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."

Comments

advantages of batteries

[loshwomp]

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.

By contrast, two advantages of batteries are 1) vastly higher energy density, and 2) the fact that they exist.

Re:advantages of batteries

[OldMiner]

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.

Re:How?

[cryptoluddite]

Generally things that are one atom thick are much more fragile than things that are millions of atoms thick. When they get this working in cars and not 'losing capacity' aka frying you when you go over a speed bump it'll be a pretty good replacement for batteries...

Re:Cost.

[kestasjk]

Depends; we don't yet know how to commercially make graphene. This is a shame because in addition to ultracapacitors it could also be used to make integrated circuits. It's the same problem as with nanotubes; lots of great uses already found, now we just need to figure out how to make them.

Re:surface area of a football field

[Ihlosi]

If 1 gram of graphene has the surface area of a football field, what's the surface area of a football field of graphene?

One football field, of course. They're both units of area. Now, if you were to ask what the surface area of a VW-Beetle-equivalent of graphene is ...

Here's the deal

[Colin Smith]

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.

 

Re:Here's the deal

[srussia]

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.

Agree with your first statement. The difference, however, between humanity and other forms of life is that humans increase available resources in order to be able to expand usage.

Re:Here's the deal

[HungryHobo]

We don't seem to have expanded to use all oxygen yet, we don't seem to have used up all the salt water, both are freely available to a great many people.

Human resource usage expands to quite a high point but to assume it's infinite is a little presumptuous.

It was assumed that the human population would continue to increase exponentially but in some developed nations we're seeing a birth rates drop below 2 children per couple.

People multiply insanely when the chance of their children reaching adulthood is low, people try to obtain stupidly large amounts of resources when resources are scarce.
Average resource usage may not increase forever. It'll probably still has a way to go but I can see the average leveling out at some point.

Re:Here's the deal

[lisaparratt]

You think our atmosphere always had this much oxygen in it?

Safety ?

[CdBee]

Ultracapacitors may have proven brilliant usages (especially in transport and electricity storage) but is anyone else nervous about being around that degree of stored energy?

As a teenager I was slightly injured by a 50-year-old 3300mfd cap I'd salvaged from a valve radio, which went off like a small bomb despite only holding 12 volts at the time. I for one would treat an ultracapacitor as a potential source of devastation until proved safe by a long period of use...

Re:Safety ?

[CdBee]

Thanks, that was part of my point. Capacitors have in common with Lead-Acid accumulators the ability to dump biblical amounts of power in an instant... and it may be easier to unthinkingly short a circuit than it is to unthinkingly introduce a flame to a fual tank

I drive a diesel car. It feels safer (low-volatility compared to petrol)

Graphene's properties

[JSchoeck]

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).

Re:Still...

[somersault]

First poster didn't seem to. Times were when you only got 1.5 hours of word processing time, and these days people have their wifi enabled all the time. Anyone with a mobile phone will know that that is a major drain on the battery. We're getting the same battery life as before, but we're able to do much before in that time.

By the time affordable ultracaps everyone will probably be complaining of 'only' 11 hours solid gaming usage on their laptop.

It's all a manager of energy

[maillemaker]

The fact of the matter is, it takes "X" number of joules of energy to move your typical car 300 miles.

Whether that energy is stored in a tank of gasoline, a capacitor, batteries, or a spinning flywheel, you still have X number of joules of energy that have to be safely stored and protected against unrestrained liberation.