Almost a year after the first concept idea, Audi has started testing the new Audi RS Q e-tron. Audi tackles one of the biggest challenges in international motorsport. In January 2022, the RS Q e-tron will compete in the Dakar Rally.
Audi aims to be the first carmaker to use an electric powertrain in combination with a range extender to compete for the overall victory over conventionally driven competitors in the world's toughest rally. "Quattro was a game-changer in the World Rally Championship. Audi was the first to win the 24-hour Le Mans with an electrified driveline. Now we want to start a new era in the Dakar Rally and test and continue to develop our e-tron technology under extreme conditions, "says Julius Seebach, Head of Audi Sport GmbH and responsible for motorsport within Audi. "Our RS Q e-tron was created in record time from a blank piece of paper and stands for Vorsprung durch Technik."
The character of the Dakar Rally presents the engineers with unique challenges. The marathon rally lasts for two weeks, and the day stages are up to 80 km long. "It is a very long distance," says Andreas Roos, responsible for the Dakar project within Audi Sport. "What we are trying to do has never been done before. That is the ultimate challenge for an electric driveline."
As there are no charging ports in the desert, Audi has chosen an innovative charging concept: Onboard, the Audi RS Q e-tron is also the remarkably TFSI engine. It is part of the energy converter that charges the high voltage battery while driving. Since the internal combustion engine is used effectively between 4,500 and 6,000 revolutions per minute, the consumption is well below 200 grams per kWh.
The driveline in the Audi RS Q e-tron is electric. The front and rear axles are both equipped with an engine-generator unit (MGU) taken from the current Audi e-tron FE07. The MGU was developed by Audi Sport for the Formula E season 2021 and has only received minor modifications to be used in the Dakar Rally.
A third MGU, with an identical design, is part of the range extender and is used to recharge the high-voltage battery while driving. Energy is also recovered during braking. The battery weighs about 370 kilos and has a capacity of about 50 kWh.
"The battery is also an in-house development, which we have realized together with a partner," says Stefan Dreyer, development manager for motorsport projects within Audi Sport. "As engineers, we basically see development potential in every detail. But when it comes to the driveline, we have already achieved a system effect of over 97 % in Formula E. The situation is completely different for battery and energy management. This is where the greatest development potential is in electric power in general. What we learn from the extremely challenging Dakar project will be transferred to future production models. As always, we also work closely in this project with our colleagues from the series development."
The maximum system power is 500 kW. How much of this can be used during the Dakar Rally is still being determined by the organizer. Electric operation offers many benefits. The electric motors can be controlled highly precisely and thus provide good driveability. In addition, the braking energy can be recovered.
The Audi RS Q e-tron only needs a front derailleur. The front and rear axles are, as usual in electric cars, not mechanically connected to each other. The software developed by Audi distributes the torque between the axles and creates a freely configurable centre differential, which saves weight and space that would otherwise be needed for a propeller shaft and mechanical differential.
Visually, the Audi RS Q e-tron also differs significantly from conventionally powered Dakar prototypes. "The car looks futuristic and has many design elements that are typical of Audi," says Juan Manuel Diaz, Team Leader for Motorsport Design at Audi.
The Dakar Rally 2022 is carried out together with Q Motorsport. "Audi has always chosen new and brave paths in racing, but I think this is one of the most complex vehicles I have ever seen," says team manager Sven Quandt. "The electric driveline means that many different systems have to communicate with each other. In addition to reliability, which is number one during the Dakar Rally, it is our biggest challenge in the coming months."
Quandt compares Audi's Dakar project to the first lunar landing: "At that time, engineers did not really know what to expect. It's similar to us. If we reach the finish line in the first Dakar Rally, it will already be a success. "
