The Mercedes-Benz S500 plug-in hybrid will go on sale in the UK for £87,965.
Mercedes says the plug-in S500 can travel around 20 miles on electric power alone, as well as returning a combined 100.9mpg and CO2 emissions of 65g/km. The 0-62mph sprint is completed in 5.2 seconds, and the saloon has a claimed top speed of 155mph.
At the heart of the plush four-door is Mercedes-Benz’s twin-turbocharged 3.0-litre V6 direct injection petrol engine. The 90-degree unit, already fitted to a range of recent models including the new CLS400, kicks out 328bhp and 351lb ft.
The petrol engine is supported by a disc shaped electric motor mounted within the forward section of the S500 Plug-In Hybrid’s standard seven-speed automatic gearbox. The brushless motor delivers 114bhp and 251lb ft of torque.
The electric motor draws its power from an 8.7kW/h lithium-ion battery mounted within the floor of the boot, which is reduced by 135 litres in capacity from a standard 530 litres to 395 litres. The recharge time from a standard public charging point is put at two hours.
Altogether the petrol engine and electric motor provide Mercedes-Benz’s latest hybrid model with a combined system output of 436bhp and 479lb ft of torque.
By comparison, the S500 saloon’s twin-turbocharged 4.7-litre V8 direct injection petrol engine produces 449bhp and 516lb ft of torque.
The existing S400 hybrid, which uses a mild hybrid set-up that combines a naturally aspirated 3.5-litre V6 direct injection petrol engine and an electric motor, boasts a combined system output of 302bhp and 273lb ft.
The electric motor, battery and associated power electronics of the S500 plug-in hybrid add 200kg to the kerb weight of the new car, taking it to 2140kg.
The hybrid system operates in four different modes: hybrid, e-mode, e-save and charge, allowing the driver to choose between petrol-electric or pure electric running when there is sufficient battery charge.
A further innovation is a so-called haptic accelerator pedal, which vibrates to prompt the driver to slow down for added efficiency.
In e-mode, the new Mercedes-Benz is claimed to possess a zero-emissions range of 20.5 miles. This will be extended in selected countries, including China, through the use of a larger capacity battery to meet various regulations, according to Joachim Schommers, head of engine development.