The Audi R8 e-tron has just been spotted running some hot laps on the vaunted Nurburgring track in Germany. The test mule features large 'e-tron' decals on the sides and windshield and is a testament to the German's hard work on their electric lineup.The R8 e-tron, at first sight on the track, seems a bit like a contradiction - identical R8 coupe styling with a very aggressive look and a deceptively quiet noise. For a car without exhaust pipes, it shouldn't surprise, but given our gross familiarity with the supercar it just seems a bit...off.Also different on the Audi R8 e-tron is that the rear window which usually shows off a V8, or if you are lucky, the V10, is covered up. The hood features a big hole for the cooling of the batteries. A new grille is also visible, a sign that the ‘normal' R8's facelift meant for later this year is also well on its way.The Audi R8 e-tron is expected to hit the showrooms in 2013 in limited numbers.