Audi's Board Member for Technical Development has confirmed plans to offer an SQ7.
Speaking to Autocar, Prof. Dr. Ulrich Hackenberg said "The new Q7 will be available in the market next year but the electric turbo will come a bit later in the Audi SQ7 available in 2016.”
Hackenberg declined to go into specifics but the model could use the same powertrain as the RS5 TDI concept. As you may recall, it had a twin-turbo 3.0-liter V6 TDI engine with a "supplemental electric turbocharger" that was powered by a compact lithium-ion battery. This setup enabled the engine to produce 385 PS (283 kW) and 750 Nm (553 lb-ft) of torque. While those numbers don't seem to impressive by themselves, they allowed the concept to accelerate from 0-100 km/h in four seconds and consume less than 5.3 L/100km (44.3 mpg US / 53.2 mpg UK).