Okay, Elon, this is where it gets serious. The Mercedes-Benz Vision EQXX is what folks who’ve been building automobiles for more than a century can do when they turn the might of their huge research and development budgets entirely to thinking about designing and engineering a better electric vehicle.
Mercedes-Benz says the Vision EQXX will travel more than 620 miles on a single charge. But here’s the thing: Unlike the current range kings of the EV world such as the Lucid Air Grand Touring (516 miles, according to the EPA) and the Tesla Model S Long Range (405, per the EPA) Mercedes says it’ll do so with a smaller battery pack—just under 100 kWh in capacity versus the Lucid’s 118-kWh pack and the Tesla’s 100-kWh pack.
That’s better than 6.2 miles per kWh, which would make the EQXX a third more efficient than the Lucid and 55 percent more efficient than the Tesla. This Mercedes changes the conversation around EVs away from today’s almost total focus on range as a function of battery capacity. In the EQXX, range is a function of a holistic approach to vehicle efficiency.
And Mercedes believes there are good practical reasons for taking that approach: “It would have been easy to just use a big battery to get the range,” says EQXX drivetrain engineer Tim Wölfel. “But we wanted that range in a compact vehicle.”
The car’s long tail flatters to deceive: The Vision EQXX is more compact than it looks. Its 110.2-inch wheelbase is exactly 3.0 inches shorter than that of a Tesla Model 3, and is right between those of the current A-Class and C-Class sedans. And while the battery has almost the same capacity as the 100-kWh unit in the 126.4-inch-wheelbase Mercedes-Benz EQS, it’s half the size and weighs 30 percent less.
True, the Mercedes-Benz Vision EQXX is a concept. But it’s not vaporware. Like key Mercedes concepts of the past, such as the Experimental Safety vehicles of the 1970s, this fully street-legal prototype—Mercedes says it meets all current crash safety regulations—previews cutting-edge technologies and techniques that are ultimately destined to appear on production Mercedes models.
And it’s not just the car that’s efficient: A new digitally led design and engineering process saw the EQXX go from idea to road ready in just 18 months, bringing together expertise from the company’s Formula 1 and Formula E race engineering groups, its research department, prototyping specialists, and the production development team.
The Vision EQXX may be one of the most consequential concept cars of the early 21st century. Here’s why.
The Vision EQXX is powered by a single 200-hp electric motor mounted at the rear of the car and driving the rear wheels. The motor is based on the eATS unit that currently powers the compact EQA hatch and the newly launched EQB SUV, but it has been extensively reworked with the help of engineers from the Mercedes-AMG High Performance Powertrain (HPP) facility in Brixworth, England.
HPP, which designs and builds the fiendishly complex and highly efficient Mercedes Formula 1 powertrains, worked on every element of the EQXX drivetrain to reduce energy consumption and losses through system design, material selection, lubrication, and heat management. HPP also designed the EQXX’s power inverter, and the power electronics unit is the same one HPP helped develop for the Mercedes-AMG Project ONE hypercar.
“The motorsport guys count every joule of energy,” says Tim Wölfel, explaining that the EQXX’s drivetrain is 95 percent efficient. In other words, 95 percent of the energy sent from the battery gets to the driving wheels.
To reduce its size and weight, the EQXX’s battery pack dispenses with the conventional method of packing cells into separate enclosed modules, and has a lightweight top cover made from sugarcane waste reinforced with carbon fiber, a materials technology used in Formula 1. Weighing under 1100 pounds, the EQXX’s pack has an energy density of more than 200 Wh/kg.
Mercedes says the high energy density comes in part from the chemistry of the anodes, which have a higher silicon content and an advanced composition that means they can hold considerably more energy than commonly used anodes. The battery also has active cell balancing, which means power is drawn evenly from all cells. The EQXX system is very high voltage—more than 900V, well above the industry standard of 400V and even the 800V used in the Porsche Taycan.
The battery is only passively cooled, by the airflow under the car. How practical is that? “We want to find out,” says Wölfel, disarmingly reinforcing the idea the EQXX is a proper working concept, not a show car. “What we are thinking is that each battery cell heats itself, and if we know the cell well, we can control the temperature of the cell. A lot of resources are being put into this. We have to find out what is the best state of charge.”
Mercedes engineers have calculated that on the average long-distance drive, 20 percent of the energy stored in an electric vehicle’s battery will be consumed overcoming rolling resistance, and 18 percent by losses in the drivetrain and other vehicle systems. The rest—62 percent—will be consumed simply by pushing the vehicle through the air. That simple stat is the reason the EQXX has a claimed drag coefficient of just 0.18.
In profile and plan view, the EQXX has the classic teardrop shape of extreme wind cheaters such as GM’s groundbreaking EV1 and the Volkswagen XL1 hypermiler, cars both referenced by Mercedes engineers, along with the three-pointed star’s own 1938 540K Streamliner, the C111-III concept of the 1970s, and the Concept IAA unveiled at the 2015 Frankfurt Show, all of which boasted stated drag coefficients of 0.19 or 0.18. To get that shape, the rear track is two inches narrower than the front, and the cabin tapers dramatically above the car’s voluptuous hips.
At the front, air is carefully directed under the car, where a shutter system allows extra airflow to pass over a cooling plate for the electric motor if needed. Air is also directed around the front wheels to form a curtain and help keep the flow attached to the side of the car to reduce drag. The long tail helps reduce wasteful turbulence in the car’s wake, with an active rear diffuser that lowers and extends at about 40 mph to help keep the speed of the air coming from under the car equal to that streaming off the sides and top.
Mercedes says the ultrahigh-strength steel used in the EQXX’s body structure offers excellent occupant protection in the event of a crash, while keeping weight to a minimum. The doors are made from a hybrid of carbon- and fiberglass-reinforced plastics with aluminium reinforcements. A new polyamide foam reinforces the lower edge of the door and optimizes energy absorption in a side collision. The roof is covered with solar panels.
The most innovative bits of the EQXX’s body are the things you can’t see, like the large cast aluminum structure that extends from the rear floor and provides mounting points for the rear suspension and the motor. This casting is made using a patented process that creates a structure that mimics the load and strength paths of natural organisms, reducing excess material to a minimum. As a result, there isn’t a single straight line or flat surface on the part. The process, dubbed Bionicast, was also used to create the front shock tower domes of the EQS.
As the Bionicast process eliminates material from anywhere it’s not needed while preserving structural integrity, the rear inner fenders are full of large holes. To fill them, Mercedes uses a sustainable plastic substitute developed by an Israeli startup called UBQ Materials; it’s made from typical landfill trash such as food and garden waste as well as mixed plastics, cardboard, and even diapers. The combination of the Bionicast process and UBQ patches can reduce the weight of large structural castings by 15 to 20 percent, according to Mercedes.
EVs, even high-performance ones like Porsche’s Taycan Turbo S, aren’t usually hard on their brakes, despite their weight, because a lot of braking is done using regeneration via the motor(s). The EQXX is thus fitted with coated aluminum brake rotors rather than iron or carbon-composite units. The aluminum rotors save 29 pounds over conventional iron units, and are considerably less expensive to make than carbon-composite ones.
Corvette fans will be delighted to learn the EQXX has fiberglass-reinforced plastic rear springs. Unlike the simple Corvette leaf, however, the EQXX springs look like four-inch-wide, half-inch-thick strips of plastic folded into a serpentine shape. Developed in partnership with German supplier Rheinmetall Automotive, these strange looking pieces are said to be much lighter than conventional coil springs.
Behind the EQXX’s beautifully styled flush wheel covers are ultralight 20-inch forged magnesium wheels. The wheels are shod with specially developed Bridgestone Turanza tires that are also lightweight and have ultra-low rolling resistance.
Once you get past the wins in terms of aerodynamics, powertrain optimization, and weight reduction, the efficiency devil is in the details. And the EQXX brims with clever technologies and features that are designed to help the car extract the most performance from every joule of energy it consumes.
The 117 solar panels on the roof of the EQXX feed into a 12V system that powers many of the car’s ancillaries. On a good day, says Mercedes, the system will lower the draw on the 900V system enough to deliver a 15-mile bump in range. Meanwhile, sensors around the car monitor the airflow so the EQXX can calculate the positive or negative impact of changes in wind direction on energy consumption. Combining all that data with detailed terrain and traffic information, the EQXX will constantly calculate and display a speed that delivers maximum efficiency.
The curved 8K screen that stretches 47.2 inches between the A-pillars makes the most of the EQXX’s crisp and sparkling game-engine-powered graphics, including a realtime 3D navigation display. The mini-LED backlit screen features more than 3000 local dimming zones, which means it only consumes power as and when specific parts of the screen are in use. The EQXX has conventional external rearview mirrors because engineers concluded a camera system like that used on Audi’s e-tron in global markets would consume too much energy.
The EQXX interior is visually spectacular. Some parts, such as the steering wheel, gear selector, and wiper and turn signal stalks are existing Mercedes parts. The car also features the same touch-sensitive seat-adjustment system as on the latest generation Mercedes models. More important, though, the big infotainment screen looks a part of the overall design, not added in.
But what’s more impressive is that almost all the fabrics and leathers and carpeting are made of either plant-based organic materials or recycled plastics. The door pulls, for example, are made from a vegan-certified biofabricated silk. The seats are trimmed in an animal-free leather made from pulverized cactus fibers combined with a bio-based polyurethane. The seat cushions’ details are covered in a vegan leather alternative made from mycelium, which is the underground rootlike structure of mushrooms.
The carpets are made from 100 percent bamboo fiber. Recycled PET bottles used in a shimmering textile enhance the floor area and door trim, while an artificial suede made from 38 percent recycled PET has been used to create a wraparound effect linking the upper edge of the one-piece screen with the doors and headliner.
Neuro what? Neuromorphic computing is a form of information processing whose hardware runs so-called spiking neural networks. These artificial neural networks mimic natural neural networks, firing only when certain thresholds are reached. Mercedes says the system reduces energy consumption “by orders of magnitude.”
Mercedes engineers worked with California-based artificial-intelligence developer BrainChip to create systems based on the company’s Akida hardware and software. Among other things, the technology makes the “Hey, Mercedes” voice control system in the EQXX five to ten times more efficient than conventional voice control.
Mercedes acknowledges that while neuromorphic computing is still in its infancy, it says similar systems will be available in a variety of consumer products within a few years. And when applied at scale throughout an electric vehicle, neuromorphic computing has the potential to significantly reduce the energy needed to run the latest artificial intelligence technologies.
ARE YOU READY, ELON?
The Mercedes-Benz Vision EQXX is an intellectual and technological tour de force, a fully functional prototype that explores the outer limits of electric vehicle efficiency, connectivity, and production feasibility. Mercedes-Benz says the EQXX also showcases its transformation into a software-driven company whose goal is to be the leader in electric vehicles.
“The Vision EQXX is how we imagine the future of electric cars,” says Mercedes-Benz chairman Ola Källenius. “It underlines where our entire company is headed: We will build the world’s most desirable electric cars.”
The gloves are coming off, Elon. Is Tesla ready for the fight?
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