An Improved Modular Charge Equalization Structure for Series Cascaded Battery

To extend battery lifetime and maximize battery utilization capabilities in series cascaded battery stacks, Charge Equalization (CE) is essential. To achieve this goal, efficiency, minimum added costs and elements, CE time, operating frequency, maximum number of possible serial connections, element ratings, and control simplicity, are the most important concerns. In this paper, an improved modular active CE structure for all possible operation modes is presented. The topology has the benefit of minimum added elements, simple and effective control algorithm, suitable efficiency as well as modularity. Presented simulation results, as well as comprehensive analysis of the circuit, verify the authenticity of the proposed structure. The obtained results show that the batteries are balanced with suitable speed and efficiency.