Balancing Control Strategy for Li-Ion Batteries String Based on Dynamic Balanced Point

Abstract

Li-ion battery is becoming the optimal choice for EV's power supply. In order to keep the Li-ion battery away from charging damage and prolong the battery's life, we present and evaluate here a special control strategy based on dynamic balanced point along with a non-dissipative equalizer. The main focus of the proposed control strategy is to insure that individual cell of a battery pack will be rapidly, efficiently and simultaneously balanced by adjusting equalizing current dynamically. In this paper, a model of four series connected Li-ion batteries pack has been established to evaluate proposed control strategy. The superior performance is shown by the simulation. Keywords-EV; Li-ion battery; dynamic balanced point; control strategy; non-dissipative equalizer; series connected batteries I.978-1-4799-0720-5/13/$31.00 ©2013 IEEE