The VISION EQXX from Mercedes-Benz has now taken on the roads of Europe and
has demonstrated its outstanding range and efficiency. Traveling from
Sindelfingen across the Swiss Alps and Northern Italy, to its destination of
Cassis on the Côte d’Azur, it effortlessly covered more than 1,000 km (621
miles) in everyday traffic, on a single battery charge. The journey started
in cold and rainy conditions, and was undertaken at regular road speeds,
including prolonged fast-lane cruising at up to 87 mph on the German
autobahn and near the speed limit elsewhere. The battery’s state of charge
on arrival was around 15 percent, amounting to a remaining range of around
140 kilometers (87 miles), and the average consumption was a record-breaking
low of 8.7 kWh per 100 kilometers (7.1 kWh per 62 miles).
The VISION EQXX has thus taken electric vehicle efficiency to a whole new
level – in real-life conditions and with independent proof. The
long-distance drive was completed with the charging socket sealed and
accompanied by an independent expert from certification body TÜV Süd. This
officially confirms the effectiveness of the new Mercedes-Benz development
approach – thinking holistically about efficiency from the drivetrain to
aerodynamics and beyond, down to the smallest detail, as well as working
with even greater interfunctional collaboration and with external partners.
This new blueprint for automotive engineering has delivered a new benchmark
for electric vehicle efficiency and range, and the technology in the VISION
EQXX will be deployed in upcoming series-production Mercedes vehicles.
“We did it! Powering through more than 1,000 kilometers with ease on a
single battery charge and a consumption of only 8.7 kWh/100 km (7.1 kWh per
62 miles) in real-world traffic conditions. The VISION EQXX is the most
efficient Mercedes ever built. The technology program behind it marks a
milestone in the development of electric vehicles. It underpins our
strategic aim to ‘Lead in Electric’,” says Ola Källenius, Chairman of the
Board of Management of Mercedes-Benz Group AG.
Ready for the longest road trip since the invention of electric mobility
There’s a reason why road trips have been a cultural touchstone for decades,
telling stories from the highway in books, movies and music. The road trip
defines freedom, individuality, the very spirit of the automobile and the
passing world. Stick a pin in the map – and drive.
The journey to electric mobility is also a road trip; as exhilarating as it
is challenging, and as unknown as it is certain. For Mercedes-Benz, it is a
journey with a clear goal – maximum efficiency through innovation. The
VISION EQXX is the product of a holistic approach with innovations in all
technical areas that have an impact on energy consumption. “With our
successful road trip to the South of France, we’ve shown that efficiency is
the new currency. And this success also clearly speaks for our new
collaborative development process, incorporating many learnings from the
Mercedes-AMG F1 team and its cutting-edge expertise in electric powertrains.
The VISION EQXX is the result of a comprehensive program that provides a
blueprint for the future of automotive engineering. Many of the innovative
developments are already being integrated into production, some of them in
the next generation of modular architecture for compact and midsize
Mercedes-Benz vehicles. And the journey continues. With the VISION EQXX, we
will keep testing the limits of what’s possible,” says Markus Schäfer,
Member of the Board of Management of Mercedes-Benz Group AG, Chief
Technology Officer responsible for Development and Purchasing.
Challenging route profile and varying weather conditions
The VISION EQXX is packed with innovations. This software-defined research
prototype is part of a far- reaching technology program that combines the
latest digital technology with Mercedes’ pioneering spirit, the agility of a
start-up and the speed of Formula 1. The mission in developing the VISION
EQXX was to break through technological barriers across the board. To show
what is electrically “feasible”, the research vehicle completed a one-day
road trip across several European borders: from Germany to Switzerland, on
to Italy, past Milan and finally to its destination, the port town of Cassis
near Marseille in the South of France.
The route profile – from motorway to mountain passes, including roadworks –
and the weather conditions presented the VISION EQXX with a wide variety of
challenges. Departing from the Sindelfingen R&D center near Stuttgart in
cold conditions, temperatures from start to finish ranged from 3 to 18
degrees Celsius. North of the Alps there was light rain and further south a
gentle headwind blew in the sunshine. The various sections of the route
helped document the effect of the many efficiency measures.
An excerpt from the trip log:
Up to 140 km/h (87 mph) on the highway – low drag and rolling resistance pay
off
The first leg from Sindelfingen to the north-eastern border of Switzerland
runs along Autobahn 81. At times, the VISION EQXX sliced through the wind at
speeds of up to 140 km/h (87 mph). With its low cd value of 0.17, it gives
the wind virtually nothing to grab hold of. This world-beating figure for a
road-legal vehicle results from the intelligent interaction of many
individual measures. It starts with the basic shape of the body, cradling
the smooth-surfaced dome of the greenhouse as it flows elegantly like a
water droplet towards the rear. Equally beneficial to the aerodynamics are
the small frontal area of 2.12 m² and the reduced rear track. Because this
is 2 inches narrower than at the front, the rear wheels roll in the
slipstream of the front wheels. The active rear diffuser, which
automatically deploys at 37 mph, provides better airflow and thus
contributes significantly to the reduced drag.
The technology vehicle gains further efficiency benefits from its tires,
with their extremely low rolling- resistance rating of 4.7. Bridgestone
developed these specifically for the VISION EQXX in partnership with
Mercedes-Benz. By way of comparison, the current EU tire label requires a
figure of 6.5 for the top rating in Class A. The EQS uses tires with a
rolling resistance of 5.9, which is significantly lower. With the VISION
EQXX, Mercedes-Benz is now going one step further. A striking feature is the
size of the new tires. The dimensions 185/65 R 20 97 T mean they have a
large diameter and a narrow tread. The specialist Turanza Eco tires combine
two innovative Bridgestone technologies that enable a higher range: ENLITEN
technology reduces both rolling resistance and weight by up to 20 percent.
The ologic technology reduces tire deformation while driving, in part
through a more tensioned belt section. In addition, the transition from the
tire to the wheel rim was optimized in cooperation with the Mercedes-Benz
aerodynamics team.
Over the mountains – the lightweight dividend
The VISION EQXX’s special features also include its carefully
thought-through lightweight construction, which has a particularly positive
effect on uphill climbs. Any keen cyclist knows why it’s always the same
type of rider out in front on mountain stages. The heavier, more muscular
sprinters are always staring at the taillights of the wiry featherweights on
the uphill treks. The decisive factor is the power-to-weight ratio. It’s not
about sheer performance in the sense of “faster; higher; further” but about
endurance and lower energy consumption.
This is exactly what the VISION EQXX demonstrates impressively on the
approach to the Gotthard Tunnel heading for Italy. On the section between
Amsteg and Göschenen, there’s a 9-mile uphill stretch with an incline of up
to five percent. It is here, where every gram of extra weight eats up
energy, that the VISION EQXX scores sustainable points with its unladen
weight of only 3,869 lbs.
The lightweight design concept of the VISION EQXX is comprehensive – from
the materials used to innovative bionic structures that deliver a favorable
power-to-weight ratio. Examples of this are the sustainable carbon-
fiber-sugar composite material used for the upper part of the battery, which
is also used in Formula 1, and the BIONEQXXTM rear floor, manufactured using
an aluminum casting process. The light metal structural component replaces a
much heavier assembly of several interconnected parts. It has gaps in places
where structural strength is not required, thus saving material. This
innovative design approach results in a weight saving of up to 20 percent
compared to a conventionally manufactured component.
A large part of the weight efficiency is also due to the dedicated electric
chassis with lightweight F1 subframe and aluminum brake discs. Another is
the battery. At 100 kWh, the power storage unit developed specifically for
the VISION EQXX has almost the same amount of energy as the battery of the
EQS, which is already a global benchmark among electric cars currently on
the market. However, it has 50 percent less volume and is 30 percent
lighter. The outcome is that the compact battery, measuring just 200 x 126 x
11 cm (79 x 50 x 4 in), is also comparatively light at 1,091 lbs and fits in
a compact car. The electric drive was developed in cooperation with the
experts from Mercedes-AMG Petronas F1 Team.
Back down the hill – recuperation is the name of the game
After the Gotthard Tunnel, the road goes downhill for a very long way. This
is where the VISION EQXX makes the most of the situation in its own way.
While the golden rule of the professional cyclist is to go full throttle
downhill to make up time, the VISION EQXX does the unthinkable and
regenerates its energy reserves. In electric cars, this is called
recuperation, the recovery of braking energy. In this discipline, too, the
VISION EQXX sets new standards thanks to its highly efficient electric
powertrain.
The VISION EQXX can use the recuperation effect on any type of gradient and
during every braking maneuver, thus extending its range. A positive side
effect of this electric braking is that the mechanical brakes are barely
used. This makes it possible for the first time to use new types of aluminum
brake discs that weigh significantly less than their steel counterparts.
Solar roof – energy refresh in sunny Italy
The VISION EQXX gets an energy refresh around midday in the Po Valley near
Milan – not at the charging station, but via its fixed solar roof. The 117
solar cells feed the 12-volt battery, which supplies power to auxiliary
consumers such as the navigation system. The added value is measurable
through the load this removes from the high-voltage battery, displayed by
the onboard computer. Overall, the solar booster increases the range by more
than two percent – which adds up to a good 25 kilometers (16 miles) on a
journey of over 1,000 kilometers (621 miles).
Innovative eATS – powerful, frugal, enduring
The electric drive unit in the VISION EQXX – consisting of the electric
motor, transmission and power electronics – was developed together with the
F1 specialists at HPP, and has a peak output of 180 kW. Thanks to the torque
available from the first rev of the motor and the very low aerodynamic and
rolling resistance of the VISION EQXX, its full potential is barely tapped
during the entire trip. Other factors become more important than top
performance. Just like the battery, the electric drive unit is compact,
lightweight and highly efficient. Its average efficiency in this application
is 95%. That means 95% of the energy from the battery ends up at the wheels.
This goes hand-in-hand with further efficiency benefits such as the
reduction of losses in the drivetrain. The engineers at Mercedes-Benz have
succeeded in reducing the total losses in the drivetrain (motor, inverter
and transmission) by 44% compared to an e-drive that is not based on this
project. This makes a big difference for the bottom line, with one percent
more efficiency bringing two percent more range. This effect is further
amplified by the battery of the VISION EQXX, thanks to its remarkable energy
density of almost 400 Wh/l and particularly high operating voltage of more
than 900 volts. And on the topic of high voltage: The VISION EQXX marks the
first use of this technology, which proves itself throughout the entire
journey. Without a single problem such as line overheating, everything is
well under control. There are further efficiencies from the active cell
balancing, this ensures that energy is drawn evenly from the cells during
the journey, which increases the usable energy and thus the range even more.
Efficient thermal management system – passive powertrain cooling is all it
takes
Since the electric drivetrain generates minimal heat waste thanks to its
high efficiency, passive cooling is sufficient throughout the journey. The
cooling plate in the underbody uses the airflow to ensure even cooling. This
aerodynamically highly efficient solution increases the range by 20
kilometers (12 miles), while the cd value remains unchanged at a low 0.17.
Even on the ascent to the Gotthard Tunnel, the air shutters remain closed.
The air control system would only open an additional airpath if there was an
increased demand for cooling the electric drive or for climate control
inside the cabin on hot days or if the heat pump was running on cold days.
The airpath then connects the high-pressure zone at the front of the vehicle
with the low-pressure zones along the top of the hood. This enables highly
efficient thermal management with minimal air resistance. With the shutters
open, the cd value would increase by only seven points (0.007).
Efficiency assistant – actively helping to save energy
Whether e-drive or combustion engine, the amount of energy a motor consumes
in practice ultimately depends a great deal on driving style. In
Switzerland, Italy and France, “pedal to the metal” is not an option, thanks
to speed limits and attentive law-enforcement officers. However, the VISION
EQXX also proves to be an intelligent sidekick, assisting the driver like a
co-pilot with tips on the best possible driving style. The efficiency
assistant provides information on energy flow, battery status, topography
and even the direction and intensity of wind and sun.
The UI/UX features an all-new, one-piece display that spans the entire width
of the interior. Elements of the user interface support seamless interaction
between the driver and the vehicle. These include Artificial Intelligence
(AI) that mimics the way the human brain works. In the VISION EQXX,
Mercedes-Benz takes a radically new UI/UX approach. A game engine takes UI
graphics to a whole new level. The UI shows how real- time graphics open up
new digital possibilities by reacting instantly to the driver’s needs and
bringing the real world into the vehicle.
Finale in France – crossing the finish line with around 140 kilometers of
remaining range
Shortly before crossing the finish line in Cassis, the VISION EQXX gathered
energy once more through recuperation. After 11 hours and 32 minutes of
driving time, it ended its 1,008-kilometer (626 miles) road trip with a
remaining range of around 140 kilometers (87 miles). This means it could
have set off again for a jaunt along the Mediterranean coastline without
recharging.
The VISION EQXX has unequivocally proven the real-world potential of
outstanding efficiency for electric vehicles. This first road trip to Cassis
is a watershed moment on a much bigger journey that is far from over.
There’s a lot more to come.
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