sentences:  The lightweight (710 kg/1565 lb) vehicle featured a 360 cc engine in parallel with a 34 kW air-cooled AC induction motor.The 9 kWh nickel-cadmium battery could be recharged in four hours from a 220v electrical wall outlet, or from 30% to 80% state of charge in about two hours at a steady speed of 120 km/h.In 1998, Audi premiered a second iteration of the Duo plug-in hybrid, based on the Audi A4, at the Frankfurt Motor Show.