Audi says the frameless doors and a coupé-type roof line allow the fusion of a large SUV and four-door luxury coupé

Audi says the frameless doors and a coupé-type roof line allow the 'fusion of a large SUV and four-door luxury coupé'

The new Audi Q8 is fitted with mild hybrid technology that integrates a lithium-ion battery and a belt alternator starter (BAS) into a 48-volt primary electrical system.

The rechargeable battery is located underneath the luggage compartment floor and stores 10 Ah of electrical capacity. Audi says the SUV can coast between 34 and 99mph with the engine switched off, then the BAS restarts the engine 'quickly and very comfortably'.

During deceleration, the BAS can recover up to 12 kW of energy. The start-stop range starts as low as 13mph. In customer operation, the technology package reduces fuel consumption by up to 0.7 liters per 100 km, Audi claims.

At launch, the Audi Q8 is fitted with a 3.0 TDI (Q8 50 TDI). It generates 286PS and delivers 600Nm (442.5 lb-ft) of torque to the crankshaft. It accelerates the SUV from 0 to 62mph in 6.3 seconds on its way to a top speed of 144mph.

Audi also says the crankcase and the cylinder heads have separate coolant circuits so the ideal temperature level can be set for any driving situation. Cast-in channels cool the pistons with oil. Their rings and the wrist pins are designed for minimum friction, while the oil pump is fully variable.

Switchable hydraulic bearings connect the engine to the subframe of the front axle. In idling, they eliminate vibrations with soft characteristic curves while during driving they suppress vibrations from the power unit with higher damping – 'allowing the TDI to always provide a highly refined ride'.

A smaller three-litre diesel with 231PS (Q8 45 TDI) and a 3.0 TFSI petrol-engine car with 340PS (Q8 55 TFSI) will follow early next year.

The flagship five-seat SUV is making its world debut in Shenzhen, China, at the second 'Audi Summit'. In S line specification it includes HD Matrix LED lights, 21-inch alloy wheels and adaptive air suspension.

A high-end Vorsprung edition due shortly after launch gains Valcona leather, dynamic all-wheel steering, 22-inch alloy wheels, head-up display and a full leather package as standard.

UK introduction is scheduled for summer 2018.

The Q8 is produced at VW Group's Bratislava plant, where VW's Touareg is also made (both on platform VAG MLB Eco (according to just-auto/QUBE's car model database). Although there is considerable aluminium content (and hot-formed steel) in the Q8, the 3.0 TDI weighs 2,145kg. Cast aluminium parts make up 15 per cent of the weight of the body-in-white, with components such as the suspension strut towers in the engine compartment and the connecting parts between sills and longitudinal members being constructed of the alloy. The side panels as well as large areas of the floor, the rear wheel housings and the roof consist of aluminium plates, as do the frameless doors,  front wings and the tailgate.