Mercedes-Benz Vision EQXX Concept First Drive: Sampling the Future

I did not win the efficiency contest here in Immendingen, Germany, home of the sprawling Test Center of Mercedes-Benz even though I had a handicap: the supremely slippery Mercedes-Benz Vision EQXX, a drivable concept car that can travel more than 1,200 km (745 miles) on a single charge.

The problem was not the car, it was me. I could not help busting out of the recommended conservative driving habits to gun it when the speed limits on the handling course allowed, which hurt my score, as did the need for manual braking when a speed limit was momentarily exceeded, prompting a warning. The benchmark was 7.9 miles per kWh; I recorded only 6.4 kWh of average consumption over the 10-mile course. On the plus side, after each burst of acceleration, I used the most aggressive of the four settings for regenerative braking and racked up more than three times the extra energy and range of the benchmark driver.

Which is to say, the beauty of the EQXX is that it can be fun, with a mighty torque pull, as well as efficient—I still recorded a single-digit consumption figure—so best of both worlds.

And that is good because this Vision concept is the future of Mercedes EVs. The learnings and stylings will show up in new vehicles coming in 2025 and beyond from the new Mercedes Modular Architecture or MMA. The EQXX is a street-legal prototype and the only one of its kind in the world. At 110.2 inches, it is a compact car, roughly the same wheelbase as the Mercedes-Benz EQB.

Its impressive range, beating the Lucid Air Grand Touring's 516 miles and the Tesla Model S Long Range at 405 miles per EPA, is attributable to a number of factors. The EQXX has a 100-kWH battery pack, similar to the one in the Mercedes-Benz EQS large sedan, but in the EQXX concept the unit is half the size and weighs 30 percent less, the cells are packaged differently and it has a carbon fiber top cover. The anodes use more silicon and hold more energy. While the rest of the Mercedes EV lineup have a 400-volt system, and some competitors have 800V, the EQXX system is more than 900V.

Stumbling onto the Teardrop Shape

The design team came up with the car's teardrop shape with the rear track two inches narrower than the front, a tapered cabin, and a long tail with an active diffuser which extends almost 8 inches. "We didn't set out to create this shape, we found it," Malte Sievers, project manager for the Vision EQXX tells us.

The result: a claimed drag coefficient of 0.17—more streamlined than a football—making the EQXX the most efficient model Mercedes, or perhaps anyone, has built. It could become a car for the ages as 0.17 will be hard to beat, physics is physics, says Sievers. And this slippery missile could never be built if it had to accommodate an internal combustion engine. "The whole thing falls apart," he says. "It shows the capability EVs brings to the industry."

Engineers say 62 percent of the EQXX's efficiency is from aerodynamics; meaning every change to aero affects everything else by 62 percent. You can make changes to rolling resistance, for example, but your efforts will never impact more than 20 percent of the total efficiency. And everything else amounts to an 18 percent impact. The team looked at every part to see if it was necessary and if so, how to make it light, efficient, and not heat up. The cooling plate underneath allows the car to be cooled by airflow and the overall efficiency means there is little to cool.

The summation of all the engineering efforts is a car where 95 percent of the energy sent from the battery makes its way to the wheels. For reference, the EQS sends 90 percent of its energy to the wheel well, which means the team had to make the EQXX twice as efficient.

First Outsiders to Drive the Mercedes-Benz EQXX

We were part of a media program that let non-Mercedes people drive the Vision EQXX for the first time. To date, only Mercedes employees have put it through its paces. That includes two road trips, the first April 5 from Singelfingen, Germany, to Cassis in northern Italy, 1,008 km (626 miles) and using 8.7 kWh/100 km or 7.1 miles per kWh, with 140 km (87 miles) left at the finish. The second run, June 21-22, was from Stuttgart to Silverstone in France, a distance of 1,202 km (747 miles) in summer heat requiring the air conditioning to run for 11 hours. Average consumption was 8.3 kWh/100 km or 7.5 miles/kWh, and it included 11 laps on the track when the car reached Silverstone to empty the remaining energy.

To work out the bugs, the team created a test mule by squeezing a 100-kW battery, DC/DC converter and DC charging controls, battery management system, other aspects of the EQXX powertrain, as well as testing equipment, into a Mercedes-Benz EQB. The mule is known as EMMA (the MMA for Mercedes Modular Architecture). EMMA made the Sindelfingen to Cassis trip first in a test run with its share of breakdowns, a learning curve that proved to be a total success as the EQXX did not have a single mishap in either of its long-distance tests.

We drove EMMA, who was a little clunky as the suspension was not adapted for the weighty equipment added or the fact that most of it bears down on the rear axle, throwing off the balance.

Then we hopped in the EQXX which was much quieter, balanced, nimble, and downright supple by comparison, riding on Ultralight 20-inch forged magnesium wheels with Bridgestone Turanza tires that are also lightweight and have ultra-low-rolling resistance. The car cornered nice and flat, the suspension was not challenged by the course, but neither did it stumble.

Impressive Regenerative Braking

Both cars have one-pedal driving with four degrees of regenerative braking—mild, two aggressive settings, and the option to have no reclamation at all, which works infinitely better on the EQXX. On one long straight in EMMA, we turned off regen and saw our speed drop about 9 mph within seconds. In the EQXX the speed never dropped at all.

Manual braking was harsher in EMMA, it was less grabby in the EQXX, but engineers wince if a foot ever touched that pedal because it means energy is being lost. We used the most aggressive regen setting for most of the EQXX drive; it was highly effective without being too harsh.

There is a satisfying weight to the EQXX's steering and the vehicle is not flighty at all. Input and response are nicely married. Acceleration on the 21-minute lap was not neck-snapping but the car picked up speed quicky and smoothly. It was easy to exceed the course's varying speed limits that were being closely monitored.

The big takeaway is that it felt like a production model more so than a concept.

Attempting the Impossible

The EQXX prototype was pulled together in 18 months, a project launched with a request in June 2020 from the board of management to build an electric vehicle capable of driving 1,000 km (621 miles) on a single charge. Almost all the teams involved worked to achieve the seemingly impossible target of 10 kWh/100 km, Sievers said. The car relied on expertise from Mercedes' Formula 1 and Formula E race engineering groups as well as the research department and production development team.

There are 117 heavy solar panels on the roof that send energy into a 12V system that powers many of the car's ancillaries which equates to a roughly 25-km (15-mile) bump in range. Engineers say the energy gains from the panels are greater than the losses due to the extra weight.

You cannot see out the glass of the back window; nor are there cameras for the rearview mirror—they would consume too much energy.

It all adds up to a highly efficient EQXX that exceeded the mandate.

Loving the Luxury Interior

The beautiful navy and white interior of the EQXX is serene and modern without looking too sci-fi or clinically cold, with sustainable vegan materials that look high end. There are 47.5 inches of curved OLED screen, perfect for using the real-time 3D navigation display—but only when absolutely necessary. The mini LEDs that backlight and dim the screen make for crackling crisp graphics. Dimming zones save power by not illuminating the parts of the screen not in use; there is zero energy consumption when the LEDs shut themselves off.

Mercedes provides eco guidance. The car knows the route conditions of the trip programmed into the nav system and tells the driver to speed up or slow down to be more efficient. The driver can look at data to show energy usage, solar energy produced, air pressure and wind direction, and forecast how much energy the trip will require. Almost ready for production is an Intelligent Avator to suggest movies to watch or restaurants to stop at, saving the driver from scrolling through menus on the screen and using energy.

They are tools I clearly need. Said the engineer who tried to keep a straight face as he analyzed the data spikes in my EQXX run: "I think you had fun." Then he confirmed Mercedes would not be hiring me anytime soon for their EV testing.