Working on the Battery Structure, EMS and BMS!
At the TU Delft Solar Boat Team, I am part of the Electronics Department. This is the department of the team which focuses on the generation, storage and transition of energy to the vital parts of the boat. Furthermore, we focus on Data Acquisition: the control of sensors, the storage and interpretation of the data.
I am working on the battery and everything else that is involved with this: the Energy Management System and the Battery Management System. Our battery may nog contain more than 1.5 kWh. The lithium-ion cells are made from lithium-ion batteries. This contains more energy per kilo than the batteries you have at home. In addition to the cells themselves, a structure is also needed to keep the battery together and to keep the circuit closed. This year, the battery has thirteen cells in parallel and twelve in series. To connect them, nickel plates are used this year because this can be spot-welded, unlike copper. The structure itself is made of plastic, polycarbonate to be more exact. This is of course not what you expect directly for electronics, but this is also necessary to get a working battery.
The Energy Management System (EMS) controls the entire electrical system in the boat. The EMS determines which components are switched on and off, and therefore communicates with all electrical components in the boat, such as all the sensors but also the motor controller.
The Battery Management System (BMS) ensures that the battery is not too unbalanced. After discharging and charging the battery, not all modules are discharged or charged to the same voltage. In order to get the battery back into balance, the BMS discharges the modules with the highest voltage until the voltage through the battery is the same.
In addition to what I do at the Solar Boat Team, I also follow courses. I follow two per quarter and although the combination of the two can sometimes become very busy, it is certainly possible to do. The most important thing is to have a good planning and spend time efficiently. In this way, it is possible to do the tasks for the team, to keep up with your studies and possible save time for sports and other things.