The 8G-DCT Plug-in Hybrid Transmission for the Mercedes-Benz Compact Car Family

With the new 8G-DCT plug-in hybrid transmission, Mercedes-Benz has electrified the modular 8G-DCT transmission family with a powerful and efficient plug-in hybrid powerhead. The plug-in hybrid transmission is launched as part of the new generation of the Mercedes-Benz compact car platform. Therefore, additional requirements concerning fuel consumption, pure electric driving possibility, torque capacity, minimal space, modularity and shifting performance are considered. This allows to fulfill increasing customer requirements in hybrid powertrains. The main elements of the highly compact and modular plug-in hybrid powerhead are an integrated dual clutch, an additional low-loss disconnect clutch and a new powerful 75 kW electric motor. The powerhead is characterized by its high functionality and extremely high efficiency in combination with the high torque of the electric motor. It provides all hybrid functionalities, such as boost, energy recuperation and pure electric driving. Special emphasis was placed on optimized efficiency of the powerhead by reducing the drag torque of the disconnect clutch as well as by means of on-demand cooling and lubrication. The actuation and cooling of the hybrid powerhead required only minimal adaptations to the basic transmission. The hybrid powerhead also allows starting the combustion engine in a very smooth manner, almost imperceptible for the driver. Within the transmission family the 8G-DCT plug-in hybrid transmission is therefore available for future use in electrified front-wheel drive compact car series.