Mercedes-Benz EQXX Designed to Squeeze Maximum Juice

NICE, France – The Mercedes-Benz Vision EQXX is a road car of the future that exists today. Its mission? To deliver the longest possible range using the least amount of electricity.

After two years of conception and development, the fully operational sedan was put to the test earlier this month on a development drive from Mercedes-Benz’s development center in Stuttgart, Germany, to the company’s design studio in Nice, France – a distance of 626 miles (1,008 km), which it achieved on a single charge of its 100-kWh battery at an average speed of 54.3 mph (87.4 km/h).

In the process, the EQXX returned average consumption of 7.1 miles/kWh (11.4 km/kWh). What’s more, it is claimed to have arrived at its destination with over 87 miles (140 km) of remaining range.

To put this into perspective, the recently introduced EQE sedan, which uses a 90.6-kWh battery, boasts an official WLTP consumption figure of between 3.8 and 3.3 miles/kWh (6.1 and 5.3 km/kWh), giving it a range of 410 miles (660 km).

They’re impressive figures. But they’re not half as interesting as seeing the Vision EQXX up close for the first time.

Rather than simply adopting a teardrop shape with faired-in wheels for maximum aerodynamic potential with compromises in packaging (see General Motors’ EV1 and Volkswagen’s XL1), Mercedes-Benz has delivered a car that is conceived to offer similar levels of accommodation and everyday practicality as a regular production car.

The front takes on a sportscar-like appearance, with a low leading edge, a short hood, shapely fenders and large wheelhouses. The signature Mercedes-Benz grille is replaced by a star graphic incorporated into the front bumper, while the digital LED headlamps are conjoined by a full-width LED light bar.

The cabin tapers toward the rear (pictured, below), giving the Vision EQXX a heavily shouldered appearance over the rear wheels. Unusually, the rear track is 1.9 ins. (48 mm) narrower than the front.

Mercedes EQXX Vision side view

The 20-in. wheels both front and rear are completely blanked off to minimize wind buffeting within the wheelhouses. They’re shod with 185/65 profile Bridgestone Turanza Eco tires whose compound and profile have been developed specifically for the car.

At the rear, a full-width light graphic runs across the trailing edge of the trunklid and down along the sides. But the real attraction here is the diffuser, which extends outward to optimize the aerodynamics.   

The upshot of all this is a drag coefficient of 0.17, the lowest ever achieved by Mercedes-Benz on a road-legal car. As a point of reference, its most aerodynamic production road car, the rear-wheel-drive EQS450+, has a drag coefficient of 0.20.

At 196.0 ins. (4,978 mm) long, 73.6-ins. (1,869 mm) wide and just 53.1 ins. (1,349 mm) tall, the Vision EQXX is 1.2 ins. (30 mm) longer, 3.5 ins. (89 mm) narrower and 6.2 ins. (157 mm) lower than the EQE. It also rides on a wheelbase that is a considerable 12.2 ins. (310 mm) shorter than Mercedes-Benz’s newest electric-powered sedan at 110.2 ins. (2,799 mm).

The basis for the new concept is a unique rear-wheel drive platform. It is claimed to incorporate elements of the MMA (Mercedes Modular Architecture) structure to be used by production models from 2024. A lithium-ion battery weighing 1,091 lbs. (495 kg) is mounted within the floorpan. Described as being “around 100-kWh,” it uses the latest CTP (cell-to-pack) silicon anode technology from Chinese supplier CATL and operates at 900V. 

Power comes by way of an electric motor developed between Mercedes-Benz’s German-based engineering team and its HPP (High Performance Powertrain) division located in Brixworth, U.K. Nestled within the rear axle, it is rated at 188 hp.  

Built with carbon fiber and other lightweight materials as well as aluminum brake discs, the Vision EQXX concept weighs a claimed 3,869-lb. (1,755 kg).

All four doors open wide to provide a sizeable aperture and welcome ease of entry. The front seats, boasting firm cushioning but minimum support, are mounted low, and the floor is flat.

The view ahead through the heavily angled windscreen is excellent, while the view directly behind is nonexistent because an array of 117 solar cells covers the area that otherwise would be taken by a rear window.  

The dashboard is set low, contributing to a snug feel suggested by the narrow dimensions. It supports both a multifunction steering wheel and 47.5-in. (121-cm) -wide curved digital display. The heavy rake of the windshield places the header uncomfortably close to your forehead, but otherwise, there’s a lot to like about the highly stylized, leather-lined interior.

Friedemann Flache, one of four engineers nominated to drive the Mercedes-Benz concept, took Wards on a test drive in Nice.

“It is very straightforward,” he says. “It doesn’t demand a particularly special driving style or anything like that, though to get the best out of it, to really strive for maximum efficiency and range, you have to anticipate situations well ahead.”    
On public roads around Nice and beyond, it is the imbibing smoothness and overall refinement of the Vision EQXX’s high-tech drivetrain that leaves the biggest initial impression. One-off engineering concepts rarely project such deep-seated engineering integrity, but this one feels entirely happy making progress along arterial roads.

When we get a clear run at higher speeds on the motorway, Flache calls up a menu to extend the rear diffuser and optimize the aerodynamics. All the while, he keeps a keen eye on the electric energy being used. “We try to keep it in a sweet spot of around 6.2 to 4.3 miles (10 to 6.9 km) per kWh,” he says.

Four levels of brake energy regeneration are activated via steering wheel-mounted paddles. Most of the time, the EQXX is engaged in D--. It provides strong deceleration when the throttle is lifted.

Despite the clear focus on efficiency, the rear-wheel-drive EQXX has a subtly sporting flavor. Drive is channeled through a single-speed gearbox. While the low-slung sedan clearly has the potential to extend well beyond it, top speed is limited to 87 mph (140 km/h) as an efficiency measure.

Ingenious, compelling and entertaining, the EQXX shows how electric cars are likely to progress in coming years. The good news is that with the sort of advances in aerodynamics, tire technology, construction techniques, electric motors and batteries it showcases, a realistic range of 600 miles (966 km) and more under real-world driving conditions on a single charge is achievable. Let’s just hope this also applies to models we all will be able to afford.

Mercedes Vision EQXX rear 3.4_0