Audi re-jigs A1 e-tron hybrid

AUDI is pressing ahead with research and development of fuel-saving technologies, part of which is a second iteration of its petrol-electric A1 e-tron hybrid as part of a German government-funded “showcase for electric mobility” program that will start early next year.

Rather than the previous prototype’s 15kW rear-mounted 254cc rotary range-extender engine, the A1 e-tron now has a three-cylinder 1.5-litre petrol engine and two electric motors to boost total power output by 73 per cent to 130kW.

Fuel consumption has been almost halved, to about 1.0 litre per 100 kilometres – 0.2L/100km lower than a Holden Volt – and top speed has been increased beyond 130km/h.

More than a second has also been sliced off the A1 e-tron’s 0-100km/h acceleration time, which is now claimed to be less than nine seconds.

Audi calls the new A1 e-tron a ‘dual-mode hybrid’ because its 17.4kWh battery pack provides a range of up to 90km at speeds of up to 55km/h, with the petrol engine kicking in to generate power or drive the wheels for longer journeys or higher speeds, started and assisted by a second electric motor that also doubles as a generator to charge the battery pack.

A single-speed transmission and claw clutch enable the engine and motor to be engaged or disengaged from the driveline depending on the operating mode.

The original A1 e-tron’s range-extender engine was not directly attached to the driven wheels and the car could hit 130km/h, but had a shorter 50km electric-only range from the smaller 12kWh battery.

At speeds of 130km/h or more the new A1 e-tron’s petrol engine provides most of the propulsion but the electric motor can be deployed at any time to improve fuel-efficiency or boost performance.

The motor used for electric-only running produces 85kW of power and 200Nm of torque, while the petrol engine produces 95kW and 200Nm of torque and its attached electric motor is rated at 50kW and 210Nm.

Providing the battery pack under the rear seats has enough charge, drivers can select an electric-only running mode for urban driving, with efficiency or performance petrol-electric running modes can also available.

Audi says the A1 e-tron’s driving feel is “similar to that of a battery electric vehicle” as the driver does cannot detect gear changes or the switch between electric or petrol-electric running.

A fleet of first-generation A1 e-trons have covered more than 50,000km as part of a trial in Munich that will conclude at the end of this month.

The first stage of the trial involved the participants being lent a standard 1.4-litre petrol A1 to provide a base comparison before being given an e-tron to use just as they would have the conventional car.

Once participants got used to maximising its driving range and travelling more efficiently the average distances travelled on electricity alone rose from 76 per cent to 91 per cent.

Initial participants charged their A1 e-trons at public charging stations and at their workplace, while the second round had a wall charger installed at their home for overnight charging.

Other Audi technologies announced this week include a next-generation ‘iHEV’ idle-stop system that also deactivates the engine while freewheeling.

The system works best when used with another new technology Audi calls ‘predictive efficiency assistant’ (PEA), which helps the driver save fuel by helping them plan for the road ahead and reduce reactive accelerating and braking inputs.

Audi has also committed to offering at least one electrified variant under the e-tron banner in each vehicle segment by 2020.