2008 L.A. Auto Show – BMW 7-Series ActiveHybrid
The Los Angeles Auto Show saw the world debut of the BMW Concept 7-Series ActiveHybrid. The concept shows the potential of BMW ActiveHybrid technology in the premium luxury car segment and is part of the BMW EfficientDynamics innovation strategy.
The objective of the 7-Series ActiveHybrid is to achieve much better fuel economy and lower emissions in a premium luxury car – a class not known for being particularly environmentally conscious.
Mild Hybrid Teamed With Potent V8
The BMW Concept 7-Series ActiveHybrid combines an 8-cylinder gas engine and electric drive as a mild hybrid. The drivetrain technology featured in the Concept Car allows enhanced driving dynamics together with a reduction in fuel consumption and emissions by 15% versus the same car running on an internal combustion engine only. BMW states that the ActiveHybrid does not compromise the driving dynamics, performance or features of the 7-Series.
BMW contends that there are no compromises to the original 7-Series equation when the mild hybrid is adopted. The ActiveHybrid Seven looks practically the same, has the same level of comfort and performance while getting better fuel economy with lower emissions through use of the mild hybrid technology.
Twin Turbo V8 Based on 750i Powerplant
The internal combustion engine portion of the BMW Concept 7-Series ActiveHybrid is a Twin Turbo V8 gasoline engine and high precision fuel Injection based on the 4.4L V8 of the BMW 750i. Maximum output of the conventional engine in the regular production model is 407 horsepower, with peak torque of 442 lb-ft.
BMW claims the V8 power unit is the most efficient engine in its class and is ideal for focusing on both driving dynamics and efficiency. BMW says its V8 is the only eight-cylinder gasoline engine in the world with its turbochargers mounted in the Vee between the two cylinder banks.
Electric Motor incorporated in Transmission Housing
The V8 is combined with an electric motor fully integrated in the transmission housing, developing maximum output of 20 hp and peak torque of 155 lb-ft. So with the mild hybrid concept, the electric motor boosts the dynamic driving potential of the eight-cylinder gasoline engine in a unique manner most appropriate for the character of the BMW 7 Series, giving the car better acceleration than the already great acceleration of the 750iL.
Regenerative Braking Supplements Power for Accessories
Using Brake Energy Regeneration, the electric motor supplies electric power to the power-consuming items on board the car, minimizing the direct conversion of fuel into electrical energy and maximizing the drive power available for enhanced driving dynamics.
BMW and Daimler AG Cooperated on the ActiveHybrid System
The hybrid components developed for the Concept Car are based on technology created by BMW and Daimler in their cooperation on hybrid drive systems. In this joint venture the two manufacturers have successfully developed components for hybrid drive including the power electronics and high-voltage batteries. Naturally, the hybrid drive system featured by BMW offers all the characteristics and highlights typical of the brand.
ActiveHybrid is based on a modular concept following a “Best of Hybrid“ strategy with the objective being selection of the best components for different vehicle segments. The components featured in the BMW Concept 7 Series ActiveHybrid – the mild hybrid transmission and V8 gas engine – supplement each other in the same manner as the full hybrid transmission and the V8 gas engine in the BMW Concept X6 ActiveHybrid.
The compact electric motor integrated in the transmission housing replaces the conventional alternator driven by the engine as well as the starter. Electrical energy is generated through Brake Energy Regeneration without impairing the power of the engine itself. Integrated power electronics, in turn, ensure compact design and safe and secure packaging of all hybrid components.
A high-performance lithium-ion battery integrated in the luggage compartment in accordance with the package of the car saves the energy generated and supplies power to the on-board network. Through its high storage capacity, the battery makes full use of Brake Energy Regeneration.
Thanks to the higher degree of electric power provided in this way, additional functions in the car are run completely under the electric power supply. The Auto Start Stop function preventing the internal combustion engine from running in the idle mode is a good example.
Slight Styling “Adjustments” Differentiate ActiveHybrid from Typical 7-Series
Other than wrapping the concept car with graphics, there are only slight styling differences between the ActiveHybrid Seven and the 750iL. One difference is an aluminum band stretching across the width of the front end beneath the license plate. This band is designed to be visually appealing and to provide controlled air flow for optimum aerodynamics.
The rear of the 7-Series ActiveHybrid Concept has an additional air guidance element made of aluminum and exhaust tailpipes with new contours identify the ActiveHybrid drive concept. As at the front end of the car, BMW has fitted an aluminium band integrated across the entire width of the vehicle in the rear fascia. This aluminum band forms the upper surround for the exhaust outlets.