Detroit 2010: Lighter, Smaller Audi E-Tron

Audi has pulled a fast one at Detroit and managed to keep its Second E-Tron electric car concept a complete secret until its unveiling.

The first Audi e-tron concept car debuted at the Frankfurt Motor Show and impressed with its mix of slightly-smaller-but-sleeker-than-an-R8 looks and electric performance – in both senses of the word.

Size-wise
But just as the original e-tron was slightly smaller than the R8, with which it shared a similar aluminium spaceframe construction, the new e-tron concept is slightly smaller than the TT, measuring 3,930mm x 1,780mm x 1,220mm.

Powerplant
E-tron two is a strict two-seater, as the area behind the seats is occupied by 399kg of lithium ion batteries. These provide power to the rear wheels, which are driven by two electric motors. Charging takes 11 hours by household socket, or two hours with a quick charger.

Stats and facts
The motors generate 204hp and 2,650Nm of torque, propelling the car from 0-62mph in 5.9 seconds and on to a limited top speed of 124mph. Audi reckons a range of 155 miles too.

Understeer killer
Also included is an electronic version of Audi’s torque vectoring system which sends volts to the outer wheel when cornering. Coupled to the concept’s 40:60 weight distribution that should mean, theoretically at least, it’ll be fun to drive.

Brake-by-wire
The concept features an electro-mechanical brake system. There’s a conventional hydraulic system on the front axle, but the rear brakes are electrically actuated. This brake-by-wire system means the electric motors can be used more efficiently to gradually slow the car and thus recuperate energy as the car slows. The rear brakes only come on when you need to slow down quickly.

Design time
The E-tron manages to look both modern and retro. The newness is mostly down to the front end’s adaptive LED headlights, which automatically adjust to the road conditions, weather and information from the satnav, while the classic proportions, stubby tail and multi-spoke 19-inch wheels are more old school. We like the fact that the battery cooling ducts are hidden in the C-pillars and open Lamborghini-Murcielago-style when it gets hot too.