At IAA Mobility 2021 in Munich, Porsche is presenting the Mission R concept electric car that combines advanced technologies and sustainable materials, such as natural fibre-reinforced plastics, with a passion for racing. In addition to a progressive design, the extremely low-slung, all-electric competition car features the characteristic lines of the sports cars from Stuttgart-Zuffenhausen.
The Mission R is on a par with the performance level of the Porsche 911 GT3 Cup. The power output remains constant over the duration of the race, so there is no thermally induced de-rating—a major advantage of the electric motors with direct oil cooling developed by Porsche. The electric motor on the front axle produces up to 320 kW (435 PS) in race mode.
In qualifying mode, the all-wheel-drive car has a peak system output of more than 800 kW (1,088 PS). The continuous system power in race mode is 500 kW (680 PS). Top speed is more than 300 km/h (186 mph). The lightweight electric racing car, which tips the scales at around 1,500 kg, accelerates from zero to 100 km/h in less than 2.5 seconds.
The power output from the two electric motors is transmitted to the front and rear wheels via straight-toothed input gearboxes and mechanical limited-slip differentials. The modular design of the drive system also helps to improve cost efficiency in customer motorsports: the gearbox, electric motors and pulse-controlled inverters (PCI) on the front and rear axles are identical.
The Mission R is pre-equipped for over-the-air technology. It is conceivable, therefore, that, in the event of problems occurring during the race, Porsche Motorsport experts from Weissach would be able to access data from the customer cars via a remote interface and then help with troubleshooting.
Highly efficient motors with direct oil cooling. In the Mission R, Porsche is offering a preview of the next generation of electric motors. In 2018, a team of Porsche engineers and technicians in Zuffenhausen and Weissach began to develop extremely powerful and highly efficient electric motors.
The most important innovation of these permanently excited synchronous machines (PESMs) is the direct oil cooling of the stator, which enables very high peak and continuous power output levels to be achieved, in addition to delivering a very high level of efficiency.
While in conventional electrical machines the cooling fluid flows through a jacket outside the stator, in the case of direct cooling, the oil flows directly along the copper windings. This allows more heat to be dissipated directly at source. In addition, the slots in the stator can be made smaller, which leads to greater efficiency in real driving cycles. An innovative stator seal is used to prevent the coolant from entering the rotor chamber.
An optimization algorithm was used to determine the optimum shape and position of the magnets in the rotor. The resulting geometry eliminates an old conflict of objectives: it combines excellent electromagnetic properties with high mechanical strength at very high speeds.
During production, the magnets are inserted into the rotor laminations and extrusion-coated with plastic. As a result, they do not move, despite high centrifugal forces, and the balancing quality of the rotor remains stable. At the same time, the plastic helps to dissipate the heat generated in the magnets.
As with the Taycan’s electric motors, the hairpin winding contributes to a high yield of power and torque while maintaining compact dimensions. The coils consist of rectangular wires that are bent and then inserted into the stator’s laminated core. Their shape is reminiscent of hairpins, hence the name. The open ends are welded together by laser.
High-end battery and 900-volt technology. The battery sits behind the driver in an e-core layout. Its total capacity is 82 kWh. This means it is designed for a sprint race format distance of 25 to 40 minutes. High-end cells are used to benefit from the high power density. Here again, direct oil cooling offers tremendous thermal advantages because it makes use of the entire surface of the cells, a large amount of heat can be transported from the battery into the cooling system.
Based on the 800-volt technology of the three-time Le Mans winner, the 919 Hybrid, the Porsche Taycan was the first car to enter production using this system voltage instead of the 400 volts normally used in electric cars. In the Mission R, Porsche is raising the bar a notch higher again with a voltage rating of more than 900 volts.
Using 900-volt technology will result in further improvements in continuous power, weight and charging time. At DC fast charging stations, the Mission R can be charged from five to 80% SoC (State of Charge) within approximately 15 minutes. The maximum charging capacity is 350 kW. The charge port is located beneath the middle of the spoiler.
The Mission R also features a further development of Porsche Active Aerodynamics (PAA) with Drag Reduction System (DRS) on the nose section and rear wing. It comprises three louvres in each of the two side air intakes on the nose section as well as an adjustable, two-section rear wing.
In addition to the innovative, battery-electric drive concept, the body of the concept car also focuses on CO2 reduction and sustainability: it is largely made of natural fiber reinforced plastic (NFRP), the basic material of which is made from flax fibers obtained from farming. This ecological material is also used for the front spoiler lip, the diffuser and the side skirts. NFRP is used extensively in the interior of the Mission R, such as the interior door panels, the rear bulkhead and the seat.
The interior design focuses on the driver in all areas. An ergonomically placed display between the controls on the steering wheel shows relevant data during the race. The monitor above the steering column shows the images from the side mirror cameras and the central rear-view mirror camera. A touch display to the right of the seat can be used to call up the driver’s biometric data, for instance. Numerous other cameras in the interior can be used to provide sequences for a live stream transmission.
With the Mission R project, Porsche is bringing real and virtual racing closer together. The monocoque driver’s module in exactly the same form also doubles as an e-sports simulator. The safety structure made of carbon fiber composite material combines high protection potential for the driver with low weight and a distinctive look. Porsche engineers and designers have named the newly developed carbon roof structure the “exoskeleton”. It combines safety cage and roof skin.
At 4,326 millimeters in length, the Porsche Mission R is slightly shorter than the current 718 Cayman series, but it is noticeably wider at 1,990 millimeters and with an external height of 1,190 millimeters is also significantly lower.
In the course of the last few years, with the Mission E (2015) and Mission E Cross Turismo (2018) concept studies, Porsche has given unmistakeable previews of its first all-electric sports car model series to come. The Porsche Taycan sports saloon (2019) and the Taycan Cross Turismo cross-utility vehicle (2021) closely resemble the two concept studies in terms of appearance and technology, and have already been successfully launched on the world markets. With the Mission R, Porsche is presenting its vision of what customer motorsports will look like in the future.