2015 Audi R8 e-tron prototype first drive

A good deal has changed since we last drove the Audi R8 e-tron, the car maker's all-electric sports car.

Having come close to limited production during the latter half of 2013, only to be cancelled at the final hour due to concerns over its less than dazzling range, the first generation of low-slung two-seater has now been extensively re-engineered under the watchful eye of Audi research and development boss, Ulrich Hackenberg.

Among the key developments, it now has new electric motors and a significantly larger battery that is claimed to more than double the distance it can travel between recharging 

Like all existing R8 e-tron developmental prototypes on the Audi test fleet right now, the example driven here continues to be based around the first-generation R8.

There are subtle exterior design changes including active air ducts that open at a predetermined speed, a flat underbody and an altered rear valance that help it to slip through the air with greater aerodynamic efficiency than petrol-engined versions of Ingolstadt’s performance flagship.  

Beneath the familiar bodywork, however, lurks the new electric driveline technology showcased on the new second-generation R8 e-tron wheeled out at last week’s Geneva motor show, including a patented welding process for the 52 battery modules.

Hackenberg says this was pioneered on the Volkswagen XL1 and is claimed to vastly improve the thermal properties of the 7488 individual lithium-ion cells mounted behind the cabin for greater energy saving.  

Adopting the same layout as the earlier Audi R8 e-tron prototype we drove back in 2013, the new production version is driven by a pair of electric motors that act exclusively on the rear wheels.

However, while the original layout has been retained, each individual driveline component has been upgraded in a bid to provide the latest incarnation of Audi’s electric sports car with added performance and a far more practical range. 

The new electric motors, produced at parent company Volkswagen’s Kassel manufacturing plant in Germany, deliver a combined 456bhp (340kW), or some 80bhp (60kW) more than before. Torque has also increased by 74lb ft to a new peak of 679lb ft – all of which is unleashed the very moment your foot brushes the heavily sprung throttle.

To put this into some sort of perspective, the four-wheel-drive Tesla Model S P85D possesses 690bhp and 516lb ft. However, while the R8 e-tron is claimed to weigh 1840kg, the P85D tips the scales at a significantly more portly 2100kg.  

Drive from the e-tron's electric motors is channelled through a fixed-ratio gearbox. This has been modified to include a coasting function that sees the new Audi freewheel with minimal mechanical drag when you come off the throttle for extended periods – a function Hackenberg believes should have been included on the car from the outset.   

Whereas the earlier R8 e-tron drew its electric energy from a 48.6kWh lithium ion battery, the new one gets a much larger 91.0kWh unit. The cells it uses also operate at a higher 3.6 amperes compared with 3.2 amperes previously, giving the e-tron greater discharge ability for better accelerative performance.