Authors: Ms. Nirmala R G, Pratap K V, Nithilan I
Abstract: The growing adoption of electric vehicles (EVs), renewable-energy microgrids, and portable power systems has intensified the need for efficient and reliable battery management strategies. Conventional passive balancing circuits in lithium-ion battery packs dissipate excess energy as heat, resulting in low efficiency, poor scalability, and thermal stress. This paper presents an Active Cell Balancing Battery Management System (ACB-BMS) employing a bidirectional buck–boost converter topology integrated with an Extended Kalman Filter (EKF)-based state-of-charge (SOC) estimation algorithm. The system dynamically redistributes charge between cells, achieving faster equalization and significantly reduced energy loss compared with resistor-based methods. The EKF enables accurate real-time tracking of each cell’s SOC, improving safety and charge control under varying load and temperature conditions. A complete MATLAB/Simulink simulation model of the proposed system has been developed and validated, demonstrating superior voltage uniformity, faster balancing response, and enhanced energy efficiency. The proposed approach forms a practical foundation for next- generation intelligent BMS architectures suitable for electric vehicles and hybrid renewable-energy storage. Future hardware implementation is planned to extend the technology toward commercial-grade embedded platforms.
