This bachelor’s thesis focuses on thermal behaviour of cylindrical battery cells. The introductory section familiarizes the reader with fundamental terminology, operating principles, and the internal structure of the cell. The subsequent section examines heat generation, the influence of temperature on performance characteristics, and available methods of thermal management. The following chapter provides an analysis of existing experimental solutions, serving as a methodological foundation for the measurements conducted in this study. The experimental part comprises measurements aimed at recording temperature increases during battery operation, namely during the charging and discharging cycles. The LFP technology proved to be the most thermally stable and homogeneous, exhibiting demonstrably lower thermal inhomogeneity than the NMC cells. While the average thermal inhomogeneity across all conducted experiments was 0.27 °C for the LFP technology, this temperature difference reached 0.42 °C for the NMC MH1 cell. In terms of overall thermal behavior,  the dependence of both the maximum and average relative temperature rise on the operating current was demonstrated. With increasing current, the values of both variables generally increased. In this regard, the MH1 cell proved to be the most thermally stressed, reaching the highest relative temperature rise during both charging and discharging, namely 8.45 °C and 10.88 °C, respectively.