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Etats - Unis: The Lithium-Ion Car
Altair Nanotechnologies plans to road test an advanced electric vehicle prototype.
By Kevin Bullis
    Advances in lithium-ion battery technology over the last few years have experts and enthusiasts alike wondering if the new batteries may soon make high-performance electric vehicles widely available. Now one company, Altair Nanotechnologies of Reno, NV, has announced plans to start testing its new batteries in prototype electric vehicles, with road tests scheduled to begin by year-end.
    The company says its new electrode materials allow higher bursts of power, longer battery life, and more available energy storage capacity -- and far quicker "fill-up" -- than previous lithium-ion batteries. The goal: an electric car that performs as well as a conventional car. "The user experience will be similar, except the vehicle is quieter and it's environmentally greener" says Alan Gotcher, the company's CEO.
    Altairnano plans to incorporate batteries that use their new lithium-ion electrode material into a prototype electric vehicle, in cooperation with Boshart Engineering of Ontario, CA. Gotcher says the batteries use a safe, stable structure that increases their lifetime by preventing the electrodes from expanding and contracting as the ions move in and out -- a principle reason for the eventual death of conventional lithium-ion batteries.
    The batteries can also handle big bursts of power, which occur in both fast charging and quick acceleration. Also, Gotcher says an electric vehicle using their batteries could charge in about the time it takes to fill a tank of gas and buy a cup of coffee and snack -- six to eight minutes.
    This efficiency and an expected range of 200-250 miles could make such an electric car more appealing to consumers than GM's now-discontinued EV-1, for example, which took six to eight hours to charge and had a range of only 75-130 miles, depending on conditions. The extended range of the new batteries, which have a total storage capacity similar to today's nickel metal-hydride batteries, is possible because they can be discharged more deeply while maintaining a constant voltage, increasing the usable energy storage capacity, Gotcher says.
    Gotcher says the new battery materials can be produced for about the same cost as conventional lithium-ion materials, but will have two to three times the lifespan of today's batteries. He says it's too early to speculate on the price of a production vehicle using the batteries.
    The performance figures seem promising to Ron Freund, chairman of the non-profit Electric Auto Association based in Los Altos Hills, CA. "Sounds great," he says, "but the proof in the pudding is how they work in a vehicle, so it's useful that they are going to create a vehicle." He hopes the company won't stop there, since data from just one prototype can be misleading -- the real question, he says, is whether such vehicles can be made with consistent performance from vehicle to vehicle.
    In the past, electric vehicles powered by lead-acid or nickel-metal hydride batteries, such as GMs EV-1 and Toyota's RAV4-EV, have sold poorly, leading the automakers to discontinue them.		 Today consumers are limited to so-called "neighborhood" electric vehicles, which have to stay off highways, and some limited production full-speed models, such as the Tango, famously driven by the actor George Clooney, and some pricey high-performance sports cars. Many hobbyists also opt to convert hybrids and conventional cars to electric cars themselves.
    The new electric sports cars use conventional lithium-ion batteries for the same reason they're now used in laptop computers: they store a lot of energy in a small, light package. But several factors have kept these batteries out of widespread use in vehicles. One is cost -- the Venturi Fetish sports car, for example, sells for over $500,000. The batteries are also tricky to operate safely in the large quantities needed in vehicles -- overheating or damage can cause them to catch fire or explode (as led to last year's Apple PowerBook battery recall). These batteries also have a short lifespan, losing their ability to hold a charge well over time, as anyone who's owned a laptop for a few years knows.
    New lithium-ion battery materials, however, may change all this. Safer chemistries have recently allowed manufacturers such as Milwaukee Electric Tool in Brookfield, WI, and DeWalt Industrial Tool of Baltimore MD, to start using lithium-ion batteries in abuse-prone power tools. The new materials could also extend the batteries' lifetime, reduce their cost, and improve their performance.
    In part, these advances have been due to nanotechnology. Lithium-ion batteries create a current by shuttling ions between the electrodes as the battery charges and discharges. The added surface area of nanoscale particles on electrode materials helps the ions escape, freeing more of them to travel and provide bursts of power or quick recharging.
    Gotcher says that, in addition to testing their prototype for safety and performance, they plan to submit the batteries to the U.S. Department of Energy for standardized tests of battery safety and performance, including lifetime.
    If the batteries do hold up to tests, widespread adoption of such a vehicle still may depend on other factors, such as gas stations installing power stations for quick charging, which will require more than a standard outlet. Gotcher says these stations could benefit from batteries, which would make it possible to draw energy from the power grid at off peak hours, saving on electricity costs, and then deliver it quickly when driver's need it.
    Altairnano is hardly the only company with promising new battery materials. "There are dozens of capable advanced battery manufacturers," says Dave Goldstein, president of the Electric Vehicle Association of Greater Washington, DC and president of Program Development Associates, which does electric vehicle and advanced battery consulting. "Lithium-ion batteries are showing a tremendous amount of progress. There's still work to be done to bring the lithium-ion battery to the level that automobile manufacturers expect. They're looking for a more significant guarantee that these batteries will last at least 10 years. But the newer batteries have shown significant promise."