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Breakthrough In Use of Graphene For Ultracapacitors
Hugh Pickens writes "Researchers at the University of Texas at Austin have achieved a breakthrough in the use of a one-atom thick graphene for storing electrical charge in ultracapacitors. They believe their development shows promise that graphene could eventually double the capacity of existing ultracapacitors. 'Through such a device, electrical charge can be rapidly stored on the graphene sheets, and released from them as well for the delivery of electrical current and, thus, electrical power,' says one of the researchers. Two main methods exist to store electrical energy: in rechargeable batteries and in ultracapacitors, which are becoming increasingly commercialized but are not yet well known to the public. Some advantages of ultracapacitors over traditional energy storage devices such as batteries include: higher power capability, longer life, a wider thermal operating range, lighter, more flexible packaging and lower maintenance. Graphene has a surface area of 2,630 square meters, almost the area of a football field, per gram of material."
2D area vs mass. What that statement was trying to get across was that graphene is so thin that you could almost cover a football field with only a gram of it. Think of spreading cream cheese on a bagel. You only have a gram of cream cheese, though, so you have to spread very, very thin. Except the bagel is the size of a football field, so you have to spread it even more ridiculously thin: only an atom thick. Now instead of cream cheese it's carbon atoms.
"A witty saying proves nothing." - Voltaire
I found this image from Nature magazine useful in imagining how 1 gm of graphene can have such a large surface area..
http://www.nature.com/nature/journal/v427/n6974/fig_tab/nature02311_F1.html
"Laziness is an optimisation protocol"
Human resource usage expands to consume all available resource...
That is the history of humanity in one sentence. In fact, it can be generalized to all life.
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I know you're trying to be cleverly ironic here, but you can buy ultracaps today. The higher power capability, swifter charging, longer life, wider thermal operation range, more flexible packaging, and lower maintenance are already there and have been for years along with the superior environmental characteristics. However, "lighter" isn't true yet, since the energy density of an ultracap is an order of magnitude lower than that for a dry cell. That's why a breakthrough such as in this article is such a big deal.
If grapheme could reliably be utilized to create the sort of energy density posited here, any application requiring large amount of batteries (such as electric cars) would benefit greatly. Unfortunately, since capacitors are more prone than dry cells to losing energy over time due to internal resistance, this won't eliminate the need for dry cells entirely.
You like splinters in your crotch? -Jon Caldara
That's one of the serious problems with any exceptionally high density energy storage technology. How do you keep the genie in the bottle, and protect the public from the critically stupid in our society.
There was a very cool design for a car whose power source was a high mass flywheel in a magnetic housing. You go to a power station, and the station would spin your flywheel up to some insane RPM rate. The possibility of using this in a hybrid vehicle meant you could get really excellent energy storage and return, it was very efficient.
The only drawback, was that if the bloody thing ever got out of containment, you had a death dealing juggernaut that would buzz-saw a swatch of destruction through the middle of wherever the now flying flywheel was pointed. Then some bright child imagined such a flywheel driven vehicle on a crowded freeway causing a chain reaction of thousands of other similar vehicle, and suddenly you pretty much have a scenario for mass destruction that looks like front row seats to Armageddon.
Whatever technology you finally pick, you'll need to make it very safe, or decide it's a Darwinian herd thinning tool.
Because it doesn't have to layers that are insulated against each other?
However, if you're talking about two toiled rolls, soaked in electrolyte, with an insulator between them, rolled up and packaged nicely, then yes, you can use that as a capacitor (we'd all be thrilled about a capacity measurement and some pictures when you try it out, please?).
Don't worry that the Graphene layer would rip. It's a very, very strong material and the connections between the atoms are strong conjugated double-bonds.
This is the same structure as in Carbon Nano Tubes and Fullerens (C60), just flat (and not cylindrically or spherically rolled up).
The problem to implement Graphene based technologies is rather the synthesis of it, since it's not yet easily possible to create a homogeneous Graphene layer on a large area (i.E. at my Applied Physics institute they create Graphene layers that are not even 1 mmÂ).
If you wanted a thin layer of carbon, wouldn't it be easier just to toast the bagel?
No. This isn't even close to EEStor's claimed energy density. I personally put EEStor in the BS bucket a long time ago, but last week I found some very interesting news on wikipedia's EEStor page: competitors. It seems that several companies now have patents on materials they claim are similar in energy density to EEStor's claims. We may not get ultra-cheap batteries for electric cars any time soon, but at least the raw science seems to be real.
Beer is proof that God loves us, and wants us to be happy.
Or until we invent fertilizer (18th century)...for food
Or until we invent pesticieds/herbicides...for food
Or until we invent underground farming...for food
Or until we invent land reclimation...for land
Or until we invent skyscrappers...for land
Or until we invent seasteading...for land
Or until we invent lunar colonies...for land
Or until we invent large dams...water, food and power (oil)
Or until we invent water treatment...water
Or until we invent reverse osmosis distillation...water
Or until we invent atmospheric condensers...for water
Or until we invent nuclear fission...for power (oil)
Or until we invent fusion...for power (oil)
Or until we invent photovoltaics...for power (oil)
Or until we invent bio fuels...for power (oil)
Or until we invent direct CO2 conversion to hydrocarbons...for oil (from power)
and a big one is:
Or until we invent a trully good electrical battery, one that stores a lot of energy, has high power density, does not wear out, does not use environmentally harmfull components and is cheap (something like these graphene supercapacitors will be under mass production)...for oil
My point is simple. Humanity ran out of resources about 20,000 years ago. We are designed to be hunter/gatherers. The earth can only support a few million hunter/gatherer human beings. It was only through the invention of agriculture and other technologies that we are able to continue. While we will probably ALWAYS have some resource limitation (probably power) there are technologies that exist now that if used can prevent any Malthusian collapse for the indefinet future.