|The Concept B-Class E-CELL PLUS. Click to enlarge.|
Mercedes-Benz is presenting its first electric vehicle with Range Extender at the 2011 Frankfurt International Motor Show: the Concept B-Class E-CELL PLUS. Equipped with a Li-ion battery pack from Deutsche Accumotive (a joint venture of Daimler and Evonik), the E-CELL PLUS has a battery-only range of up to 100 km (62 miles). A 50 kW (67 hp), 1.0-liter three-cylinder turbocharged gasoline engine range extender delivers a total range of up to 600 km (373 miles).
The electric drive generates a peak power output of 100 kW and a continuous output of 70 kW. At low speeds, the engine charges the battery via a generator. At higher speeds—e.g., on prolonged highway stretches—it additionally serves as a driving engine, acting on the front wheels together with the electric motor via a newly developed automatic transmission. In combined driving mode the vehicle emits 32 grams of CO2 per kilometer.
|Concept B-Class E-CELL PLUS. Click to enlarge.|
The two drive units are compact and are housed in the engine compartment at the front together with the transmission and the generator. The lithium-ion battery pack and the fuel tank are located in a false floor at the rear—the “Energy Space”—which has been developed specially for alternative drives. For other drive variants it is also possible to install gas or hydrogen tanks here, for example.
Activation and deactivation of the combustion engine take place fully automatically; the drive unit selects the most fuel-efficient mode in every driving situation. With the Concept B-Class E-CELL PLUS there are basically two operating modes, depending on the battery charge status:
When the battery possesses sufficient energy, the vehicle runs locally emission-free on electric power alone. The battery can be charged using any standard domestic power outlet or at a public charging station, by means of the charge socket integrated in the rear bumper and the 3.3 kW on-board charger. Rapid charging is also possible with this vehicle, enabling a charging time on the order of one hour.
When the battery charge status drops below a certain limit, the combustion engine is activated (Range Extender mode).
Acceleration from 0 to 100 km/h in approximately 11 seconds and the top speed of 150 km/h (93 mph) are both attainable in either operating mode. In order to ensure the most efficient possible motoring, two variants are possible, depending on the vehicle's speed:
Below a speed of around 60 km/h, the combustion engine and generator attend to on-board power generation (series mode). In this case, the combustion engine is run in the most fuel-efficient mode.
At speeds of over 60 km/h the combustion engine acts as a driving engine together with the electric motor (parallel mode), transmitting the generated power to the front axle. Any excess power generated by the combustion engine is used to charge the battery and to run the ancillary units.
When the car goes into production, remote checking and remote configuration of the vehicle will be possible by means of the Vehicle Homepage. The driver will be able to access his or her vehicle via the internet, using PC or smartphone. In this way, it will be possible to check the current charge status of the lithium-ion battery or to verify the vehicle's current range on a map.
A smart charging feature will allow the customer to select a desired time for the beginning of a journey. The system then ensures that the battery is fully charged and, if desired, that the vehicle is air-conditioned at this point in time. The Vehicle Homepage offers further convenience functions, such as a route planner designed specifically for electric vehicles.