Audi Debuts Concept Hybrid Q7 SUV; Working with VW and Porsche on Hybrid Powertrains

12 September 2005

The Q7 hybrid concept. Click to enlarge.

Audi introduced a concept hybrid version of its new SUV, the Q7, at the Frankfurt IAA, and also announced that it was collaborating with its parent Volkswagen and Porsche on hybrid powertrains, although no contracts, letters or memoranda have yet to be signed.

This is a large, performance hybrid. The SUV, which weighs 2,410 kilograms (5,313 pounds) accelerates to 100 km/h in 6.8 seconds. Fuel consumption is 12.0 liters/100km (19.6 mpg US)—13% better than the conventional Q7.

The Q7 hybrid concept combines a 4.2-liter FSI V8 engine developing 257 kW (350 hp) and 440 Nm of torque with a 32-kW electric motor that adds up to an additional 200 Nm of torque.

The Q7 offers the Audi quattro permanent four-wheel drive and a 6-speed tiptronic transmission.

The V8 engine, taken from the latest Audi V-engine range, uses the same FSI direct-injection petrol technology featured in the RS 4 engine—the first use in a commercial-series engine of a technology which has powered the Audi R8 Le Mans racing car.

The electric motor is integrated into the driveline between the V8 engine and the automatic transmission’s torque converter. It is linked up to the FSI engine via a separating clutch that allows the vehicle to be propelled by either one of the drive units alone or by both acting in unison.

The hybrid uses a NiMH battery pack housed beneath the luggage compartment floor at the rear of the vehicle. A voltage transducer that supplies power to the vehicle’s electrical system can also be found here.

There are three basic operating modes: all-engine; all electric; and electric boost. Regenerative braking and engine overruning recharge the battery. Once the battery’s capacity has dropped to minimum, the combustion engine cuts in to recharge it.

In all-electric mode, the battery and motor can propel the Q7 hybrid at up to 30 km/h (18.6 mph) for a range of up to 2 kilometers (1.2 miles).

If the vehicle is coasting without the accelerator pedal depressed, the combustion engine is switched off. The same fuel-saving measure is initiated whenever the vehicle is stationary for over three seconds.

In an interesting touch, the Audi development team integrated solar cells into the SUV’s large-format glass sunroof, allowing the ventilation and air conditioning systems to be operated when the vehicle is parked. The driver can activate the climate control system remotely a few minutes before starting the journey. Part of the battery capacity of the hybrid drive system is used in order to achieve this.