Mercedes-Benz EQC performs summer tests
Spain is the last stage of the Mercedes-Benz EQC on its path to reaching series production maturity. Part of the high-temperature testing of this vehicle takes place on the Iberian Peninsula, and there is no chance to relax. Following successful winter testing, the EQC is required to complete an extensive testing program in the blazing heat of summer, with temperatures of up to 50° Celsius. Special attention is paid to aspects that are very demanding for electric cars, that is, air conditioning and recharging; as well as cooling the battery, propulsion system and control units in extreme heat conditions. Classic criteria such as driving dynamics and ride comfort are also evaluated in additional, rigorous tests.
“With the home stretch in sight, we can now complete another extremely demanding testing program with our pre-production vehicles,” said Michael Kelz, EQC Chief Engineer. “After successfully completing the winter resistance tests, at minus 35 degrees Celsius, we are confident that the heat tests will confirm that we met the plan to start series production.”
The number one challenge is dry heat. Because while an electric car battery “simply” loses power in the cold, exposure to excessive heat carries a risk of damage to the battery. The optimal management of these physical characteristics is the objective of the extreme tests carried out in Spain. One of the main focuses of attention is on the battery cooling circuit. For example: how does it cope with high power requirements? How does an almost fully charged battery respond to an additional charge? What influence does heat have on the vehicle's range? Battery drain tests, that is, tests in which the battery is completely discharged of power, are also part of this evaluation program.
Another aspect is the cooling of the air inside the vehicle, both during a trip and before it, since pre-climatization is an important factor for the comfort of users. This is when you answer questions such as “Is the indicated time enough for pre-climatization?” and “Is the calculated autonomy correct when the interior temperature is taken into account?” Additionally, the loudness of individual components, such as the air conditioning compressor, is specifically examined at elevated temperatures.
Fine dust is also a particular challenge in testing in Spain, as technicians want to know where and on what components it can settle and whether the sealing job works in practice.
Different countries present different circumstances, a topic that plays a very important role in Mercedes-Benz's testing program. The key question is: is the international operability of each individual system assured? We give some examples: Are traffic signs of different designs recognized? Are different tolls reliably recognized? Do the assistance systems camera correctly detect speed limits? All of these questions are also examined by the developers during their busy weeks of testing in Spain.
The demanding testing program at Mercedes-Benz
The systematic validation of complete vehicles is among the exhaustive measures in the development process of each Mercedes-Benz model series. This helps us verify the highest quality standards.
Before a new product goes into production, the complete vehicle must reach the maturity level set by Mercedes-Benz, and this process takes place in several stages. The first step is preliminary digital design and simulation. Certain individual components are then validated, either on dynamometers or in test vehicles. This tests and validates, for example, the durability of a drivetrain connection or individual parts of the suspension axles.
Testing: absolutely essential before launching a new vehicle
- Completely digital. Digital testing covers all key areas of vehicle development: from simulation and verification of vehicle construction, impacts, aerodynamics, ride and handling, NVH (noise, vibration and rigidity) and weight testing, to those of fuel consumption and operational autonomy.
- From the computer screen to the dyno to the road. Despite all the advantages of digital testing in terms of speed, data availability and efficiency, no vehicle enters series production without an extensive real-world test cycle. The focus is on the long-term durability of components, such as that of major assemblies, which is tested on a dynamometer; in addition to the functional tests of the complete vehicle under different climatic conditions, which are carried out on the road. In the case of the EQC, of course, special attention is paid to the electric drive system and the battery. These items are tested and approved according to extremely strict Mercedes-Benz standards.
- One third/two thirds. With a 35/65 percent ratio between digital and real-world tests, Mercedes-Benz combines the best of both worlds to benefit its characteristic high-quality standards.
- It's all a question of proportion. The acoustics of an electric car also play a special role: unlike a car with a combustion engine, there is hardly any noise from the drive system. This makes sounds like tire rolling or wind noise more prominent. When it comes to these requirements, the engineers benefit from their long experience in NVH testing.
- Almost 200. This is the number of prototypes and pre-series vehicles that are built for a vehicle test program.
- Several hundred. Before being approved for production, the vehicle must be tested and validated by numerous individuals from different development departments. Several hundred experts are involved in the tests. From the specialized departments, which approve its components and modules, to the resistance testing of the complete vehicle.
- About four years. In the case of the EQC, the total development time is around four years.
- Three winters and three summers. Over three winters and three summers, the EQC is being subjected to extreme temperature conditions, between minus 35º and 50º Celsius.
- A true cosmopolitan. Before reaching the market in numerous countries around the world, the EQC will have undergone extensive testing in Germany, Finland, Sweden, Spain, Italy, Dubai, South Africa, the United States and China.
