[ChuckMcM]

Excuse me? This from the linked article (and in the paper abstract):

"These micro-supercapacitors demonstrate a power density of ~200 W cm−3, which is among the highest values achieved for any supercapacitor."

Granted its not a legitimate energy density (wrong units) but lets guess it is 200 Ws per cubic centimeter. I make that guess based on the comment in the video that they ran an LED for 5 minutes. So an LED is like 15mA and with a forward drop of a couple of volts so 30 mW. For 5 minutes your looking at 9000 mW-seconds, or 9 Ws for the small capacitor they showed in their video which could have been about a cm ^ 2. So if the cell they had made was 1/2 mm thick then a stack of 20 of them would be 1 cm^3 and 180 W-seconds (in the ball park of the abstract). There is a fun presentation on Supercaps [1] that was given to DoE in 2011. This computation does suggest that 200 Ws for this material would be a decent jump in capacity.

That said, I immediately dug an old LightScribe CD recorder out of my junk bin to start playing around with making graphene sheets :-)

[1] http://www1.eere.energy.gov/vehiclesandfuels/pdfs/merit_revi...

[wamatt]

>That said, I immediately dug an old LightScribe CD recorder out of my junk bin to start playing around with making graphene sheets :-)

You serious? Sounds interesting, do tell us more.

[ChuckMcM]

Of course I am serious! Still trying to figure out what they used as a 'base' graphite oxide slurry (pencil lead in solution it isn't)

[lambdasquirrel]

That's still power density. Power is Watts. Total energy is joules. You haven't addressed the parent's concern. We are interested in how long it can keep up that wattage, ie. joules/sec.