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Ultracapacitors Soon to Replace Many Batteries?
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."
HEY!
I want my friggin 15 hour battery life laptop first! You promised!
...your fingers may become part of the capacitor.
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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.
Perhaps they can use this technology to make more lethal tasers. Or at least tasers that give some good burns.
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?
The theory of relativity doesn't work right in Arkansas.
I believe it depends on the type of rechargeable. The nickel cadmium did. Lithium does not.
The problem I've had with all of them is their life span. After a year of regular use, they then to hold a fraction of their original charge. It appears ultracapacitors have a much longer life span. rock on
What gave you that idea? Nickel-cadmium batteries are obviously afflicted. What is a common misconception is that Nickel metal hydride batteries are also affected.
File under 'M' for 'Manic ranting'
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.
Gone!
NiMH can be screwed up by overcharging, with the end result exactly the same as the memory effect for NiCD: their capacity greatly reduced. This is my first-hand experience, not hearsay. You need fairly sophisticated charger for NiMH, the one that protects from overcharging. Mine didn't.
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.
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.
Microsoft taketh away.
Deleted
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!
... yes, if you could build a capacitor that would survive a direct lightning strike...
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 systems.
The "supercaps" are designed on similar principles to batteries but with a very different physical design strategy. Capacitors are built like a roll of paper towel, and have a very large surface area of contact between the plates. (several square feet for a small capacitor in a computer) This allows them to very rapidly charge and discharge because the current is distrpbuted over a large surface area. They store their energy as an electrical charge, and as you draw from it, the "pressure" lowers in relation to how much energy you have removed.
Lead acid and other chemical batteries store their energy as a changed chemical state. The chemicals build and maintain a fixed charge on the plates. This allows a 12 volt battery to hold 12 volts until it is almost discharged, unlike capacitors whose voltage drops as they are discharged. It could be quite a challenge to deal with this change in basic operation. Capacitors have another advantage in that they are able to directly produce a very high voltage, limited only by the quality of the insulating materials they are made with. Capacitors can easily hold hundreds of volts, and there are industrial caps that can hold many thousands of volts.
There's an interesting similarity for those of you familiar with paintball. Capacitors behave almost exactly like high pressure nitrogen tanks - they have very high energy and can have a very high capacity, their "pressure" drops during use, and a regulator is required to output the correct pressure. (voltage) "CA" tanks (Constant Air, CO2) on the other hand rely not on high pressure, but on a supply of liquid CO2 in the tank which changes state as gas is drawn from it, boiling to return the tank to the preset pressure. (voltage) When the supply of liquid CO2 is used, it falls just like a dead battery.
Traditional paintball guns can run on a nitrogen tank if they are equipped with a regulator to knock the pressure down to a level the gun can handle. In the same way, electrically a cap could replace a battery with not a lot of modification, but the design is very different.
Paintball air tanks are roughly the same by volume, but a modern high capacity nitrogen tank can provide more shots than a high capacity CA tank. CA tank capacity is limited by its physical size - like nitro, the more liquid (gas for nitro) you can fit into it the higher the capacity. Nitro tanks have the added advantage of the max pressure the tank can take. Stronger tanks can hold more pressure for the same size, so increases in technology allow for a greater power density in Nitro but not in CA.
I expect the same should be true of caps vs batteries - you can only put so much electrolyte in a battery. You can look for better electrolytes, but you eventually run out of better solutions. Capacitors are limited by their electrolyte and the quality of the insulators. (a bit like the ability to hold pressure in a nitro tank) Assuming technology can continue to improve on that front, capacitors may catch up with or surpass traditional batteries in power density.
I'm not counting on it though. Although capacitor technology is far from reaching its pinacale, most of the major breakthroughs have already been made. The advent of carbon fiber made Nitro tanks the better deal. Unless a new technology of the same magnitude comes up for capacitors, I don't think we'll see them in our laptops anytime soon. There's also a safety factor when you are trying to push any form of pressure really high. Nitro tanks are downright dangerous if mishandled, and must be treated carefully under the best of conditions. Jacking up the voltate on your laptop's supercap to 100kv... even if it becomes practical, I don't know if I want to carry THAT around.
I work for the Department of Redundancy Department.
I believe that has been debunked as an urban legend. Read more here: http://www.dansdata.com/gz011.htm
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.
Sure, that is a large current. The best way to charge an ultra capacitor is from another larger ultra-capacitor, which is charged slowly.
Excuse me, but please get off my Pennisetum Clandestinum, eh!
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?
Michael
Beware of Sales Reps bearing gifts.
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.
...you read that title as "Utahraptors soon to replace many batteries"
What sound do people on rollercoasters make? Hint: it's not Xbox 360.
Does being on slashdot mean that you must be rude?
:)
You must be new here... idiot.
Random and weird software I've written.
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.
even if these caps only hold a charge for 1 hour, they will recharge in a few seconds and will be 5 time lighter then batteries. are you really so dense as to be unable to see applications for a lighter faster charging power source?
If you mod me down, I will become more powerful than you can imagine....
Hmmm, that's an expensive myth for professional cabinet makers, carpenters and other trades that use cordless screwguns on a daily basis. I personally go through an pair of 18v batteries every 6 months, even with tricks like blowing a fan across the charging battery to air cool it. Of course on a busy day I will run each battery through two charge cycles.
We are all just people.
Only if it's of the 'flux' variety. Of course, you'd have to have the timing perfect to hit the wire, just as the strike hits the clocktower, and you hit 88MPH.
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).
I assume it would take a series of such impacts though to fully deplete a charge. *shrug* But it might be something worth taking into consideration.
Or make a handy exploit... just get the guy riding in the car behind you to bump you a few times and he's out of 'gas'. Or as another prank, find a way to fully discharge the capacitor of a stationary car in a few seconds, rendering it underivable without a booster charge.
As far as I'm concerned, if the battery loses the ability to store the same amount of power as it did when you first bought it, then it has a problem with battery memory. I don't care if it's not the same thing as the old battery memory thing with the Ni-Cads, it's still a huge problem. I have an 2 year old cell phone that doesn't hold a charge at all and it has a lithium battery. If ultracapacitors solve this problem, along with the problem of depleting charge even when the device is not in use, then it will be a great step for portable electricity.
Anthropic principle: We see the universe the way it is because if it were different we would not be here to see it.
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.
Plastic film capacitors will wear out if they are operated at excessive currents.
High-k ceramic capacitors degrade partially over time.
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a. You are climbing up and down ladders all day and don't want to trip over power cords
b. You work in a space with limited or no continuous power supply
c. You have 2 or 3 fully charged batteries and a quick charger
d. Not all tools work with compressed air
e. You kept slamming the cord to your old tool in the tailgate of your F350.
f. all of the above and a lot more.
Memory is a very specific occurrence in very specific conditions with a very specific type of cell (sintered plane nickel-cadmium). It exists. You've never seen it.
>>I have an 2 year old cell phone that doesn't hold a charge at all and it has a lithium battery.
It's not memory. It's worn out (too many cycles) or reached the end of its calendar life (since manufacturing, not since you bought it - newer-generation LiIon cells are much better at this aspect). Or both. All cells do this eventually. 2-3 years for a consumer grade cell is not at all unusual. Yes, there are exceptions; I own a few of them.
Capacitors have a lifespan of "functionally forever." You're right: perfected, they'll be a whole lot better than any type of cell we have now.
R
Yeah and like you said you aren't a professional. I am and I swear by them. I'm still hoping that a company will come out with an electric 18 gauge stapler so I can stop dragging around an air hose.
If you only use them occasionally then you can't beat corded because the battery will always be dead when you need it.
Memory is a very specific occurrence in very specific conditions with a very specific type of cell (sintered plane nickel-cadmium). It exists. You've never seen it.
The above is spot on.
Another common cause of what is incorrectly thought to be "memory" is the corollary myth that you MUST deplete NiCd batteries completely before charging. While a full discharge can, in fact, sometimes be useful for certain types of cells, this is generally untrue for real-world batteries (comprised of multiple cells). A battery with several cells in series will always have slightly unbalanced cells, and the weaker cells will lose charge first. As the weakest cell begins to collapse, its neighbors in the string will crush it to zero volts, and then to a negative (reverse) voltage. To permanently damage a cell more effectively, you'd really have to apply yourself.
ALWAYS stop using the battery at the first sign of depletion -- continuing to use it will just kill one or more of its cells.
- Pull battery apart.
- Melt down the pieces.
- Refurbish the electrodes and solute.
- Rebuild the battery.
You can get the battery back to its original state. Otherwise, electrodes will always be built incorrectly [they become more and more 'fuzzy'] and performance will deteriorate.The end result is that while it is possible to remove a sufficient amount of entropy from the system, it is not always easy, as in, easy enough to do on a regular basis. It is not a memory problem, it is an aging problem: as the act of recharging introduces entropy itself, and recharging happens within the battery, that is where the entropy goes.
We at slashdot are scientists, specialists and kernel hackers. Your FUD will be found out.
As far as I'm concerned, if the battery loses the ability to store the same amount of power as it did when you first bought it, then it has a problem with battery memory
Battery memory is a specific problem with specific preventative measures and fixes. Would you call a lead acid battery's tendency to sulfate if left uncharged(or deeply discharged) memory? While it does lead to lower capacity and shortened life, it's not the same thing as NiCad memory.
From my understanding, LiIon tech currently degrades with age - it doesn't matter how often the battery is charged*, it's charge state or anything. It's pure degradation over time - it could be sitting in a controlled climate warehouse and it'd still be substantially worse after only a year or three. And it's permanently lost - so I'd hardly call it a memory issue. At least with memory problems you can more or less fix the batteries without reprocessing them.
*though this still wears the battery out.
I don't read AC A human right
You are describing electrolytic rather than ultra (or super-) capacitors.
These are designed on a very different principle. Rather than using rolled up etched/oxidized aluminum foil (the oxide acts as the insulator), these use activated carbon electrodes and an ion-permiable membrane as the insulator. This creates a capacitor with a much larger surface area than a traditional electrostatic or electrolytic capacitor.
At any rate, that is the *current* generation (up to 2700 farad capacitance-- which is huge-- those capacitors they warn you about in the PC power supply are less than a farad). It looks like the use of nanotubes may allow for *far* more powerful capacitors.capable of delivering workloads sufficient to replace batteries in many applications.
Actually the current generations of ultracaps are already replacing batteries in electric vehicles and hybrid fuel cell vehicles, and a wide range of other applications. Especially in hybrid fuel cell vehicles, the reports at the moment indicate that they lead to better fuel economy than a traditional battery for storing eneregy from regenerative breaking, etc.
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"Just every time you charge it, you induce more entropy in the universe."
Is it wrong that this seems vaguely threatening to me? While I know everything we do either has no effect or introduces more entropy into the universe, something about "every time you charge your phone you bring the entire universe closer to its death" is just a turn-off.
Also, this is suddenly my favorite vague defamation statement... "X lives an entropy-positive lifestyle, and every day brings us closer to the end of the entire universe!"
Just in case anyone is interested in learning more detailed information about the development process, the leader of the lab at MIT that the linked article described just gave a speech at Dartmouth's Thayer School of Engineering. The speech is publicly available either as podcast or video, the latter half of which deals specifically with carbon nanotube ultracapacitor creation.
even with tricks like blowing a fan across the charging battery to air cool it
Some primitive recharagable Ni-cad/ni-mh battery chargers look for an increase in battery temperature to know when to stop charging.
There is a fine point where a battery stops charging and starts cooking. This is sometimes measured either by temperature or by looking a subtle changes in way the charging current varies over time. Other chargers are more stupid and either always charge or charge for a fixed amount of time.
Li-ion batteries are much more delicate and require more complex rechargers...
While Li-Ion/Li-Polymer batteries don't have "memory", as per se, they do have load cycles with highly uneven wear. The more you discharge the battery, the more you wear your battery down per ampere used. Discharging from 33% full to zero (in reality when the protection circuitry cuts in) a single time cuts down your battery life more than discharging from full to 66% five times over.
This is the main reason why it's recommended that you charge Li-Ion batteries as often as possible, and even "top them off" when used regularly[1]. If you use a quarter of a charge per day, your battery will last much longer if you charge it daily or every other day than if you charge it every three or four days, even though the "cycles" used are the same.
I recommend keeping anything below 1/3 full for "emergency use" -- there when you really need it, but avoided otherwise.
If you frequently use a laptop (or cell phone) until it runs out of power, or even gets very low, it's better to go with a NiCd or other battery, cause Li-Ions will have a seriously short life span if used that way.
[1]: If a Li-Ion/Li-Polymer battery is stored, half charged is better -- the self-discharge and chemical damage done from this is lowest at around 40% charge, which due to the protection circuitry equates to about 50% on the meter.
That's why you have a household capacitor bank that sips juice from the grid, then discharges quickly for just these sort of applications.
- They have limited charge/discharge cycles to begin with
- Quick-charging batteries (e.g., at a rate faster than C/10) dramatically shortens the lifespan of the cells, regardless of whether they claim they're designed for quick-charging
- Rapidly discharging the cells (as in high discharge-rate applications like a screwgun) also causes heating, which shortens the lifespan
- Commencing a recharge cycle before the depleted cells have had a chance to cool after a high-rate discharge cycle is also very hard on them, further shortening their lifespan
Unfortunately that's just the way it goes with the application you're using them in; you have to keep working during the day, and that means keeping your screwgun supplied with current, which means quick turn-around on your battery packs. Ultracaps don't have a fraction of the capacity per cubic centimeter versus basically any rechargable battery technology, even if the huge ones that (for instance) Maxwell makes for things like subway cars and streetcars do have an incredibly low equivalent series resistance (and therefore capable of tremendous charge/discharge rates). Compare that to the energy storage density of Li+; we're talking roughly 29 times the density with currently-available COTS technology. I have every confidence that if enough research money is invested in developing the technology they can reach the aforementioned 50%, but they've got a long way to go to get there.The GP mentioned equipment like phones and PDAs, which typically have a battery of about 700 mAh at 3.7 V = 9000 Ws. Household wiring in Europe can usually do 16 amps at 230 V = 3680 W. With a factor 2 for conversion losses and power factor it means you could recharge the battery in 5 seconds or so. The biggest problem is that you need some kind of switched power supply with 10 times more capacity than that in a desktop pc, so that would be a pretty big and expensive battery charger.
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1. What the blueprints say, and what people will do to their ultra-capacitor-powered car are two different things. The Darwin Awards are full of people who... did things quite differently than the manufacturer imagined.
So I'll bet someone _will_ take it as necessary proof of manhood to take it apart, cut the cables, and make a dangerous mess, just because, you know, his dad told him that Real Men mess with their car's engine. And if he doesn't take it apart and make a bigger mess (before finally taking it to the mechanic anyway), then he might as well wear a dress and a purse.
2. And that's not even counting the millions of clueless rice boys (car modders) and the unscrupulous vendors preying on them. Someone _will_ sell clueless insecure guys a special power cable claimed to increase their horsepower by 10%, or something equally ridiculous. (Same as the 1000$ hi-fi power cables sold to "audiophiles," or 4" exhaust pipes for 1.1 litre engines. Odin knows there's no shortage of buyers for either.) Watch them take the engine apart and do dangerously irresponsible things with the cables.
Or, honestly, it just begs doing dangerous stuff with the voltage at either the capacitor (to increase range), or the electro-motor (since torque and horsepower do increase with voltage.) When some insecure kid's bragging rights depend on how fast he can accelerate, do you honestly think it won't happen? I can see the whole overclocking willy-waving contest happening all over again with cars.
And as with chips, there'll be a bit of variation to how much you can push a part. The fact that there's always a safety margin doesn't mean it's _guaranteed_ to go X% higher. The safety margin is there precisely because you get a bit of a gauss curve, and some parts will fall a bit short. Some motors will cheerfully take twice the voltage, some will have a spot of thinner wire or insulation and short out. Some capacitors will cheerfully take more voltage, some will have a weaker bit of insulation somewhere between those plates, and get an arc right through it if you push them.
Except with overclocking, at most you fry the chip, and tend to see it crashes long before that. With a capacitor you just get a hell of a lot of energy discharged in a very short time. Assuming that the capacitor only holds the energy of, say, half a tank of gasoline, discharging all that energy in half a second is very much equivalent to half a tank of gasoline blowing up. Better yet, stored energy rises with the square of the voltage, so over-volters will get quite the fireworks.
3. Well, what the blueprints say, and what the whole thing looks like after crashing into a tree, are often different things. I'm sure, for example, in normal cars radiator blueprints don't involve it having several breaks and punctures either.
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