Real-Time Battery Equalization Circuitry for Series Battery Packs with Inverse-Excitation Type Multi-directional DC-DC Converter

This research work focuses on the management of battery packs and proposes an automatic battery capacity equalization circuitry along with its implementation method. The circuitry employs a flyback multi-directional DC-DC converter as the main equalization circuitry to facilitate the transfer of electric energy for equalization. A relay is utilized to establish the connection between the batteries requiring equalization and the flyback multi-directional DC-DC converter. Additionally, a microprocessor is employed for battery state detection, equalization control, and other related tasks. The proposed automatic battery capacity equalization circuitry operates by cyclically detecting the capacity of each battery using a Microprogrammed Control Unit (MCU). The two batteries with the highest and lowest capacities are connected to the ends of the flyback multi-directional DC-DC converter. The high-capacity battery is then used as an input to perform equalizing charging, either in a constant current or constant voltage mode, on the low-capacity battery until its capacity reaches the average value of the battery pack. Compared to conventional battery equalization circuitry, the automatic battery capacity equalization circuitry offers simplified equalization processes, strong controllability, high speed, and high efficiency.