Prototype features 2.0-liter inline-four TFSI engine acting as a generator, and two electric motors for its drivetrain producing 671 hp.
Testing in sands of Morocco allows the team to evaluate battery performance in high-temperatures, well above those experienced in Formula E with similar tech.
Audi is going electric in the Dakar Rally in a matter of months, and there's not that much time left for major changes before the grueling event gets going in January, but just enough for some fine tuning. The automaker is fielding the RS Q e-tron in the prototype class, eager to showcase its electric vehicle technology before an international audience and in conditions that will also seem very foreign to modern EV owners.
That's why this month Audi has brought the RS Q e-tron to Morocco for two weeks of testing, in conditions that be even harsher than in Saudi Arabia in January. The rally car has already completed testing in Spain and Germany, ahead of a more serious outing intended to push it out of its comfort zone, with Audi bringing all three driver crews to the North African country.
Audi has developed a high-voltage battery specifically for the Dakar Rally, with optimum temperature management being one of the keys, just like in Formula E.
"We expect much lower temperatures at the Dakar Rally," says Andreas Roos. "Nevertheless, we deliberately went to Morocco to test our concept under the most extreme conditions. Components such as the [motor-generator unit] MGU, for example, were basically not developed for use in such high ambient temperatures, but the drivetrain and other components were also pushed to their limits or even beyond by the heat. The insights we gained in Morocco are invaluable, but they also show us that we still have a lot to do before the Dakar Rally and there is not much time left."
Of course, Audi already has plenty of experience on its side heading into Dakar, as the three prototypes will be piloted by Dakar veterans Stéphane Peterhansel, Carlos Sainz, and Mattias Ekström. Audi brought co-drivers Edouard Boulanger, Lucas Cruz, and Emil Bergkvist to Morocco as well for this round of testing.
"The thermometer climbed to well over 40 degrees Celsius at times," said Sven Quandt, team principal of Q Motorsport. "Sandstorms also hampered the testing. In addition, as expected, some new problems arose in the high temperatures, which repeatedly caused interruptions to the testing and needed to be solved before the next test."
The daily distances of the Dakar stages themselves, being up to 800 kilometers (497 miles) in length, certainly pose their own challenges, with the RS Q e-tron featuring an entire TFSI engine under the skin to recharge itself while driving, with the engine set to operate between 4500 and 6000 rpm to consume as little gasoline as possible. That's right: There are no charging stations in the middle of the Saudi desert.
The prototype features a motor-generator unit (MGU) at each axle, one that actually has very few modifications from the version used in the Audi e-tron FE07 Formula E car. But the prototype also has a third MGU just for the energy converter that recharges the battery thanks to the TFSI engine. The battery itself is relatively small one as far as EVs go—just around 50 kW—and weighs 815 pounds. This buys the prototype 500 kW, or 670 hp.
"The battery is also a proprietary development that we have realized together with a partner," said Stefan Dreyer, head of development at Audi Sport for motorsport projects. "As engineers, we basically see development potential in every component. But in terms of the drivetrain system, we have already achieved a system efficiency of over 97 percent in Formula E. There's not much more room for improvement. The situation is quite different with the battery and energy management. This is where the greatest development potential lies in electromobility in general. What we learn from the extremely challenging Dakar project will flow into future production models. As always, we are also working closely with our colleagues from road car development on this project."
If a TFSI engine and three electric motors sound like a heavy group, the tradeoff is that the RS Q e-tron features just one forward gear—there's no bulky transmission—and the axles themselves aren't connected by propshafts at all. Instead, Audi has created what it calls a virtual center differential, saving quite a bit of space and weight in the process, with software deciding upon torque distribution between the axles.
On the other hand, a lot of the other Dakar competitors will be far less complex mechanically, an advantage for the two-week rally.
"Audi has always chosen new and bold paths in racing, but I think this is one of the most complex cars that I have ever seen," team principal Sven Quandt said back in July. "The electric drivetrain means that a lot of different systems have to communicate with each other. Besides reliability, which is paramount in the Dakar Rally, that's our biggest challenge in the coming months."