Solar Power Assisted Passive and Active Cell Balancing System: A Comprehensive Analysis

Lithium-ion battery system is generally used in industries where energy is always on demand. Battery cell balancing is an important feature for the long-term survival of the batteries because unbalancing of battery cell may cause deterioration of the battery life cycle and efficiency. This paper proposes a solar power assisted passive and active cell balancing system for rechargeable batteries. Three techniques are implemented in the paper to achieve cell balancing of the battery pack i-e. Passive cell balancing, active cell balancing using multiple switched capacitors, and active cell balancing using single switched capacitor. Two operational modes are also discussed in the paper i-e. solar balancing mode and storage balancing mode. The storage balancing mode is triggered automatically when the solar power becomes unavailable. The simulation model of the system is designed in Simulink and hardware model is implemented based on the simulation results. The comparative analysis of the obtained results signify that the equalization of battery cell voltages is achieved more prominently by active cell balancing on the basis of state of charge (SoC) of Li-ion cells rather than passive approach.