BMW i8 Concept – emotional, dynamic and efficient.
The BMW i8 Concept and the fascinating approach that underpins it embody the vision of a sustainable contemporary sports car brought to life. Its innovative plug-in hybrid concept combines the modified electric drive system from the BMW i3 Concept - fitted over its front axle - wîth a high-performance three-cylinder combustion engine producing 164 kW (220 hp)/300 Nm (221 lb-ft) at the rear. The electric motor in the BMW i8 Concept is a full-capability unit which can also power the car on its own, if required. However, working in tandem allows the two drive systems to display their respective talents to the full, delivering the performance of a sports car but the fuel consumption of a small car.
Acceleration of 0 to 100 km/h (62 mph) in under five seconds combined wîth fuel consumption in the European cycle of under three litres per 100 kilometres (approx. 94 mpg imp) and average customer fuel consumption of between five and seven litres per 100 kilometres (40.4 - 56.5 mpg imp) - even when driven hard - are figures currently beyond the capability of any vehicle powered by a combustion engine of comparable performance. Thanks to its large lithium-ion battery, which can be charged from a domestic power supply, the BMW i8 Concept can travel up to 35 kilometres (approx. 20 miles) on electric power alone. A large proportion of short everyday journeys can therefore be completed wîth zero emissions. The car's electric-only mode allows it to enter emissions-capped central areas of cities wîth access restrictions in place for petrol or diesel-powered vehicles. The i8 Concept's efficiency rating is further enhanced by its ability to generate energy at both axles. The electric motor at the front axle recoups maximum energy every time the driver brakes, while a high-voltage alternator hooked up to the combustion engine charges the battery, if required. Added to which, the 2+2-seater offers enough space for four people, giving it a high level of everyday practicality.
The emotional design of the BMW i8 Concept ensures its qualities are clear for all to see. Its dynamic proportions give the BMW i8 Concept the appearance of surging forward before it even turns a wheel and lend visual form to its extraordinary performance. The sophisticated concept behind the upward-swivelling doors fixed to the A-pillars underlines the car's sporting capability and opens up access to the front and rear seats at the same time.
A series of air inlets allow the air to flow through and around the vehicle to optimum effect, ensuring extremely low drag. They also add visual emphasis to these advanced aerodynamics. Airflow plays an extremely important role at the rear of the vehicle as well. Intakes behind the passenger cell and at the rear provide a cooling flow of air through the engine compartment, while outlets in the rear diffuser and the flow of air around the rear wheels ensure the car is extremely efficient in terms of lift and downforce at both axles.
The LifeDrive architecture of the BMW i8 Concept has been carefully adapted to enhance the vehicle's sports car character, and therefore to deliver unbeatable performance and excellent driving dynamics. The motor in the front axle module and combustion engine at the rear are connected by an 'energy tunnel', which houses the high-voltage battery. This gives the car a low centre of gravity - and the dynamic benefits that come wîth it. The positioning of the electric motor and engine over their respective axles and the space-saving and well-balanced packaging of all components result in an optimum 50/50 weight distribution.
| ||Vital Stats|
|Engine : |
Power: 349 hp
Torque: 406 ft-lbs
The weight of every component inside the BMW i8 Concept has been minimised down to the very last detail, allowing the extra weight of the electric drive system and battery to be cancelled out. The BMW i8 Concept therefore presents the ideal environment in which to sample this very special drive concept on the road. The passengers sit - in typical sports car style - in an extremely low and enclosed position inside the CFRP-constructed Life module (mounted above the Drive module).
The sporting character of the BMW i8 Concept continues into the interior. Boasting a driver-focused environment unmatched by any BMW Group vehicle before it, the BMW i8 Concept immerses the driver fully in the unique driving experience. The purpose-built driver's position is geared squarely towards the person at the wheel and gives optimum access to all information and controls. The three-dimensional displays are crystal clear and flash up the relevant information for the driving situation at hand. The interior as a whole is defined by the functionality of a classical BMW sports car and majors on lightness and ease of use. The BMW i8 Concept is the sports car for a new generation - pure, emotional and sustainable.BMW i thinks beyond the vehicle.
An additional range of mobility services – which can also be used independently of the cars – will be an integral component of BMW i alongside the vehicles themselves. This should allow the creation of a new, profitable area of business over the long term and attract new customers to the company's brands. A totally new development in this area will be vehicle-independent mobility services. These will allow BMW i to offer bespoke mobility solutions representing a perfect combination of premium vehicles and premium services. The focus is on solutions which will improve usage of existing parking spaces, as well as intelligent navigation systems wîth local information, intermodal route planning and premium car-sharing. In addition to service packages developed in-house, the BMW Group is pursuing cooperations wîth partner companies as well as strategic capital investments wîth providers of mobility services. BMW i Ventures was established wîth this purpose in mind. The company aims to expand the product portfolio of BMW i over the long term wîth stakes in highly innovative service providers, such as MyCityWay and ParkatmyHouse.Purpose-built design – the LifeDrive concept.
when it comes to installation space and cannot be integrated into that vehicle without adding weight and compromising interior and boot space. Conversion cars thus do not represent the best long-term response to the challenge of e-mobility. The BMW Group engineers took a different approach, focusing squarely on the eventual usage of the BMW i vehicles in developing the LifeDrive concept. This new vehicle architecture meets the full range of technical requirements of an electric drive system (including a large battery), while keeping weight low, maximising range, creating generous levels of space, enabling supreme driving characteristics, and ensuring impressive safety for the battery and passengers alike.
In contrast to vehicles wîth a self-supporting body, the LifeDrive concept essentially comprises two separate, independent functional units. The Drive module integrates the vehicle's suspension, battery, drive system, and structural and crash functions into a construction made chiefly from aluminium. Its partner, the Life module, consists primarily of a high-strength and extremely lightweight passenger cell made from carbon fibre-reinforced plastic (CFRP). The use of this high-tech material across large sections of the car ensures that the Life module is remarkably light and, in so doing, helps to achieve both impressive range and improved performance. Added to which, the car's handling is also much enhanced, and the functional connection between the Drive module and the torsionally rigid Life module lends it a very distinctive dynamic character. The use of CFRP on this scale is unprecedented. Indeed, wîth the creation of its LifeDrive architecture the BMW Group has taken lightweight design, vehicle architecture and crash safety into a whole new dimension. By avoiding the need for modifications to accommodate the electric drive components, the LifeDrive architecture ensures the car is no heavier than a conversion vehicle of similar size. Intelligent lightweight design and the innovative use of materials allows the LifeDrive architecture to cancel out all the extra weight added by giving the car an electric drive train rather than a comparable combustion engine.
Another special feature of the BMW i3 Concept and BMW i8 Concept are their wheels, which are noticeably larger and narrower than those of their class rivals. Slimmer tyres generate far less drag and rolling resistance, reduce unsprung masses and, in so doing, allow the cars to travel further on a single charge and use less energy.Lightweight and safe.
Equally impressive as the vehicle architecture's benefits in terms of weight and handling is its performance in crash tests. Here again, the combination of the aluminium in the Drive module and the Life module's CFRP passenger cell demonstrates just how well lightweight design and safety can go together. Like the cockpit of a Formula One car, the CFRP passenger cell provides an extremely strong survival area. Pole impacts, side-on collisions and rollover tests highlight the impressive safety-enhancing properties of this extraordinarily robust material. While metal constructions require the addition of large energy absorption zones, special deformation elements in the CFRP structure allow large amounts of energy to be absorbed in an amazingly small area. Despite the heavy and sometimes concentrated forces, the material barely sustains a dent. Together, the high-strength CFRP passenger cell and intelligent distribution of forces through the LifeDrive module lay the foundations for optimum protection for the car's occupants and battery alike.The LifeDrive architecture of the BMW i3 Concept.
Both the BMW i3 Concept and the BMW i8 Concept have been designed around the innovative LifeDrive architecture. However, the geometric implementation of the concept differs in the two models, having been adapted to suit their different usages. The BMW i3 Concept features a horizontal-split variant of the LifeDrive concept optimised to accommodate the car's electric drive system. Here, the Drive module provides the solid foundations for the Life cell, which is simply mounted on top. The driving element of the Drive module's functional design is the battery, which is made as large as possible to give the
car better range. Bearing in mind the size of the BMW i3 Concept's battery, the most space-efficient place to store it was in the car's underfloor section. There, it occupies the whole of the module's central section, giving the car optimum weight distribution and a low centre of gravity and therefore enhancing its dynamics. The battery is penned in by aluminium profiles, which protect it from external impacts. Crash-active structures in front and behind it provide the necessary energy absorption in the event of a front- or rear-end collision. The electric drive system is, as a whole, much more compact than a comparable combustion engine, cleverly accommodating the electric motor, gear assembly and drive electronics – in space-saving fashion – within a small area over the driven rear axle. The BMW i3 Concept therefore features the optimum LifeDrive architecture configuration for a purely electric vehicle.
The chassis of the BMW i3 Concept is also ideal for city driving. Its enviably small turning circle and direct §teering responses are a recipe for outstanding agility, notably at low speeds. Rear-wheel drive allows the front axle to remain free from drive forces and therefore to carry out its §teering function to optimum effect. These elements team up wîth the electric motor – whose impressive torque from a standstill provides exceptional traction – to produce extremely dynamic handling characteristics.
The spacious Life module of the BMW i3 Concept allows the vehicle's interior to boast a totally new design. The integration of all the drive components within the Drive module removes the need for a centre tunnel bisecting the interior, through which power would previously have been transferred to the rear wheels. The BMW i3 Concept therefore offers significantly more interior space than other vehicles wîth the same wheelbase and – through solutions such as a full-width seat bench – also allows the interior to be adapted extremely effectively to the needs of urban mobility. Added to which, a pair of opposing doors and the omission of B-pillars provide a large entry area for passengers – and a generous view into the cutting-edge interior for admiring eyes. The BMW i3 Concept offers comfortable accommodation for four passengers and, wîth around 200 litres of boot space, room for their luggage as well. Úp front, underneath what would normally be the bonnet, the Life module gives the BMW i3 Concept a separate luggage area wîth space for the charging cable and other items passengers would rather not carry in the passenger compartment.The LifeDrive architecture of the BMW i8 Concept.
The BMW i8 Concept sees the LifeDrive architecture concept adapted to suit the vehicle's sports car character – i.e. primed to deliver leading performance and sharp dynamics. This interpretation of the LifeDrive concept takes its cues from the innovative hybrid concept of the BMW i8 Concept, which links up an electric drive system at the front axle wîth a combustion engine over the rear wheels to lay on an unparalleled driving experience.
In a departure from the purely horizontal configuration favoured for the BMW i3 Concept, the LifeDrive architecture of its BMW i8 Concept sibling also features vertical layering in the front axle module, passenger cell and rear axle module. The drive systems powering the BMW i8 Concept are integrated into the front and rear axle modules, wîth the CFRP Life module providing the bridge between the two. As a plug-in hybrid, the BMW i8 Concept is not designed purely for all-electric propulsion, and therefore carries fewer battery cells than the BMW i3 Concept. These are stored in the Life module inside an energy tunnel, a structure similar to a central transmission tunnel. The front and rear axle modules therefore combine wîth the passenger cell and battery to form a functional unit, which adopts not only load-bearing responsibilities but also extensive crash functions. The location of the high-voltage battery in the energy tunnel gives the vehicle a low centre of gravity, and this enhances its dynamics. Together wîth the positioning of the motor and engine over the axles, the result is optimum 50/50 weight distribution. Intelligent lightweight design and the innovative use of materials produce extremely low unsprung and rotating masses, which is good news for the car's driving dynamics, acceleration, range and fuel economy. All in all, the BMW i8 Concept offers the ideal environment in which to experience the special drive concept and distinctive sports car character of the BMW i8 Concept on the road.
The BMW i8 Concept's axles are designed to deliver optimum handling properties, in keeping wîth the car's sporting profile. The multi-link front axle provides the ideal geometric platform for an extremely flat and aerodynamically efficient silhouette. The front axle construction is also designed explicitly to handle the twin demands of the §teering and drive system. It eliminates any drive forces which may otherwise affect the §teering, ensuring optimum handling in every situation.
In the CFRP Life module passengers sit low down and enclosed – in classical sports car style – between the motor and engine. Between them runs the energy tunnel that intersects the interior. Swivelling doors fixed to the A-pillars provide large openings that allow access to both front and rear seats. Four seats make the BMW i8 Concept a practical everyday vehicle that brings together the full array of positive BMW attributes.Intelligent lightweight design.
Systematic lightweight design is a particularly important element of electrically-powered vehicles. An electric drive system (incl. battery) tips the scales at up to 200 kg heavier than a comparable combustion engine and full tank of fuel. (concept carz) And high vehicle weight is a major factor – alongside battery capacity –in restricting how far an electric car can travel on a single charge. As well as increasing such a vehicle's range, lower vehicle weight is also a ticket to noticeably improved performance. After all, a lightweight vehicle accelerates faster, is more agile through corners and brakes to a standstill more quickly. Lightweight design therefore paves the way for greater driving pleasure, agility and safety. In addition, lower accelerated mass means that energy-absorbing crash structures can be scaled back – and that, in turn, saves weight. The aim of the development engineers was therefore to achieve the electrification/hybridisation of the vehicles without adding weight. Alongside the innovative LifeDrive architecture, other aspects central to the BMW Group's success in cancelling out the extra weight of the electric components were systematic lightweight design and the innovative use of materials.
'The LifeDrive concept avoids the additional weight involved in making the necessary modifications to conversion concepts. At the same time, in both vehicles we've been able to cancel out all of the extra kilos added by the electric motor(s) through the innovative use of materials and intelligent lightweight design.' (Bernhard Dressler, Responsible for bodywork and equipment at project i)
The various components within a vehicle's structure have to deal wîth an extremely wide range of demands, which can only be addressed to full effect by a variety of construction methods. For each component, the BMW Group engineers therefore select the material to fit its usage profile and the demands placed on it, so that battery weight is no longer an issue. In order to meet the engineers' ambitious aims, every component has been rigorously developed, examined and, if necessary, modified to optimise its functional effectiveness and minimise weight. Designing the components specifically for their particular purpose ensures the vehicles work as well and weigh as little as possible. CFRP plays a major role in reducing weight. The extensive use of this material – e.g. in the Life module of the BMW i3 Concept and BMW i8 Concept – is unprecedented in volume vehicle production. CFRP is at least as strong as steel, but roughly 50 per cent lighter. By comparison, aluminium would save 'only' 30 per cent in weight over steel. All of which makes CFRP the lightest material available for vehicle body construction which does not compromise safety.
As well as 'conventional' CFRP components made from resinated carbon fibre weave, in some areas the BMW i8 Concept also contains specially woven CFRP structures known as 'braided profiles'. Here, CFRP preforms are woven like a sock over a mould. This allows much greater design freedom, and fewer joints are required. Flush-fitting connections also make the profiles extremely strong. The braided profiles are therefore used in areas – such as the door sills, doors and A-pillars – in which greater strength is required, not least in the event of a collision. The special manufacturing process involved makes it extremely easy to optimise wall thickness (by adjusting the diameter of the mould). Much more complex forms can also be achieved without bonding or the use of connecting pieces and, most importantly, produce far fewer waste cuttings. Lower material usage also reduces the energy requirement.Source - BMW