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Charge Your Cellphone In 20 Seconds (Eventually)
New submitter GoJays writes "An 18-year-old from Saratoga, California has won an international science fair for creating an energy storage device that can be fully juiced in 20 to 30 seconds. The fast-charging device is a so-called supercapacitor, a gizmo that can pack a lot of energy into a tiny space, charges quickly and holds its charge for a long time. What's more, it can last for 10,000 charge-recharge cycles, compared with 1,000 cycles for conventional rechargeable batteries, according to the inventor Eesha Khare." This one in particular has been used so far only to power an LED, rather than a phone or laptop, but I hope in a few years near-instant charging of portable electronics will be the norm as supercapacitors grow more common.
Very Cool
"It is also flexible, so it can be used in rollup displays and clothing and fabric,"
The one thing I like about supercapacitors (and non-super capacitors) is how quickly they can release all their energy. I can't wait to hold one up to my ear when it's embedded inside a device whose manufacture was outsourced to the lowest bidder!
did she have some new angle to the tech?
you can buy capacitor based battery replacements for cars.
world was created 5 seconds before this post as it is.
Sometimes I really hate "technology" reporting.
Somebody buy the poor girl a Nokia phone, the newer ones run for a month between charges.
My phone battery has a capacity of 2.1Ah. To charge it in 20 seconds would require a current of 380 Amps. What kind of charger could safely supply that?
With the rapid adoption of portable electronics, Eesha Khare, 18, of Saratoga, California, recognized the crucial need for energy-efficient storage devices. She developed a tiny device that fits inside cell phone batteries, allowing them to fully charge within 20-30 seconds. Eesha’s invention also has potential applications for car batteries.
Will be doing some more Googling, but seriously, a link to the lab in which she worked or article/abstract published would be nice. Surely these are gifted kids, but I can't help but think the reporter really doesn't understand what she's done to write any thing more than a press release.
The only possible interpretation of any research whatever in the 'social sciences' is: some do, some don't
...change the battery with a freshly charged one (if you're not a lucky iPhone owner).
Slashdot, fix the reply notifications... You won't get away with it...
Is there a link to some article not in the mainstream media? The article has no details at all. Did she use an off-the-shelf super capacitor? What circuits did she make (one characteristic of a capacitor is the voltage immediately goes down as soon as you take charge from it, unlike a Li-Ion battery which maintains a more or less constant voltage through most of its charge), and how efficient is the voltage regulation? What about the energy density of the device? All supercaps I know of have a very small fraction of the energy density of a lithium ion battery. To replace a Li-Ion you need similar energy density or you get a massive phone.
Oolite: Elite-like game. For Mac, Linux and Windows
What a lot of these articles forget is the current requirements to charge something fast. Just because something can be charged fast doesn't mean you can do it.
Let's take a typical laptop battery of 70 watt hours. To charge it in one hour, you need a 70W power supply (more or less). Now let's charge that same battery - if we can - in 30 seconds, or 120th of the time. You'll need an 8.4kW charger to do that, which is going to be much larger and heavier than the laptop. In Britain where the mains electricity is 240 volts, you're going to need 35 amps to do that (typical household circuit is 13 amps, high power circuits for example ovens and tumble dryers are 30A). In the United States you'll need 70 amps.
OK, so you can charge slower (but still much faster than a conventional battery) but it's still going to require a large (heavy) power supply for your laptop if you want to make the charging speed significantly faster than current lithium ion batteries. You're either going to wind up lugging around a lot of extra weight with your portable machine, or you're going to need two chargers (more expense). The thing is, the times when you really wish you can charge a battery quickly are always times you're travelling and so won't have the large heavy charger with you!
Oolite: Elite-like game. For Mac, Linux and Windows
"supercapacitor, a gizmo that can pack a lot of energy into a tiny space, charges quickly and holds its charge for a long time"
Ah, Not really, no. Supercapacitor=1Mj/KG, pretty weak sauce relatively speaking.
Personally, I'm, holding out for a 'Doug Stanhope' phone with an ethanol fuel cell than 'runs on booze'.
"I bless every day that I continue to live, for every day is pure profit."
The rough version is there, it's called (quite missleadingly) a second battery plus a charger that can charge batteries externally. Been using that setup for years now and it can charge a phone in seconds, as long the phone has a changeable battery.
Guess companies might be able to fine tune it, e.g. make batteries easier to eject and insert, plus add a capacitor (a normal one, that keeps the phone live for say 30s), and you've got instant charging, today.
A 20 second loading of cellphones is not really a must have. It is a nice to have. With a phone you will be for longer then 20 seconds to reload it (e.g. at your desk, when you sleep)
Where such load times would come in handy is with electronic cars. That way you can drive cross country and do refills at the same speed as you do now.
Don't fight for your country, if your country does not fight for you.
I am surprised nobody has been locked away for providing a minor (I presume she did some work before turning 18) with access to chemicals and/or processors. If you crank out this sort of shit at eighteen, you had some seriously supportive tutors who decided not to follow every rule of the book.
Ten minutes to charge and off the shelf:
http://www.toshiba.com/ind/product_display.jsp?id1=821
* Carthago Delenda Est *
the idea of moving large amounts of energy between two storage reservoirs is inherently more dangerous than the slow charge systems we use now.
by the way the name FUD got a lot of popularity regarding Java.
fear - im afraid java will be bought by some shit hole corpoarte master --- true
uncertainty - im uncertain if sun will even be a company in a few years. -- true
doubt -- i dbout anyone will want to deal with version incompatabilities and all the other junk to use java on web pages, especially when javascript and webgl are doing so well -- true
how dare you. HOW DARE
was ruining about 20 pairs of bedsheets with cum stains, and finishing X-Wing vs Tie Fighter
powering our cell phones is that in order to get the super high capacitance the "plates" of the capacitor must be microscopically close together which limits the voltage at which they can operate to typically 2.5V. The next problem is that you can't use all the energy stored because you need a DC input converter circuit to regulate (and step up) the ever falling voltage as the capacitor discharges and those circuits require some minimal level of input, maybe a few hundred millivolts, below which they cease to function. While the total energy storage capacity of the capacitor is great, you can't use all of it, so if you compare the usable energy storage of a supercapacitor to a similar sized Li-Ion battery, the battery wins.
Batteries, on the other hand, provide adequate current via a chemical reaction that maintains a more or less constant, higher voltage output until the battery is almost completely discharged, at which point the voltage drops precipitously. This works well with the circuits in a cell phone.
If this student managed to make a supercapacitor that operates at 5V or higher in the same physical volume as current technolofy 2.5V parts, or solved some other problem related to the technology- maybe a voltage converter circuit that efficiently delivers a usable current from the capacitor at 20 mV input, then she made quite a breakthrough.
I think fuel cells are a more promising technology for cell phone battery replacement than supercapacitors. You can have your "instant" charge by squirting in some butane or whatever fuel it uses, but then I'm not sure if they can pack the same energy density as li-ion cells. The other potential game changer for phones, computers, and cars is lithium-air batteries which have much higher energy densities that li-ion cells.
Just have two batteries. On on charge and one in the phone. It will also take 20 seconds to change the battery.
"We mustn't be caught by surprise by our own advancing technology" -- Aldous Huxley
So how is it that an eighteen year old girl with no science degree comes up with what PHDed scientist have been looking for for decades? Foot dragging to prevent the federal grants from disappearing after the invention? Or incompetence maybe? The curse of embracing the God hating theory of evolution? We might need to turn to our high school students for answers from now on. It would certainly be cheaper.
One problem with capacitors is the charge is stored a lot like water in a tank. As you use water the water level drops, in any capacitor, as you use it the voltage drops.
The governing equation is Q = 0.5 *C*V*V.
A single cell (in a battery of cells) is composed of two materials of different chemical states and they produce a constant voltage until one of the chemical states is depleted. Charging reverses this, again at a constant voltage. The charge and discharge voltages in a theoretically perfect cell are ~~ the same, in a real cell, resistance caused voltage drops and departures from irreversibility lead to differences in the charge discharge voltage. You must charge with a high voltage than you get on discharge.
A second problem, is the fact that a bulk material changes state in a cell, this inherently stores more charge than a capacitor, which is a surface layer of added charge. It is true that since the capacitor involves no change of state, that the life is more or less infinite, and because it is a monolayer of charge, you can charge and discharge at speeds limited only by the current limits of the wires.
The net result is the energy density of the best capacitors is barely as good as the worst batteries.
Battery graphs here http://tinyurl.com/autjb7l
Capacitor graphs here http://tinyurl.com/byqbdje
Direct comparisons here http://tinyurl.com/b9zwcdw
As long as you design a downstream voltage regulator to use the declining voltage to power your circuit at its required constant voltage, then ultracaps will find a niche in many pieces of equipment from Cars(as a peak acceleration source) to tiny items as the sole power
Interesting numbers. Just to compare, here's the energy densities of lithium-polymer batteries and super-capacitors, taking the values for best easily-available components I could find.
LiPo: 168 W.h/kg, 370 W.h/l
Super-cap: 5.1 W.h/kg, 6.6 W.h/l (I'm being slightly generous to the capacitor here, by counting the energy to discharge it to zero volts. In practice that last bit of energy will not be usable.)
The volumetric figures are most critical for phones, and in those terms batteries are 56x better than super-capacitors. So an improvement of 3x is interesting, but there's a lot more work to do.
Anyone remember the 1980's? Remember how the CMOS RAM on your PC's motherboard used to be powered by super capacitors before CR20xx batteries became cheap enough? Super capacitors have been around a loooong time.
Forgot to mention self-discharge rates: 0.007 C/day for LiPo batteries, and 0.08 C/day for super-caps (12x greater)
SuperCaps where not invented or even perfected by some 18 year old guy. They have been used as energy storage for a long time now, in newer times e.g. in professional-level SSDs to allow a clean data flush on power failure. They are completely irrelevant as energy source for cellphones as, despite their impressive capacities in the full-Farad range, they cannot store enough energy. The primary limiter is that they have low maximum voltages. And cellphones have some minimal energy requirements that cannot be reduced for the RF part.
I should also remind you that a modern low-current LED can be pretty bright at something like 1mA, and typically less than 5mW. That little will not get a cellphone to do anything.
Another clueless article from somebody that did not bother to find out any actual facts.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
Miracle! Anonymous Nobody invents magical new tech that will make everything better "real soon now" (usually about 3years),in the meantime go back to using your current tech and don't ask where the other marvellous new tech you were promised 3 years ago is now.. Wait for the next exciting installment same bat time, same bat channel :-\
Easy - switch mode supplies or simple transformers
220V 10A can be converted to 5V 440A theoretically.
Switch mode supplies can be 90% and above efficient.
About similar size to a desktop ATX PC power supply.
I hope it succeeds. It seems too good.
Very good for wind generators and solar fencing to capture
energy bundles as it waxes and wanes throughout the day.
Easy solution would be to have multiple smaller ones - I don't know enough electronics to know the advantages/disadvantages of having them in this situation in parrallel or in series, In this way, you might be able to "pop" charge your battery in very small increments. That is - have multiple small supercaps, that you quick charge, and have them hooked up to your battery (or even be the batery).
..........FULL STOP.
You could go the other way to solve this problem: make the batts/caps smaller and able to hold *less* charge.
Phone needs charge; Phone spends most of it's time in my jacket; Phone receives pwr from jacket pocket.
Jacket needs charge; Jacket spends most of it's time on the coat hook. Wire coat hooks to the mains electricity supply.
Planet needs charge; Planet spends most of it's time orbiting a star; Wire planet directly to sun;
Sun needs charge: Someone else's problem.
I'm not usually one to get petty about the summaries, but, "Charge your Cell Phone in 20 Seconds ..(eventually)".. eventually? That's just trolling at this point, if it's 3 years or more away. Not to mention the inherent dangers of a super capacitor.
Look back up at my post, now look back down, you're on the Internet. Now look back up. I'm a signature.
Well, then, go read the abstract at the ISEF site or the California State Science Fair (CSSF) web sites.. She was the Project of the Year at CSSF: http://www.usc.edu/CSSF/
Abstract here: http://www.usc.edu/CSSF/History/2013/Projects/S0912.pdf
Yes, she developed significant new approaches to building the internal structure (at a microscopic scale) of the capacitor, combining things in a novel way to get about 2 orders of magnitude improvement over other technologies. High energy density AND high charge/discharge rates at the same time.
Combined PVA coating on electrodes with a new way to make the electrodes with a lot of surface area AND with low electrical resistance. Previous techniques you either got lots of surface area (good for capacity, but bad for charge/discharge rate) OR low resistance (good for fast/charge discharge, but small capacity).
She's been successful at the fair for years. A very bright woman.
This is a 12th grade high school student competing in the science fair (and applying to colleges, taking AP classes and tests, etc.) I think she has more things to do than submit articles to refereed journals which would take a year to publish anyway. the abstract from the science fair is what you get today. You *could* have gone to the fairs in Los Angeles (CSSF) or Phoenix (ISEF) and grilled her all you like for details.
I would expect the journal articles in a year or so.. She has plenty of time this summer to write them.
Complain all you like, but it's the news media who are more interested in whether Beyonce is pregnant, whether Jodie will get the death penalty, or whether some kid will be a number 1 draft pick, than in incredibly talented high school students doing PhD level work.
Anyone can understand pregnancy, murder, and throwing a ball: Understanding how supercapacitors work, and what might improve them is well beyond most reporters; heck, looking through the comments above, I'd say it's beyond most slashdotters.
Most of this problem could be resolved if manufacturers made phones with slide-in, slide-out battery packs. One is charging while one is in use. Very simple system, been around for decades. No high-tech solutions needed.
Of course then they might lose the advantage of monitoring everywhere you go ... or being able to lock you in as a customer for *very* expensive battery replacements ... the only "reasons" I can see for doing the obvious thing of making a phone like a transistor radio or like a freaking flashlight.
"You must try to forget all you have learned. You must begin to dream." -- Sherwood Anderson
"Eventually" is a long time (approx 120 years at today's timescale expansion rates) and you can bet that by then the whole problem of adding energy to devices that need it will have been overcome by new developments.
For all men's sake we should all boycott this technology. I WONT LET THIS RECHARGE ALL VIBRATORS in 20 seconds... hell no. This will be the end of men's humanity as we know
that i cant jerk off 5 times a day like i used to. so writing comments on slashdot.. well, its almost the same thing.
Ordinary RAM is superior to flash memory in most applications.
Imagine a solid-state storage device that was essentially a flash device with a largish (GBs) capacitor-backed-up non-write-through RAM cache, with the cache only "writing through" when certain conditions existed, such as power loss.
You would only need a few seconds of juice on the capacitor and a smart onboard SSD controller to effectively make "wearout due to writes" a non-issue for most SSD applications.
Bonus points - I/O will almost always be at the faster RAM speed not the speed of the persistent storage chips (subject to limits imposed by the SATA or other communications interface, of course).
Heck, for "cheap" bulk storage skip the solid-state non-volatile stuff and just have a capacitor+ large RAM cache on a traditional spinning piece of metal. Hey, which is cheaper, a 4GB-RAM backed 750GB solid-state device or a 4GB-RAM-backed 750GB 2.5" drive?
Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
One think I rarely see mentioned is the discharge curve. Assuming a constant current load (this is a good approximation for a cell phone) the voltage decline will be linear! Much of the energy (unless you charge these to 10's of volts or greater) will be below the cutoff voltage of the device. The great thing about batteries is that their discharge curve is nearly flat in the middle of it's discharge cycle. In my opinion this is one of the greatest drawbacks to capacitor technology.
If you were to drop it in the bathtub, I imagine it would be instant death, no?
Can Tesla use this tech in their cars ?
My cellphone battery always dies
a. it's has a battery, it will eventually die of power.
b. STOP TEXTING too much. Maybe walk over to your friend's house instead.
There, problem solved...w/o a lot of time, money and education.
What? Our government wasted billions of dollars on this kind of research and an 18 year old kid solved the problem? OMFG!! The Oil Companies will be out of business in months, and the progressive utopian unicorn fantasy of renewable energy will come true! Nobody will have to work, or pay taxes, or do anything other than party and fornicate. Yippeee!!
Oh wait, it's just a salacious headline designed to get my attention.... with no basis in reality.
Thanks Slashdot. Betcha some nut job argues with me this week that the electric car with the batteries that recharge in 30 seconds has already been invented, and reminds me what a horrible, terrible person I am for driving a full sized pickup truck.
Murphy was an optimist
Agreed, probably longer.
The electric car in 1908 had a range of about 40 miles, and took 6-8 hours to charge. Back then a lot of folks thought all cars would be electric.
Fast forward one hundred years and the electric car has a range of about 45 miles, takes 4 hours to charge. Today, a lot of folks want all cars to be electric.
Do the math...
Murphy was an optimist