Saturday, February 23, 2013

More Good News About Supercaps

Looks like I am going to win my bet.
That battery life video that had gone viral due to a recent post on UpWorthy (and which we told you about Tuesday) now has an update. We told you that researchers at Ric Kamen's lab at UCLA had found a way to make a non-toxic, highly efficient energy storage medium out of pure carbon using absurdly simple technology. Today, we can report that the same team may well have found a way to make that process scale up to mass-production levels.


The recap: Graphene, a very simple carbon polymer, can be used as the basic component of a "supercapacitor" -- an electrical power storage device that charges far more rapidly than chemical batteries. Unlike other supercapacitors, though, graphene's structure also offers a high "energy density," -- it can hold a lot of electrons, meaning that it could conceivably rival or outperform batteries in the amount of charge it can hold. Kaner Lab researcher Maher El-Kady found a way to create sheets of graphene a single carbon atom thick by covering a plastic surface with graphite oxide solution and bombarding it with precisely controlled laser light.
English translation: He painted a DVD with a liquid carbon solution and stuck it into a standard-issue DVD burner.
The result: Absurdly cheap graphene sheets one atom thick, which held a surprising amount of charge without further modification.
That work was reported a year ago; we mentioned it due to the video virally making the rounds this week. Late Tuesday, UCLA announced that El-Kady and Kaner have a new article in press, in the upcoming issue of Nature Communications, describing a method by which El-Kady's earlier, slightly homebrewed fabricating process shown in the video can be made more efficient, raising the possibility of mass production. As the authors say in their article abstract,
More than 100 micro-supercapacitors can be produced on a single disc in 30 min or less.
El-Kady and Kaner found a way to embed small electrodes within each graphene unit, and place the whole thing on a flexible substrate that allows the supercapacitor to be bent. The team is already claiming energy density comparable to existing thin-film lithium ion batteries.
In the video we shared Tuesday, Kaner says that this technology, if it pans out, offers possibilities like a smart phone getting a full day's charge in a second or two, or an electric car reaching "full" in a minute. This week's press release from UCLA offers other intriguing possibilities:
The new micro-supercapacitors are also highly bendable and twistable, making them potentially useful as energy-storage devices in flexible electronics like roll-up displays and TVs, e-paper, and even wearable electronics. The researchers showed the utility of their new laser-scribed graphene micro-supercapacitor in an all-solid form, which would enable any new device incorporating them to be more easily shaped and flexible. The micro-supercapacitors can also be fabricated directly on a chip using the same technique, making them highly useful for integration into micro-electromechanical systems (MEMS) or complementary metal-oxide-semiconductors (CMOS). As they can be directly integrated on-chip, these micro-supercapacitors may help to better extract energy from solar, mechanical and thermal sources and thus make more efficient self-powered systems. They could also be fabricated on the backside of solar cells in both portable devices and rooftop installations to store power generated during the day for use after sundown, helping to provide electricity around the clock when connection to the grid is not possible.
Kaner says that his lab is now looking for partners in industry that can help make these graphene supercapacitors on an industrial scale.
It's tempting to be cynical about the possibility of a magic bullet energy storage solution; such a breakthrough could solve any number of problems from annoying dead smart phones to two-hour charge times for electric cars to an inefficient power distribution grid, and it's easy to really want this kind of thing to be true. Plenty of seemingly promising technical innovations in the last few years haven't lived up to their hopeful hype. There's always the chance that further study will reveal a fatal flaw in graphene supercapacitor technology. 

1 comment:

  1. This is incredible - you did an amazing job!!! Less-than-perfect sheets of atom-thick graphene show unexpected weakness, according to researchers. Graphene Information: Learn about the use of Graphene in Graphene ultra- and supercapacitors, Graphene Transistors and Graphene Batteries. Thanks for sharing.....Graphene Battery

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