Range and efficiency are set to define the electric era. Exceptional range will make electric cars suitable for every journey and help to increase overall adoption. Reduced battery size and weight will improve efficiency and Mercedes-Benz engineers are working to take range and efficiency to a new level.
The VISION EQXX includes advances across all elements of its electric drivetrain as well as the use of lightweight engineering and sustainable materials.
"The Mercedes-Benz VISION EQXX is how we imagine the future of electric cars. Just one-and-a-half years ago, we started this project leading to the most efficient Mercedes-Benz ever built - with an outstanding energy consumption of less than 10 kWh per 100 kilometers. It has a range of more than 1,000 kilometers2 (620 miles) on a single charge using a battery that would fit even into a compact vehicle. The VISION EQXX is an advanced car in so many dimensions - and it even looks stunning and futuristic. With that, it underlines where our entire company is headed: We will build the world"s most desirable electric cars." said Ola Källenius, Chairman of the Board of Management of Daimler AG and Mercedes-Benz AG. For further information see the IDTechEx report on Solar Vehicles 2021-2041 2nd Edition.
Based on internal digital simulations in real-life traffic conditions VISION EQXX will be capable of exceeding 1,000 kilometers (620 miles) on a single charge with an outstanding energy consumption of less than 10 kWh per 100 kilometers (efficiency of more than 6 miles per kWh). Rather than simply increasing the size of the battery, the team focused on maximizing long- distance efficiency. They pulled out all the stops in drivetrain efficiency, energy density, aerodynamics and lightweight design.
"The technology program behind the VISION EQXX will define and enable future Mercedes-Benz models and features," says Markus Schäfer, Member of the Board of Management of Daimler AG and Mercedes-Benz AG, Chief Technology Officer responsible for Development and Procurement. "As a halo car, the VISION EQXX firmly establishes Mercedes-Benz as the brand that pairs luxury with technology in the automotive world and beyond. And the way we developed it is as revolutionary as the vehicle itself. VISION EQXX has seen the best minds from our R&D centers work together with engineers from our Formula 1 and Formula E programs. They are proving that innovations from motorsport - where powertrains are already highly electrified - have immediate relevance for road car development. We are challenging current development processes with innovative spirit and outside-the-box thinking. This truly is the way forward."
VISION EQXX: main points at a glance
- EnergyWizard: Across the board, efficiency engineering achievements delivered an energy consumption of less than 10 kWh per 100 km (efficiency of more than 6 miles per kWh)
- ElectricDrive: Radical new system designed and built in-house - it achieves benchmark efficiency of 95% from battery to wheels
- RangeBuster: More than 1,000 km (over 620 miles) on a single charge on public roads
- EnergyDensity: The battery pack in the VISION EQXX holds almost 100 kWh of energy, yet has 50% less volume and is 30% lighter than the already benchmark pack in EQS.
- AeroChamp: Exterior designers and aerodynamicists delivered a benchmark drag coefficient of cd 0.175
- SustainableMaterials: Innovative recycled and plant-based materials remove waste from landfill and lower carbon footprint
- UpliftMindset: A team of Mercedes-Benz engineers worked with the world's fastest race lab at High Performance Powertrains (HPP) and Mercedes-Benz Grand Prix (MGP) to engineer a highly efficient and compact electric drivetrain and lightweight battery case
- BionicEngineering: Engineers used advanced digital tools to lower weight and reduce waste by removing excess material assisted by 3D printing
- RollingEfficiency: Ultra-low-rolling-resistance tires with optimized aerodynamic geometry combine with lightweight magnesium wheels for increased range
- BrakingLightly: Lightweight brake discs made from aluminum alloy are a great fit for the VISION EQXX and help keep weight down
- EfficiencyOnTheRoad: Electric-only chassis with lightweight F1 subframe brings racing efficiency to the road
- SolarPower: Ultra-thin roof panels feed the battery system for up to 25 km of extra range
- HumanMachineMerge: Intuitive and intelligent user interface and user experience with guidance and assistance for efficient driving
- FastTechProg: From clean sheet to on the road in just 18 months. The VISION EQXX is part of a technology program that can adapt innovative technologies for series production faster
- SoftwareDriven: Software-driven approach key to success in achieving efficiency goals and a rapid development process, including groundbreaking battery management system.
"The XX suffix augments the Mercedes-Benz brand with the X-factor of electric mobility that thinks beyond limitations, and an agile, X-divisional collaborative development approach," explains Markus Schäfer, "This enhances the breadth and depth of development skills within Mercedes-Benz AG with highly advanced digital tools as well as industry-leading expertise from a diverse array of partner companies, start- ups and institutions around the world."
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 benchmark 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.
"In effect, we fitted the energy of the EQS into the vehicle dimensions of a compact car," says Adam Allsopp, Advanced Technology Director from HPP. "The battery has almost the same amount of energy 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 learned a lot that will flow into future development programs."
The substantial increase in energy density comes in part from significant progress in the chemistry of the anodes. Their higher silicon content and advanced composition mean they can hold considerably more energy than commonly used anodes. Another feature that contributed to the energy density is the high level of integration in the battery pack. This platform, developed jointly by Mercedes-Benz R&D and HPP, created more room for cells and helped reduce the overall weight. The separate compartment for the electrical and electronic (EE) components, called the OneBox, likewise made more room for cells, with added benefits for installation and removal. The OneBox also incorporates novel safety devices with energy efficient operations that consume significantly less energy than the equivalent component in a production EV.
Increasing the voltage to more than 900 volts proved an extremely useful research tool for the development of the power electronics. 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.
Several more aspects of the battery design add to its exceptional efficiency. For instance, its lightweight lid was engineered jointly by Mercedes-AMG HPP and their chassis partners at Mercedes-Grand Prix. The lid is made from a unique, sustainable composite material derived from sugar-cane waste, reinforced with carbon fiber, as used in Formula 1. The battery also features active cell balancing, which means drawing the energy evenly from the cells while the car is driving - in effect, giving it greater stamina. Overall, the battery weighs around 1,091 lbs, including the OneBox.
The electric system that powers many of the ancillaries in the VISION EQXX draws additional energy from 117 solar cells on the roof. It was developed in collaboration with the Fraunhofer Institute for Solar Energy Systems ISE - Europe's largest solar energy research institute. The net result of reducing the energy drain on the high-voltage system is an increase in range. On a single day and under ideal conditions, this can add up to 25 km (15 miles) of range on long-distance journeys. The solar energy is stored in a lightweight lithium-iron-phosphate battery, which supplies a climate blower, the lights, the infotainment system and other ancillaries. Mercedes-Benz and its partners are working towards using solar power to charge the high-voltage system, too.
Source and top image: Mercedes-Benz