Novel cell balancing applied near-field coupling and Serial–Parallel Circuit configuration

Abstract

This paper proposes a near-field cell balancing method to be applied to batteries of higher capacity and power. This method involves a wireless power transfer to balance battery cells, which produces higher efficiency than conventional passive approaches, and faster equalization than active approaches. Cell balancing is a crucial function of the battery management system (BMS) that maintains the balance of charge and discharge between cells of individual batteries. Furthermore, this method is designed to meet the increasing demand for faster cell balancing associated with high-capacity and high-power batteries. We selected a serial–parallel configuration to minimize the technical concern for isolation, or energy transfer to unselected cells. Experiments were conducted with two battery cells, and voltage equalization accelerated by 51% when the proposed cell balancing approach was applied.