2010 Mercedes Benz SLS AMG E-Cell

Mercedes-AMG is accepting the challenges of motoring of the future: the SLS AMG E-CELL is evidence of the state-of-the-art development of an exciting super sports car featuring a zero-emission high-tech drive. Boasting a power output of 392 kW and 880 Nm of torque, the technology vehicle from AMG is able to offer exceptional performance. The gullwing with electric drive is part of the company strategy entitled “AMG Performance 2015″ which aims to continually reduce fuel consumption and emissions.

With the SLS AMG E-CELL, Mercedes-AMG is providing a glimpse of its latest development project – a powerful and locally emission-free super sports car. Finished in fluorescent “AMG lumilectric magno” paint, the gullwing offers the prospect of a possible small series production run and at the same time reflects the innovative strength and development competence of the AMG performance brand.

“We take social responsibility very seriously and with the SLS AMG E-CELL we are demonstrating a further milestone in our “AMG Performance 2015″ strategy. It is our goal to continually reduce the fuel consumption and emissions of new models in the coming years, while at the same time enhancing the core brand value of performance”, explains Ola Källenius, chairman of the board (from 1 July 2010) of Mercedes-AMG GmbH. With the SLS AMG E-CELL, the performance brand of Mercedes-Benz is launching a totally innovative drive solution for super sports cars and as such is among the pioneers in this market segment.

The ground-breaking drive system of the technology vehicle boasts some outstanding features: powerful traction is provided by four synchronous electric motors with a combined peak output of 392 kW and a maximum torque of 880 Nm. The four compact electric motors each achieve a maximum rpm of 12,000/rpm and are positioned near to the wheels. As a result, compared with wheel-hub motors the unsprung masses are substantially reduced. One transmission per axle transmits the power.

Acceleration from zero to 100 km/h in 4 seconds

When it comes to dynamics, the electrically-powered SLS AMG makes a statement: the gullwing model accelerates from zero to 100 km/h in 4 seconds – which almost puts it on the same high level as the SLS AMG with 6.3-litre V8 engine developing 420 kW (571 hp), which can accelerate to 100 km/h in 3.8 seconds.

Further exciting touches are provided courtesy of the agile accelerator response and the straight-line performance: unlike the combustion engine, torque build-up with an electric motor is instantaneous – maximum torque is available virtually from a standstill. The spontaneous torque build-up and confident power delivery – which does not suffer from any interruption of tractive power – are combined with engine running characteristics which are totally free of vibration. Four motors, four wheels: the intelligent and permanent all-wheel drive of the electric SLS guarantees driving dynamics at the highest level, while at the same time providing the best possible active safety. Perfect traction is therefore ensured for all four driven wheels, whatever the weather conditions.

This very special gullwing is therefore able to “electrify” the driver with a completely unique, effortlessly superior and emotional super sports car driving sensation – and this is just at the prototype stage. In brief: the SLS AMG E-CELL is a true AMG too.

SLS AMG E-CELL
Max Output	392 kW
Torque	880 Nm
0-100 km/h	4 seconds
Rated capacity	40 Ah (at 400 V)
Energy content	3 x 16 kWh = 48 kWh

High-performance electronic control as well as effective cooling of all components

A high-performance electronic control system converts the direct current from the high-voltage battery into three-phase alternating current which is required for the synchronous motors and regulates the energy flow for all operating conditions. Two low-temperature cooling circuits ensure that the four electric motors and the power electronics are maintained at an even operating temperature.
A separate low-temperature circuit is responsible for cooling the high-voltage lithium-ion battery. In low external temperatures, the battery is quickly brought up to operating temperature with the aid of an electric heating element. This helps to preserve the overall service life of the battery. In extremely high external temperatures, the cooling circuit for the battery can be additionally boosted with the aid of the air conditioning system.

Optimum weight distribution and low centre of gravity

The purely electric drive system was factored into the equation as early as the concept phase when the gullwing model was being developed. It is ideally packaged for the integration of the high-performance, zero-emission technology: by way of example, the four electric motors and the two transmissions can be positioned as close to the four wheels as possible and very low down in the vehicle. The same applies to the modular high-current battery, whose modules are located in front of the firewall, in the centre tunnel and behind the seats. Advantages of this solution include the vehicle’s low centre of gravity and balanced weight distribution – ideal conditions for optimum handling, which the electrically-powered SLS AMG shares with its petrol-driven sister model.

The installation of the drive components required no changes whatsoever to the gullwing model’s weight-optimised aluminium spaceframe. And there were just as few constraints when it came to maintaining the excellent level of passive safety and high degree of long-distance comfort that are hallmarks of Mercedes cars.

New front axle design with pushrod damper struts

The additional front-wheel drive called for a newly designed front axle: unlike the series production vehicle with AMG V8 engine, which has a double wishbone axle, the SLS AMG E-CELL features an independent multilink suspension with pushrod damper struts. This is because the vertically-arranged damper struts in the series SLS had to make way for the additional drive shafts. As is usual in a wide variety of racing vehicles, horizontal damper struts are now used, which are operated via separate push rods and transfer levers.

Thanks to this sophisticated front-axle design, which has already been tried and tested in the world of motor sport, the agility and driving dynamics of the electrically-powered SLS AMG attain the same high levels as the V8 variant. Another distinguishing feature is the speed-sensitive power steering with rack-and-pinion steering gear: the power assistance is implemented electrohydraulically rather than just hydraulically.

AMG ceramic composite brakes for perfect deceleration

The technology vehicle is slowed with the aid of AMG ceramic composite brakes, available as an optional extra for the series production model, which boast extremely short stopping distances, a precise actuation point and outstanding fade resistance, even in extreme operating conditions. The over-sized discs – measuring 402 x 39 mm at the front and 360 x 32 mm at the rear – are made of carbon fibre-strengthened ceramic, feature an integral design all round and are connected to an aluminium bowl in a radially floating arrangement.

The ceramic brake discs are 40 percent lighter in weight than the conventional, grey cast iron brake discs. The reduction in unsprung masses not only improves handling dynamics and agility, but also ride comfort and tyre grip. The lower rotating masses at the front axle also ensure a more direct steering response – which is particularly noticeable when taking motorway bends at high speed. The ABS and ESP® systems have been adapted to match the special application spectrum of the permanent all-wheel drive.

Full-LED headlamps and automatically extending front splitter

The purist, exciting design of the technology vehicle boasts a number of minor yet extremely effective modifications. At the front, the dynamically shaped full-LED headlamps with integrated daytime driving lights immediately catch the eye: they help to optimise the vehicle’s energy efficiency, since they require less power compared with regular bi-xenon light systems. The wider radiator grille also has a new look, and now comes with transverse slats instead of a diamond-pattern grille. The air outlet openings on the bonnet and the vehicle sides have also been modified for enhanced aerodynamics. All trim and detachable parts, which are finished in chrome or silver shadow on the standard SLS AMG, are now finished in matt black.

The front apron has not only been brought further forward, but also helps to guarantee an optimised airflow in the area of the underbody. This improves air resistance while reducing downforce. An extendable front splitter enhances this effect: in parallel with the automatic rear spoiler, it extends downwards by seven centimetres at speeds above 120 km/h and helps to further accelerate the air which travels beneath the car. When it reaches the area of the rear axle, the air enters the rear diffusor which, due to the lack of an exhaust system, features a steeper angle, thus increasing downforce at the rear axle and in turn further enhancing the aerodynamic balance. The vehicle’s AMG 10-spoke light-alloy wheels featuring a new, smooth-surfaced design are fitted with 265/35 R 19 (front) and 295/30 R 20 (rear) tyres.

Interior with new display instruments for electric drive

The transformation from petrol to electric super sports car also called for some specific changes to the interior. As a result, the AMG instrument cluster and centre console in particular both feature a new design. The new AMG instrument cluster provides information on speed, charge status of the battery and the estimated range. The newly designed centre console now houses a 25 cm touchscreen, which driver and passenger can use to conveniently operate all of the audio, climate and navigation functions, and also obtain information on the flow of power from the four electric motors.

The AMG Drive Unit, which is angled towards the driver, houses buttons for starting the motor, and the ESP® functions, the AMG memory function and the extendable front splitter and rear spoiler. Using three new buttons, the driver can switch simply between P, R and D. The park setting is also enabled automatically by switching the electric motors off.

The interior appointments are dominated by high-quality nappa leather in a black/white colour combination – it has been used not only on the sports seats, the performance leather/alcantara steering wheel and the door linings, but also on the broad centre tunnel which runs towards the back of the vehicle between the seats.

(Source:Mercedes Benz Press Release)

2010 Mercedes-Benz SLS AMG GT3

Automotive fascination combined with spectacular racing car design – the new Mercedes-Benz SLS AMG GT3. This racing version of the gullwing model was designed as customer sports car for competing in race series according to the near-series FIA GT3 rulebook. Outstanding handling dynamics are ensured by uncompromising lightweight construction and specific modifications to the suspension, brakes and aerodynamics. This very special gullwing model will deliver its debut performance on the racetrack in 2011.

The purist design and breathtaking contours of this gullwing model are effectively emphasised by specific modifications to the bodywork. The new components made mainly from carbon-fibre are an unmistakable testimony to the outstanding racetrack performance and extensive aerodynamic development work.

At the front the GT3 racing car has a new front apron with larger air intakes: the wide aperture below the characteristic radiator grille with a large Mercedes star and a wing-shaped transverse fin supplies the engine oil cooler and brake discs with cooling air. The two air intakes below the vertically arranged bi-xenon headlamps have the same function. Downforce at the front axle is provided by four externally mounted “flics” and the carbon-fibre front splitter: this blends into the smooth underbody cladding which ends with the rear diffuser.

The bonnet has a central aperture to dissipate the engine heat. The hot air is vented in the wheel arches from side vents in the front wings. Particularly lightweight polycarbonate is used to glaze the side and rear windows, and this is also available for the windscreen.

The front and rear wings have been widened to make space for the large racing tyres. With a width of 1990 millimetres, the body of the GT3 is a good 50 millimetres wider than that of the standard SLS AMG. The new side skirts have apertures for cooling the rear brakes. The smooth underbody is visible at the lower edges of the side skirts. The standardised filler pipe for the fast-refuel system is accommodated in the B-pillar. The 120-litre fuel tank is centrally located behind the driver.

Wide rear apron of carbon-fibre

Viewed from the rear, the SLS AMG GT3 impresses with its sheer width. The boot lid is surmounted by a wide carbon-fibre rear aerofoil, which has multiple adjustments and allows a perfect setup for the type of racetrack concerned. The new rear apron features two apertures designed to vent the rear wheel arches. The carbon-fibre rear diffuser is another eye-catching feature: as an extension to the smooth underbody, it gradually rises in the rear axle area and generates a downforce thanks to its shape. The overall aerodynamic concept of the SLS AMG GT3 was refined and finalised in extensive wind tunnel and racetrack tests.

The black exhaust tailpipes emit a thrilling and very characteristic AMG eight-cylinder sound. The rain light prescribed by the rulebook is integrated into the boot lid – it must remain permanently switched on if the weather conditions are poor.

Near-series AMG 6.3-litre V8 engine

As prescribed by the FIA GT3 rules, the AMG 6.3-litre V8 engine is practically identical to that in the standard model. Thanks to its lower weight, the GT3 will easily better the already outstanding acceleration of the standard model – 3.8 seconds from zero to 100 km/h; depending on the final drive ratio, the top speed will exceed 300 km/h.

The AMG 6.3-litre V8 engine also has a dry sump lubrication system in the racing model. Using vacuum and pressure pumps, as well as an external oil tank, makes it possible to dispense with a conventional sump. This technology ensures reliable engine lubrication even under the high lateral acceleration forces encountered on the racetrack.

Dry sump lubrication also allows a low installed position for the V8 engine – one of the key technological highlights of the SLS AMG. Installing the eight-cylinder engine in the lowest possible position behind the front axle as a front-mid engine, and combining it with the transmission in a transaxle arrangement, produces a very favourable weight distribution.

Six-speed racing transmission with sequential gear-changes

Unlike in the standard model, power in the SLS AMG GT3 is transferred by a six-speed racing transmission with sequential gear-changes. Thanks to its compact construction, this race-tested transmission has advantages in terms of packaging – after all, the GT3 version has a smaller ground clearance than the standard model. The driver shifts the gears using two shift paddles on the steering wheel. The transmission is mounted directly on the rear axle, and connected to the V8 engine via a flexurally and torsionally rigid torque tube. This has decisive advantages with respect to handling dynamics, as this sophisticated solution enables the entire powertrain to be configured with far less free play. In conjunction with the traction control sysem, a multi-disc locking differential integrated into the transmission ensures outstanding acceleration. A drive shaft rotates at the engine speed within this torque tube. As in the standard model, and also the Mercedes-Benz C-Class DTM racing cars, the shaft is made from carbon-fibre.

The vehicle concept of the SLS AMG is predestined for top-class racetrack performance, with a long wheelbase, a low centre of gravity and a wide track. Its strengths include precise over/understeer characteristics, first-class agility, low inertia during fast changes of direction and high physical limits when cornering.

Very few modifications were required for perfect racetrack performance: the lowered, lightweight aluminium suspension with double wishbones all-round has the ideal kinematics. Multiple adjustments allow the best possible adaptation to the relevant racetrack characteristics and prevailing weather conditions. Not only the spring and damper setups, but also the track width and camber, the suspension height and the stabilisers at the front and rear axles can be adjusted.

The rack-and-pinion steering system with speed-sensitive servo assistance is basically the same as in the standard SLS AMG. The more direct steering ratio makes for even more agile handling on the racetrack.

AMG motor sports braking system with composite technology

The AMG motor sports braking system ensures extremely short braking distances, outstanding fade-resistance and great sensitivity: race-tested composite technology is used for all the brake discs. In this system, the grey cast-iron discs are mounted on an aluminium bowl via stainless steel connections in a radially and axially floating arrangement. This sopisticated technology allows perfect heat conduction, and therefore reliable fade-resistance. The SLS AMG GT3 also features precisely configured cooling ducts: apertures in the front apron and in front of the rear wheels supply the brake discs with cool air when on the move. All four brake discs are ventilated, grooved and perforated. Six-piston fixed calipers at the front and four-piston fixed calipers at the rear in anthracite with a white AMG logo allow generous brake lining surfaces. An anti-lock braking system with a special racing configuration is standard. For space reasons, the AMG high-performance ceramic composite braking system optionally available for the standard model is not compatible with the 18-inch wheels prescribed by the FIA rulebook.

The size 12 x 18-inch (front) and 13 x 18-inch (rear) AMG light-alloy wheels with central locking are shod with racing tyres in size 287 x 682 mm (front) and 315 x 708 mm (rear). Depending on the conditions, untreaded slicks, intermediates or rain tyres are used. The classic multi-spoke design assists ventilation of the braking system. Rapid pitstops and wheel-changes are assured by the pneumatic jacking system integrated into the underbody: four pneumatic jacks lift the GT3 racing car by around 190 millimetres to allow very rapid wheel-changes by the pit crew.

Interior with racing bucket seat and racing steering wheel

Opening the gullwing doors of the SLS AMG GT3 reveals a functional interior with a racing car atmosphere. The driver is seated in a racing bucket seat, his safety assured by a six-point seat belt and the HANS system (Head and Neck Support), which fixes his helmet in a defined position during an accident to minimise the risk of injury. Additional safety is provided by the steel rollover cage, which also serves to reinforce the aluminium spaceframe.

A racing steering wheel with a diameter of 330 millimetres allows perfect vehicle control. Thanks to the open upper section of the rim, the driver always has a clear view of the central display. This keeps him informed about all the relevant parameters such as speed, engine rpm, operating temperatures, lap times and the selected gear. The steering wheel also has a quick-locking feature which allows much easier access and egress. Switches on the steering wheel boss enable the driver to activate additional functions such as the radio link to the pits, headlamp flasher or the drink function. Further controls are mounted on the centre console, for example the start/stop function for the AMG V8 engine, the traction control system, reverse gear and – if the worst should happen – the integrated fire extinguisher system. The brake balance adjustment control is mounted on the tunnel of the torque tube.

The near-series specification of the GT3 version is reflected in the dashboard, whose powerfully arching wing section gives an impression of width. Strikingly integrated into the dashboard, the air vents galvanised in “Silver Shadow” have adjustable, cruciform nozzles reminiscent of an aircraft’s jet engines.

Deliveries of customer vehicles will commence in spring 2011

The new SLS AMG GT3 was developed to comply with the international FIA GT3 race rules, and is entitled to take part in all GT3 race series – which of course includes the popular 24-hour race in Spa-Francorchamps (Belgium) or the Nürburgring. Interested customers are able to order the GT3 from autumn 2010, and delivery will take place in time for the start of the 2011 racing season. Homologation will be completed in March 2011.

(Source:Daimler Press Release)