This master’s thesis addresses the challenges of voltage measurement and balancing in lithium-ion battery packs, a key technology in modern energy storage. As the number of series-connected cells increases, ensuring safe and efficient operation becomes increasingly complex, since cell-to-cell variations lead to voltage imbalance, reduced capacity, accelerated aging, and heightened safety risks. A multifunctional measurement system was developed, enabling controlled charge and discharge currents as well as simultaneous monitoring of individual cell voltages, while providing independent access to each cell without disassembling the pack. The advantages and limitations of passive and active balancing methods are presented: the former are simple and cost-effective but energetically inefficient, whereas the latter enable charge redistribution with significantly lower losses and added functionalities. As a practical solution, an active charge redistribution system based on buck–boost converters was designed, complemented by an innovative mechanical rotary switch that reduces the number of required converters and consumes no energy in standby. The results confirm that efficient systems for measurement, fault detection, and cell balancing can be achieved with simple yet well-designed solutions. Such systems also open opportunities for further development, including scaling to larger numbers of cells, designing regenerative converters, and improving overall efficiency and reliability. The thesis provides a comprehensive insight into battery pack management and contributes to the advancement of both laboratory and industrial applications.
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