A Reconfigurable Battery Supercapacitor Hybrid Energy System with Active Balancing for Vehicle Applications

The concept of reconfigurable energy systems has become more and more popular in recent years for electric vehicle applications, which can largely enhance battery performance and extend battery lifetime. Active balancing is an advanced function realized by battery management systems (BMSs) to improve energy efficiencies and avoid potential over-charging risks. This paper proposed a reconfigurable hybrid energy system (HESS) that consists of one supercapacitor module, n lithium-ion modules, one DC/DC converter, and 3n switches, to enhance energy system performance with fast active balancing. The developed algorithms are to find out all possible configurations for a given lithium-ion module number and module section number, and the best configuration is selected based on the fastest balancing speed requirement. The proposed topology and algorithms are finally verified by simulations under standard vehicle driving cycles.