Entry: Mercedes Vision EQXX, radiant electricity

Imagine an electric car that can connect Brest to Lyon on a single charge, ie almost 1,000 km without compromising on speed, comfort and above all driving pleasure.

Not possible? Mercedes-Benz is convinced of the opposite and has developed the Vision EQXX concept to prove it. This rear-wheel drive sedan serves as a showcase for the electric drive technologies, aerodynamic developments and lightweight construction that the brand is aiming for in future production models.

Unlike most concepts, which are usually simple rolling models, this one is road legal. Better: It promises a yield of 10kWh/100km at legal highway speeds, versus 15.6kWh/100km for the excellent (but heavy) EQS.

With a 100 kWh battery integrated in the flat floor, this results in a theoretical range of over 1,000 kilometers. For comparison: The rear-wheel drive EQE 350 has a range of 650 km with a 90.6 kWh battery.

The 900V unit is equipped with the latest CATL lithium-ion cells. With their silicon anode, they are said to deliver an energy density of up to 400 Wh per liter and are therefore significantly more energy-efficient than the cells used in the batteries of existing EQ electric models. It is also claimed to be 50% smaller and 30% lighter than today’s batteries.

Mercedes has already shown the potential of the Vision EQXX on two development drives, most recently from Stuttgart to Goodwood over 1,202 km without recharging. However, this was achieved by a team of highly skilled test pilots with real-time access to all information generated by a trunk full of data loggers and in constant radio contact with engineers at the Mercedes base in Germany.

Despite this, Mercedes is so confident in the Vision EQXX’s ability to achieve high efficiency targets with any driver behind the wheel that they just tossed me the key and told me to take a drive and see for myself what’s possible. It’s not just a low-speed tour, but a journey along a series of winding roads in and around the huge research and development center in Immendingen.

Before I slip into the driver’s seat and hit the start button, a quick recap of what’s inside this teardrop-style body. With various active spoilers, including an elaborate diffuser that unfolds from the lower edge of the rear bumper at high speed, the EQXX achieves a record drag coefficient of 0.17.

The starting point for the Vision EQXX was a prototype called Emma. Built last year, it was used to test the packaging and durability of the concept's high-tech powertrain and the various software programs that make it possible to achieve such extraordinary savings numbers. — The starting point for the Vision EQXX was a prototype called Emma. Built last year, it was used to test the packaging and durability of the concept’s high-tech powertrain and the various software programs that make it possible to achieve such extraordinary savings numbers.

The car itself is mostly bespoke, including the platform, which sports a distant cousin of the Mercedes Modular Architecture (MMA) used on cars like the EQC sedan expected in 2024-2025.

At 4977mm long, 1870mm wide and just 1350mm high, the Vision EQXX is 226mm longer, 50mm wider and 105mm lower than the current C-Class. Its wheelbase is 40 mm shorter at 2800 mm.

The teardrop shape contributes to an unprecedented Cx of 0.17 and impressive energy efficiency. Thanks to a high-strength steel body structure, carbon fiber doors and aluminum brake discs, among other weight-saving measures, the package weighs just 1755 kg.

On the engine side, the compact synchronous unit with 241 hp integrated in the rear axle was developed jointly by the German Mercedes engineering team and the HPP division (High Performance Powertrain) in Brixworth. The rear wheels are driven via a one-speed gearbox.

The driver’s door can be opened wide, which makes it easier to get on board despite the relatively low height. The clamshell front seats, with rather firm upholstery but little lateral support, are mounted fairly low but without dedicated footrests, while the pedals are placed fairly high, creating a very sporty driving position. Rear visibility is non-existent as an array of solar panels covers the entire roof and space that would normally be devoted to the rear window.

Entry: Mercedes Vision EQXX, radiant electricity

The dashboard is quite low and houses a 110 cm wide curved 8K digital display panel. The touchscreen unit houses a whole host of menus and data, including wind direction, which is measured by three tiny sensors on the front. Everything is very elegant, but it’s not just for show. Everything works as you would expect from a regular Mercedes.

To go forward, pull the Direct Shift stick toward P and squeeze the throttle, just like any stock EQ model. We find the typical smoothness of electric motors as soon as they run. The performance is good right off the bat and feels rather snappy under load up to the governed top speed of 140 km/h.

But with Mercedes engineers remotely following my every move, now is not the time to test the machine’s accelerations. Instead, we settle into a circuit to see how close we can come to saving the in-house drivers.

The digital display provides real-time consumption, which we try to keep as low as possible. The original plan was to drive without air conditioning to save energy, but with temperatures reaching 30 degrees in the midday sun we don’t think that’s such a good idea.

All functions run on the large touchscreen, just like on board a production car.

At typical highway speeds, the Vision EQXX is perfectly cultivated. In addition to the damped character of the electric motor, there are almost no aerodynamic disturbances. This is where the rear diffuser unfolds to lengthen the body, reduce underbody turbulence and provide more longitudinal stability. There are four regenerative braking modes, activated via steering wheel-mounted paddles.

In operation, you rarely need to physically brake, even on slower corners. At the other end, the Vision EQXX rolls freely and without noticeable mechanical resistance over impressive distances, and this without any power consumption, also thanks to its low-rolling-resistance 185/65 R20 Bridgestone tires specially developed for the concept. The constant juggling between the different modes increases and decreases consumption, which proves stimulating and entertaining.

From a driver’s perspective, there’s a lot to enjoy. It starts with the arrangement of the drive wheels. The steering is surprisingly precise, albeit rather heavy, while the battery’s in-floor placement keeps the center of gravity low for the benefit of manoeuvrability.

The suspension is heavily damped to ensure a consistent ride height and the best possible aerodynamics. On the typically smooth German roads we drive on, the handling is quite acceptable. It's firm but never stiff. — The suspension is heavily damped to ensure a consistent ride height and the best possible aerodynamics. On the typically smooth German roads we drive on, the handling is quite acceptable. It’s firm but never stiff.

With excellent forward visibility and a relatively narrow width, the Vision EQXX is easy to place on the road, where it proves to be very flexible. Then we notice that the concept already has more than 16,000 km on the clock, proving that it is not just a parlor animal. In fact, the EQXX feels perfectly at home on a variety of different roads, at low and high speeds.

At the moment, it’s hard to say how much car technology will go into Mercedes’ next electric models. But as a demonstration of intent, it’s very impressive.

The longer you drive it, the more convincing it becomes. We think it’s mature enough to go into production now. Such thoughts, however, ignore the costs associated with their creation…

At the end of our test drive, the data logger shows applications of throttle, brakes, steering angle, operating temperature and more. However, that’s the economic number we’re looking for.

And to our great surprise, despite air conditioning and passenger transport, we perform better than Mercedes at 12 km per kWh. Brest-Lyon on one charge? No problem. In fact, according to our calculations, you can go even further…