* Audi launches revamped R8 e-tron at Geneva show
* Daimler CEO says investigating high-end electric cars
* Audi still treading carefully in electric cars - analysts (Recasts with Daimler, analyst comments)
By Andreas Cremer and Edward Taylor
BERLIN/GENEVA, March 4 (Reuters) - German carmakers are shifting their focus towards high-end electric vehicles such as the Audi R8 e-tron and away from cheap city cars, in the latest effort to revive environmentally-friendly but unpopular zero-emission vehicles.
At the Geneva auto show, Audi unveiled an emission-free version of its 165,000-euro ($184,619) R8 that can drive 450 kilometres (280 miles) before needing to recharge, which takes less than two hours.
It marks a new departure for Audi, which has agonized over whether to launch a range of electric vehicles.
Battery-powered cars have failed to live up to their initial hype, with drivers put off by the slow rollout of recharging stations, and limited range -- despite generous sales incentives in some markets.
Because the batteries, cabling and cooling systems for electric cars cost more than a conventional combustion engine, electric vehicles have struggled to gain widespread acceptance among price-sensitive customers, particularly if the same model is available cheaper with a more conventional powertrain.
However, U.S. maker Tesla, which produces cars with a price starting at 50,000 pounds ($77,000) has had notable success with electric cars.
A premium price-tag enables the carmaker to install a larger battery which would be uneconomical in a cheap car, giving the vehicle a range of more than 400 kilometres on a single charge. In smaller electric cars, the operating range is limited to around 100 kilometres until costs come down.
In Geneva, Daimler CEO Dieter Zetsche said one of the reasons electric cars had failed to gain traction was because they tended to be in the cheaper vehicle segments.
"As proven by Tesla, there can be a market at the other side of the range as well. If that is a possibility, we are investigating," Zetsche said, hinting the company's luxury Mercedes brand may be working on an electric limousine.
The electric car industry may still gain traction, but it will take time, Zetsche added. "This is an industry where the cycle takes 14 or 21 years to become really strong and relevant," he told reporters.
For electric cars to gain widespread acceptance, the price of batteries needs to fall below $100 per kilowatt hour (kWh), Ulrich Hackenberg, head of research and development at Audi, told Reuters on the sidelines of a Volkswagen event in Geneva. Hackenberg declined to say where battery prices were currently.