BMW says the series development process for a new plug-in hybrid version of the Mini has almost been completed. It features a combustion engine and an electric motor enabling purely electric propulsion for the first time in a series production Mini.

Head of Mini brand management Sebastian Mackensen and Head of Mini series management Peter Wolf have been explaining the thinking behind the new model.

“With this model we want to convince Mini customers of the benefits of hybrid drive”, says Mackensen, “and impress everyone who already has hybrid driving experience with Mini’s unique go-kart driving feel.” The company says the key to achieving this lies in intelligent energy management which is used to control how the combustion engine and electric motor operate together. For this reason, the first Mini plug-in hybrid model is not solely focused on efficiency, but also on the pursuit of driving fun.

The hybrid model is similar in appearance to the standard car. The charging socket for the high-voltage battery is integrated in the left side scuttle, and the cockpit has a familiar layout, although the start/stop button in the centre of the dashboard glows yellow instead of red. As usual,  the driver simply presses the button to start the car, which remains silent as the hybrid model always starts in electric mode. The rpm counter in the instrument cluster on the steering column has been replaced with a power display. When exactly the combustion engine starts varies depending upon on the vehicle’s speed and the intensity with which the driver operate the accelerator pedal.

“After a short time, the driver gets a feel for this”, promises Wolf. The hybrid Mini makes full use of the electric motor’s entire torque, which is available right from standstill, allowing for catapult-like acceleration. Even after leaving the slower pace of the city, this vehicle maintains its zero-tailpipe emissions at motorway speeds. The high-voltage battery under the rear seats provides power for long-lasting electric driving. AUTO eDRIVE standard mode permits speeds of up to 50 mph, whilst in MAX eDRIVE mode speeds of up to 78 mph are possible. For Mackensen this is a question of character: “In a hybrid MINI model, driving electrically must also be an exhilarating experience. This means that entirely electric driving is not limited to speeds of 30 or 40 km/h, but to speeds well beyond city traffic pace.”

“As far as the chassis and suspension are concerned, nothing changes from the conventionally driven model variants”, says Wolf, “and the set-up benefits a lot from the hybrid concept”. Thanks to the eDrive components, which are positioned very low down at the rear, the car’s centre of gravity is lowered and the weight is evenly balanced between the front and rear axle in order to help agility.

The Hybrid concept provides another benefit: the electric motor transmits its power to the rear wheels, the combustion engine to the front wheels. Since the intelligent energy management is linked to the Dynamic Stability Control (DSC), traction and drive stability can be optimised via the drive system. “As soon as there is any risk of drive slip, the second drive unit is activated to provide additional traction when starting off or ensuring a high level of steering precision when cornering”, explains Wolf.

Intelligent energy management offers a further opportunity for both power sources to work together effectively. In SAVE BATTERY mode, the combustion engine powers the car whilst at the same time, the high voltage battery can retain charge at a constant level or increase charge via a generator. Extended driving in SAVE BATTERY mode enables enough power generation for purely electric driving later.