Design and implementing of a novel resonant switched-capacitor converter for improving balancing speed of lithium-ion battery cells

Active topologies based on the Switched-Capacitor converters (SCC) are used for battery cell balancing because they eliminate magnetic elements effectively. In addition, these converters have easier implementation, integration capability, and reduced size. Despite of all these benefits, SCCs suffer from some disadvantages such as increased number of active switches, edge current, low balancing speed, and high switching losses. In this paper, a chain resonant SCC is introduced which can realize soft switching condition at zero current, limiting edge current, and increasing the balancing speed to overcome the problems of SCCs. To confirm the operation of the proposed converter, a chain resonant SCC with the capacity of 2150 mAh, the nominal voltage of 3.6 V, and the switching frequency of 50 kHz is simulated in MATLAB/SIMULINK, and implemented in the laboratory. The simulation and implementation results of the converter approve the correctness of the converter performance.