You have JavaScript DISABLED. This web site has been designed for browsers with javascript enabled and will not function correctly without it. For information on how to enable JavaScript CLICK HERE.
Following the introduction of the Mercedes-Benz S400 Hybrid, currently laying claim to be the most fuel-efficient luxury-segment saloon with a petrol engine, Mercedes-Benz has now come out with the first “3-litre car” in the premium class - the Vision S500 Plug-in Hybrid.
The technology vehicle, which displays the future of Mercedes-Benz’ modular set of hybrid systems, is said to have a driving range of up to 30 kms solely on electrical power. The efficient drive system combined with the CO2 bonus for the battery-electric driving mode enables the car to achieve a certified consumption of only 31.25 kms/litre of petrol.
The experimental car’s impressive values are made possible by the combination of a plug-in hybrid with the efficiency-boosting BlueEFFICIENCY measures. At the same time, the Vision S500 Plug-in Hybrid has all of the strengths that are typical of the S-Class, ie top-notch comfort, outstanding safety and assertive performance. The drive system in the concept car consists of three main components: a powerful V6 petrol engine with a next-generation direct injection system, a 44 kW/60 bhp hybrid module and a lithium-ion battery with more than 10 kWh of storage capacity that can be recharged at charging stations. The Vision S500 Plug-in Hybrid is claimed to be able to go form standstill to 100 km/h in 5.5 seconds.
“Although it will take some time before this model can go into series production, our engineers will be working full steam to carry out the necessary integration measures and ensure that all components can meet the tough everyday demands required of a luxury long-distance saloon,” says Dr. Thomas Weber, member of the Board of Management of Daimler AG with responsibility for Group Research and Mercedes-Benz Cars Development. “We’ve already got all the key technology we need for such a dream car, which is why I see it being included in the next generation of the S-Class. The important thing now is that our development work be accompanied by the establishment of a full-coverage infrastructure that will allow the potential of this innovative drive system to be fully exploited.”
Layout of components
Whereas the extremely compact lithium-ion battery in the S400 Hybrid (0.9 kWh) can be housed in the vehicle’s engine compartment, the significantly higher-performing lithium-ion unit in the Vision S500 Plug-in Hybrid (over 10 kWh) requires more installation space. The battery is located behind the rear seats in the boot. The lithium-ion battery’s location above the rear axle provides crucial benefits, since it ensures that the vehicle has a balanced weight distribution and that the petrol tank remains adequate for long-distance cruising. In addition, the protected position of the tank ensures it is as safe as possible during crashes.
In accordance with the modular concept, the powertrain design for the Vision S500 Plug-in Hybrid is basically the same as that for the S400 Hybrid. One system-specific attribute is the presence of an additional clutch integrated between the combustion engine and the electric motor. This device decouples the two components in the pure electric drive mode, thereby ensuring the highest level of efficiency in the latter. Moreover, because it is fully integrated into the vehicle’s converter housing, the clutch does not take up any additional space.
Another key difference between the S500 Plug-in Hybrid and conventional hybrids involves the plug-in battery, which can be charged at charging stations, thereby enabling the S500 Plug-in Hybrid to travel up to 30 kms on electric power. The rapid charge cycle takes less than 60 minutes with a charging capacity of 20 kW. A standard charge cycle at a conventional household socket with 3.3 kW takes about 4.5 hours to recharge a completely discharged battery.
The model is also equipped with a compact onboard charger: Housed behind the side boot wall, this unit controls the recharging process and is protected against short circuits, voltage reversal, and voltage surges. The charging system also protects the battery by monitoring voltage, the charging level and charging time. The total weight of the electrical components in the current experimental vehicle is 215 kgs, whereby the lithium-ion battery weighs approximately 130 kgs. That’s much less than a conventional NiMH (nickel metal hybrid) battery with the same capacity, as the weight of such batteries ranges from 180 - 200 kgs.
Like the system employed in the S400 Hybrid, the hybrid module in the Vision S500 Plug-in Hybrid also comes with the ECO start/stop function. This feature also enhances safety and driving pleasure because of its boost effect, which has the electric motor providing powerful support to the combustion engine during the high-consumption acceleration phase. This system has already proved its practical viability in a slightly different configuration in the Mercedes-Benz Sprinter.
The lithium-ion battery not only serves as an energy storage device for the electric motor in the S500 Plug-in Hybrid; it is also linked via a DC-DC converter to the 12V on-board network, which provides power to standard consumers such as the headlamps and various comfort devices. To ensure a consistently high level of electrical efficiency, the voltage transformers are water-cooled via an additional low-temperature circuit.
“The Vision 500 Plug-in Hybrid is a new milestone on our path toward zero-emission mobility,” said Dr. Dieter Zetsche, Chairman of Daimler AG and Head of Mercedes-Benz Cars. “It is a luxurious and safe S-Class that offers superior driving performance while at the same time consuming less fuel than current compacts. All of this shows that our top models will also be able to combine automotive fascination with responsibility for the environment.”
Related story: 'Road to the Future’ for Mercedes-Benz
FAQ on hybrid vehicles
Talk about hybrids and alternative fuel vehicles in the MTM Forum