Saturday, February 09, 2008

I Sing the Auto Electric

Inside Plug-in Car Tech's Race to Production

Big automakers and promising startups say electric vehicles are coming as soon as next year, but there's a lot of work to be done—by scientists—before lithium-ion batteries are ready for mainstream hybrids.

Flashy concepts and expensive, limited edition sports cars have made the plug-in car market an attractive one. Now major car companies from Detroit to Japan are outsourcing for chemistry and spending big bucks in-house to put low-cost, high-power packs of lithium-ion in larger production fleets by 2010 or 2011.

The future of American motoring will be—at least in part—battery-powered. Now, it’s becoming increasingly clear that the lithium-ion pack is what will get us there. Almost every top-tier carmaker has announced plans to use the technology, but they haven’t exactly said when we might see roadworthy li-ion-powered vehicles. The consensus is that they’ll probably start to appear in the 2010 to 2012 time frame—though no one’s promising anything.

Even though lithium-ion already runs everything from laptops to screwdrivers, the reality remains that only a handful of smaller companies actually make these electric cars for production (or soon will). It all comes down to that battery.

Issue No. 1: Battery Chemistry

Sounds simple, right? Like other batteries, those that use lithium work by shuttling ions (electrically charged atoms or groups of atoms) between their electrodes. The most widely used have a positive electrode made from cobalt or manganese oxide and a negative electrode made from graphite. The electrolyte (the material through which the ions pass from one electrode to the other) is a lithium-based gel or polymer. These types of batteries are mainly used in laptops, and are not well-suited for the automotive environment. The problem is that the chemistry isn’t stable enough, so batteries suffer from overheating—and that can have an explosive effect.

The most promising electrode chemical makeups, then, involve nano-engineered materials like phosphates of iron, lithium-titanate spinel and, most recently, bundles of silicon nanowires. Some battery companies have battery recipes that are ready for series production now, at least for mild hybrids. Milwaukee-based Johnson Controls/Saft, has been touting research it calls NCA, which has been approved for mild and full conversions by OEM powerhouses.

Meanwhile, Toyota appears to be close, if not locked into its chemistry of plug-in hybrids. Recently, Toyota’s president Katsuaki Watanabe said they would be accelerating development to have a large-scale (an estimated several-hundred-to-a-thousand-vehicle) test fleet in service by 2010 or earlier.

Even so, there doesn’t seem to be a clear winner here or a one-size-fits-all solution. And it’s going to take a lot more practical application to figure what works over the long run. “It’ll take companies like AC Propulsion and Tesla to put some products on the market to see what works and what doesn’t,” says Tom Gage, president and CEO of AC Propulsion. “Right now, the market is too small for the top tiers to produce anything.”

Issue No. 2: System Integration

This is where one of the major bottlenecks lies, because simply choosing a battery isn’t enough. It must work seamlessly within the vehicle, communicating with all major systems and working in unison with the vehicle’s drive system. Needless to say, synching everything up doesn’t happen overnight, though Gage insists the timetable “wouldn’t be different for any new tech being put into a car. It takes about three to six years for this process to happen.”

Johnson Controls/Saft may be further along—to a degree. Its team will supply the li-ion battery pack for Mercedes-Benz’s S 300 diesel hybrid in 2010, which will be a mild hybrid sold only in Europe (a gas-hybrid version will hit the U.S in late 2009). “We’ve cleared many of the battery management hurdles,” Andrew says

Issue No. 3: Production

After overcoming the first two hurdles, the industry would then need to figure out where all of these batteries are actually going to come from. “They need to be produced in high quantities and with a high level of quality control,” Gray says.

A source inside Toyota says that getting the lithium-ion packs into mass production—not the chemistry—is the company’s biggest hurdle. Late last year, Toyota engineers admitted that producing cells en masse while upholding the company’s usual quality was proving very difficult.

Still, Toyota is close to making production work, and they will be opening a new lithium-ion battery production line at the joint-venture Toyota/Panasonic plant soon.

Meanwhile, Johnson Controls/Saft broke ground on a new lithium-ion line at their Nersac, France, battery facility. This plant will produce the Mercedes batteries as well as packs for other possible European hybrids that have yet to be announced. However, it would be unlikely that this facility would produce packs for vehicles built in North America.


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