Icy temperatures of minus 35 degrees Celsius. Snow-covered streets. Frozen lakes. We are in northern Sweden in Arjeplog, Lapland, not far from the polar circle. This is where Daimler tests every new model under extreme conditions. Serenia Haussecker, development engineer in the Mercedes-Benz Vans eDrive projects, and Patrick Stolz, responsible for overall vehicle testing of the new Mercedes-Benz EQC, tell us about their experience on their test run in the snow.
Please introduce yourself briefly.
Haussecker: I am 28 years old and a development and software engineer in the Mercedes-Benz Vans eDrive projects. I did my Bachelor of Engineering in Energy Management at Heilbronn University. I then completed my Master of Science in Environmental and Energy Management at the University of Trier in 2017. I first came into contact with Daimler in 2012 during my internship in fuel cell stack development and then later on while writing my thesis. There, I dealt with research and development on alternative drive types.
Stolz: I studied Technology Management at the University of Stuttgart. Before joining the “EQC overall vehicle testing team”, I worked in the “electric vehicles project management team” at Daimler.
Describe your job in a few words.
Haussecker: In our department we look after vehicle development and additional mobility services with suitable charging infrastructure including fleet management. In addition, we work with various specialist units in a swarm-like organization with start-up character. This mix of office work and working directly on the vehicle at tests or in the workshops makes the work day very diverse.
Stolz: We are responsible for the overall vehicle and make sure that all individual components will be integrated. Our goal: We give character to the vehicle and put top performance on the road. Before we actually go on the first test drive, I am busy in planning the test drives, choosing the driving profile, instructing the drivers, defining the test program and doing the logistics. So it's a long road. But it's worth it!
Both of you have just returned from the winter test in Sweden. Mercedes-Benz purpose-built a test center in Arjeplog. What can be tested here?
Stolz: A number of things can be tested here, including a hill start on an incline of up to 20 percent, vehicle handling on a specially designed handling course and test routes on pure ice. We test the functionality of the control systems (e.g. ESP, ASR), brake and accelerator measurements on different surfaces, the heat-up characteristics in the interior and defrosting characteristics. And we do all of this at extremely cold temperatures.
What exactly does your job entail in these tests? What do you do on site?
Haussecker: It is important that the eVito as a battery-electric vehicle functions reliably at extremely low temperatures, too. Therefore, my job in Sweden was the low-temperature validation of the charging components and the software. To this end, numerous safety tests were carried out in order to test the overall package of hardware and software. Are the batteries' current and voltage limits being adhered to? Are there error responses? I oversee the tests and collate the results so that we can transfer the findings to our series production. In addition, we have ensured that the customer is offered sufficient range with comfortable climate control even in difficult conditions.
Mr. Stolz, aside from the prototypes of the battery-electric Mercedes-Benz EQC, you also had the GLC F-CELL, a fuel-cell vehicle, with you. What was the special aspect here?
Stolz: In the case of electric vehicles, there are a number of additional drive-specific tests that have been specifically developed for the new drive technologies. New challenges in terms of an electric vehicle include the output of an electric motor on a cold start and with a completely cold battery, the range in customer operation, the handling of the charging cables, the pre-entry climate control and the operational strategy including recuperation. In addition, we have the cold-start characteristics of a fuel cell (stack) in the GLC F-CELL. A special feature of the this vehicle type is that the interior heating is operated via the waste heat from the fuel cell system. In the GLC F-CELL this means that significantly less additional energy is required in comparison to battery-electric vehicles. Overall, the tests went very well.
And how did the eVito do?
Haussecker: We were very satisfied with our eVito. It successfully completed the endurance tests even under extreme weather conditions. With an installed battery capacity of 41.4 kWh and a real range of 100 km even in unfavorable weather conditions, our van offers our customers the best requisites for inner-city delivery, trade and passenger transport.
How is the developer team put together in a low-temperature test like this? What job profiles are behind it?
Stolz: The teams are extremely heterogeneous in composition. We have colleagues from various special units on site, from engineers and software developers, to mechanics and electronics specialists as well as night-time endurance test drivers, so that the tests can be prolonged into the night.
Haussecker: Our test team was made up of 38 experts and collaboration worked very well. The cold and dark work days did not stop us all from embarking on a hike in the snow, and we got to experience the northern lights up close.
In all honesty, what kind of clothing do you pack for a trip like this to extremely low temperatures?
Stolz: Dressing in layers is very helpful here. While it may be -35°C outside, in the workshops and vehicles it heats up quite quickly.
Haussecker: Thankfully we can bring a somewhat bigger suitcase with us and of course we have work clothes as well. Although we might look like a blue Michelin man in our work clothes, the heavy overalls keep us warm even in Sweden's minus temperatures. Otherwise, long underpants and the usual winter attire are a must.