|The i3. Click to enlarge.|
At the Manhattan stop on its year-long “Born Electric” World Tour, BMW i featured the BMW i8 Concept Roadster—shown for the first time in North America—and the BMW i3 Concept. The i3 and i8 will become the first purpose-built electric and hybrid-electric production vehicles to be made primarily from carbon fiber when they come to market in 2013 and 2014 respectively. (Earlier post, earlier post.)
Also at the event, Mitchell L. Moss, director of New York University’s Rudin Center for Transportation Policy and Management, revealed the results of a new NYU-BMW i study which finds that, in the coming years and decades, fundamental changes in the demographic makeup of cities will profoundly alter the way people travel. (Post.)
i3 Concept. The eDrive system for the battery-electric i3 features an electric motor that develops 125 kW/170 hp with peak torque of 250 N·m. The electric concept model accelerates from 0 to 60 km/h (37 mph) in less than four seconds, and to 100 km/h (62 mph) in less than eight seconds. The torque is available across a wide rpm range, resulting in smooth power delivery. A single-speed gearbox sends the power to the rear wheels and accelerates the BMW i3 Concept to a top speed of 150 km/h (93 mph).
Intelligent power electronics ensure that the electric power onboard the BMW i3 Concept is used economically and efficiently. If the driver eases up on the accelerator, the electric motor acts as a generator, converting the kinetic energy into electricity which is then fed back into the battery. This results in a braking effect which the driver can make use of as necessary. Alternatively, the driver can select coasting mode, in which the zero torque control keeps the electric motor disconnected from the drive axle. In this mode the BMW i3 Concept coasts with virtually no power consumption, driven solely by its own kinetic energy.
ECO PRO mode allows drivers to increase the driving range of their vehicle and to reduce their power consumption. With ECO PRO+, the BMW i3 Concept takes this a stage further and operates exclusively in range-maximizing mode. In this mode the main electrical consumers such as the air-conditioning and heating systems operate at minimum power level, and auxiliary consumers such as the heated seats and heated mirrors are shut down altogether.
Another feature of the electric drive system is the high power-to-size ratio of the motor, BMW noted. Since this compact drive unit is mounted over the rear axle, together with the power electronics, transmission and differential, there is no reduction in interior space. The power needed to drive the motor and to operate all other vehicle functions is supplied by the lithium-ion pack, which is also positioned underfloor.
An intelligent heating/cooling system keeps the battery at its optimal operating temperature at all times The battery can be fully recharged in six hours at a standard power socket. If the BMW i Wallbox high-speed charger is used, an 80 per cent charge can be achieved in just one hour.
|i8 Concept Roadster. Click to enlarge.|
i8 Concept Roadster. The plug-in hybrid concept is the second variant of the 2+2-seater BMW i8 Concept. Compared with the Coupe variant of the BMW i8 Concept, the BMW i8 Concept Roadster has a slightly shorter wheelbase and overall length. Like the Coupe, the BMW i8 Concept Roadster is also built around the LifeDrive architecture, a fusion of independent functional units. For example, the carbon-fiber-reinforced plastic (CFRP) Life module gives the car an extremely lightweight passenger cell, while the Drive modules—made primarily from aluminum components—bring together all the car’s operational driving functions, such as the powertrain, chassis and safety structure.
The 96 kW (131 hp) electric motor on the front axle works in tandem with a turbocharged three-cylinder gasoline engine sending 164 kW (223 hp) through the rear wheels. Both units are in-house BMW Group developments and generate an aggregate system output of 260 kW (354 hp) and peak torque of 550 N·m (406 lb-ft). That is enough to accelerate the BMW i8 Concept Roadster from 0 to 100 km/h (62 mph) in five seconds on the way to an electronically governed top speed of 250 km/h (155 mph). The two-seater burns three liters of gasoline per 100 kilometers (78.4 mpg US) in the European test cycle.
The electric motor sources its energy from a lithium-ion battery which can be fully charged from a domestic power socket in less than two hours. The high-output battery is located in the energy tunnel between the front and rear axle modules in order to keep the car’s center of gravity as low as possible and therefore to maximize the car’s dynamic performance. The space-saving and well-balanced packaging of this and other drive and chassis components gives the sporting two-seater ideal 50:50 weight distribution.
With its battery fully charged, the BMW i8 Concept Roadster can cover up to 30 kilometers (19 miles) on electric power alone. If required, a high-voltage alternator hooked up to the combustion engine generates extra power, which is then stored in the hybrid battery. This range-extending function during the course of a journey allows the two-seater to travel further between charging stations.
The BMW i8 Concept Roadster can send power through the front, rear or all four wheels at the same time. Intelligent control electronics ensure that the optimum drive configuration is available for the situation at hand. The driver can view the driving mode currently engaged and monitor the activity of the two drive sources on the large information display in the cockpit.
Furthermore, the electronic systems ensure maximum energy recuperation under braking or when coasting. All of which means that the driver can enjoy maximum dynamic performance, unbeatable directional stability and minimal consumption and emissions at all times.
Embark investment. BMW i also announced that through BMW i Ventures, the company is investing in Embark, an award winning mobile app company dedicated to helping travelers navigate mass transit systems in several major cities, adding to its stable of mobility services providers which already includes MyCityWay and ParkAtMyHouse, as well as Chargepoint, the largest network of independently owned charging stations, which operates in more than 14 countries.
The company will also expand its DriveNow car sharing program, which recently launched in San Francisco and features a fleet of 70 all-electric BMW ActiveEs, to include San Francisco International Airport (SFO).
The BMW i Born Electric Tour kicked-off in Rome in June 2012, making stops in Dusseldorf and Tokyo prior to New York. Following the New York stop, the tour will travel to London (January 2013) and Paris (March 2013) before ending in Shanghai (June 2013). The seven-city, year-long global tour exploring the future of mobility is an initiative of BMW i.