Enhanced Modular Battery Management System Based on Active Balancing Technique for Electrified Systems

The growing deployment of electrified transportation and renewable energy systems has increased the demand for scalable, cost-effective, and reliable battery management solutions, particularly for systems utilizing recyclable lithium-ion cells. The recyclable battery cells often suffer from voltage inconsistency, capacity mismatch, and nonuniform aging, which significantly degrade battery performance and reliability. This paper presents a modular battery management system (BMS) incorporating an active balancing technique specifically designed to address the challenges of using recyclable battery cells. The proposed architecture follows a hierarchical structure consisting of a main control module and multiple branch modules, enabling flexible scalability for various electrified applications. Comprehensive simulation and experimental investigations are conducted to evaluate suitable battery package configurations that are based on recyclable battery cells. with a comparative analysis between series–parallel and parallel–series arrangements. Additionally, active and passive balancing strategies are assessed using detailed modeling and state-of-charge (SoC) estimation techniques. The simulation and experimental results demonstrate that the series–parallel configuration exhibits superior stability and robustness when operating with degraded cells. Moreover, the proposed active balancing approach significantly improves voltage alignment, reduces energy losses, and enhances SoC uniformity compared to passive balancing. Experimental results confirm that the novel modular BMS maintains battery cell voltage deviation within 50 mV and extends the usable battery capacity by approximately 10%. These findings highlight the effectiveness of the proposed system as a practical, low-cost solution for managing recyclable lithium-ion batteries in electrified and sustainable energy applications.