The two vehicles will adopt the hybrid technology, which now features a 13.5-kilowatt-hour lithium-ion battery, from the S 560 e. The electrical power is 90 kilowatts, the additional torque is 440 newton-metres, and the electrical range is 50 kilometres in the New European Driving Cycle (NEDC). The torque output together with the OM 654 four-cylinder diesel engine is 700 newton-meters from an engine speed of 1,400 rpm; the top speed under electric power alone is 140 km/h.
Mercedes-Benz and Bosch jointly developed the electric motor specifically for the 9G‑Tronic plug-in hybrid transmission. The hybrid drive unit accommodates the torque converter, the separating clutch and the e‑machine. The separating clutch, torsional vibration damper and torque converter lock-up clutch are integrated into the e‑machine’s rotor.
Four driving modes from purely electric, "Hybrid" and "E-Safe" (battery is conserved) to "Charge" (combustion engine charges the battery) are available. The so-called Eco Assist aids the driver in coasting and recuperation by combining navigation data with traffic sign recognition and information from the intelligent safety assistants. Charging takes around seven hours at a socket outlet, but Mercedes-Benz also offers a new on-board charger featuring twice the charging power: 7.2 kilowatts from a wall box fully recharges the batteries within two hours.