Super super capacitor:?

A traditional supercapacitor is basically two hunks of activated charcoal floating in electrolyte. Due to ions in solution and properties of the surface, an electric bilayer forms around the surface of the charcoal (which has a *lot* of surface), which resists current flow over a certain range: it has a deadband within which the layer is stable. This voltage is about 1.2V for water, but the organic solvents used in supercapacitors tolerate up to 2.8V or so. That's pretty remarkable, chemically, when you consider it's the same voltage a hunk of magnesium achieves while dissolving in water!

The main downsides are, activated charcoal is a crude material, and though it has a lot of surface area, it isn't very well connected (ESR depends on the average path length to any given point in the mass), so the resistivity is way worse than, say, a conventional metallic electrode (electrolytic or film types), and the performance nowhere near a battery's.

Indeed, one can easily build a supercapacitor at home: press a cake of charcoal against a graphite terminal for each electrode, sandwich two electrodes around a paper divider, and moisten with salt water. Several farads can be easily achieved, but the average ESR is so massive, it takes minutes to fully charge or discharge! The best commercial products basically address this with very thin layers of electrode, spiral construction, high conductivity electrolyte, and probably some special processing on the charcoal.

The holy grail would be, say, alternating graphite sheets connected to each electrode, just like a stacked film capacitor, on the nano scale. This could be made extremely small (assuming it could be made at all). A less aggressive approach might use wads of graphite (graphene paper, perhaps), rolled up much like an electrolytic. This might be closer to what they're demonstrating.

Ultimately, since we're talking separation of charge, no type of capacitor can ever achieve the energy density of a battery (which still works on separation of charge, but on the atomic scale, not molecular or higher). That said, today's batteries, though constantly improving, are probably on par with an ideal theoretical capacitor, so there is plenty of room for improving both.

Tim

Cool video.

"Ric Kaner set out to find a new way to make graphene, the thinnest and strongest material on earth. What he found was a new way to power the world."

Right. To match gasoline, he needs 35MJ/L, or about 11kF/cm^3 for a

If lead-acid batteries were 550x better, you'd only need 5kg of 'em for a pretty decent car.

Cool video.

"Ric Kaner set out to find a new way to make graphene, the thinnest and strongest material on earth. What he found was a new way to power the world."

Right. To match gasoline, he needs 35MJ/L, or about 11kF/cm^3 for a

If lead-acid batteries were 550x better, you'd only need 5kg of 'em for a pretty decent car.

The research (and funding) soon follows:

"... will work with industrial partners including Nokia, BAE Systems, Procter & Gamble, Qinetiq, Rolls-Royce, Dyson, Sharp and Philips Research - which will together bring in a further £12m in investment."

I can see it now... A graphene powered cell phone (Nokia), with military applications (BAE), which will do the laundry (PG and QinetiQ), power the Rolls-Royce electric luxury car, run an electric vacuum cleaner (Dyson), run a 3D TV (Sharp), and power an off grid LED lamp (Philips). More power to the conglomeration.

Perhaps it would be best to start with smaller applications before taking on the electric car problem. For example, I could certainly use longer battery run time and life for my smartphone and laptop:

The actual performance data, notably absent, is eagerly anticipated by all.

perhaps cabon nanotubes instead of charcoal sponge.

graphene whilst thin has no more surface area than the aluminium foil you're replacing with it .

Real numbers will eventually appear, but only after research and startup funding arrives. Meanwhile, amazing claims of spectacular performance will predominate.

Real products? No problem:

I found this attempt to produce usable numbers. Never mind the article. The confusion is in the readers comments, which like your numbers, didn't include any useful references or sources. There was originally two papers on the topic (probably with usable numbers) that were attached to the story, but the links don't work.

This is as close to real numbers as I could find: "Graphene-Based Ultracapacitors" Unfortunately, they provide only Farads/gram, which isn't particularly useful.

Meanwhile, progress in storage technology has found a possible solution to making practical lithium-sulfur batteries, which can then be labeled as having "natural" and "organic" sources:

Then, there's the see through battery:

Many such promising technologies die a silent death in the research lab as unforeseen difficulties and complications emerge during the development. 20 years later, they are then resurrected by someone able to solve these difficulties, and emerge as the next miracle products. Have patience please.

Actually, laptops are getting better. Lately I've been seeing 13H battery life advertised, 24H with the additional (attached) battery "slice". My new one (not one of the above) is running just short of

Yep:

It's not so much the battery, but rather that the laptops have been drawing less power. An easy way to check is to look at the wattage on the battery charger. The convention is to supply a charger that is capable of running the laptop with the battery removed. Therefore, the nameplate power will be slightly higher than the max power consumption. In the distant past, I've seen 130 watt adapters the size of a larger brick. They've been slowly going down to about 45-65 watts these days. With energy saving features in the CPU and attached devices, the ratio of average to peak power is dropping. Leaving out the CD/DVD drive, changing to LED backlighting, and using SSD drives have also contributed to the power reduction.

If you wanna do your own testing:

On a sunny day (Sun, 30 Dec 2012 16:32:26 -0800 (PST)) it happened snipped-for-privacy@yahoo.com wrote in :

Hey, but powering your flashlight from a DVD is cool man, just find some matching carbon music :-)

I tell you one thing, if every publication for a 100% improvement of batteries was true, you could power NY fro ma suger cube by now :-)

I have not rated that video, for the same reason, but their way to make graphene is nice :-)

On a sunny day (Sun, 30 Dec 2012 20:36:58 -0800) it happened Jeff Liebermann wrote in :

What happened to that Japanese professor who would demonstrate a procuction model of his cold fusion demo eeeeh, 6 years ago?

Sure, my point was an aside. Laptop battery life comes up here quite often. I was surprised things had gotten significantly better since I last looked.

One I almost bought had a 170W adapter, so they aren't all coming down. I believe the power hog is USB, on these. Apple has done a number on USB power requirements. Though it's not really a "USB" issue, everyone has to follow anyway.

LED backlighting is a biggie. CPUs use less power, now, too. When I was in CPU development, everything was balls-to-the-wall CPU performance, damn the power. They can't push the speed up, anymore, so they seem to be optimizing for power.

I'm not big on putting unnecessary cycles on my laptop batteries.

The 35MJ/L was from Wikipedia. 20F/cm^3 was told to me by someone who's actually doing it. I think I posted links last time this came up.

Oddly enough, Rolls-Royce PLC do not make cars, they make aircraft and military vehicle engines. Rolls-Royce cars are made by BMW.

Well, if there was supposed to be a video of some sort, it is gone: tho the black rectangle might be called a virtual graphene film..

model

I didn't hear of him, but an Italian researcher was to be in production of a heating system based on cold fusion a couple of years ago. Discussion of his system seems to have waned so I assume he stopped talking about it once he repeatedly missed his deadlines.

Rick

What about actual battery life, I mean when the battery capacity drops to where it is no longer usable. I've been tethered to a wall outlet for a couple of years now. I think it ran ok for a couple of years, but was never much more than a hour and a half. I got one of those barn burner AMD machines.

Rick

model

I wonder how much "venture capital" he found before he stopped talking (A.K.A. disappeared).