Solar-Roofed Mercedes EQXX Concept EV Crushes Range Anxiety

By Ben McKimm - News

Published: 6 Jan 2022, Last Updated: 18 Sept 2023

The worst part about owning an EV? Charging it. Not only do you have to partake in these strange conversations with other EV drivers about why they decided to remove the hubcaps on their Tesla Model 3, but its time consuming and quite frankly, we’d rather not. And while the idea of replacing the roof of a car with solar panels has always been the obvious answer, you’re more likely to see a few panels strapped to the roof of a van than supporting a concept EV ‘sports-sedan’.

Like everything in the automotive industry, these things are always easier said than done. Enter Mercedes-Benz.

Mercedes-Benz has done it (of course they have) and although the panels are yet to greatly impact range, its a step in the right direction, combine it with a super slippery exterior and highly efficient drive motors and you’ve got one of the most innovative EVs we’ve seen to date. The name is VISION EQXX and it invites innovation to the space in ways we have always longed. In short, internal digital simulations in real-life traffic conditions showcase this vehicles ability to exceed 1,000 kilometres on a single charge with an energy consumption of less than 10 kWh per 100 kilometres (efficiency of more than 6 miles per kWh). To put that in perspective a Tesla Model 3 Long Range currently manages just 16 kWh per 100 km.

VISION EQXX: Key Specifications

Battery energy content, usable	<100kWh
Max. system voltage	>900Volts
Energy consumption	<10kWh/100 km
cd value	0.17
Max. power output	~150kW
Wheelbase	280cm
Gross vehicle weight	~1,750kg

Image: Mercedes-Benz

How Did Mercedes Achieve 1000km of Range?

The brand refers to it as ‘ripping up the engineering rule book’ but we prefer to look at it as a deep dive into what makes automotive innovation so exciting. Instead of simply increasing the size of the batteries (and weight) the EQXX introduces Formula 1 and Formula E technology to the drawing board, and the result is an exciting yet completely realistic way forward for electric vehicle technology. Here’s the breakdown.

Electric Drive system designed and built in-house achieves benchmark efficiency of 95% battery to wheels.
The battery pack in the VISION EQXX holds almost 100 kWh of energy.
Has 50% less volume and is 30% lighter than the already benchmark pack in EQS.
More than 1,000 km (over 620 miles) on a single charge on public roads puts an end to range anxiety.
Exterior designers and aerodynamicists delivered a benchmark drag coefficient of cd 0.17.

Less Power, More Efficiency

Most surprisingly is the lack of big power from the motor. While it is a highly efficient power train, Mercedes seems to understand that the idea of ‘fast EV’ is slowly dying amongst the average buyer who’s no longer interested in 0-100km/h sprints and cares more about range. Here, efficiency and thus the range is the aim of the game, with 95% efficiency from the motor to the wheel – that’s 60% greater than the average internal combustion motor. The power electronics unit is based on the one in the upcoming Mercedes-AMG Project ONE hypercar.

“We worked on every part of the system to reduce energy consumption and losses through system design, material selection, lubrication and heat management. And our fantastic simulation tools helped us find out quickly what works and what doesn’t,” explained Eva Greiner, chief engineer of the electric drive system at Mercedes-Benz.

The electric drive unit in the VISION EQXX is a dedicated unit consisting of the electric motor, transmission and power electronics featuring a new generation of silicon carbides.

Less Battery, More Density

Rather than simply increasing the size of the battery, Mercedes-Benz and the HPP team developed a completely new battery pack for the VISION EQXX, achieving a remarkable energy density of close to 400 Wh/l. This figure is what made it possible to fit a battery pack with just under 100 kWh of usable energy into the compact dimensions of the VISION EQXX.

“The battery has almost the same amount of energy as the EQS but is half the size and 30% lighter. The battery management system and power electronics have been designed with an absolute focus on reducing losses. In achieving this efficiency milestone, we learnt a lot that will flow into future development programmes,” said Adam Allsopp, Advanced Technology Director from HPP.

A bunch of technical chemistry that is far outside the realm of explanation and the result is a battery cell of 900 volts. While there’s no telling if this level of voltage will ever reach any form of production model the team was able to gather a great deal of valuable data and is currently assessing the potential benefits and implications for future series production. Overall, the battery weighs around 495 kilograms.

Solar-Powered Roof

Ooook, now for the coolest bit. The electric system that powers many of the ancillaries in the VISION EQXX draws additional energy from 117 solar cells on the roof. In ‘ideal conditions’ – solar roof owners will cringe at those words – on a single day this panel can add up to 25 km of range on long-distance journeys. Yeah, it ain’t much! But it’s something!

The panel powers a climate blower, the lights, the infotainment system and other ancillaries. Most excitingly, Mercedes-Benz and its partners are working towards using solar power to charge the high-voltage system, too.

Image: Mercedes-Benz

A Culmination of Efficiency

Almost every piece of the Mercedes-Benz VISION EQXX has been worked over to maximise efficiency. It’s an engineering masterpiece when it comes to technical innovation, and if this is what the future of EV’s looks like, a few petrolheads like ourselves might have some engineering and technical specs to look forward to. We haven’t even talked about the interior, but we think photos do it justice anyway, see below.

For more information about the VISION EQXX, check out the link below.

Check it out