For those of you who like fast, expensive, all-electric sports cars, next year will be big.

The Audi R8 e-tron will launch first, but it will soon be followed by the Mercedes-Benz SLS E-Cell, the all-electric conversion of its expensive gull-wing sports coupe.

Now, Motor Authority has some spy photos of a prototype SLS E-Cell being tested on the fabled Nürburgring race track in Germany.

Aside from a couple of small badges saying "E-Cell" and the lack of exhaust pipes, the electric SLS looks pretty much the same as the gasoline version--which sports a 405-hp, 5.5-liter V-8 engine.

The electric SLS was first announced more than two years ago, aimed at the electric Audi R8 and also perhaps the Tesla Roadster, then still in production and on sale.

The company showed the car in the U.S. at last year's Detroit Auto Show, and provided more technical details.

It uses four electric motors, one per wheel for all-wheel drive (although they're not wheel motors per se), and power output is a prodigious 525 horsepower on tap and 649 pounds-feet of torque from a standstill.

The company claims a 0-to-62-mph time of less than 4 seconds.

Earlier this year, Mercedes-Benz explicitly drew parallels between Formula 1 technology and its electric supercar, including lessons drawn from the Kinetic Energy Recovery System (KERS) technology and such exotic components as carbon-ceramic brakes.

If you want to see what a development version of an electric supercar looks like at speed on the track, check the spy photos at Motor Authority.


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