A multicell-to-multicell battery equalizer with more balancing modes based on half-bridge bipolar-resonant LC converter

Abstract

This paper proposes a multicell-to-multicell (MC2MC) equalizer based on the half-bridge bipolar-resonant LC converter (HBBRLCC), which collects energy from the consecutive more-charged cells (high-voltage group) through the positive and negative polarity selection switch matrix and the half-bridge switch matrix, and then releases the energy to the consecutive less-charged cells (low-voltage group). The paper includes configuration of the proposed equalizer, the mathematical model and simulation comparison with conventional equalizers, highlighting the superior high-speed balancing performance and excellent balancing efficiency of the proposed equalizer. An experimental prototype is built with four cells to verify the performance, and the balancing efficiencies in different balancing modes range from 81.45% to 87.62% with an average balancing power of 1.454W to 5.011W.