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Posts Tagged ‘lithium-ion batteries’

Now researchers at Rice University have combined the two, packing an entire lithium-ion battery into a single nanowire. The developers say it’s as small as such a device can possibly get.

Researchers led by Rice professor Pulickel Ajayan built a hybrid energy storage device, which serves as a battery and a supercapacitor. The first version sandwiched an electrolyte between a nickel/tin anode and a cathode made of a polymer called polyaniline. The cathode also served as a supercapacitor, storing lithium ions in bulk, as this writeup by Rice University explains. The prototype proved that lithium ions would move through the electrolyte and into the cathode.

Then Ajayan and colleagues incorporated this structure into a single nanowire, through a complicated process of etching and chemical washing. The goal is to make nanowires with ultra-thin separation between electrodes, so the device can remain as small as possible.

The completed wire-batteries are about 50 microns tall, which is roughly the diameter of a human hair, according to Rice.

For now, they can only charge and discharge about 20 times before they die, but researchers are trying to optimize them to last longer. The research is published in the journal ACS Nano Letters.

[via PhysOrg]

At the Lithium Supply and Markets conference in Toronto, analysts make clear that until 2020 there will literally be more than enough of the element to go around

The noise about “Peak Lithium”—the idea that not enough economically extractable lithium exists in the world to support a large-scale switch to cars powered by lithium-based batteries—has quieted significantly in the past year, but I still sometimes get asked: Are we going to run out of this stuff?

Not any time soon. In fact, as a noted market analyst made clear this morning, so many companies are developing so many lithium deposits around the world that many of them will probably go out of business, because they’re on track to dramatically oversupply the world with lithium.

Currently, most of the world’s lithium comes from a handful of companies, most notably SQM, Chemetall, and FMC; they extract lithium from high-altitude salt flats in northern Chile and Argentina. Those companies have long insisted that they have access to so much lithium, and that they could expand supply so easily and quickly, that the dozens of independent lithium prospectors who hope to capitalize on arrival of the lithium-ion-powered electrified automobile are doomed.

This morning, Edward R. Anderson, president of the independent consulting firm TRU Group, told the assembled group of international lithium prospectors much the same thing. According to TRU’s latest study of the lithium market—an update of an earlier study TRU conducted for Mitsubishi, which the group presented at the first Lithium Supply and Markets Conference in Santiago, Chile in January 2009—the world will soon be overloaded with lithium producers. Together, these producers will end up flooding the market; there will be too much lithium to go around, and all but the strongest companies will probably fail.

We at PopSci are not concerned with lithium as an investment, of course: We’re interested in what news like this means for the people who buy raw lithium, make it into batteries, and then put those batteries into electrified vehicles. For the junior mining companies in the audience, Anderson's presentation might have been bracing. For battery companies and carmakers, however, it means that there is no reason to be concerned about the availability or price of lithium, even as batteries—particularly electric-vehicle batteries—quickly come to consume the bulk of the world’s lithium supply.

To be sure, Anderson didn't even mention the words "Peak Lithium"—his was a business presentation focused on the next ten years. He's also far from the first person to argue that lithium is plentiful. (See Keith Evans's blog.) But Anderson’s presentation this morning was a current and forceful argument that one vastly overhyped barrier to the near- and mid-term adoption of electrified vehicles simply doesn’t exist.

All this said, it’s worth keeping in mind that the majority of all this abundant lithium is extracted by three companies from a relatively tiny section of South American desert. There’s still a case to be made that diversifying the lithium supply is a good thing. Later in the conference we’ll hear Western Lithium, a company that controls a potentially massive lithium mine in northern Nevada, make that case.

Bottled Lightning is a blog series by Seth Fletcher, Senior Associate Editor at PopSci and author of Bottled Lightning: Superbatteries, Electric Cars, and the New Lithium Economy, to be published in May 2011 by Hill & Wang/Farrar, Straus & Giroux. The book is about lithium, the rechargeable lithium battery, and the technological transformations it has helped (or will help) make possible—the wireless revolution; the burgeoning electric-car revival; the coming spread of clean energy. Seth also posts off-the-cuff observations on these and other subjects on Twitter.

Findings could lead to better batteries

So next time you throw out (and hopefully recycle) a pair of lithium batteries, show some respect for the deformations it suffered while powering your camera.

The itty-bitty battery provided an unprecedented view of the charging process, as scientists watched it writhe and swell as ions flow in. The work, published today in the journal Science, illuminates how rechargeable batteries die and could lead to better, longer-lasting alternatives.

You can only recharge and reuse lithium batteries for so long before they lose capacity and fail, because the continual charging cycle damages the electrodes. The new nanometer-scale images show just how this happens — it turns out the electrodes fatten and stretch as lithium ions flow inside, like a snake stretching to fit its swallowed prey. The ions also change the electrode’s physical characteristics.

Over time, all these contortions damage the electrode material by introducing tiny defects, according to researchers at the Department of Energy.

Lithium batteries are ubiquitous in everything from cell phones to hybrid cars, but they are limited by low energy and power densities. Hoping to improve these qualities, researchers wanted to find out exactly how they work. Scientists at Sandia National Laboratory formed a tiny battery under a transmission electron microscope. It consisted of a single 100 nm diameter tin oxide nanowire anode, a bulk lithium cobalt oxide cathode, and an ionic liquid electrolyte. In one of the videos, the lithium ions look like juice being sucked through a nanowire straw.

Battery researchers do use nanomaterials as anodes, but they use them in bulk rather than individually, according to Sandia Labs researcher Jianyu Huang. It’s like “looking at a forest and trying to understand the behavior of an individual tree,” he said in a statement. By contrast, his method allowed atomic-scale observations of individual trees.

Huang and colleagues were able to measure the wire’s tortuous twisting, noting that it nearly doubled in length during charging — a fairly surprising result. Most battery developers had believed batteries swell across their diameters, not longitudinally, so a better understanding of these stretchy processes could help avoid short circuits.

The work is a testimony to the power of direct observation, said MIT materials scientist Yet-Ming Chiang in a perspective article accompanying the study.

“The results should stimulate others to consider analogous experiments and mechanisms in other storage materials, and should contribute to the design of nanoscale electrodes that fully exploit the potential of ultrahigh-capacity storage materials,” Chiang wrote.

Watch the battery's growing pains below.

Jane Chang, an engineer at the University of California-Los Angeles, is designing a tiny solid electrolyte that allows charge to flow between two nanoscale electrodes. Eventually, the wee batteries could be used to power a host of micro and nanodevices.

The special electrolyte is basically just a series of nanowires coated with conductive material. Chang is using painstakingly slow atomic layer deposition to spray minuscule amounts of lithium aluminosilicate onto the nanowires. The solid compound allows current to flow within a battery. The nanowires are designed to have a high surface-to-volume ratio, making them more efficient.

“We're trying to achieve the same power densities, the same energy densities, as traditional lithium ion batteries, but we need to make the footprint much smaller,” Chang says.

Nanoscale electrodes are being designed in other labs, but so far, no one has built a complete working nano-battery, according to UCLA.

If they work, they could be more effective, and perhaps less prone to scary malfunction, than nuclear microbatteries or virus-powered batteries. The batteries could be useful for powering devices for medical diagnostics and treatment, among other technologies.

Chang announced her latest results Tuesday at the AVS 57th International Symposium & Exhibition in Albuquerque.

The batteries were fabricated by materials scientists at Stanford by depositing a thin film of carbon nanotubes followed by another thin film of metal-containing lithium compound on top of the nanotube layer. These thin bilayer films are layered onto both sides of a piece of ordinary paper, which serves as both the structural support of the battery as well as the electrode separator. The lithium serves as electrodes, while the nanotube layers are current collectors.

The result is a working battery just 300 micrometers thick – that’s 300 millionths of a meter – that is flexible, super-thin, and more energy dense than other thin-bodied batteries. It’s also durable; over a 300-cycle recharge test, performance remained satisfactory. It’s also fairly easy to fabricate, making it far more commercially viable than other methods of downsizing battery technology.

Such batteries aren’t ideal for every application, but they could be extremely useful in future incarnations of smart packaging, RFID sensing, and electronic paper products.

[Chemical & Engineering News]

Here’s a list of cleantech news we’re tracking today:

China has become the top country for cleantech investment, outstripping the U.S., according to a report from Ernst & Young. China’s renewable energy investment dollars outdoes the U.S. nearly two to one, Green Chip Stocks reports, and installed wind power capcity in the U.S. has dropped to its lowest in three years. Germany, India, the U.K., Portugal and Spain also topped the list. Read the full report here.

Large-scale solar plant builder BrightSource could go public within three years, GigaOm reports, citing a report from Next Up research. (The report isn’t available online.) The story notes that an IPO would still be a few years off, thanks to the reluctance of venture capitalists to invest in solar — one example being Solyndra’s axed public offering plans. But BrightSource seems to be headed in the IPO direction: it recently won a federal loan guarantee and raised $439 million in its last round of financing.

GM, Itochu charge up battery startup Sakti3 with $4.2 million, with GM reportedly proffering $3.2 million of that total. Sakti3 is working on a smaller, cheaper lithium-ion battery that could extend the range of electric vehicles currently on the market. A GM spokeswoman says it’s years away from commercialization, but the technology could eventually wind up in GM’s trucks and cars.

Come launch time in December, the Nissan Leaf will have an edge over the Chevrolet Volt thanks to sweeter state rebate policies – states like California and Tennessee are giving Leaf buyers additional incentives, but shutting out the Volt. We’ve reported before that the Volt got the short shrift from the state of California, which wouldn’t extend single drivers of the Volt access to the HOV lane (though that perk was granted to Prius owners), and also won’t give it the $5,000 rebate it’s giving the Nissan Leaf, since the Volt will have tailpipe emissions (the gas tank kicks in after the electric battery’s 40-mile range runs out), whereas the Leaf is all-electric.

Fire and ice: SunPower and Ice Energy will team up to build a pilot energy storage project, reportedly for Target. The system will use SunPower’s rooftop solar panels to generate power. When the sun wanes, Ice Energy’s ice-based storage system will take over, using power stored from the day to cool the building and cutting peak-time energy costs.

Audi may have blundered in naming its electric cars e-Tron – the French word, étron, essentially means “dung,” says Green Car Reports. If that’s the case, then it’s even more unfortunate that e-Tron is slated to present at the Paris Motor Show next month.

Tags: battery, China, e-Tron, electric cars, electric vehicles, Leaf, lithium-ion batteries, solar energy, Volt

Companies: Audi, BrightSource, Chevrolet, Ernst & Young, GM, Ice Energy, Itochu, Next Up, Nissan, Sakti3, Solyndra, SunPower, Target

GM Ventures, the venture-capital arm of General Motors, announced today it has teamed up with Itochu Technology Ventures to invest $4.2 million into Sakti3, a lithium-ion battery developer.

Sakti3, a spin-off from the University of Michigan, is working on battery cells that could be smaller, cheaper and more effective than what’s currently on the market – potentially resulting in batteries that could extend its range of electric cars. The company’s technology uses solids instead of the standard liquid electrolyte and electrodes.

“The technology will eventually make it into GM batteries/vehicles, but it’s years away from commercial applications,” said GM spokeswoman Allison Ackels. “When the technology becomes commercially viable, it could be in future GM cars and trucks.”

GM, which it set to release the Chevrolet Volt electric hybrid later this year, reportedly invested $3.2 million.

The reborn General Motors opened its venture-capital branch in June to fund advanced transportation projects. With its backing and that of Japanese conglomerate Itochu (which recently invested in video platform Ooyala and game startup Tonchidot), Sakti3 should be able to speed the commercialization of its batteries.

This is the second announcement from GM Ventures, which said last month it would invest $5 million in Bright Automotive, which makes a hybrid van.

Range and the reliability of batteries are big question marks in the electric car market. While consumers have tax incentives to purchase an electric car – the Nissan Leaf, Coda sedan and Chevrolet Volt all debut at the end of this year – questions remain about the range of these cars and the reliability of the batteries, which are expensive to replace. The Leaf, for example, goes about 100 miles on a single charge, but could perform worse in extremely cold or hot weather.

It’s also not clear how long the batteries last, though Nissan and Chevrolet both extended an 8-year, 100,000-mile warranty to the Leaf and Volt, respectively.

Sakti3 is led by Ann Marie Sastry (pictured above, with a Volt), a University of Michigan professor recently profiled in the New York Times. Sakti3’s  investors include Khosla and Beringea.

Tags: batteries, Coda sedan, electric cars, electric vehicles, Leaf, lithium-ion batteries, Volt

Companies: Beringea, Chevrolet, Coda, GM, Khosla, Nissan, Sakti3