Mercedes-Benz is showing the way ahead in environmentally responsible electromobility by presenting its near-series Concept BlueZERO at the North American International Auto Show in Detroit. Based on a single vehicle architecture, this intelligent, modular concept allows three models with different drive configurations, all of which are able to meet customer requirements in terms of sustainable mobility.

• The BlueZERO E-CELL with battery-electric drive and a range of up to 200 kilometres using electric drive alone.
• The BlueZERO F-CELL (fuel cell) with a range of well over 400 kilometres using electric drive
• The BlueZERO E-CELL PLUS with electric drive and additional internal combustion engine as power generator (range extender). This version has an overall range of up to 600 kilometres and can cover a distance of up to 100 kilometres using electric drive alone.

The three BlueZERO variants are based on the unique sandwich-floor architecture which Mercedes-Benz introduced some ten years ago, initially for the A-Class and then for the B-Class, one of the aims being to integrate alternative drive systems. Advantages of the modified construction include the positive effect of the major drive components on the centre of gravity, their space-saving design and the fact that they are extremely well protected within the vehicle underbody. The five-seater BlueZERO concept cars also set standards in terms of lightweight design, interior layout and body form.

“The flexible BlueZERO concept allows electromobility for every requirement and highlights the fact that Mercedes-Benz is the world’s only car manufacturer to already have in place all the key technologies for electric cars offering full everyday practicality”, says Dr Dieter Zetsche, Chairman of the Board of Management of Daimler AG and Head of Mercedes-Benz Cars.

The BlueZERO principle: flexible design, compact exterior, generously sized interior

All three BlueZERO variants share the same key technical components, while the design and vehicle dimensions are identical. Measuring just 4.22 metres in length, the BlueZERO models combine compact exterior dimensions with a generously proportioned and variable interior and luggage compartment. Five fully-fledged seats, a payload of around 450 kilograms and a luggage compartment capacity of over 500 litres make for outstanding everyday practicality. Thanks to their sandwich construction with a raised sitting position, the cars also offer an exceptionally high level of crash safety for the passengers and the technology, not to mention excellent all-round visibility.

Compared to electric cars based on conventional vehicle platforms and originally only designed for use in combination with internal combustion engines, Concept BlueZERO offers the following conclusive advantages:

Interior space is retained in full. As the energy accumulators/generators are integrated into the spacious sandwich floor, no compromises are necessary when it comes to passenger space, luggage capacity or variability.

The powertrain technology built into the sandwich floor ensures a low centre of gravity and, consequently, extremely reliable and agile handling.

Crash safety is of the extremely high standard associated with Mercedes thanks to the sandwich concept and the housing of major powertrain components between the axles.

As a result, the BlueZERO models are very different to conventionally constructed electric cars, which have the heavy and voluminous storage battery housed in the boot or in the rear-seat area, for example.

Modular design ensures flexibility and efficiency

“Our modular system allows different drive configurations for every customer requirement”, says Dr Thomas Weber, the member of the Daimler AG Board of Management responsible for corporate research and development at Mercedes-Benz Cars. “The modified sandwich-floor platform provides the perfect basis for a wide model range with electric drive systems. We are also developing a new, additional platform for future compact models with power units based on optimised internal combustion engines. The intelligent networking of both architectures enables us to develop our product portfolio extremely flexibly and efficiently. From 2009, we will be producing the first Mercedes fuel-cell cars on a small scale. Small-scale production of Mercedes-Benz cars with battery-electric drive alone will then commence in 2010. This means we are extremely well equipped for the future.”

All three BlueZERO models feature front-wheel drive, which is typical for this class of car. The Mercedes engineers have put together a modular system comprising several flexibly combinable drive components. These include state-of-the-art liquid-cooled lithium-ion batteries with a storage capacity of up to 35 kWh and the compact electric motor with a maximum output of 100 kW (continuous output 70 kW), which develops a peak torque of 320 Nm. All three variants accelerate from 0 to 100 km/h in less than 11 seconds. Their top speed is electronically limited to 150 km/h in the interests of optimal range and energy efficiency.

Electric drive systems with a range of 100, 200 and well over 400 kilometres

With a charging capacity of 15 kW, the powerful lithium-ion batteries in the BlueZERO E-CELL and the BlueZERO E-CELL PLUS can store enough energy for a range of 50 kilometres within 30 minutes. In terms of purely electrical drive, one or two hours of charging time is needed for a range of 100 and 200 kilometres respectively. The charging times are doubled if the charging capacity is 7 kW, as would be the case in a normal household. Both of these BlueZERO vehicles incorporate an electronic control unit that supports intelligent charging stations and billing systems.

At the rear, the BlueZERO E-CELL PLUS has the same 1.0-litre turbocharged petrol engine as the smart fortwo as an additional range extender. This compact three-cylinder powerplant has an output of 50 kW at a constant 3500 rpm. If required, it can recharge the 17.5-kWh lithium-ion battery by means of a similarly rated alternator. A range of up to 600 kilometres is possible on a single tank. The purely electrical, locally emission-free range is up to 100 kilometres. The BlueZERO F-CELL with fuel-cell drive achieves a range of well over 400 kilometres with zero emissions (as per NEDC).
BlueZERO design: both elegant and functional

Leading-edge technology is uniformly and attractively packaged in all three BlueZERO variants. The unique and distinctive Mercedes design idiom displayed by the body highlights the progressive nature of Concept BlueZERO straight away.

The powerfully elegant front end is dominated by the radiator grille with its centrally located star. The excellent aerodynamics of the BlueZERO are partly due to the closed front apron, whose design means that cooling air intakes are not required. The 20-inch wheels have also been aerodynamically optimised, while low-friction tyres reduce rolling resistance.

The striking character lines along the flanks lend the BlueZERO an extremely dynamic side line and accentuate its bionic structure inspired by nature. This characteristic feature of the Mercedes-Benz bionic car was adapted and modified for the BlueZERO models. These elements lend the body its dramatic power.

New-quality light production

The compact rear end of the Concept BlueZERO is characterised by tail lights in the shape of a curved “L”. In addition, the Mercedes designers have achieved a new-quality light production: transparent lenses produce a red light curtain which tapers smoothly towards the sides, creating a lightly diffused effect. This effect is repeated, albeit in white this time, by the front headlamps. What’s more, the front lights feature new lens technology and a plexiglass edge to produce “C” shaped daytime driving lights with the help of state-of-the-art LED technology.

Intelligent technology made visible

Translucent surfaces make the normally concealed technology visible. The light-grey tailgate is made completely from lightweight but highly robust Lexan that allows a view of the aluminium structure that makes up the rigidifying frame, for example. At the same time this transparent tailgate provides a view of the vehicle interior, making the advantages of the sandwich-floor platform obvious at a glance: for maximum customer benefit, the luggage compartment and passenger area remain fully usable, since there are no technical components that need to be accommodated here.

“It was very important for us to ensure that the guiding Mercedes-Benz principle of ‘Fascination and Responsibility’ was clearly reflected in the design of the Concept BlueZERO”, says Mercedes-Benz design chief Gorden Wagener. “This is yet another clear statement that environmental awareness and driving pleasure will continue to go together in our vehicles in the future. We want people to realise at first sight that the Concept BlueZERO is definitively not a lesser option.”

The Mercedes-Benz designers have emphasised this aspiration by introducing paint finishes in three new ALU-BEAM colours. Each of the three variants makes its individual mark: the BlueZERO E-CELL is painted in a fresh ALU-BEAM Yellow, while the BlueZERO F-CELL has ALU-BEAM Green paintwork. Confidence-oozing ALU-BEAM Orange was chosen for the BlueZERO E-CELL PLUS.