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Phoenix666 [soylentnews.org] writes:

With tiny but powerful capacitors [ieee.org] you could make cheaper, even tinier cardiac pacemakers and computers. They’d be great in nonvolatile memory, microsensors and actuators, RFID tags, and microelectromechanical systems, applications in which the power supplies can weigh up to 10 times as much as the other parts combined. And because, like all capacitors, such devices would be able to release their charge very rapidly, they could be coupled with high-energy batteries to provide periodic surges, as conventional capacitors do to power the flash in smartphone cameras. (Miniaturized supercapacitors could thus lead to even thinner smartphones.)
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We found the solution in LightScribe, an inexpensive, off-the-shelf laser technology that millions of people have used to etch labels and designs onto compact discs. However, instead of using a disc coated with a reactive dye that changes color on exposure to laser light, we use a very thin coat of graphite oxide. The laser heats the oxide, transforming it into graphene in precisely defined tracks, one micrometer apart. These are the electrodes. In between we leave untreated graphite oxide, which conducts ions but not electrons and so can serve as an excellent dielectric between the positive and negative graphene electrodes. To complete the cell, we top off the pattern with a droplet of gel electrolyte to provide a bit of battery-like storage—the same technique that’s used in conventional supercapacitors.

The article is verbose, but has more information about their process.

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