BMW ActiveE Concept Points the Way to an Electric Future

BMW’s rather long electric vehicle history dates back to the late 1980s. Typically, this automaker has used its regular models for its EVs. The first was a battery powered 3 Series sedan, and now it’s 600 MINI E variants – electrically powered MINI Coopers converted to electric power – that are in service in California, New York, New Jersey, and several European locations.
The BMW Concept ActiveE, using the BMW 1 Series Coupe, joins the MINI E as part of the Project i Megacity Vehicle Initiative for minimizing environmental impact while preserving BMW’s ‘Ultimate Driving Machine’ experience. BMW plans an even larger fleet of electric 1 Series cars to gain more experience with EVs, with serial production of these electric cars beginning in the first half of the next decade. These could be marketed under a BMW sub-brand.

Like all BMWs, the Concept ActiveE is a rear drive car. It features a 170 horsepower electric motor located in the rear axle that’s been developed specifically for this model, featuring maximum torque of 184 lb-ft that’s available from a standstill. Unlike asynchronous electric motors, it provides relatively high torque even at higher speeds, which makes it more like a combustion engine. The car accelerates from 0-60 mph in about 8.5 seconds to an electronically limited top speed of 90 mph.
Battery modules replace the driveshaft, fuel tank, and engine. Besides a low center of gravity, the car also features the familiar BMW characteristic of near 50-50 weight distribution. Interior space provides four full-size seating positions with the same amount of head, leg, and shoulder room as conventional BMW 1 Series coupes. Trunk capacity exceeds that of the BMW 1 Series Convertible with the top down. Batteries bring a weight penalty, though, with vehicle weight climbing to about 3900 lbs.

An advanced lithium-ion battery pack developed especially for the Concept ActiveE by BMW and SB LiMotive, a joint venture between Samsung and Bosch, provides a real-world driving range of 100 miles. Charging can be handled by different power sources with any required conversion handled by the battery control system. Charging time is about three hours on European 230/240 volts drawing 50 amperes and 4 ½ hours from the North American grid at 32 amperes.
The Concept ActiveE features rear wheel Brake Energy Regeneration that increases range by up to 20 percent. When the accelerator pedal is released, the electric motor acts like a generator to convert kinetic energy into electricity that’s stored in the battery pack. Because of the drag created by regenerative braking, in urban traffic about 75 percent of all deceleration is accomplished without using the brake pedal. For greater deceleration, stepping on the brake pedal activates the conventional hydraulic braking system. In addition, Dynamic Stability Control applies selective braking and motor management during emergency braking. Electric power steering is retained from the production BMW 1 Series.

A driver can remotely activate the car’s electric heating and air conditioning system via a smartphone and BMW ConnectedDrive before a trip and while connected to a charging station. The advantage? This allows interior pre-heating and pre-cooling using plug-in grid power rather than the battery, which brings the cabin to a comfortable temperature before starting a drive. This lessens the need for battery-powered heating or cooling while driving, which leaves more battery power for the electric motor. Pre-heating and cooling can also be timer controlled. Using a mobile phone, a driver can also determine charge status and range of travel along with public charging station locations and how much charging time is required for a sufficient charge to return home.
Inside, a battery charge status display replaces the tachometer. A second display shows the current being drawn from the battery and also what’s being fed back through regenerative braking. Yet another displays locations of electric charging stations.
The Concept ActiveE won’t be mistaken for a standard 1 Series on the street. Besides its unique graphics, the car’s completely closed rear apron shows it is entirely emissions-free without the need for an exhaust system…a stand-out feature for any vehicle.

Source:-http://www.greencar.com/articles/bmw-activee-concept-points-way-electric-future.php