Fundamental monitoring tasks (cell voltage and temperature measurement), as well as passive balancing, lie on the lowest layer of the platform, i.e., the cell. Charge transfer between cells (for charge equalization), dynamic battery reconfiguration, and thermal management belong to the intermediate layer, namely the module. Finally, current sensing, battery protection (by a main switch or contactor), and more advanced functions, such as SOC and SOH estimation, are mapped to the uppermost layer of the platform. The pack layer provides communication with the external systems, such as the vehicle management unit.