With the 2018 Pikes Peak International Hill Climb now less than two weeks away, Volkswagen outlined the drivetrain technology in the I.D. R Pikes Peak, its first fully-electric racing car. (Earlier post.)
The I.D. R Pikes Peak features two interlinked, integrated lithium-ion battery blocks on board, located to the right and left of the cockpit. They feed energy to two separate high-performance electric motors for the front and rear axles. Together, they provide performance of 500 kW (680 PS).
The actual performance level is controlled electronically, depending on the situation on the track. This means that the neutral driving behavior ideal for a racing car is achieved when accelerating out of a tight turn, for example, as the front wheels also have to transmit steering forces to the track in addition to the drive power. Accelerator or brake pedal movements are transmitted digitally with e-gas and brake-by-wire, a braking system with electronic signal transmission.
We are breaking new ground with the I.D. R Pikes Peak: This is the first time that Volkswagen will be competing in a race with a fully-electric car. Alongside the elaborate aerodynamic concept and the special requirements for the sports car chassis, the development of the electric drivetrain was the greatest challenge.—François-Xavier Demaison, Technical Director at Volkswagen Motorsport
The I.D. R Pikes Peak itself produces up to 20% of the electrical energy required for the 19.99-kilometer (12.42-mile) race via regenerative braking. This procedure also contributes part of the brake performance. A conventional brake system provides the additional deceleration required. The brake-by-wire system in the I.D. R Pikes Peak is the prerequisite for this.
The interplay between recovery and mechanical braking is controlled by electronic systems that the driver does not even notice.—Marc-Christian Bertram, Head of Electrics/Electronics at Volkswagen Motorsport
During development of the batteries for the I.D. R Pikes Peak, Volkswagen Motorsport engineers benefited from the know-how of the technical departments for e-mobility at the parent company in Wolfsburg and at the Preproduction Center (VSC) in Brunswick.
Technical development at Volkswagen has workshops and laboratories for performing stress tests on batteries. First of all, we ran tests with individual battery cells and modules. With a racing car, you have to be aware of special requirements for cabling and insulation. Volkswagen already has plenty of experience of high-voltage technology. It was a great help to be able to make use of that.—,François-Xavier Demaison
The engineers did more than just conform to the strict safety standards of the world motorsport governing body FIA for Formula E and the hybrid cars in the LMP1 category, which compete in the Le Mans 24-hour race. During development of our battery systems, Volkswagen used the strict testing procedure from production development, said Bertram.