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  Electric-Car Fever: Grand Visions at the Geneva Auto Show

Electric-Car Fever Grand Visions at the Geneva Auto Show

By Christian Wüst

Part 2: 'Not Good Enough'

VW's choice of Toshiba came as a surprise to the automotive world. The Tokyo-based company is known for its extremely durable lithium-titanate batteries. But with an energy density of little more than 60 watt hours per kilogram, this type of battery would be too heavy for use in cars. Daimler supplier Li-Tec is focusing on a lithium-manganese-nickel-cobalt combination, which already achieves an energy density of close to 150 watt hours per kilogram.

Toyota, the automaker still considered the world leader in electric motors, is also enthusiastic about the performance of Li-Tec's battery. Toyota uses Li-Tec batteries in Formula 1 racing, where the use of electric auxiliary motors was recently approved.

Japanese carmakers Honda and Toyota were well ahead of the curve when it came to mass production of hybrid powertrains consisting of gasoline engines and electric motors. Today the two companies already have a full decade of experience under their belts, which may be the reason they seem hesitant to switch to completely electric motors.

"The batteries available today are not good enough," explains Honda research chief Masaaki Kato. The total electrification of the automobile, says Kato, is "not something we have to work on in a hurry."

The experts at Toyota voice similar skepticism, though they are more willing to talk about how to move development along. In fact, Toyota is doing so much that all its competitors should be alarmed.

The world's biggest carmaker has an enormous R&D center for electric powertrains at its Nagoya headquarters, where more than 2,000 employees are examining the potential for electric vehicles. Mercedes, by comparison, has 400 engineers working in the new field.

Toyota has in-house departments for developing all facets of electric powertrains. The company is careful not to leave anything up to potentially incapable suppliers, in particular the development of batteries.

For the past six years, Toyota has produced its own lithium batteries and tested them in various environments, such as in the automatic start-stop systems in conventional cars. The batteries at first were produced at a rate of 100 a month, but a new automated production line will increase production by a factor of 100.

The head of this one-of-a-kind research facility is Koei Saga, one of the key figures behind Toyota's hybrid success. He speaks slowly, with the serenity of someone who has no need to make promises he cannot keep.

"We see no breakthrough in battery technology," says Saga. He's cautious in what he says about the ambitions of other manufacturers. He has "no comment" on a pure electric car based on the Mitsubishi model, although the tone of these two words suggests that he does not take the project seriously.

He is more interested in the General Motors serial hybrid, an electric car with an auxiliary engine. "We put a lot of thought into that," says Saga, explaining why the principle was eventually discarded.

A serial hybrid is only a good solution if the internal combustion engine is used very rarely, according to Saga. It is undisputed that in gasoline mode, a car with a direct mechanical transmission operates far more efficiently than one with an engine that merely generates electricity to drive the electric motor. This concept, says Saga, can be feasible and marketable only with more powerful and less expensive batteries.

For now, Toyota will stick to a more modest concept and develop its existing Prius hybrid into a "plug-in hybrid," which still drives primarily on gasoline but, for shorter distances, relies on an electric motor that can be recharged in a standard electric outlet.

A lithium battery, charged with about five to eight times as much energy as a battery in the ordinary Prius hybrid, will let the plug-in Prius travel some 20 kilometers in city traffic on electricity alone. The internal combustion engine takes over after that.

Production of the plug-in Prius will begin this year, in small numbers that will step up gradually. Saga predicts world sales of the plug-in Prius to reach about 15,000 in 2012. This, he says, is the "biggest step possible" at the moment.

Toyota prefers to leave the production of show cars with no market prospects to other carmakers. BMW is launching a test in the United States of 500 electric Minis it says will have a range of more than 200 kilometers (125 miles). The batteries take up the entire trunk space and rear seat area, and they have also proven to be unexpectedly thirsty during charging.

In fact, the batteries sucked up so much current that circuits became overloaded in many places.

With reporting by Jürgen Pander. Translated from the German by Christopher Sultan.