Our battery pack consists out of 288 cells. When the gas pedal is pressed down current flows through the motor but while breaking energy is recuperated by letting our motor work as generator. This recuperation allows us to use 30% less battery cells and still complete a full endurance race!
Our battery pack is in 96s3p setup, this means 96 cells are in series with each 3 cell in parallel. This setup allows us to provide sufficient power of 80kW to the motors but in such a way that the current is low. As a result we have less losses and lower electromagnetic interference.
To connect the parallel cells we use the special welding technique, namely ultrasonic welding. By using ultrasonic vibrations and a high compressive force the cell taps are welded together. The advantages of this technique is that no filler material is needed and thus results in a clean weld. Our partner Rodgers Corporation made this possible though we had to go to Switzerland for the welding process.
Last week our potential drivers had the opportunity to show their potential during a driving course at the driving school Jesco in Puurs. After a short briefing about what was going to happen during the day, it was time for real action. The group of ten potential drivers was divided in smaller subgroups of just two people. Each group got a different car to do a few test laps. After a few tries it was time to switch cars, because every car has his own specific dynamic behaviour. The first exercise of the day was to avoid a sudden obstacle at a certain speed. At first sight this seemed very easy, but the rear tires of each car was equipped with slick tires. So it was a lot harder to achieve this first exercise than first thought. The potential drivers were seriously under pressure to bring this first simple exercise to a successful ending. Every time someone succeeded in this exercise, it was time to raise the speed of the exercise. So the difficulty level of the exercise was raised time after time.