In early April, a Mercedes-Benz VISION EQXX concept car was fully charged and sped out of the R&D center in Sindelfingen, Germany, through the drizzling Alps, through several European countries in 11 hours and 32 minutes to Cassis, France, on the Mediterranean coast. After driving 1008km, the vehicle still has 15% of the electricity left, and it can drive about 140km.
The test set a record for the lowest energy consumption ever recorded by Mercedes-Benz and demonstrated the enormous potential of electric vehicles for energy efficiency.
Different from the traditional working condition test, the VISION EQXX concept car is completely based on the daily car scene, and the driving route includes a variety of steep mountainous areas, from cold mountains to warmer plains, and the temperature spans 3-18 degrees Celsius. On the German highways, its speed (under the electronic speed limit) reaches the maximum speed limit standard of 140km/h, and the average speed of the whole journey reaches 87.4km/h, but the energy consumption per 100 km is only 8.7kWh.
How is such low energy consumption achieved? In addition to its ultra-high energy efficiency, what other innovations does this concept car have? Recently, EV Century interviewed Markus Sch fer, a member of the board of directors and chief technology officer of Mercedes-Benz Group AG, who is responsible for research and development and procurement.
Efficient "three electric" system and low wind resistance body
The Mercedes-Benz VISION EQXX concept car's first road endurance performance is perfect, almost the ceiling of the current energy efficiency of electric vehicles. Xue Fuming said that this is due to the use of a large number of technologies specially developed for electric vehicles on this concept car.
First of all, in terms of batteries. According to Xue Fuming, the special battery pack equipped with the VISION EQXX concept car has nearly 100kWh of energy, which is not very large compared with its final battery life performance.
Let's make a simple comparison. The official mileage of tesla model S dual motor version equipped with a 100kWh battery is 652km; the official mileage of THEO ET7 equipped with a 100kWh battery is 700km, and the official cruising range of THEO ET7 equipped with a 150kWh battery has reached 1000km. Moreover, the endurance of model S and ET7 is the mileage tested according to the official working condition method, and are not measured results.
Due to the use of new technologies, such as a 25% increase in the silicon content of the anode material, which greatly increases the energy density of the battery, the battery pack of the VISION EQXX concept car has an energy density of nearly 400Wh/L, which effectively reduces the weight and size of the battery pack, which is only 50% of the size of the new EQS battery pack and the weight is also reduced by 30%.
The battery pack packaging technology draws on the research and development ideas and design of formula 1 racing cars in F1, the BMS manages each cell separately, and the spacing between the cells during the package is also optimized.
Surprisingly, the concept car's battery pack features a new passive cooling system, and the thermal management system remains in good condition throughout the ride. In this regard, Xue Fuming explained that this can reduce the amount of power consumed when cooling or heating the battery pack, thus leaving more power for a longer journey. Many of the experiences and technologies learned from the VISION EQXX concept will be gradually applied to production models, reducing the need for active cooling systems for electric vehicles.
In terms of electric drive, the VISION EQXX concept car is equipped with an electric drive developed by Mercedes-Benz in cooperation with F1 experts, with a peak power of 180 kW and an efficiency of up to 95% (that is, 95% of the battery energy can be directly transmitted to the wheels). To maximize endurance, engineers managed to reduce the losses of their drivetrain (motors, inverters and transmissions) by 44 percent.
Coupled with the passive cooling system, the electric drivetrain produces almost no waste heat, and the heat dissipation plate installed on the vehicle baseplate can use the airflow to evenly cool the transmission system, which can help the vehicle increase the cruising range of about 20km.
In addition, 117 solar cells are installed on the roof of the car, which can charge the 12V battery system and then power the navigation and other systems. The solar charging system can increase the endurance by more than 2%, adding about 25km of additional cruising range to the vehicle in this test.
In terms of body design, the VISION EQXX concept car has a very smooth profile and smooth lines, the vehicle wind resistance coefficient is only 0.17Cd, when the speed reaches 60km/h, the active rear diffuser will automatically open the optimized airflow to reduce the impact of air resistance. Mercedes-Benz and Bridgestone have created an exclusive tire rolling resistance coefficient of only 4.7, which also optimizes energy efficiency.
Biomimicry and intelligent applications
In addition to the conventional means we are familiar with, the use of biomimicry to create a body structure and the latest intelligent technology has also played a role in improving energy efficiency.
Xue Fuming said that Mercedes-Benz has always paid great attention to drawing innovative inspiration from nature, and integrating the inspiration gained from nature into research and development and application, because the structure and evolution of nature over millions of years is the most efficient.
For example, engineers performed computer simulations and calculations based on biomimicry principles to optimize the body structure of the VISION EQXX concept car. The principle behind the beautiful lines and mesh structures we finally see is like bone growth, trying to use load-bearing materials in the load area, and minimizing the use of material and leaving gaps in the unloaded part. The principle of biomimicry reduces the use of body materials, which in turn reduces body weight.
In addition, engineers made extensive use of natural and sustainable materials to create the concept car, including high-performance sustainable biotech materials based on mushrooms, cacti and bamboo, and the battery top cover is made of sustainable carbon fiber-sugarcane composites derived from formula 1 racing.
In particular, this concept car also adopts human brain biomimicry technology, and its interactive execution is like the thinking process of the human brain, with "neuromorphic computing" for information processing of interactive instructions.
Compared with the traditional computer linear information processing method, "neuromorphic computing" is in a full-range interconnected state like the brain, and the components or modules responsible for data storage and data processing build a "pulse neural network", and the information instructions are encoded into different pulse signals scattered in the neural network for efficient synchronous processing, thereby greatly improving the thinking and reaction ability of the car machine, and the energy consumption is only triggered when the pulse signal appears, effectively reducing the information processing energy consumption of several orders of magnitude. For example, the "hot word perception" function of its MBUX mind-reading voice assistant is 5-10 times more efficient than that of traditional voice control.
Xue Fuming said that he hopes to use neuromorphic computing to interact with vehicles to achieve operation control in the future, rather than just relying on fingers touching the screen or sound commands.
In terms of intelligence, the VISION EQXX concept car is equipped with an innovative all-in-one screen design, extending from the A-pillar on the left to the A-pillar on the right, spanning the visual space of the main and passenger seats. During driving, the VISION EQXX Concept provides the most efficient driving style recommendations based on information such as energy flow, battery, terrain, and even the direction and intensity of wind and sun.
In addition, the game engine on the VISION EQXX concept car has reached a leading level in both computing power and graphics card, and has introduced many gaming experience-like functions in human-computer interaction.
Innovative technology mass production can be expected
From the invention of the automobile to the present, Mercedes-Benz has led the luxury car market with continuous technological innovation. "Just like the S-Class, the benchmark model for the luxury car market, we want to set a new benchmark in the field of pure electric vehicles, and it is with this in mind that the VISION EQXX concept was born, and our team of engineers has created an electric vehicle with the best energy efficiency and the most intelligence," says Xue Fuming.
From R&D to a series of certifications to final approvals to be legally launched, the VISION EQXX Concept took just 18 months (more than half the traditional R&D cycle). Xue Fuming said that this car is not a concept car or exhibition car in the traditional sense, but a prototype car for technological exploration. Some of these individual innovations will be available in production models in the next two years. By 2024, the car will be equipped with advanced technologies such as high-silicon battery technology, Mercedes-Benz's self-developed motor technology, HMI human-computer interaction system and display technology, sustainable materials, lightweight body construction and structural castings, which will be integrated into the MMA platform – a modular architecture designed for compact and medium-sized vehicles and successively applied to production models. By 2025, almost all of the technology on this concept car will be in mass production.
At the production end, Mercedes-Benz will also make full use of the experience in the production of fuel vehicles to create a perfect production closed loop. Xue Fuming introduced that from 2024, some of Mercedes-Benz's mass-produced new energy models will be equipped with mercedes-Benz independently developed motors. In terms of battery research and development, the battery management system and its software programming work have achieved independent research and development. Intelligent driver assistance systems and MB.OS are also promoting in-house research and development.
In order to achieve a closed loop, Mercedes-Benz has added 3,000 new software engineer-related positions around the world, and there are currently 10,000 software engineers in related fields, covering electric drive systems, advanced intelligent driver assistance, interconnection systems, cloud technology, etc.
At the same time, globally, Mercedes-Benz has achieved interconnection on 6 million vehicles, and car owners can achieve OTA upgrades. As the new launch models are equipped with the latest intelligent interconnection technology and continue to expand the number of vehicle-machine interconnection products, Mercedes-Benz will have more abundant data, so as to continuously optimize the system and introduce new product functions for customers.