The BMW i brand is synonymous with visionary mobility concepts and a new definition of premium quality that is strongly focused on sustainability. Following the world debut of the first production model, the BMW i3, the BMW Group’s next step will be to extend this revolutionary answer to the future challenges facing personal mobility to the sports car segment. At a driving event at the BMW Group’s Miramas test track in France, the BMW i brand is now presenting a prototype of its second production vehicle, the BMW i8. This plug-in hybrid model is the most progressive sports car of our time, extending the basic BMW i philosophy of sustainability to a new vehicle segment...
The BMW i8’s plug-in hybrid system is specific to this model. Developed and produced by the BMW Group, it marks the next step in the evolution of the Efficient Dynamics program. A compact three-cylinder petrol engine with BMW TwinPower Turbo technology is combined with an electric drive system and a lithium-ion battery which can be recharged at a standard household power socket. The 170 kW/231 hp petrol engine sends its power to the rear wheels, while the 96 kW/131 hp electric motor powers the front wheels. This configuration offers all-electric driving capability with a range of up to 35 kilometers (approx. 22 miles) and a top speed of 120 km/h (approx. 75 mph). With both drive systems engaged, it also offers road-hugging all- wheel-drive performance with powerful acceleration and dynamic torque vectoring during sporty cornering. The more powerful of the two powerplants drives the rear wheels. The hybrid system supplements this with power from the electric motor to deliver typical BMW driving pleasure combined with groundbreaking efficiency. Calculated using the EU test cycle for plug-in hybrid vehicles, the average fuel consumption of the BMW i8 at model launch will be less than 2.5 liters/100 km (over 113 mpg) with CO2 emissions of less than 59 grams per kilometer.
Optimal balance between performance and fuel economy: BMW i8 as an exciting evolution of the Efficient Dynamics strategy.
It is now more than a decade since the BMW Group launched its Efficient Dynamics vehicle development strategy, whose aim is to significantly improve both the performance and the efficiency of new BMW Group models. Efficient Dynamics combines evolutionary advances in existing technologies with the development of new and revolutionary drive concepts. Efficient Dynamics solutions include efficient lightweight design and aerodynamic concepts, high-performance drive systems based on TwinPower Turbo technology and BMW eDrive, and intelligent management of all energy flows within the vehicle. The new, revolutionary technology now being introduced on models of the BMW i brand will subsequently find its way into the vehicles of the BMW Group’s core brands.
BMW i is also setting benchmarks in the quest for zero CO2 emissions in urban driving. The research and development work carried out since 2007 as part of project i has laid the foundations for revolutionary mobility solutions strongly influenced by environmental, economic and social change around the world. The BMW Group is pursuing an integrated approach, as embodied in the new BMW i brand, which aims to achieve the necessary balance between individual needs and the global mobility requirements of the future. The BMW i focus is squarely on all-electric and plug-in hybrid mobility. Groundbreaking design, intelligent lightweight engineering, typical BMW driving pleasure coupled with zero emissions, intelligent energy management and resource- and energy-saving production processes are all combined into an innovative premium-quality package.
LifeDrive architecture with an aluminum chassis for the powertrain and a CFRP passenger cell: for more excitement, lower weight and optimized drag.
The LifeDrive architecture specially developed for BMW i vehicles offers the ideal platform for turning the tide of spiraling weight while at the same time achieving distinctive styling exclusive to BMW i. With a length of 4,689 mm, a width of 1,942 mm and a height of 1,293 mm, the BMW i8 has the proportions of a typical sports car. Its dynamic personality is also stressed by a long bonnet, conspicuous aerodynamic features, an elongated roofline, short overhangs and a long wheelbase of 2,800 mm. Characteristic BMW i form language wraps up this groundbreaking combination of sporty performance and efficiency in a charismatic 2+2-seater design.
The BMW i8 combines a drag coefficient (Cd value) of 0.26 with outstanding aerodynamic balance. The finely honed air flow around all parts of the vehicle body makes for an excellent lift/drag ratio, resulting in superb driving dynamics and stability.
Intelligent lightweight design – from the overall concept down to the smallest detail.
With its combination of the aluminum Drive module and the CFRP passenger cell (Life module), the BMW i8 is also an excellent example of intelligent lightweight design – one of the guiding principles of the Efficient Dynamics strategy. Use of the lightweight high-tech material CFRP, which also offers excellent crash performance, brings weight savings of 50 per cent over steel and around 30 per cent over aluminum, with equivalent or improved strength. These savings offset the weight penalty of the electric motor and the high- voltage battery, giving the BMW i8 an unladen weight of less than 1,490 kilograms. The LifeDrive architecture also brings benefits in terms of weight distribution. The battery pack is situated low down in the middle of the vehicle, resulting in a low and central centre of gravity, which improves safety. No other current model of a BMW Group brand has such a low centre of gravity.
The front-rear axle load distribution maximizes agility with a near-perfect 50:50 axle load ratio. The compact electric motor, together with the transmission and power electronics, are situated in close proximity to the electrically powered front axle. The highly turbocharged petrol engine, which is located together with its transmission in the rear of the BMW i8, likewise sends its power to the road via the shortest possible route, i.e. through the rear wheels. As a finishing touch to this excellent weight distribution, the lithium-ion battery pack is centrally located in the vehicle, slightly forward of the mid-point. In terms of crash safety, this is an ideal location for the battery, which is integrated in an aluminum housing.
The doors comprise a CFRP inner structure and an aluminum outer skin. This reduces the weight of the door by 50 per cent compared with a conventional design. The high-quality, naturally tanned leather of the seats highlights the “next premium”, sustainable philosophy of BMW i.
The magnesium instrument panel support saves weight on two fronts – firstly through intelligent design, leading to around 30 per cent weight savings compared, for example, with the BMW 6 Series. In addition, the high structural rigidity provides a strengthening effect which allows the number of components to be reduced, thereby lowering weight by a further 10 per cent. Innovative foam plastic technology used in the air conditioning ducts brings 60 per cent weight savings over conventional components, while also improving acoustics thanks to its sound-absorbing properties.
The fact that the power electronics and electric motor are directly connected reduces the amount of wiring required, while partial use of aluminum wiring brings further weight reductions. Lightweight design is also a feature of the BMW i8’s chassis systems – including the wheels, where the standard-fitted 20-inch forged aluminum wheels combine aerodynamic d