300,000 Kilometers In A Mercedes Fuel Cell Vehicle

Toyota, Honda and Hyundai are not the only car makers working on fuel cell vehicles. Mercedes-Benz has a fleet of 300 B Class-based fuel cell electric vehicles (FCEVs) that have traveled 5.6 million miles since 2010. Recently, one of those cars drove more than 186,000 miles in normal driving conditions, proving that FCEVs offer long term reliability in the real world.

That accomplishment earned Mercedes a Fuel Cell Innovation Award from a jury composed of economists, scientists and political leaders who said “The test is a step in the direction of series-ready application of the fuel cell drive train.” Mercedes is working closely with Ford and Nissan to develop a common fuel cell drivetrain that will be available in showrooms by 2017.

But before that can happen, the hydrogen infrastructure to refuel FCEVs will need to make enormous strides forward. Nobody is going to buy an FCEV if it can’t be refueled conveniently. Recently, the process was given a boost after standards for hydrogen refueling equipment were established.

Mercedes is aware of the challenge and is aggressively pursuing the build-out of hydrogen transportation and refueling systems. Says Prof. Herbert Kohler, chief environmental officer of Daimler AG.“We have clearly demonstrated that the fuel cell electric drive is ready for the road. The last hurdles we will overcome in intensive cross-industry and cross-border teamwork.”

So, is the hydrogen economy ready for prime time? Right now, most  hydrogen is derived from natural gas. Thanks to the rise in fracking here in America and around the world, natural gas is readily available. But if the purpose of FCEVs is to help the environment and if FCEVs rely on fracking for fuel, is the hydrogen economy a step forward or a step back for our beleaguered global eco-system?

The drive system of the Mercedes-Benz SLS AMG E-CELL: Advanced technology made visible

PRESS RELEASE

With the electric drivetrain system of the SLS AMG E-CELL, Mercedes-AMG GmbH is providing yet another glimpse of its latest development project. The drivetrain has been in development since 2010 as a result of the cooperation between Mercedes-AMG and Mercedes AMG High Performance Powertrains in Brixworth. Four synchronous electric motors located near the wheels, providing a peak output of 392 kW and torque of 880 Nm, help to provide the SLS AMG E-CELL with its exciting driving dynamics. The carbon-fibre transmission tunnel, which also serves as the monocoque housing for the high-voltage battery modules, is structurally integrated into the aluminium body shell and firmly bonded to it. The lightweight fibre composite materials have their origins in the world of Formula 1, among other areas.

A small series-production run of the Mercedes-Benz SLS AMG E-CELL is expected to be launched onto the market in 2013. The powerful and locally emission-free super sports car with electric drive is yet another example of the innovative strength and development competence of the AMG performance brand.

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 rotational speed of 12,000 rpm and are positioned close 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 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 a combustion engine, torque build-up in 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.
The key data at a glance:

SLS AMG E-CELL
Max. output: 392 kW
Torque: 880 Nm
0 - 100 km/h: 4.0 s
Energy content: 3 x 16 kWh = 48 kWh

All-wheel drive with torque vectoring enables completely new levels of freedom
Four wheels, four motors – 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. Optimum traction is therefore ensured, whatever the weather conditions. According to the AMG developers, "torque vectoring" involves the individual control of the electric motors, something which enables completely new levels of freedom to be achieved. Torque vectoring is permanently active and allows for selective distribution of forces for each individual wheel. The intelligent distribution of drive torque greatly benefits driving dynamics, handling, driving safety and ride comfort. Each individual wheel can be electrically driven and electrically braked, depending on the driving conditions, thus helping to optimise the vehicle's cornering properties, reduce the tendency to oversteer/understeer, increase the yaw damping of the basic vehicle, reduce the steering effort and steering angle required, increase traction, and minimise ESP® intervention.

Torque vectoring enables optimum use of the adhesion potential between the tyres and the road surface in all driving conditions, thereby extending the critical limits of the vehicle's driving dynamics.

Advanced technology from Formula 1: high-voltage lithium-ion battery
The SLS AMG E-CELL incorporates a liquid-cooled high-voltage lithium-ion battery featuring a modular design with an energy content of 48 kWh. Its development has made use of advanced technology from the world of Formula 1: the battery is the first result of the co-operation between Mercedes-AMG GmbH in Affalterbach and Mercedes AMG High Performance Powertrains (formerly Mercedes-Benz High Performance Engines). Headquartered in Brixworth, England, the company has been working closely with AMG for a number of years. F1 engine experts have benefited from its extensive expertise with the KERS hybrid concept, which made its debut in the 2009 Formula 1 season. At the Hungarian Grand Prix in 2009, Lewis Hamilton achieved the first historic victory for a Formula 1 vehicle featuring KERS hybrid technology in the form of the Mercedes-Benz KER System.

The high-voltage battery consists of 12 modules each comprising 72 lithium-ion polymer cells. This optimised arrangement of a total of 864 cells has benefits not only in terms of best use of the installation space, but also in terms of performance. The maximum electric load potential of the high-voltage battery is 480 kW, which is an absolute best value in the automotive sector. Another technical feature of this considerable performance is the intelligent parallel circuit of the individual battery modules – this also helps to maximise the safety, reliability and service life of the battery. As in Formula 1, the 400-volt battery is charged by means of targeted recuperation during braking whilst the car is being driven.

High-performance 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.

"AMG Lightweight Performance" design strategy
The trailblazing body shell structure of the SLS AMG E-CELL is part of the ambitious "AMG Lightweight Performance" design strategy. The battery is located within a carbon-fibre monocoque which forms an integral part of the body shell and acts as the gullwing model's "spine". The fibre composite materials have their roots in the world of Formula 1, among other areas. The advantages of carbon-fibre were exploited by the AMG engineers in the design of the monocoque. These include their high strength, which makes it possible to create extremely rigid structures in terms of torsion and bending, excellent crash performance and low weight. CFRP components are up to 50 percent lighter than comparable steel ones, yet retain the same level of stability. Compared with aluminium, the weight saving is still around 30 percent, while the material is considerably thinner. The weight advantages achieved through the carbon-fibre battery monocoque are reflected in the agility of the SLS AMG E-CELL and, in conjunction with the highly innovative wheel-selective four-wheel drive system, ensure true driving enjoyment.

The carbon-fibre battery monocoque is, in addition, conceived as a "zero intrusion cell" in order to meet the very highest expectations in terms of crash safety. It protects the battery modules inside the vehicle from deformation or damage in the event of a crash.

The basis for CFRP construction is provided by fine carbon fibres, ten times thinner than a human hair. A length of this innovative fibre reaching from here to the moon would weigh a mere 25 grams. Between 1000 and 24,000 of these fibres are used to form individual strands. Machines then weave and sew them into fibre mats several layers thick, which can be moulded into three-dimensional shapes. When injected with liquid synthetic resin, this hardens to give the desired structure its final shape and stability.

Through their experience with the SLR, the AMG Black Series vehicles and in motorsport, Mercedes-Benz and AMG have accumulated more than 10 years of expertise in working with carbon-fibre materials. AMG currently makes the propshaft for the SLS AMG, for example, in carbon-fibre. On the SLS Roadster, the supporting structure for the draught-stop is made as standard as a carbon sandwich structure. This component, with extremely short cycle times in an industrially oriented manufacturing process, already demonstrates what will be possible in the future.

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-voltage battery. 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 gullwing model shares with its petrol-driven sister model.

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 multi-link 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 motorsport, the agility and driving dynamics of the SLS AMG E-CELL 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 high-performance ceramic composite brakes, 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.

Mercedes-Benz To Control Smart Car Distribution in the US - Penske Relieved of Duties

Smart ForTwo EV










Mercedes-Benz has agreed to take over Smart car distribution in the United States from Penske Automotive Group, the companies announced today.

Penske launched the European microcar brand, which is owned by Mercedes' parent, Daimler AG, as an independent distributor in 2008. But after a fast start, U.S. sales of the tiny, French-built ForTwo have plummeted.

Distribution rights and management will shift to Mercedes-Benz USA. Negotiations over details, including when the hand-over takes effect, should be completed by July, said Mercedes-Benz USA CEO Ernst Lieb.

The 21 Smart dealerships that do not have Mercedes products will lose the franchise, leaving Smart with 58 U.S. dealers. Four of the 21 dealerships that will lose the Smart franchise belong to publicly traded Penske Automotive.

In addition, a four-door car being developed by Nissan for Smart USA has been canceled.

Smart USA President Jill Lajdziak will remain with Penske Automotive, the nation's second-largest auto retailer. Mercedes-Benz will run Smart as a division, similar to its Sprinter commercial vehicle unit, and will appoint a general manager, Lieb said.

Fuel economy a key

Lieb said an agreement was signed Friday, but financial details have not been hammered out. Mercedes initiated the discussions with Penske in early January at the Detroit auto show, he said.

Penske got off to a roaring start with Smart, selling 24,622 cars in the United States in 2008, as gasoline prices reached record highs. But sales have tumbled in the past two years -- falling 59 percent in 2010 to 5,927. But both parties said Smart's shrinking sales are not prompting the hand-over.

Lieb said Mercedes-Benz wants Smart back for two main reasons:

1. It needs more small-car volume to meet new corporate average fuel economy standards that take effect in the United States in the 2016 model year.

2. Daimler AG integrated Smart into the Mercedes-Benz car unit in September. The United States is the only market where Smart and Mercedes operate separately.

“It has become clear over the last few months that Smart is an integral part of our achieving the fuel economy targets of 2016,” Lieb said.

Smart’s fuel economy numbers are already included in Mercedes’ corporate average. But Mercedes executives believe they can increase Smart’s sales volume, and thus have a greater impact on the company's CAFE ratings.

Penske Automotive will handle termination of the 17 non-Mercedes-Benz dealers as part of the deal.

Penske Automotive CEO Roger Penske said the closings will include the buyback of signs, equipment and cars -- in accordance with the franchise agreement.

Mercedes-Benz could give Smart franchises to other Mercedes-Benz dealers, but Lieb said they would not be required to build stand-alone facilities.

“In most cases a shop-in-shop has proven to be the most economical,” he said. “If you are selling one or two cars, you need consistency in personnel and expenses. It will not work if you have a stand-alone facility.”

Lieb said 300 of Mercedes-Benz' 353 U.S. dealers have upgraded their showrooms to the Autohaus corporate facility program.

“This will be a lot easier than it would have been three years ago,” he said. “The facilities are completely different.”

Project Quattro canceled

Smart dealers in the United States sell the ForTwo and an electric version of the microcar. The brand isn't scheduled to receive a new vehicle for two or three years. That will be a four-door being developed with Renault/Nissan as part of an alliance with Mercedes-Benz.

A separate Nissan-based four-door that has been under development for Smart USA won't happen. That car was due to be launched in late 2011 or early 2012.

“We will stop the project,” Lieb said. “If Smart continued as a free-standing network, they would need a second model to make it viable. By integrating it into Mercedes-Benz, there is no need.”

The Mexican-built car, which had been dubbed Project Quattro, could be canceled at any time according to the agreement with Nissan.

Roger Penske said Mercedes-Benz has the marketing muscle that Smart needs.

“We have launched a brand we can hand off to MB-USA,” he said. “We couldn't give it the muscle that it needed from a marketing standpoint based on the volume.

“This is not a shutdown,” Penske added. “This is nothing compared to a Hummer or a Mercury, this is changing distributorship from a private distributor.”

Lieb said Mercedes-Benz views the buyback as “an opportunity with 353 dealers to drive Smart in a different direction.”

He said Mercedes will interview Smart's 20-plus employees to fill field and technical posts.

Michael Cantanucci, owner of New Country Motor Cars Inc., which has two Mercedes stores in Florida and one in Connecticut, said combining Smart and Mercedes makes sense because of the CAFE requirements.

He said: “The penalties going forward are just too expensive and this is a logical way for us to meet the objective.”

Source: Automotive News

SLS AMG E-CELL Electric Super Sportscar Slated for Production in 2013

SLS AMG E-CELL Click to enlarge.

Mercedes-AMG plans to begin production of the SLS AMG E-CELL electric super sportscar in 2013, said Dr. Dieter Zetsche, Chairman of the Board of Management of Daimler AG during the company’s press conference at the North American International Auto Show. Mercedes first announced development of the electric gull-wing sportscar in July 2009.

The four synchronous electric motors in the SLS AMG E-CELL deliver a combined 525 hp (392 kW) of power and 649 lb-ft (880 N·m) of torque. The four compact electric motors each achieve a maximum rpm of 12,000/rpm and are positioned close to the wheels, substantially reducing unsprung masses compared with wheel-hub motors. One transmission per axle transmits the power.

The race for the best super sportscar with electric drive is on.

—Dieter Zetsche

The SLS AMG E-CELL drive features a liquid-cooled, high-voltage lithium-ion modular battery pack with an energy content of 48 kWh and a capacity of 40 Ah. The maximum electric load potential of the battery, which consists of 324 lithium-ion polymer cells, is 480 kW. One of the technical bases of this performance is the intelligent parallel switching of the individual battery modules, which also helps to maximize the safety, reliability and service life of the battery, according to the company. The 400-volt battery is charged using targeted recuperation during braking.

The incorporation of the electric drive components required no changes whatsoever to car’s weight-optimized aluminum spaceframe. Click to enlarge.

The electric-only drive system was factored into the SLS development process at the concept phase. Its packaging is designed for the integration of the high-performance, zero-emissions technology, enabling the four electric motors and two transmission units to be positioned as close to the four wheels as possible and very low down in the vehicle.

The same applies to the modular high-voltage battery—its component parts are located in front of the firewall, in the center tunnel and behind the seats. Benefits of this solution include the vehicle's low center of gravity and balanced weight distribution—ideal conditions for optimum handling, and something the electric-drive SLS AMG shares with its gasoline sibling.

The additional drive to the front wheels necessitated a new front axle design. Unlike the series production vehicle with the AMG V8 engine, which has double wishbone suspension, the SLS AMG E-CELL features an independent multi-link suspension with pushrod damper struts. This is because the vertically-mounted damper struts in the series-production SLS had to make way for the additional drive shafts. Frequently found in racing cars, the new horizontal damper units are actuated via separate pushrods and transfer levers.

Another distinguishing feature is the speed-sensitive, rack-and-pinion power steering, with the power assistance operated by electro-hydraulics rather than conventional hydraulics.

The braking system on the prototype features AMG ceramic two-piece brakes, available as an optional extra on the series production model. It delivers extremely short stopping distances, a precise actuation point and outstanding fade resistance, even under extreme operating conditions. The generously dimensioned, radially floating rotors measure 15.83 x 1.54 inches at the front and 14.17 x 1.26 inches at the rear and are made of carbon fiber reinforced ceramic composite material connected to aluminum hubs.

The ceramic brake discs are 40% lighter than the conventional, gray cast iron brake discs. This reduction in unsprung mass improves not only handling dynamics and agility, but also ride comfort and grip. The lower rotating masses on the front axle also ensure a more direct steering response—which is especially effective in high-speed cornering. The ABS and ESP systems have been adapted to match the particular operating spectrum of the permanent all-wheel drive.

Source: Green Car Congress

Renault-Nissan Alliance and Daimler AG announce wide-ranging strategic cooperation

PRESS RELEASE:

Cooperation on the next-generation smart fortwo and Renault Twingo, including electric versions, as well as on expanding the smart and Twingo families
* Widespread powertrain sharing and co-development on future projects with applications across passenger cars and light commercial vehicles, specifically:
- The sharing and co-development of diesel and gasoline engines from the Renault-Nissan Alliance; to be used in the new smart and Renault Twingo and to be adapted and modified with Mercedes-Benz characteristics for its new generation of premium compact cars
- The sharing of gasoline and diesel engines coming from Daimler to Infiniti, the luxury division of Nissan Motor Company, and providing the opportunity for further collaboration
- The sharing of a Renault-Nissan Alliance diesel engine and transmission for the Mercedes-Benz Vito

* Collaboration in the field of light commercial vehicles
* One-time cross-shareholding amounting to 3.1% of each partner’s equity capital
* Additional synergies encompassing selective common purchasing opportunities, exchange of operational benchmarks and best practices to be shared across both groups

The Renault-Nissan Alliance and Daimler AG today announced a broad strategic cooperation that will enable both groups to already realize benefits quickly from a range of concrete projects as well as sharing of best practices. The two groups also announced an equity exchange that will give the Renault-Nissan Alliance a 3.1% stake in Daimler, and Daimler a 3.1% stake in Renault and a 3.1% stake in Nissan.

According to Dr. Dieter Zetsche, Chairman of the Board of Management of Daimler AG and head of Mercedes-Benz Cars, “Daimler and the Renault-Nissan Alliance are combining common interests to form a promising foundation for a successful, strategically sound cooperation that is based on a number of very concrete and attractive project cooperations. Our skills complement each other very well. Right away, we are strengthening our competitiveness in the small and compact car segment and are reducing our CO2 footprint – both on a long-term basis. We know that we can make brand-typical products based on shared architectures. The individual brand identities will remain unaffected.”

Carlos Ghosn, Chairman and CEO of the Renault-Nissan Alliance, said: “The Renault-Nissan Alliance knows how to work successfully in collaborative partnerships, and this experience is extremely valuable in today’s and even more tomorrow’s global auto industry. This agreement will extend our strategic collaboration and create lasting value for the Renault-Nissan Alliance and Daimler as we work on broadening and strengthening our product offering, efficiently utilizing all available resources and developing the innovative technologies required in the coming decade.”

Highlights of the Cooperation

Following intensive and productive talks, specific projects have been agreed upon and will be implemented with immediate effect. Specifically:

New common architecture for small vehicles

The successor to the current smart fortwo, a new smart four-seater and the next-generation Renault Twingo will be engineered on the basis of a jointly developed architecture. All vehicles will clearly differ from each other in terms of product design. One main characteristic of the new architecture will be the unique rear wheel drive concept used by current smart vehicles.

The launches of the jointly developed models are planned for 2013 onwards. The smart plant in Hambach, France will be the production location for the two-seater versions, while the Renault plant in Novo Mesto, Slovenia will be the production location for the four-seater versions. Right from its market launch, the jointly developed future models will also be available with an electric drive.

Powertrains

The focus of the cooperation in the powertrain area is on the sharing of highly fuel-efficient, diesel and gasoline engines between the Renault-Nissan Alliance and Daimler.

The Renault-Nissan Alliance will provide 3 and 4 cylinder gasoline and diesel engines out of its portfolio to Daimler, which will then be adapted and modified to reflect Mercedes’ characteristics. The result is a win-win situation for both sides: Daimler will be able to utilize Renault-Nissan Alliance engines and capture additional sales potential for Mercedes-Benz’ future lineup of premium compact cars, while the Renault-Nissan Alliance will improve its capacity utilization.

Daimler will provide gasoline and diesel engines out of its current portfolio to Infiniti. This includes 4 and 6 cylinder gasoline and diesel engines. The result is a win-win situation for both sides: Infiniti will be able to utilize Daimler engines, while Daimler will improve its capacity utilization.

Daimler, Renault and Nissan will also cooperate on future gasoline and diesel engines. Final production decisions for newly, co-developed engines will be taken at a later time, seeking a production network that is well balanced, thus benefiting all sides.

The area of engine cooperation will be driven by a technical concept that ensures the preservation and clear distinctiveness of the individual respective brand and product identities, while at the same time providing a highly competitive cost structure. First, a high level of standardization of the non-brand-relevant components will provide substantial savings for both partners. Second, the use of separate, brand-specific technology packages will ensure that the requirements of the respective brands are met.

A key objective is to increase competitiveness of all partners through a substantial increase in volumes, leading to economies of scale and cost sharing in development.

Collaboration on light commercial vehicles

The companies have also agreed on a close cooperation in the light commercial vehicle segment. Mercedes-Benz Vans will expand its portfolio to offer an all-new entry-level, intended for commercial usage, from 2012 onwards. The technical basis of this van will come from Renault and will be produced at the Renault plant in Maubeuge, France. Both partners will benefit from higher unit sales, better capacity utilization, shared investment burden, resulting in a better overall cost basis.

In addition to cooperating on small commercial vehicles, selected powertrain components will also be shared to enlarge mid-size van product offering and sales volumes. This includes a small diesel engine and transmissions which Daimler will procure from Renault-Nissan for its mid-size van, the Mercedes-Benz Vito. This additional entry-level motorization will generate additional unit sales for Mercedes-Benz and optimized capacity utilization at Renault.

Equity Exchanges

This strategic cooperation is underscored through a one-time cross-shareholding structure which enables the three companies to exchange, benchmark and create synergies on the basis of a long-term mutually beneficial relationship. The overall construction of the deal is based on the principle of a 3.1/3.1/3.1 percentage cross-holding between Renault, Nissan and Daimler; it will be transacted through an exchange of shares:

* Daimler will get 3.1% of Renault’s newly issued shares;
* Daimler will get from Renault 3.1% of Nissan existing shares;
* Renault will get 3.1% of Daimler shares
* Renault has independently agreed to exchange 1.55% of Daimler with Nissan for 2% of Nissan shares;
* Renault and Nissan will each hold 1.55 % of Daimler treasury shares.

Mercedes-AMG Provides Additional Details on Progress of SLS AMG E-CELL Electric Super Sports Car

This is a very cool car with a battery pack nearly the size of Tesla's Roadster. Unfortunately, the price tag will likely be just as cost prohibitive to "average" car buyer.

Source: Green Car Congress:

The Mercedes-AMG SLS AMG E-CELL. Click to enlarge.

Mercedes-AMG, the performance brand within Mercedes-Benz Cars, provided an update on its development of an electric version of the SLS AMG, the development of which it announced last July.

With a power output of 392 kW (526 hp) and 880 N·m (649 lb-ft) of torque, the gullwing with electric drive is part of the company strategy entitled “AMG Performance 2015” which aims to continually reduce fuel consumption and emissions. The SLS AMG E-CELL may see a limited production run, the company says.

Traction is provided by four synchronous electric motors each achieving a maximum 12,000/rpm and positioned near to the wheels. Compared with wheel-hub motors the unsprung masses are substantially reduced. One transmission per axle transmits the power.

Powertrain components of the E-CELL. Click to enlarge.

The electric 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-liter V8 engine developing 420 kW (571 hp), which can accelerate to 100 km/h in 3.8 seconds. However, unlike the combustion engine, torque build-up with an electric motor is instantaneous—maximum torque is available virtually from a standstill.

The SLS AMG E-CELL drive incorporates a liquid-cooled high-voltage lithium-ion battery featuring a modular design with an energy content of 48 kWh and a capacity of 40 Ah. The maximum electric load potential of the battery, which consists of 324 lithium-ion polymer cells, is 480 kW.

The intelligent parallel circuit of the individual battery modules helps to maximize the safety, reliability and service life of the battery. The 400-volt battery is also charged by means of targeted recuperation during braking while the car is being driven.

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.

Another perspective on Mercedes-Benz SLS AMG E-CELL powertrain components. Click to enlarge.

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.

Battery pack modules are located in front of the firewall, in the center tunnel and behind the seats. Advantages of this solution include the vehicle’s low centre of gravity and balanced weight distribution. The installation of the drive components required no changes to the model’s weight-optimized aluminium spaceframe.

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.

This front-axle design, already tried and tested in motorsport, enables the agility and driving dynamics of the electrically-powered SLS AMG to attain the same high levels as the V8 variant. Another feature is the speed-sensitive power steering with rack-and-pinion steering gear: the power assistance is implemented electrohydraulically rather than just hydraulically.

The technology vehicle is slowed with the aid of AMG ceramic composite brakes, available as an optional extra for the series production model, which feature 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% 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 tire grip. The lower rotating masses at the front axle also ensure a more direct steering response—particularly noticeable when taking highway bends at high speed. The ABS and ESP systems have been adapted to match the special application spectrum of the permanent all-wheel drive.

The air outlet openings on the hood and the vehicle sides have been modified for enhanced aerodynamics. The front apron has not only been brought further forward, but also helps to guarantee an optimized 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 centimeters at speeds above 120 km/h (75 mph) 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 AMG instrument cluster and center console 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 center 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.