The Vorsprung durch Technik brand’s latest paragon of economy will offer performance befitting its 245bhp and 480Nm outputs and all-electric, completely local emissions-free running at speeds of up to 100kmph. The Audi flagship gets a 2.0-litre TFSI engine, which has been modified in some areas, generates an output of 211bhp and makes a 350 Nm torque peak available between 1,500 and 4,200 rpm. The combustion engine works together with a disc-shaped electric motor which generates 54bhp and 210 Nm.
The permanent magnet synchronous motor is mounted in the space usually occupied by the torque converter in front of the modified eight-speed tiptronic transmission. A multi-plate clutch that operates in an oil bath connects or disconnects the electric motor and the TFSI engine, and does so ultra-precisely and gently in all situations. The smooth and fast-shifting hybrid transmission guides the torque to the front wheels, and its wide gear spread contributes to the efficiency of the Audi A8 hybrid.
The Audi A8 hybrid can drive at up to 100kmph purely on electric power. This gives the driver the choice of three modes: The ‘EV’ setting gives priority to the electric drive, while the ‘D’ option efficiently controls both the engine and the electric motor. The ‘S’ mode and the tiptronic gate place the emphasis on optimal acceleration. The hybrid saloon has five operating states: with the TFSI engine alone, with electric drive only or in hybrid mode; recuperation and boosting are also possible. Two displays show the driver all operating modes in detail.
The lithium-ion battery, which weighs 36.7 kilograms, is located in a crash-proof area in the boot. It provides 1.3 kWh of nominal energy and up to 40 kW of power. Two different methods are used to air-cool the battery, depending on need: air is either blown from the passenger compartment by a fan or via a separate cooling circuit coupled to the automatic air conditioning system. The battery is thus kept within the temperature window required for it to perform to its full potential over a wide range. The electric motor and the compact power electronics which serve as a controller between the electric motor and the battery are water-cooled.
