Cool! Yes it does promise a lot, but there's always the cost. I shouldn't have said that we can't store electricity efficiently, I should say that we can't store electricity in an economically feasible way. We can create amazing technology with simple batteries but the costs are simply too great.

even more on batteries...

Graphene oxide paper may spawn a new revolution

Washington, July 26 : Around 2,000 years after the discovery of paper revolutionized human communication, researchers at Northwestern University have now created a new kind of paper from Graphene, a sheet of carbon only one atom thick, which is remarkably stiff, strong and light in weight.

Although the researchers say that their invention will not replace the existing paper, they hope that it will create a revolution of its own by finding use in a wide variety of applications.

'The mechanical, thermal, optical and electrical properties of graphene are exceptional. For example, the stiffness and strength of these graphene-like sheets should be superior to all other materials, with the possible exception of diamond,' Rod Ruoff, John Evans Professor of Nanoengineering in the Robert R. McCormick School of Engineering and Applied Science, was quoted by Nature magazine as saying.

For making the graphene oxide paper, the researchers oxidized graphite to create graphite oxide, which falls apart in water to yield well-dispersed graphene oxide sheets. After filtering the water, the team was able to fabricate pieces of graphene oxide 'paper' more than five inches in diameter and with thicknesses from about one to 100 microns, in which the individual micron-sized graphene oxide sheets are stacked on top of each other.

'I have little doubt that very large-area sheets of this paper-material could be made in the future,' Ruoff notes.

Since the graphene oxide layers also have the quality of being stacking well, they may be the key to the development of other materials, say the researchers.

'You can imagine that these micro-scale sheets may be stacked together and chemically linked, allowing us to further optimise the mechanical properties of the resulting macro-scale object. This combination of excellent mechanical properties and chemical tunability should make graphene-based paper an exciting material,' Ruoff says.

The researcher also says that the graphene oxide paper has some electrical properties, which can be controlled without sacrificing its exceptional mechanical properties.

'When we oxidize the graphene sheets to create graphene oxide, the material goes from being an electrical conductor to an electrical insulator,' Ruoff says.

'This is an important step and in the future it will be possible to tune the material as a conductor, semiconductor or insulator. One will be able to control the electrical properties without sacrificing exceptional mechanical properties,' Ruoff adds.

The graphene oxide paper may be used in batteries or super-capacitors for energy applications. It may also be infused to create hybrid materials containing polymers, ceramics or metals, where such composites would perform much better than existing materials as components-such as airplanes, cars, buildings and sporting goods products.

--- ANI

source: http://www.newkerala.com/july.php?action=fullnews&id=49300

*****
What about this?

more batteries...

Unique Material May Allow Capacitors to Store More Energy
Posted on Friday, July 20, 2007 @ 23:02:52 PDT by vlad

Imagine an electric car with the same acceleration capability as a gas-powered sports car, or ultrafast rechargeable “batteries” that can be recharged a thousand times more than existing conventional batteries. According to physicists at North Carolina State University, all of these things are possible, thanks to their research on a polymer – or plastic material – that when used as a dielectric in capacitors may allow the capacitors to store up to seven times more energy than those currently in use.

NC State physicists Vivek Ranjan, Liping Yu, Marco Buongiorno Nardelli and Jerry Bernholc discovered how the electromechanical properties of the commonly used polymer polyvinylidene fluoride (PVDF) can be enhanced when combined with another polymer called CTFE.

Their findings, which explain an earlier observation of high energy density in these materials and point out ways to improve energy storage, will be published in the July 26, 2007, edition of Physical Review Letters.

Capacitors, like batteries, are a means of storing energy. Unlike batteries, capacitors don’t rely on a chemical reaction to produce the energy being stored. Instead, capacitors use polarization, the separation of positively and negatively charged particles, for energy storage. Part of this process involves applying an electric field to a dielectric material within the capacitor.

Dielectric material is usually a solid material that isn’t a good conductor of electricity – like ceramic, glass or plastic – but that will support an electrostatic field. When voltage is applied to a dielectric, an electrostatic field is created. The atoms within the material polarize, enabling the capacitor to store energy that can be quickly released on demand.

This ability to release large amounts of energy quickly makes capacitors especially useful in anything requiring quick acceleration times.

Physicists have long been interested in the electrical properties of the polymer PVDF, because it is known to be a dielectric material. In its solid state, PVDF can be either polar or non-polar, and it doesn’t change states when an electrical field is applied, leading to small energy storage. The researchers discovered that if they introduced “impurities” in the form of CTFE into a non-polar phase of PVDF, the resulting polymer had the ability to switch phases from non-polar to polar, enabling it to store and release much larger amounts of energy with a smaller electric field.

“Essentially we are moving atoms within the material in order to make the polymer rearrange with the least voltage,” Ranjan says. “We believe that we can tailor the atomic structure of the polymer to get the best performance in the presence of different electric fields as well.”

Source: NC State University
Via: http://www.physorg.com/news104161454.html

*******
Does this help?

Batteries...

Straddling a 619-pound motorcycle, Scotty Pollacheck tucks in his knees and lowers his head as he waits for the green light. When he revs the engine, there's no roar. The bike moves so fast that within seconds all that's visible is a faint red taillight melting in the distance.

Pollacheck crosses the quarter-mile marker doing 156 mph; he's traveled 1,320 feet in 8.22 seconds, faster than any of the gas-powered cars, trucks or motorcycles that have raced in the drag sprints on this weekend at Portland International Raceway.

It's particularly impressive given Pollacheck is riding a vehicle that uses no gasoline and is powered entirely by lithium-ion batteries.

...

source: http://www.businessweek.com/ap/financialnews/D8QMDGSO1.htm

Does this promise anything?

btw: regarding how it's meant for the army...what about at night?

These guys at MIT have found a way to potentially increase the efficiency of solar technology to 37% while reducing the cost per kWh http://www.technologyreview.com/Energy/18415/. This would be an amazing technology, but all these revolutionary ideas some a while off.

Different photovoltaic materials have varying electrical responses to light. Some materials will respond to infra-red, others to visible light, UV, etc. From memory I recall that these layers are composed of different materials (aluminum, gallium, and indium I think), and they mix them with nitrogen and arsenic as well. I'm not sure about the layers, but I know that research is being conducted into making one layer that absorbs virtually all sun light (most of the energy of sunlight is from the infra-red and visible spectrum) using these materials to create an alloy (http://www.scienceagogo.com/news/20021020210743data_trunc_sys.shtml). Using this sort of set up can result in efficiencies as high as 37% according to that website, which is more than double the efficiency you'd expect from the 10%-15% efficiency range of normal household panels(http://www.rpc.com.au/products/panels/pvmodules/pvmodules.html.

There are many ares of research in the Photovoltaic Solar Cell field. Just have a look on google you'll find dozens of different revolutionary new technologies. I think we're on the verge of a breakthrough in photovoltaics that could change the energy industry forever, someone just needs to make that final breakthrough...

...back to the ol' drawing board!

I heard of these a few months ago myself, it's a relatively old concept of splitting the beams, but making it financially viable is a totally different matter.

The models I heard about had 3 different layers of photovoltaic material (ie matieral that generates electric current from incident light), and each layer absorbed a certain range of light and let the rest pass through. Together they would absorb the entire visual spectrum and some infra-red light, increasing the efficiency by a certain amount (can someone tell me what that might be? Can't remember).

But I recall the problem being that for the extra cost (almost 3 times as much as there were effectively 3 panels in one) you might as well just by more panels with slightly lower efficiency. The overall cost per metre is still better for the cheaper less efficient panels. I guess the appeal for the military (as mentioned in the article you linked) is that there's only so much room on a guy's backpack, so you need all the efficiency you can get. But yeah 40% is HUGE, that must be getting close to the efficiency of photosynthetic organisms...