The i8 Roadster and Coupe carry over the BMW i design language into another vehicle concept, and is awash with individual highlights that radiate elegance and fire the emotions.
The i8 Roadster’s soft-top roof has a visual lightness to go with its low physical weight and serves as a defining element of the silhouette in reinforcing the road-hugging impression made by the car’s low center of gravity. The i8 Roadster’s broad roof retracts fully into the rear end. A unique mechanism allows the soft-top to be folded into a compact package and stowed away in a perpendicular position, creating around 100 liters of additional storage space behind the seats.
The all-electric roof opens and closes very quietly in 15 seconds, a process which can be initiated while travelling at up to 50 km/h (31 mph). Dropping down the roof raises the rear window by around 30 mm into a comfort position.
BMW eDrive technology
Underpinning a new level of electric driving experience is an updated version of the lithium-ion battery developed for the BMW i8. The high-voltage unit is located centrally in the car’s underbody. Its cell capacity is up from 20 to 34 Ah and gross energy capacity rises from 7.1 to 11.6 kWh (net: 9.4 kWh). All of which means the electric motor has more energy at its disposal. The cell configuration allows a 9 kW/12 hp increase in peak output to 105 kW/143 hp, lacing quick sprints on pure-electric power with an even more vivid streak of dynamism.
In the standard driving mode, the new i8 Coupe and new i8 Roadster can be driven exclusively on the electric motor alone, from step-off to a speed of 105 km/h (65 mph), which is up from 70 km/h (43 mph) in the original i8. The combustion engine is only brought into play at higher speeds or when the driver stamps down hard on the accelerator, and is switched off again far more frequently when a measured driving style is maintained. Pressing the eDrive button allows both models to travel at up to 120 km/h (75 mph) on electric power alone. The electric range of the new i8 Coupe in the NEDC test cycle has increased to 55 km and the i8 Roadster posts a figure of 53 km.
The internal combustion engine has also undergone further optimization to ready it for the i8 Coupe and Roadster. The threecylinder unit extracts maximum output of 170 kW/231 hp from its displacement of just 1.5 liters, along with peak torque of 320 Nm (236 lb-ft). The system output produced by the electric motor and engine acting in unison is now 275 kW/374 hp. The i8 Coupe accelerates from 0 to 100 km/h (62 mph) in 4.4 seconds, while the i8 Roadster takes a tick longer with a time of 4.6 seconds. Both models have an electronically limited top speed of 250 km/h (156 mph).
Hybrid-specific all-wheel drive, precision-tuned chassis
The electric motor’s power is transmitted to the front wheels and the engine’s drive to the rear wheels, resulting in a hybrid-specific all-wheel-drive system that is controlled by the car’s intelligent energy management. In hybrid mode, the electric motor provides a power boost to assist the engine when the driver is accelerating with particular vigor.
When the navigation system’s route guidance function is activated, the intelligent energy management ensures the electric motor is employed as extensively as possible and as judiciously as possible from an efficiency point of view. The system analyses the route in full and sets up the powertrain management to run on purely electric power, particularly over low-speed sections of the journey
The model-specific tuning of the suspension and damping systems, the specially configured steering characteristics, a firmer roll stabilization set-up and targeted modification of the DSC parameters together guarantee all of the plug-in hybrid sports car’s trademark handling and performance qualities. Dynamic Damper Control is included as standard on both models. The standard 20-inch light-alloy wheels fitted to the i8 Roadster feature a lightweight construction and each weigh around one kilogram less than the lightest wheels previously offered for the i8.
The BMW i8 Coupe and Roadster come with Carpo interior trim as standard, comprising full-leather upholstery in Ivory White for the Coupe and Ivory White/Black for the Roadster. As well as Halo interior trim, the list of optional extras also includes new Accaro interior trim with an Amido/E-Copper colour scheme. Standard specification also includes features such as a leather sports steering wheel with multifunction buttons and shift paddles, electrically adjustable and heated seats, the multifunctional instrument display, the Driving Assistant including Surround View, the BMW Display Key and the Navigation system Professional. The main menu in the Control Display is now presented in the form of horizontally arranged tiles with a live mode.
Options available include a model-specific BMW Head-Up Display, the non-dazzling Laserlight with Selective Beam and acoustic pedestrian warning.