Why energy storage is really superficial

If you want to improve the performance of batteries and capacitors, one sure-fire way is to increase charge density. And the way to do this is to up-scale the surface area of your electrodes. Various configurations of carbon, both alone and in combination with other elements, can provide that increase, which is why we have reported on everything from nanoflowers to a carbon nanofoam.

The latest news in the battle for increased surface area comes from Rice University, where scientists have seamlessly combined carbon nanotubes a few atoms wide and 120 microns long onto one-atom thick graphene sheets, reports Science Daily. That means that if the nanotubes were the same width as an average house, they would rise up from the graphene ‘ground’ like mega-skyscrapers… into space.

As you can imagine, that’s a lot of surface area: 2,000 square metres per gramme of material, in fact. But what about practical applications? Researchers at Rice say their tests indicate the material already performs as well as the best carbon super-capacitors.

Advertisements

San Diego zoo debuts energy storage

It converts sunlight into energy, charges electric vehicles and delivers access power to the grid. And it keeps your car cool while you go feed the elephants. The newly unveiled parking lot at San Diego zoo has solar canopies that can produce up to 90kW of electricity, five car-charging stations and the possibility to deliver energy to the grid. Best of all, it has two lithium-polymer storage units, with a total capacity of 100kW.

According to an article on the KPBS site, the energy storage element is a first for this type of project. And the installation has so impressed the University of California in San Diego that it is considering building a similar power hub on campus.

US ups spending on energy storage

Steven Chu, President Obama’s Energy Secretary, has been making the case for a modest 2.3% increase in the renewables investment, reportsRenewables Biz. This would bring the total spend to USD$27 billion, of which $60 million has been earmarked for researching and expanding the uses of energy storage systems. The money would be in addition to $185 million given to 16 different storage projects via the 2009 stimulus plan.

Is this sort of spending a good deal for the US taxpayer? Although not directly related to energy storage, some Department of Energy figures, as reported in GreenTech Media, suggest it is; the Government says every tax dollar invested in solar projects attracts 20 more in private money. If true, then surely this is the sort of market distortion most of us can live with.

Scientists reveal lithium-ion secrets

Physicists at the US Department of Energy’s Brookhaven National Laboratory and collaborating institutions have developed methods of examining lithium-ion reactions in real-time to a nanoscale (billionths-of-a-metre) precision, offering unprecedented insights into processes that are vital to battery technology, reports NanoWerk.

“(L)ive, nanoscale imaging may help pave the way for developing longer-lasting, higher-capacity lithium-ion batteries. That means better consumer electronics and the potential for large-scale, emission-free energy storage,” commented Feng Wang, one of the key researchers on the project.

US molten salt project gets green light

The US solar developer SolarReserve this weekconfirmed it has received the final Arizona State approval required to go ahead with its Crossroads Solar Energy Project. This aims to supply approximately 500,000MW annually of reliable, sustainable, zero-emission electricity to Arizona or California, enough to power up to 100,000 homes during peak electricity periods, says the company.

The project comprises 150MW of electrical generating capacity using concentrating solar power, plus 65MW of additional solar photovoltaic technology. Up to 10 hours of solar energy per day will be stored using the company’s molten salt power tower technology, says SolarReserve. Construction of the site, near Gila Bend, should begin late this year, or in early 2013.

New solar storage possibilities from MIT

Scientists at the prestigious Massachusetts Institute of Technology (MIT) have produced modified carbon nanotubes that can store solar energy indefinitely after being charged up by sunlight, says the university.

Although nano materials that store sunlight in chemical bonds have been produced before, researchers on this project say that the new material, which is made using carbon nanotubes in combination with a compound called azobenzene, has a much higher energy density than earlier solutions. In fact the energy density of this solutions is comparable to that of lithium-ion batteries.

Saft in new USD$98m deal with US military

Saft will be providing the US Defense Logistics Agency (DLA) with lithium-sulphur dioxide batteries for portable devices such as radios,reports New Energy Network. The DLA will then pass the units onto the US Army, Navy, Air Force and Marines.

The contract Saft has secured will be worth up to USD$98 million over five years and adds to the recent top-up of $1.3 million the company secured from BAE Systems to develop energy storage solutions for hybrid vehicles destined for the US Army.