Audi e-tron showcar – take two at the NAIAS
Earlier this week Audi has used the NAIAS 2010 to display another version of the “uncompromising purist compact sports car” which uses all-electric drive. Compared to the an electric vehicle displayed at the 2009 Frankfurt Motor Show, the e-tron 1 showcar, this one looks more polished set of ideas in a better packaging. It's shorter, lower and narrower than the e-tron 1 and brings the glimpse of the intelligent multi-purpose LED headlights, WiFi and satnav sync feature among other things.
The Audi e-tron has a very low profile at just 122 centimeters at summit of a pure coupe roofline. In less than 4 meters, it is also a very compact coupe, shorter than Audi TT and its weight is kept on minimum for a car with heavy batteries and electric motors. At around 1,350 kilos it weights one hundred kgs less than the 2009 Audi TT RS Coupé.
Two of its high-torque electric motors driving the rear wheels provide the combined output of 150 kW (204 hp) and 2,650 Nm, enough to launch the coupe with ASF-design aluminum body from 0 to 100 km/h in just 5.9 seconds. For example, 2009 Audi TT RS Coupé with 250 kW (340 hp) and 450 Nm goes from 0 to 100 km/h in just 4.6 seconds. E-tron is capable of fast accelerations from 60 to 120 km/h in a mere 5.1 seconds. The top speed is limited to 200 km/h, as the amount of energy required by the electric motors increases disproportionately to speed.
Similar to what the sport differential does in conventional cars, torque vectoring – the targeted acceleration of individual wheels – makes the Audi e-tron even more dynamic while simultaneously enhancing driving safety. Audi says that e-tron’s “torque vectoring” is the key to its precision handling and excellent traction. Understeer and oversteer can be corrected by not only targeted activation of the brakes, but also by precise increases in power lasting just a few milliseconds.
Thanks also to its low weight, short wheelbase and perfect weight distribution, the Audi e-tron has all the drivability of a go-kart – agile, good on bends and neutral right up to the very high handling limit. The Audi concept car rolls on 19-inch wheels of 35-spoke design. 235/35 tires up front and 255/35 tires at the rear provide excellent grip enhanced by the specifically designed profile.
Lithium-ion batteries, located behind the passenger compartment and ahead of the rear axle, make an effective energy content of 45 kilowatt-hours available, and help to achieve 40:60 weight distribution. The range in the NECD combined cycle is approximately 250 kilometers. The batteries are charged with household current (230V, 16A) via a cable and a plug. The charging time when the battery is empty is around 11 hours. Provided with heavy current (400V, 32A) cuts this to around just two hours. During braking, the alternator converts the kinetic energy into electrical energy, which it then feeds into the on-board electrical system.
All light units use LED technology. The headlights are the core of a fully automatic light assistance system that reacts flexibly to any situation. The new technology recognizes weather conditions and adapts the illumination to rain or fog. The technology at the heart of the light assistance system is a camera that works together with a fast computer to detect oncoming traffic, recognize lanes and measure visibilities, such as in the event of fog.
If there is oncoming traffic, the high beams are turned off in the corresponding section of the illumination field. The cornering light system analyzes data from the navigation system and illuminates corners before the driver steers into them. Instead of fog lamps e-tron intelligently varies the low beams instead; in fog, for example, it produces a wider, more horizontal illumination field, thus significantly reducing the glare from the car’s own lights.
Inside, racing-inspired lightweight bucket seats combine excellent lateral support with comfort. The slim dash has a curve that extends laterally into the door panels. With no need to allow for a transmission, shifter and cardan tunnel, the designers took advantage of the opportunity to create a particularly slim and lightweight center tunnel and convex, arching center console.
The Audi e-tron’s cockpit is also oriented toward the driver. Instead of the classic instrument cluster, the concept car is the first Audi to be equipped with a large built-in central display with integrated MMI functions. It is flanked by two round dials.
The MMI is controlled via a scroll pad with a touch-sensitive surface on the steering wheel. The steering wheel itself is clearly flattened off at both the top and bottom.
A smartphone that can be integrated into the front section of the center console interfaces between the vehicle, the driver and external information sources. The driver can use a suitably equipped conventional smartphone as a car phone, address database, navigation system and video player. At the same time they can also use it as an operating unit for many specific on-board systems in the Audi e-tron.
The system also provides a security function for the owner; within the range of the WLAN it can constantly monitor the current status of the vehicle, for instance whether all windows and doors are closed.
Unlike a combustion engine, the electric drive system generally does not produce enough waste heat to effectively heat the interior. Audi uses the heat pump which is commonly used in residential Air Conditioners and represents an efficient means for heating the car. A high-efficiency climate control system is used to cool the interior. It works together with the thermal management system to also control the temperature of the high-voltage battery. This is because the battery, power electronics and electric motors must be kept at their respective ideal operating temperatures to achieve optimal performance and range.
As soon as the vehicle is connected to a charging station the vehicle is preconditioned as appropriate by the thermal management and other associated systems. In cold conditions the drive system is preheated, and in hot conditions it is cooled.