Active balancing using the DC2100B-C and DC2100B-D module

The propulsion system is undoubtedly the most important component of an electric vehicle. It includes the electric motor, the battery, and the associated electronic control. In terms of cost, the battery accounts for approximately 50% of the initial vehicle cost. The battery is accompanied by a management system that performs various functions, including cell balancing. This work aims to present a monitoring and active balancing system for a set of 24 cells using Analog Devices' DC2100B-C and DC2100B-D modules, which implement a flyback converter balancing technique. The DC2100B Demonstration Circuit is designed as a Bidirectional Cell Balancer, employing two LTC®3300-1 ICs to actively balance up to 12 Li-Ion cells. It incorporates a single LTC6804-2 Multi-Cell Addressable Battery Stack Monitor IC for cell voltage measurement and utilizes two LTC3300-1 ICs for active cell balancing. Additionally, the DC2100B-C variant includes a PIC18F47J53 microcontroller. To highlight the balancing process, cells were randomly discharged to create an imbalance among them. Experimental results show that active balancing is successfully achieved, with cell voltages reaching the same level after the process. Furthermore, the experimental results align with theoretical concepts, and to demonstrate the functionality of the balancing stand, some simulations of the system were conducted using MATLAB Simulink and PSIM. Considering the substantial number of cells in a battery pack and the associated high costs, the balancing process remains a focal point of interest. Active balancing serves to prevent premature cell damage and can improve the overall efficiency of the pack. In this work, the key research and engineering aspects involve designing an equalizer based on a flyback transformer for a battery pack and validating the applicability of the equalizer during both discharge and charge processes to enhance the maximum discharge capacity and available capacity.