Dynamic charge equalisation for series-connected batteries

Abstract

A charge equalisation circuit is proposed for the series-connected battery bank in a serial charging scheme. The charge equalisation is based on buck–boost conversion, and hence is essentially nondissipative. The subcircuit associated with each battery acts as a current diverter to transfer the excess charging current from the fully charged batteries to the flat ones. By dynamic redistribution of charging energy, charge equalisation can be achieved more quickly and efficiently. The applicability of this approach is confirmed by experiments.