Posted on 09/01/2010 1:34:35 PM PDT by LibWhacker
If optimized, this new technology could fully charge consumer electronic devices almost instantaneously.
Drawing on the layered design of tear-inducing onions, scientists have created a new super capacitor that is powerful enough -- and cheap enough -- to replace the larger, heavier capacitors used in consumer electronics such as computers and cells phones.
If commercialized, the new super capacitor could be fully charged in a second and, coupled to a normal battery, provide enough energy to power a cell phone for weeks or a laptop battery for days.
"If you open any computer, you will see a lot of these small, cylindrical round capacitors," said Vadym Mochalin, a scientist at Drexel University and a co-author on the new Nature Nanotechnology paper.
Capacitors, like batteries, store energy, but that's where most of the similarities end. Generally speaking, a battery, like the one inside your cell phone or laptop computer, stores energy chemically. That chemical energy is then converted into electrical energy.
Converting electrical energy into chemical energy and vice versa is a relatively slow process, which is why the lithium-ion batteries in laptops and cell phones can last for hours or even days but also require a long time to charge.
A capacitor is different. Simply put, a capacitor stores an electrical charge between two conductive plates separated by an electrical insulator.
Without the chemical-electrical conversion, a capacitor can be charged and discharged much more rapidly than a battery, last longer and weigh less. Capacitors are ideal for camera flashes and other electrically intensive consumer devices.
However, in contrast to batteries, a capacitor cannot store enough energy to power anything that lasts longer than a flash -- some fraction of a second.
Super capacitors, however, store much more energy than their traditional counterparts and are used to power small devices such as toys including model planes and helicopters.
In the future, super capacitors will be more powerful and replace batteries in more and more devices. Super capacitors or "electric double layer capacitors" store charge in a layer of ions adsorbed on the surface of carbon.
The new super capacitor began its electrically charged life with a literal bang. A powerful blast, usually hexagen or TNT, converts carbon contained in the molecules of explosives into a thin sheet of nanodiamonds.
The researchers then transformed those nanodiamonds into dozens or even hundreds of graphene layers, all nestled inside one another like little Russian dolls.
When the graphene "onions" are bathed and charged in an organic electrolyte, they can discharge up to 200 volts every second. If the technology is optimized that number could be further increased several times, said Mochalin. That would be enough to fully charge a cell phone, laptop or other electrical device almost instantaneously, and then dole out that power to a waiting battery for long-term storage.
The performance is excellent, and if commercialized -- something the Drexel scientists are working on -- the price should be right as well. The diamonds found in jewelry are expensive, but nanodiamonds are cheap. A few hundred dollars will get you a pound of nanodiamonds, said Mochalin.
"You need an electrically conductive material for a capacitor, and diamonds are insulators," said Olga Shenderova, a nanodiamond expert at the International Technology Center in North Carolina.
Additionally, by using a material that is relatively inexpensive, said Shenderova, the research could eventually lead to a whole new generation of super capacitors.
Before you get too excited, find out how many watt hours hours a unit can hold, then look at your electric bill, remember your use is measured in kilowatt hours. During the summer, I go through millions of watt hours running the air conditioner.
If you convert horsepower to kilowatts, your car engine output is probably over 100 kilowatts. It take about 25 kilowatts (25,000 watts!) to push your car at highway speeds.
If commercialized, the new super capacitor could be fully charged in a second and, coupled to a normal battery, provide enough energy to power a cell phone for weeks or a laptop battery for days.Probably take care of running a taser for a couple of hours.
Coulombs.
Redundant.
...and blacks out your whole neighborhood during that five minutes...
See # 46...
Good point, that is what a capacitor does when it fails, and then they explode or something weaker in the circuit will fail causing more and harder to troubleshoot problems.
Super caps as a battery replacement is not doable, never will be, rechargable batteries already fill that void and that's what they should be focused on.
I’m disappointed in FR that it took 20 posts and 40 minutes for somebody to post that. Yes, you win!
Remember the batacitor of Ringworld?
Ha ha
~~~~~~~~~~~
Supercaps are already being used on a small scale for battery replacement. There are several types of RC toys that use them (and are quickly recharged from dry cells). Also, I suspect that those "shake and use" LED flashlights employ supercaps.
There is no question that a large-capacity supercap (without internal limiting mechanisms) is a distinct safety hazard. But, the same thing applies to similar-sized batteries. (Remember the flaming laptops...?)
If I understand the article correctly, the plan is to pair supercaps with batteries. The supercap would accept the quick charge, and then would depete its charge by "trickle-recharging" the battery to spread the use out over a long time scale.
The problem of a high peak-current charging source for the supercap remains, however...
Probably a strategy like used in the toys would work: Supercap charging stations that are "trickle-charged" from the grid and that then can quickly dump part of that charge into the mobile power-supply supercap should be workable. That would reduce the peak load on the grid, while taking advantage of the fast-recharge properties of the mobile supercap/battery pack...
After a career in high tech, (semiconductors and micromechanics) I have learned that "...is not doable, never will be" is frequently a position that will come back and bite you in the rear... ( I remember something like that being said about superconductivity, for example...)
My wool rugs can charge me up to 50KV!
An analogy is the RC helicopters that are quick-charged by the battery packs in their RC hand control units.
Actually that might be a workable strategy for using the variable output of wind or solar generation (as in the "shaker" flashlights)...
(Of course, the things would have to be armored or otherwise shielded against terrorists with AP weapons...)
pang
Yeah, I know it is the same kilowatt hours, and yer gonna pay for them one way or another. I just find the idea of vast amounts of electricity delivered to your door in a state you can use and without wires to be intriguing.
Someone else mentioned that to me recently. I’m sorry to say I never read it.
Did read your comment on your FR homepage about the spread of islam, however... ‘twas a thing of beauty, thanks! Well done, sir.
You say that like it is a bad thing...
;)
1.21 Jigawatts?! Tom, what was I thinking?!
“For with a supercapacitor, the car can be ‘refueled’ in less time than it’d take to refill your gas tank.”
Let’s say your electric supercapacitor car takes 15,000 Watts to run at some nominal speed. Now run it for four hours, that’s 60 Kilowatt-Hours.
If you were to recharge that capacitor in one second, the power required would be 216 megaWatts.
If it’s a 12 Volt system, you’d need to run 18 million Amperes.
There are practical limits to how fast you can charge a capacitor.
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