SRC-Based Two-Cell Li-ion Battery Buck Converter for De-ripple Power Operation

Sinusoidal ripple current (SRC) can improve Li-ion battery charging/discharging efficiency, rate, and cycle life. However, the ripple power caused by the SRC charging/discharging operation will reduce the converter’s efficiency and lifespan of the filtering components. To address these issues, an SRC-based two-cell Li-ion battery buck converter topology is proposed in this paper. It is the first attempt to sustain SRC operation without compromising converter power quality. The proposed converter distinguishes itself from the conventional Buck converters by incorporating a two-cell time-division multiplexing function, preventing the ripple current from flowing through the passive components. A dedicated time-division multiplexing modulation technique has been devised specifically for two-cell Li-ion batteries. Simulation results have been provided to verify the SRC and de-ripple functionalities.