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Material is called "the most condensed form of energy storage outside of nuclear"

Calling the material "the most condensed form of energy storage outside of nuclear energy," the researchers created the super-battery inside a diamond anvil cell, a small chamber that can create extremely high pressures within a confined space. The team filled the chamber with xenon difluoride, a white solid usually used to etch silicon conductors.

The science is in the squeezing; under normal atmospheric conditions, the molecules of xenon difluoride keep a respectable distance from one another. But under the intense pressures produced by the diamond anvils the molecules are forced together into metallic 3-D structures. At one million atmospheres -- roughly equivalent to the pressure found halfway to the center of the Earth -- the xenon difluoride is pressed neatly into these structures where the mechanical energy of all that pressure is stored in the chemical bonds between the molecules.

And just like that, the material becomes a chemical battery containing the mechanical energy from all that pressure. That raises the possibility of practical applications such as high-energy fuels, high-powered and compact batteries, or semiconductors that can function at very high temperatures.

[Science Daily]

Lithium is cheap and widely available, so why do we care about a new resource in a war zone? Because it’s another counter to the irrational fear that the automobile’s lithium-powered electric future is doomed before it begins

Drowned in the noise, however, was a fascinating bit of news: that just this month a Pentagon team was hunting for minerals in Afghanistan’s dry lakes, and that early findings suggested that one site alone might contain more lithium than Bolivia’s Salar de Uyuni, which is believed to hold up to half the world’s known supply.

Why is this significant? Because even if Afghanistan’s lithium never leaves the ground, the sudden, black-swan appearance of a new and potentially massive resource helps further debunk the myth that the world is running out of lithium and that, as a result, an electric-car revival that relies on lithium-based batteries is doomed before it begins.

Too much of the coverage of lithium seems to be driven by the idea that it is slightly more rare than unicorn hide. It’s not. Extremely conservative estimates from the USGS peg world lithium reserves at 9.9 million metric tons, and the number is almost certainly much higher. By contrast, in 2008 (because of the recession, 2009 was an unrepresentative year) the world’s lithium mines produced 25,400 metric tons. Those mines will need to produce more in the coming years as lithium-ion batteries start going into cars, but that shouldn’t be a problem: more than 100 companies worldwide are moving into the market.

If lithium isn’t rare, however, it is unfamiliar and misunderstood. It is an exotic, intriguing element—the lightest metal in the periodic table, and therefore the ideal carrier ion for a battery. It has been called “the yeast in the dough” of the most advanced batteries we have today, the power packs that will drive the Chevrolet Volt and the Nissan Leaf, both of which arrive later this year. Most of the blue-sky battery technologies in the lab now are designed to surpass lithium-ion batteries by jamming far more lithium atoms into their electrodes per unit volume and mass, thereby storing more usable electrons, so lithium will be an essential element in the construction of a clean-energy future. That’s a very good reason to pay close attention to the countries and the companies that produce it. But that doesn’t mean there’s not enough of the stuff to go around.

Here’s the backstory on the Afghanistan mineral findings. In 2007 the USGS published an estimate of Afghan mineral resources that showed that the country contained vast untouched deposits of iron, copper, rare-earth elements and other high-demand minerals. The report barely touched on lithium, simply mentioning that deposits of a rock known as pegmatite could yield “a variety of commodities,” including lithium.

Particularly in Australia companies do mine pegmatite for lithium, but digging and blasting that hard rock out of the ground and breaking it down into usable lithium is expensive, at least compared with lithium production from brines. In certain geologically anomalous spots around the world, there are large salt flats that are saturated with water rich in lithium and other minerals. Extracting lithium from the right kind of salt flat is a cheap and low-impact matter of pumping lithium-rich water from the flat into a series of evaporation ponds, where it bakes in the sun until it is concentrated into an oily yellow solution of 6 percent lithium. Currently, two of the three largest lithium producers in the world get their supply from a single salt flat in northern Chile, the Salar de Atacama. Across the border in Bolivia is the much larger Salar de Uyuni, which is loaded with lithium but which, for political and technical reasons, is still at least a few years from sending lithium to the market.

The penultimate paragraph of the Times story suggested that Afghanistan might have one dry salt lake richer than either of these. And that’s a major point that never appeared in a public USGS report.

Neither the Pentagon nor the USGS will elaborate on the mention in the Times story of a salt-lake lithium source. In an otherwise candid conversation, Jack Medlin of the USGS declined to provide any more details on the subject. Major Shawn Turner, a Pentagon spokesperson, said he had nothing to add.

According to Jack Shroder, a geologist at the University of Nebraska-Omaha’s Center for Afghanistan Studies, a high-altitude plain that’s about a 70-mile drive northwest of the city of Ghazni known as the Dasht-i-Nawar is the obvious candidate for the mysterious Afghan mother lode. Shroder said he didn’t know for certain that this was the spot, but “if the lithium source is in a dry lake and it is near Ghazni, then it is probably the place.” (An alternative, he said, is another dry lake farther to the south called Ab-i-Istada.)

The salt flats of the “Lithium Triangle”—the high desert region where Chile, Argentina and Bolivia intersect which is currently home to the most productive lithium sources in the world—and the Dasht-i-Nawar have several uncanny similarities. They are all arid to semi-arid high-altitude salt flats where flamingos like to breed; that’s the superficial part. They all sit in high-altitude contact zones between tectonic plates, zones where ancient volcanism left behind mineral-rich igneous rocks. Most important, all three are basins surrounded by old volcanoes. (Shroder says that the Dasht-i-Nawar is what remains of the crater of a stratovolcano that erupted 2.2 million years ago.) Over the millennia, as the ice and snow melts off the surrounding mountains and volcanoes every year and seeps down to the basin below, that water leaches minerals from the volcanic rock it encounters along the way and deposits them at the bottom of the basin. In time, the water in the center of the basin grows richer in minerals like potassium, magnesium, boron and lithium.

At the second annual Lithium Supply and Markets conference in January, Afghanistan didn’t come up once in two days of presentations by mining-company executives, geologists and industry analysts. At the next such conference, it will probably be mentioned frequently as a curiosity, because it’s unlikely that Afghan lithium will have any effect on the market for decades. Mining companies aren’t necessarily scared of sketchy countries—I’ve seen North Korea mentioned as a new frontier in minerals exploration in mining trade publications—but at the moment, lithium is cheap (the market leader, SQM, cut its lithium carbonate prices by 20 percent last year) and widely available (at the moment, SQM is actually pumping excess lithium back into the Salar de Atacama because the company harvests more lithium as a by-product of potassium production than it can find a market for). There’s no reason to go lithium prospecting in a war zone.

“As far as Afghanistan is concerned, who cares?” Jon Hykawy, a mining analyst with Byron Capital Markets in Toronto, wrote in an e-mail. “I am not going to be the one leading a team into Taliban territory to try and process lithium.” He drew an analogy between Afghanistan and Colombia. Colombia has potentially excellent oil reserves, just like neighboring Venezuela, but “there has been a low-grade civil war going on in Colombia for the last couple of decades. No one is crazy enough to try and get oil out of the ground in Colombia, and no one is going to go try and get lithium out of the ground in Afghanistan until the thugs are out of the government and the Taliban stop killing anything that moves that is not allied with them.”

Companies don’t like risk and lack of security, and Afghanistan, well—“it will be probably the worst place to go to,” says Gal Luft, the executive director of the energy-focused D.C. think tank the Institute for the Analysis of Global Security.” Security concerns aside, Luft points out that it took years for Chile to build the rail and road infrastructure that gets its huge copper mines running, and before Afghanistan can become a serious mining country, it will need the same infrastructure.

The most likely candidate to build that infrastructure is probably the country that seems most interested in securing Afghan mineral rights, despite the war: China. Last year, using a comprehensive package of humanitarian aid and (allegedly) bribes, a state-run mining company won the rights to the Aynak copper mine south of Kabul. Today the Chinese (the distinction between industry and the government is blurry) are fighting for rights to mine the Hajiguk Pass north of Kabul, home to 1.8 billion metric tons of iron ore—the largest iron deposit in Asia. Shroder says it’s likely that a Chinese firm could win the rights to Hajiguk, build the roads and railway necessary to ship iron ore south to the the Pakistani port of Gwadar (which Chinese concerns also built), and years from now use that existing, paid-for infrastructure to start extracting the lithium from a source like the Dasht-i-Nawar, which is about 100 miles to the south of Hajiguk.

Say this scenario actually happens. Would it have any practical effect on the price or availability of lithium? Not anytime soon. “I don’t think it has a lot of implication for the market in the first half of the 21st century,” Luft says. “This is a story for the 22nd century.”

What the story does now is help show that it is absurd to start talking about an impending shortage of a mineral that the mining industry really only started taking seriously after the spread of lithium-ion batteries in laptops and cell phones in the 1990s. When the Afghanistan news broke, a friend at a mining-industry publication confessed to never having heard of Afghanistan as a potential lithium source. But he also said he wasn’t surprised, because lithium is not rare. What other countries have high-altitude salt lakes that we’ve never paid attention to? As Luft says, “I wouldn’t be surprised if half a dozen other places get thrown around as the 'Saudi Arabia of lithium’” in the years ahead.

MetalCell was designed with militaries in mind; on the modern battlefield, soldiers rely on a growing array of electronics to execute their missions, but when operating in remote areas or cut off from support, those devices can run out of juice at inopportune moments. But MetalCell can sit in the back of a Humvee, in a remote bunker, or in a locker at a forward operating base for years, waiting to power up electrical devices in a pinch.

The rugged little boxes are similar to the so-called Baghdad batteries dating to the early centuries A.D. that some researchers believe were the first voltage-creating devices. Fitted with magnesium plates inside, the MetalCell can be charged up with nothing more than the addition of saltwater. The sodium in the salt reacts with the magnesium to create a dose of low-voltage power that can power up laptop, a flashlight, night vision specs, etc. when no other source is available. The output can keep a laptop humming for more than four hours and can be recharged with fresh saltwater until the magnesium begins to deteriorate.

Soldiers can pool salt from their Meals, Ready-to-Eat (MREs) to create the a proper sodium solution, but failing that, soldiers could also charge up the MetalCell with their urine (and given the blandness of MREs, they might opt to). That's an energy-rich resource a grunt can always lay his hands on.

[National Defense]

The new micro-supercapacitors have at least double the energy storage density of the best supercapacitors

Batteries can store electrical energy in chemical reactants and typically have higher energy storage densities than supercapacitors. But supercapacitors simply store energy as electrical charge and can endure a charge-discharge cycle millions of times, compared to just several thousand cycles for batteries.

"We have known for some time that supercapacitors are faster and longer-lasting alternatives to conventional batteries, so we decided to see if it would be possible to incorporate them into microelectronic devices and if there would be any advantage to doing so," said Yury Gogotsi, a materials engineer at Drexel University in Philadelphia.

Gogotsi worked with John Chmiola, a chemist at the Lawrence Berkeley National Laboratory. They etched electrodes made of monolithic carbon film into a conducting substrate of titanium carbide, and created micro-supercapacitors with an energy storage density at least twice as much as existing supercapacitors.

That suggests micro-supercapacitors can more efficiently store energy within ever-smaller physical spaces. By directly integrating the supercapacitors with the devices they power, researchers can boost the density of microelectronic devices and allow for more functionality, less complexity and enhanced redundancy.

The almost infinite cycle life of micro-supercapacitors would make them ideal for capturing and storing energy from renewable resources, and for on-chip operations to make electronic devices longer lasting, according to Chmiola.

More short-term applications would likely combine micro-supercapacitors with micro-batteries for the most possible energy storage. But the researchers eventually hope to boost super-capacitor storage to levels closer to batteries, and hold onto the supercapacitor edge regarding charge-discharge cycles. The future of micromachines looks bright indeed -- and we can think of a micro drone or two which could use more juice while doing recon.

[via ScienceDaily]

The battery consists of two large silos filled with crushed rock. Electricity generated by the turbine heats and pressurizes argon gas and feeds it into the first silo. The gravel is heated to more than 900 degrees as the hot, pressurized argon passes through, though by the time the argon leaves the chamber it has cooled to ambient temperature.

The argon is then fed into the second silo where it returns to normal atmospheric pressure, initiating a cooling effect that chills the gas and rock to -256 degrees. Thus, the electricity is stored as a temperature difference between the two chambers. If the wind ceases to blow, the process is reversed, feeding the cold gas back into silo number one, powering a generator as it makes the transition back to hot from cold.

The process isn't a perfect closed energy loop, but Isentropic claims a complete trip through the cycle retains up to 80 percent of the original electricity. Even better, gravel is cheap; the cost per kilowatt-hour falls somewhere between $10 and $55, depending on the costs of other materials. Isentropic also claims the batteries are highly durable; according to the company's founder, a 164-foot tall silo with an equal diameter would retain half its energy even if left untouched for three years.

All that sounds pretty good, but Isentropic has yet to fully prove out the idea. The vast temperature differences generated by the argon sound quite drastic, and the director of the UK Energy Research Centre points out, gravel isn't the ideal material to have inside of machine with moving parts. As such, Isentropic is designing a pilot plant that could store 16 megawatt-hours in two silos just 23 feet tall by 23 feet in diameter. That's enough to cover a pretty big neighborhood during a long, windless stretch. The company is also in talks with an unnamed utility to build a larger demonstration facility.

[Guardian, Isentropic]

The new battery simply consists of tanks filled with three liquid layers kept at 1,292 degrees F (700 degrees C). Molten magnesium sits on top, and antimony sits on the bottom. The middle layer consists of a compound mixture of the two outer layers.

Charging the battery with electricity breaks down the middle layer, and thus enlarges the upper and lower layers, while discharging reverses the process, in a chemical reaction that releases electrons to provide power. Once running, the battery also creates enough self-sustaining heat to keep everything deliciously molten.

A battery as large as a shipping container could deliver a megawatt of electricity, or enough to power about 10,000 100-watt light bulbs for several hours. Its cheaper material costs compared to lithium make it a more cost-effective candidate for scaling up the power grid.

Some utility companies and cities have already turned to sodium sulfur batteries as backup power that can ease reliance on the aging transmission grid -- the Texas town of Presidio recently charged up the largest battery of this type in the U.S. But the molten metal battery technology could provide part of a newer energy infrastructure that supports a growing variety of renewable energy sources.

[via New Scientist]

The sodium sulfur battery is the largest of its type

The huge battery began charging up this week and can store up to four megawatts of power for up to eight hours. It represents the first NaS battery in Texas and the biggest in the U.S., and has already earned the local nickname of BOB (big-old battery).

Before BOB's arrival, the Texas town had an agreement with the Mexican government that allowed it to transfer the town's electrical load over to Mexico -- but that took time and left people without power for a certain period.

Similar room-sized sodium sulfur (NaS) batteries have already found growing use among U.S. utility companies that want to put off expensive upgrades for the power grid or building new transmission lines. USA Today notes that the batteries, built by NGK Insulators of Japan, store energy and can help ease blackouts for cities.

Electric Transmission Texas helped put the battery project together for around $25 million. But the utility has also agreed to build a second 60-mile transmission line to Presidio for about $44 million by 2012.

Such a battery could also serve as a test bed for utility companies to see how the devices can help with energy storage regarding renewable energy, such as wind power or solar power. That sounds good to us, as long as utility companies don't simply lean on the batteries as a technological crutch to avoid giving the power grid its much-needed makeover.

[via NPR]