Mercedes-Benz reckons it won’t be just one technology that paves the way to sustainable mobility. After showing the 200 km range all-electric BlueZERO E‑CELL at the NAIAS in January, the German giant is to create a family of modularly-constructed, liquid-cooled Lithium-ion electric cars by adding two more derivatives of the close-to-production vehicle in Frankfurt next week. The BlueZERO E-CELL PLUS extends the range to 600 km using a turbocharged petrol engine as a range extender generator, while the BlueZERO F-CELL is fuel-cell-powered with a range of about 400 km.
The BlueZERO E-CELL PLUS is part of a family of modularly constructed electric cars, which will enable Mercedes-Benz to meet all customer requirements for sustainable mobility in the future. In this variant of the concept vehicle, the electric motor of the purely battery-powered BlueZERO E-CELL is combined with an additional three-cylinder, turbocharged petrol engine. Putting out 50 kW, the compact combustion engine is installed in the area of the rear axle and can charge the battery while the car is being driven.
The CO2 bonus for the battery-electric driving mode reduces the vehicle’s emissions to only 32 grams of CO2 per kilometre. The range extender enables the BlueZERO E-CELL PLUS to drive for up to 600 km, of which up to 100 km can be driven in electric mode with zero local emissions. The long combined range makes the BlueZERO E-CELL PLUS fully suitable for everyday use and assures that the customer will reach his or her destination even with a depleted battery. After all, the car can be refuelled quickly and easily at any normal filling station.
Battery with superior lithium-ion technology
During rapid charging with a charging capacity of 20 kW, the high-performance, 18 kWh lithium-ion battery of the BlueZERO E-CELL PLUS can store enough power within around 30 minutes for a 50 kilometre cruising range. The complete electric range of 100 kilometres requires a charging time of somewhat more than an hour. Charging time with a standard charge cycle at a conventional household outlet with 3,3 kW is approximately 6 hours. Special on-board electronics support the intelligent charging stations and billing systems used by electric fueling stations. Advantages of lithium-ion batteries compared to other battery technologies include their compact dimensions, high output and energy density, high charge efficiency and long service life.
Concept BlueZERO - the triad of electric mobility
Mercedes-Benz is showing the way to environmentally compatible electric mobility with the near-series Concept BlueZERO. The vehicle’s intelligent modular concept enables a single vehicle architecture to be used to create three models with different drive system configurations.
The third drive version is the fuel cell powered BlueZERO F-CELL, with a range of about 400 km on electric power and therefore also without any local emissions. All three BlueZERO models feature front-wheel drive, which is typical for this class of car. The drive components have been modularly organised by the Mercedes engineers and can be combined as needed. These include state-of-the-art liquid-cooled lithium-ion batteries with up to 35 kWh capacity, and a compact electric motor with a maximum output of 100 kW (sustained output: 70 kW). The maximum torque of 320 Nm is available from the electric motor’s first revolution, and it surpasses the value attained by today’s V6 petrol engines at 2,500 rpm. Like its two sister models, the BlueZERO E-CELL and the BlueZERO F-CELL, the BlueZERO E-CELL PLUS can accelerate from 0 to 100 km/h in less than eleven seconds. To ensure optimum range and energy efficiency, the top speed is electronically limited to 150 km/h.
"The Concept BlueZERO offers a triple demonstration of the technical maturity of alternative drive systems from Mercedes-Benz. Electric vehicles with battery electric or fuel cell drive systems will not truly be on an equal footing with today's combustion engine drive systems until the customers are confident that there is a sufficient infrastructure of electricity and hydrogen refueling stations,” says Prof. Herbert Kohler, Head of E-Drive and Future Mobility and also Chief Environmental Officer at Daimler.
Modular architecture for flexibility and efficiency
The three BlueZERO variants were developed on the basis of the unique sandwich-floor architecture known from the A-Class and B-Class. The advantage of the enhanced design is that the key drive components are installed in the vehicle’s underbody in such a way that they take up little space, ensure a good centre of gravity, and are maximally protected. The BlueZERO models therefore differ considerably from conventionally designed electric cars, which have heavy and voluminous storage batteries installed in the boot, for example, or in the area of the backseat. All three BlueZERO variants share key technological components and have identical designs and vehicle dimensions. Even though they have compact exterior dimensions, the 4.22-meter-long BlueZERO models have a spacious and versatile interior and cargo space. The vehicles’ five full-size seats, approximately 450 kilograms of payload, and more than 500 litres of cargo capacity make them suitable family cars.
“Our modular system permits different drive configurations for each customer requirement,” says Dr. Thomas Weber, the Daimler Board of Management Member responsible for Group Research and Mercedes-Benz Cars Development. “The improved sandwich floor platform serves as the perfect basis for a diverse range of vehicles with electric drives. We are currently developing an additional platform for future compact models that have drive systems using optimized internal combustion engines. The smart linking of both architectures will allow us to expand our product range in an extremely flexible and efficient manner. Beginning in 2009, we will manufacture the first small batch of Mercedes fuel cell cars. In 2010, they will be followed by a small batch of Mercedes-Benz vehicles that run solely on electric power supplied by a battery. Thanks to these measures, we are excellently positioned for the future.”
Fun to drive
Mercedes-Benz aims to continue to combine environmental awareness and driving fun. One way in which the Mercedes-Benz designers have emphasised this aspiration is by introducing paint finishes in three new ALU-BEAM colours. Each of the three variants makes its individual mark: Confident ALU-BEAM Copper was chosen for the BlueZERO E-CELL PLUS. The BlueZERO E-CELL is painted a fresh ALU-BEAM yellow; the BlueZERO F-CELL appears in ALU-BEAM green.
Mercedes-Benz feels it won’t be just one technology that paves the way to sustainable mobility in the future, however. Instead the company is responding with solutions that are every bit as varied as the demands. The individual technologies are being used in specific applications where they can provide the greatest advantage with respect to optimal consumption and emission values. Mercedes-Benz views the development of electric cars with battery and fuel cell drives for local zero-emission driving as a means of supplementing the extremely clean and economical BlueEFFICIENCY and hybrid vehicles already available today. However, the unrestricted and convenient operation of electric cars still faces a series of challenges, including high system costs, insufficient infrastructure and short cruising ranges.
Advanced diesel and petrol engines will remain the driving force for automobiles for a long time to come - not only for individual mobility in passenger cars (especially over long distances), but, more importantly, for freight transport in trucks. Despite all the progress that Mercedes-Benz has once again so emphatically documented with the Concept BlueZERO, electric cars will not be replacing vehicles with combustion engines any time soon. The electrification of modern, high-tech engines will, however, play an increasingly important role in the drive system mix of the future.