Set to get its first public airing in production guise at the Paris motor show in September, the R8 e-tron shares its appearance with the standard R8. But the changes made to accommodate its two rear electric motors and lithium ion battery pack as well as a series of lightweight construction measures and altered suspension are sufficient enough that Audi’s outgoing head of development, Michael Dick, describes it as being all-new.
“Don’t let the styling fool you. The construction, drivetrain and chassis have been completely altered. It is essentially an all-new car – from the ground up, says Dick.
At the heart of the R8 e-tron, which Audi will place into limited production at the end of 2012, is a pair of mid-rear mounted synchronous electric motors – one for each wheel. Developing a total of 376bhp and sturdy 605lb ft of torque, they draw energy from a 550kg lithium ion battery mounted within the middle tunnel and provide direct drive to the rear wheels. In normal every day driving the hi-tech drivetrain is said to provide an overall range over 200km.
Electricity used to charge the batteries is recuperated on the run via an energy recovery system that works in combination with the R8 e-tron’s carbon ceramic brake system as well as a plug-in arrangement via a socket mounted in the new Audi’s left-hand side bodywork.
To off-set the added weight brought on by the battery pack, Audi has also provided its new zero emission supercar with a reworked spaceframe structure that incorporates both aluminium and carbon fibre as well as new composite plastic components within the suspension and a reworked interior with carbon fibre backed seats among other changes. In production guise it is claimed to weigh 220kg more than the R8 V8 at 1780kg.
The R8 e-tron is among a raft of new performance orientated electric cars inspired by the Telsa roadster and set to enter the market within the next 12 months. Its keenest rival is the Mercedes-Benz SLS E-cell, which packs a quartet of electric motors – one for each wheel – and is claimed to develop and even more prodigious 525bhp and 649lb ft of torque.