Mercedes-Benz expands plug-in hybrid rollout with 2 models this year; new battery tech in S 500 e in 2017
Later this year, Mercedes-Benz will add the seventh and eighth plug-in hybrids to its line up. (Earlier post.) The new GLC Coupé 350 e 4MATIC and the E 350 e will join the S 500 e; C 350 e (Sedan, Wagon and long version for China); the GLE 500 e 4MATIC; and the GLC 350 e 4MATIC. The hybrid (plug-in and conventional) portfolio from Mercedes-Benz currently comprises 13 models.
The E 350 e will use the 9G-TRONIC plug-in-hybrid transmission and the latest generation of electric motors to deliver top rankings in fuel consumption, ride comfort and dynamism. The E 350 e is also the first hybrid from Mercedes-Benz with a high trailer towing capacity of up to 2,100 kg.
|Two technology world premieres are being presented in the E 350 e: along with a newly developed electric motor, the E 350 e is also the first vehicle to feature the newly developed 9G-TRONIC plug-in-hybrid transmission. Click to enlarge.|
The next major technology jump will be made in 2017, starting with the facelift of the S 500 e—a fully electric operating range exceeding 50 km (31 miles) will be made possible by a further development of the lithium-ion battery together with a further optimized, intelligent operating strategy. The new lithium-ion battery will deliver a rated capacity of up to 13.3 kWh.
Daimler AG began its own development and production of lithium-ion battery systems in 2009. The highly efficient battery system comes from the wholly-owned Daimler subsidiary Deutsche ACCUMOTIVE, which will for the first time also be supplying batteries for plug-in-hybrids from Mercedes-Benz.
The third-generation hybrid transmission used in the E 350 e evolved on the basis of the 9G-TRONIC PLUS automatic transmission. The torque converter, clutch and electric motor are housed in the hybrid drive unit. The remarkably compact design has been achieved by integrating and connecting the clutch, torsional vibration damper and torque converter lock-up clutch within the rotor of the electric motor. The newly developed torque converter with its powerful and highly efficient hydraulic circuit offers the customary outstanding smoothness when pulling away in hybrid mode.
Developed together with Bosch as part of the EM Motive joint venture, the electric motor was specially designed for the 9G-TRONIC plug-in-hybrid transmission. In combination with the likewise new and much more efficient power electronics, it was possible to further increase output and torque to 65 kW and 440 N·m respectively.
|New electric motor in the E 350 e is the product of the EM-motive Joint Venture and was specifically developed for the 9G-TRONIC plug-in-hybrid transmission. Click to enlarge.|
This is 5 kW more output and 100 N·m more torque compared to the preceding system in the C 350 e. This high level of torque is instantly available from stationary, and allows tremendous agility when pulling away, plus sporty driving characteristics.
Further improvements to the intelligent operating strategy also increase the efficiency of the hybrid. The new thermal management links the vehicle’s cooling system with the navigation data, and predictively balances out temperature peaks by advance cooling.
The recuperation function was also improved in the E 350 e; energy recovery not only sets in when approaching a slower-moving vehicle, but also before entering speed limits or on downhill gradients.
Depending on the driving profile, the sedan is able to cover 18-33 km (11-21 miles) all-electric, for fuel consumption of 2.1 liters of fuel per 100 kilometers (112 mpg US) (NEDC).
The innovative hybrid traction head with clutch electric motor and converter in combination with the intelligent operating strategy allows the system to achieve the optimum comfort and efficiency in all driving situations.
When the hybrid model is driving fully electrically, the clutch is disengaged while the internal combustion engine is decoupled and switched off.
The clutch likewise remains disengaged during energy recuperation, the electric motor then acting as a generator and using the flywheel mass to charge the battery.
The clutch is engaged during boost and sailing operation, or in Charge mode, and the intelligent hybrid control system actuates the electric motor according to current power requirements.
The clutch remains engaged when driving with the internal combustion engine alone, and the intelligent hybrid control system switches the electric motor to free-running mode.
All the plug-in-hybrids have the following operating modes:
Hybrid: All hybrid functions, such as electric mode, boost and recuperation are available and are deployed for optimum fuel efficiency.
E-mode: used for all-electric driving in inner-city areas or because the battery holds sufficient charge for the remainder of the journey.
E-save: the charge status of the battery is maintained to allow all-electric driving in an environmental zone at a later stage in the journey.
Charge: Serves to charge the battery via the combustion engine while on the move, to enable all-electric driving in an environmental zone at a later stage in the journey, for example.
Silent start: the vehicle starts virtually silently and runs in electric mode. At this point the combustion engine is generally kept switched off.
Boosting: The internal combustion engine is assisted with extra output by switching on the electric motor.
Energy recuperation: Energy is recovered during braking, and fed to the battery. This energy can then be used at a later stage for electric driving or the boost function.
Haptic accelerator pedal: Supports fuel-efficient driving. A resistance point indicates the maximum available electric output. A double impulse signals that the driver should remove their foot from the accelerator pedal in order to switch off the combustion engine and decouple it from the drive train.
Intelligent drive management: Intelligent operating strategy for hybrid vehicles, anticipates the course of the road and the traffic situation for maximum efficiency. This includes radar-based recuperation, an anticipatory shifting and operating strategy, a route-based operating strategy and ECO Assist.
Pre-entry climate control: The desired interior climate can be set before starting the journey—cooling in the summer, heating in the winter. This function can be activated via a pre-set departure time or via smartphone using the Mercedes me connect app.
Retrieval of vehicle status: It is additionally possible to control the charging process or check the charge status and the current electric range via the Mercedes me connect app.