In a further sign that full-electric drive vehicles are headed for the mainstream, BMW Group will showcase a lithium-ion battery powered version of the MINI at next month's Los Angeles Auto Show ahead of a pilot project that will see 500 of the cars evaluated on US roads in 2009. Based on the current MINI Hatch, the MINI E will initially appear in two-seater form with rear seats dropped to make way for the battery pack. Rather than an in-hub motor arrangement, an electric motor mounted under the bonnet drives the front wheels through a single-stage helical gearbox derived from the Cooper S, and being all-electric, the full power kicks-in from a standing start delivering quite adequate acceleration of 0-62 mph in 8.5 seconds with a top speed electronically-limited to 95 mph.
To conserve energy and help achieve greater range (which is specified at an impressive 150 miles), the MINI E uses a regenerative braking system directly linked to the accelerator. Release the pedal and the electric motor acts as a generator, feeding the kinetic energy back into the system. Getting used to such a system takes a little time as we learned during our road-test of similar technology found in the Vectrix electric scooter, but once you've become accustomed to staying off the brakes it's remarkably easy to utilize it in the majority of driving situations. In the case of the MINI E, BMW estimate that if you can use it in city traffic for around 75 per cent of all deceleration the car's range can be extended by up to 20 percent.
If you do need to hit the anchors, the car's brake system also comes with a newly developed electric pump and the Electrical Power Assisted Steering (EPS) is the same as the one used in mass-produced MINIs.
The lithium-ion storage unit itself is made up of 5,088 cells grouped into 48 modules and packaged into three battery elements. It has a maximum capacity of 35 kilowatt hours (kWh) and transmits energy to the electric motor as direct current at a nominal 380 volts.
Recharging is via a standard power outlet but a high amperage wallbox will be supplied as standard that will speed up the full recharging time to just two-and-a-half hours. The wallbox is designed to be installed in the customer’s garage, though only lockable garages or similar buildings will qualify. A full recharge draws a maximum of 28 kilowatt hours of electricity from the grid which translates to one kilowatt hour per 5.4 miles and information on how much charge is left in the system is relayed to the driver via a battery level indicator behind the wheel.
Design-wise, the MINI E still looks like a MINI. All of the car's made for the pilot project will share the same dark silver paintwork on the panels and a silver roof incorporating a large yellow power plug logo. The same logo is also emblazoned on the the front and back of the car, the charger port lid (a handy reminder in-case you try to put petrol in), the door-jam and the dashboard trim.
The 500 MINI E's slated for the US trial will be produced at the company’s Oxford and Munich sites before being shipped to California, New York and New Jersey for testing by private and corporate customers on a one-year lease. The cars will then be returned to BMW for comparative tests. Because special tools and qualifications are required for servicing the vehicles, MINI will also set up a dedicated service base for customers in each of the states.
So the options appear to be steadily mounting for those looking into the ZEV market, lets just hope that renewable energy infrastructure can keep pace so that we can enjoy truly zero-emissions motoring - with no emissions at the tailpipe or the power plant - sometime in the not too distant future.
MINI E specifications
- Number of doors/seats: 3/2
- Length/width/height: 146.2/66.3/55.4 inches (3,714/1,683/1,407mm) - unloaded
- Wheelbase: 2,467mm (97.1 inches)
- Track front/rear: 1,453/1,461mm (57.2/57.5 inches)
- Turning circle: 10.7m (35.1 feet)
- Kerb weight: 1,465kg (3,230lbs)
- Payload: 195kg (430lbs)
- Gross vehicle weight rating: 1,660kg (3,656lbs)
- Cargo space (DIN): 60 liters
- Engine: Electric motor
- Output: 150/204 kW/hp
- Torque (from idle): 220Nm
- Max. rpm (cut off): 12,500 min-1
- Battery capacity: 35kWh, approx. 28kWh of which useable
- Battery weight: 260kg (573lbs)
- Battery charge time: 23.6 hours at 110 V/12 A(1.3 kW) / 4.4 hours at 240 V/32 A (7.0 kW) / 2.9 hours at 240 V/48 A(10.6 kW)
- Battery cooling: Air cooling via temperature-, load- and speed-sensitive fans
- Peak current: Short bursts of up to 900A
- Front wheel suspension: Single-joint MacPherson spring strut axle with anti-dive control
- Rear wheel suspension: Longitudinal link with centrally mounted control arms, z axis
- Front brakes: 294mm Vented disc
- Rear brakes: 259mm Disc
- Road stability systems: DSC adapted to modified kerb weight and wheel load (always on), low-friction recuperation control via DSC, ELUP (electronic under pressure pump) brake boost
- Steering: Rack and pinion with electronic power steering (EPS)
- Type of transmission: Single-stage helical gearbox
- Axle load distribution: 750/715 front/rear in kg
- Tyres: All-season Runflat 16"
- Performance Ratings
- Power-to-weight ratio (DIN): 9.76 kg/kW
- Acceleration 0–100 km/h (0-62 mph): 8.5s
- Top speed: 95.0mph
- Range (FTP 72): 150miles, 240km
- Consumption (FTP 72): 0.19 kWh/mls (0.12 kWh/km)
- CO2: nil
