millions of cycles, versus thousands of cycles for existing battery technology.

    Actually, that's not really the point of the article, either. Large numbers of charge-discharge cycles are a feature of pretty much any supercapacitor, not just these ones. They're arguing that these new supercapacitors have sufficient mechanical strength and robustness that that could be used as structural, load-bearing components in some applications. In other words, you don't have to put a box around them; they can be an integral part of the frame or case of your device. The battery (or capacitor) doesn't have to be a separate, discrete, armored lump inside the case.

    In practice, as long as the energy storage density of these things is still just a tenth that of rechargeable lithium ion batteries, they're going to have problems in mobile applications. Near-indestructible material and near-instantaneous charging are both good things. But I'm not really "liberated from my power cord" if I have to top up the capacitor every couple of hours, or if my new battery-less iPhone weighs a couple of pounds with its giant supercapacitor frame.

    --
    ~Idarubicin
  10. Re:"not limited by plugs and external power source by Megane · · Score: 1

    Supercaps also charge a lot faster, because they don't have to convert the charge to a chemical change like a battery. But they are also very touchy devices, and you especially don't want to go over their voltage rating. It's the same reason you want to specify double the voltage rating for electrolytic caps.

    --
    #naabhaprzrag, #sverubfr-000, #agi-fcbafberq, negvpyr[pynff*=' negvpyr-ary-'] { qvfcynl: abar !vzcbegnag; }
  11. Re:external power sources? by Megane · · Score: 1

    But don't you know that TELSA wanted to give us all FREE ELECTRICITY until the OIL CARTEL had him silenced? It's all a conspiracy!

    --
    #naabhaprzrag, #sverubfr-000, #agi-fcbafberq, negvpyr[pynff*=' negvpyr-ary-'] { qvfcynl: abar !vzcbegnag; }
  12. Correction by Richy_T · · Score: 1

    x+10*x and x-10*x in the first two formulas.

    And "you're", not your. Ouch.

  13. Eh? by FatLittleMonkey · · Score: 4, Insightful

    Batteries have gone through multiple generations of technology in the last two decades. Solar panels are now so cheap that the physical installation costs are the biggest part of installed costs. Solid-state storage is increasingly the norm. OLEDs are now in TVs, 77" diag. 4k-ish, WRGB. e-Paper readers cost tens of dollars and are seen as outdated tech. Smartphones cost tens of dollars. 4G phones. Gb/s Wi-Fi. Etc etc.

    How much fucking progress do you need?

    (When Li-Ion was introduced in '91, it stored less than 90 Wh/kg, now it's over 200 Wh/kg. The price was over $3/Wh, and is now less than 30c/Wh. http://www.batteryuniversity.com/images/parttwo-55h.gif. And there's no reason to suspect it will stop, we're still pushing Li-polymer capacity. With LiS, LiMetal, and ZnAir all in the early commercialisation stage, and graphite-everything in the lab stage.)

    ((Solar panels have doubled in capacity/m^2 every ten years, and halved in price/m^2. Every doubling of global production cuts the price by 1/5th. http://www.economist.com/blogs/graphicdetail/2012/12/daily-chart-19. And there's no reason to suggest the trend will stop.))

    --
    Science is all about firing a drunk pig out of a cannon just to see what happens.
  14. Nothing to do with "Liberating form Power cords" by Quantus347 · · Score: 2

    This "new" supercapacitor has nothing to do with liberating devices from Power Cords. Supercapacitors still need to be externally charged. All this development does is make them a bit more resilient than current model when in more rugged environment, and supposedly make it where we used supercapacitors as structural components. In other words your car would not have a separate battery to replace, because it's frame itself would be used to store electricity. While the creator seems to think that is the wave of the future, I dont see it as a particular good (or cost effective) idea.

    --
    Common Sense isn't as Common as people think...
  15. instant charge. Touch, not plug in by raymorris · · Score: 1

    Capacitors charge virtually instantly, so a device wouldn't have a power cord attached to it for hours. Instead, you'd just touch it to the charger.

  16. bestiality is illegal and guns are not for oral us by raymorris · · Score: 3, Funny

    > a 9-colt with your tongue?

    If that's a 9mm Colt, that sure sounds like a bad idea.
    If you're talking about tonguing a horse - nasty.

  17. Re:"not limited by plugs and external power source by Tyler+Durden · · Score: 1

    "In this house we obey the laws of thermodynamics!"

    -Homer Simpson

    --
    Happy people make bad consumers.
  18. Re:"not limited by plugs and external power source by asylumx · · Score: 1

    I have a consumer cordless screwdriver with a capacitor in place of a battery. It runs for a decent time and runs down, like most such devices. Unlike a battery, it recharges to full in 90 seconds, not hours.

    Link please? That sounds like something worth buying...

  19. Re:"not limited by plugs and external power source by bluefoxlucid · · Score: 2

    Electrolytic voltage ratings are somewhat meaningless. They specify one of infinite meaningful measurements for the same thing.

    A 50V capacitor isn't just 50V; it's 50V rated for some operating hours. Let's say 10,000 hours. If your capacitor oscillates across 50V (say a GND+150VDC on one side and GND+100-150VAC on the other, or just 50VAC), you can run that capacitor for 10,000 hours. If we drop that voltage to 25V, it'll run 20,000 hours. Raise it to 100V, it'll run 5,000 hours.

    Essentially, its useful life scales linearly with voltage. This cap has 500,000 / E hours of life for an AC voltage of E.

  20. Or we could just use USB3 instead by WillAffleckUW · · Score: 1

    A far simpler idea is just to use USB3 instead, with bidirectional power flow.

    There, simpler, only one plug, no muss no fuss.

    Your PS4 and xBoxOne and HDTV will still suck up as much power on standby as they do when "on", mind you.

    There's your power vampire.

    --
    -- Tigger warning: This post may contain tiggers! --
    1. Re:Or we could just use USB3 instead by drinkypoo · · Score: 1

      Your PS4 and xBoxOne and HDTV will still suck up as much power on standby as they do when "on", mind you.

      Will they? I would have imagined that the CPU in the PS4 and Xbone could shut down individual cores and perhaps even functional units when unused.

      --
      "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
  21. Re:"not limited by plugs and external power source by asylumx · · Score: 1

    Ya, so that's an article about a prototype but what I asked for was a link to the consumer product that the other post was referring to. Great job being a dick and still not getting the point.

    https://www.google.com/search?... -- nothing.
    https://www.google.com/search?... -- nothing.