2007 Tesla Roadster

A new kind of car from a Silicon Valley start-up

It has lithium-ion batteries and comes with a charging cable, just like your cellphone. Unlike your phone, however, it can go from zero to 100 kilometers per hour in less than 4 seconds, pinning you against the back of your seat like a fighter pilot. And it’ll do it with a lot less noise—and for US $70 000 less—than a Ferrari F430.

Created by Tesla Motors, a Silicon Valley start-up in San Carlos, the Tesla Roadster is powered by 6831 mass-market lithium-ion batteries and costs about $100 000. Want one? Fine, just put down $75 000 now and wait until summer 2008 to take delivery.

The Tesla is based on a design by England’s Lotus, renowned for its small, light sports cars. Tesla's engineers worked closely with Lotus to adapt its Elise platform to electric power, along with substantial reworking to accept Tesla's Lithium-ion battery and distinct styling (in carbon-fiber rather than fiberglass). They also extended the car's wheelbase. The car weighs just 1100 kilograms (2425 pounds), nearly a third of that battery weight. With its 185-kilowatt motor, it has a top speed of 210 km/h (130 mph).

As with any pure electric car, the key parameters are the batteries’ recharge time, energy density, and useful life. The point of reference is the only recent electric vehicle from a major manufacturer, the late, lamented General Motors EV1. When the EV1 was introduced in 1996, it ran on lead-acid batteries, had a maximum range of 95 km (60 miles), and took up to 12 hours to recharge. The Tesla uses the same lithium-ion batteries found in laptops and digital cameras. Their energy density can be as high as 160 watt-hours per kilogram—or at least four times that of typical lead-acid cells. So the Tesla has a 400-km range and, best of all, it can recharge in as little as 3.5 hours.

Unresolved at the moment is the issue of battery life. Laptop batteries usually don’t last the 10 years required of major automotive components. And Tesla has indicated it expects its battery pack’s power to degrade up to 30 percent in as few as five years or 200 000 km. More than a dozen companies are trying to develop lithium-ion batteries in sizes and packages suitable for automotive use. When one of them succeeds, the tactic of lashing together many small cells bolstered by instrumentation to monitor and accommodate the power or thermal variances among them probably will end.

Tesla Motors is hardly the only new EV maker these days, though its $40 million in venture funding puts it at the top of the list. Globally, more than two dozen companies are offering electric cars of all different sorts, from drab econo-boxes to supercars like the Tesla Roadster.

Meanwhile, as of January, Tesla had sold more than 250 cars—a tidy sum at $100 000 each. The first cars are supposed to be delivered in September, if crash-test analyses and other U.S. government-certification requirements go smoothly.

Tesla also has plans for a second car, a sporty four-seat sedan code-named White Star. The company hopes to launch that car by 2010, at a price of $50 000. To do so, it has set up an engineering center in Rochester Hills, Mich., and plans to staff it with more than 50 engineers.

Honda FCX / Concept

Can a fuel-cell car be sexy?

If you want one, you’ll have to wait until 2018 at least, Honda says. But still, its latest "FCX concept car takes hydrogen fuel-cell power trains into a new, sleeker realm. It’s a radical, stylish departure from the previous FCX’s upright, slab-sided hatchback design.

Honda revealed its new FCX this past summer, around the same time GM previewed its Chevrolet Sequel fuel-cell vehicle. But the two cars couldn’t be more different. The Sequel is a conventionally attractive sport-utility vehicle, but the FCX is a low, four-door, five-passenger sedan. It would look right at home on the Autobahn, although its maximum speed of 160 kilometers per hour (100 miles per hour) wouldn’t win it many friends in the left lane.

It is powered by the company’s third-generation fuel cell, which is 20 percent smaller and 30 percent lighter, and at 100 kilowatts, 14 kilowatts more powerful. The new V (for vertical) Flow stack stands upright, and can be packaged in what used to be called a “transmission tunnel” between the seats, lowering the center of gravity and doing away with the characteristic tall, upright design of most previous fuel-cell vehicles.

More important, the design helps eliminate one of the biggest obstacles to mainstream use of fuel-cell cars: the cost and complexity of the systems needed to let the cells withstand subfreezing temperatures when they’re not running. Water is a by-product of the reaction that liberates electrical energy in a fuel cell. But any water remaining in the cells’ stack, where the reaction occurs, would cause damage if it froze there. In Honda’s vertical-flow design, gravity helps drain that water—improving performance and reducing the power needed to pump the stack dry every time the car is turned off. According to Honda, the system works so well that the car can start at temperatures as low as –20 °C.

With a smaller and lighter 95-kW drive motor, the new FCX’s complete power system is 180 kilograms lighter and almost 40 percent smaller than its predecessor’s. Hydrogen is stored in a 171-liter tank at a pressure of 350 atmospheres, giving the car a range of 435 km (270 miles), Honda says.

Honda plans to put the car into very limited production in Japan next year. Still, it’s a step forward: virtually all fuel-cell cars built so far have gone into carefully maintained and sheltered fleets at utility companies, for example. But Honda says it is considering leasing the cars for US $600 or $700 a month to interested private citizens, to get real-world feedback on how the new FCX drives, rides, and performs.