BMW Concept ActiveE

BMW's next chapter in its EfficientDynamics program calls for a new all-electric vehicle to complement its current fleet of leased Mini E electric subcompacts. To accomplish its self-prescribed mission, it enlisted the help of the 1 Series coupe and a revised synchronous electric motor to create a new show car called the Concept ActiveE. It's the epitome of electromobility in the true BMW sense, the automaker claims, and with the Mini E, continues to pave the way towards the ultimate goal of a mass-produced 'Megacity Vehicle'.

The heart of the concept is, of course, its electric powertrain. Engineers designed the unit to replace the 1 Series' combustion engine, fuel tank, drivetrain, and rear axle. The actual motor is enclosed in the would-be differential casing, while the lithium-ion battery modules take the place of the propshaft and also fit snugly under the front hood. ActiveE keeps the 1 Series's rear-wheel drive layout, as well as its 50/50 weight distribution, and combined with the instantaneous high torque of the new motor, promises to live up to the brand's distinct driving spirit.

Making a grand total of 170 horsepower and 184 foot-pounds of torque, the motor was built to provide generous amounts of grunt at high road and engine speeds. That's in addition to the Concept ActiveE's immediacy of power, as in other EVs. The electric powertrain has been tuned to behave similar to that of a combustion engine, by reducing torque gradually under high load, rather than abruptly. BMW points out that the 3900-lb. car can hit 60 mph in around 8.5 seconds and achieve a top speed of 90 mph.

Samsung's SB LiMotive partnered with engineers in Munich to develop the innovative power supply. Their lithium ion battery cells are grouped into compact modules that utilize individual liquid cooling systems to boost the vehicle's 100-mile single-charge range. Thanks to the battery's intuitive management control unit, users have the flexibility to charge their vehicle at any number of outlets, regardless of voltage or amperage. The control unit calculates power conversions and allows the batteries to charge at a fast pace. Engineers have quoted 3 hours to fully charge the units while plugged into a 230/240 volt European-spec outlet. On a more North American-like 32 amp plug, it'll take 4.5 hours.

On the move, the Concept ActiveE replenishes lost energy through what BMW calls Energy Recooperation. Once off the accelerator, the ActiveE's kinetic energy is used to turn a generator and create storable electricity. At the same time, the Brake Energy Regeneration system activates, illuminating the brake lights and engaging the rear brakes. If used often, Energy Recooperation can boost the EV's range by 20%. Meanwhile, BMW claims that in 75% of deceleration, the driver does not need to use the brake pedal. Should a higher measure of stopping power be required - such as in a panic situation or when coming to a full stop, the driver presses the brake pedal and the regular hydraulic system is engaged, enacting the front brakes as well.