Audi E-Tron scoop

The silent supercar revolution is almost upon us, with Audi's e-tron spied testing in Germany just weeks before Mercedes-Benz's AMG division launches its electric SLS.

Both the German powerhouses are in a race to dominate the electric supercar world, and this prototype, snapped testing not far from home in Bavaria, is as revealing for what it doesn't have as for what it does.

For starters, there are no air intakes anywhere on the e-tron prototype and it has even blanked off the traditional front and side air intakes of the V8 and V10 R8s on which it is based.

First shown at last year's Frankfurt Motor Show, the e-tron, Audi claimed the production version would have a total of 4500Nm of torque from the instant the driver stepped on the throttle -- or about six times what the most powerful petrol-engined cars have on offer now.

It achieves that, and 230kW (313hp) of power, by having an in-board electric motor driving each wheel and a liquid-cooled, mid-mounted 53kW/hr Lithium-Ion battery. While Audi claimed the e-tron would have a typical range of just under 250km, the concept car used enough torque to blast to 100km/h in 4.8 seconds.

Yet there are other missing details off the spied prototype, including the rumoured electric hub motors, which will keep the weight down to the targeted 1600kg. And, of course, exhaust pipes.

The prototype clearly carries over the concept's carbon-ceramic brakes, and sources at Audi have confirmed they are brake-by-wire units that regenerate huge amounts of power back to the battery.

Audi sources confirm the R8-based e-tron will still be limited to 200km/h when it goes on sale next year.

The following press information from Audi reveals more about the e-tron:

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