This research proposes a charge equalization scheme based on a flyback converter with the polarity-inverting folding switches together with a set of selection switches for series-connected batteries. By the selection switches, the converter can provide an additional charging current to the battery with the lowest loaded voltage. In addition to intervening a low current charging to prolong the discrepant charging, a finalizing individual charging is performed to ensure charge equalization even under extremely unbalanced situation. Thus, all the batteries can be allocated with appropriate electric charge through the proposed charge-balance strategy to make the voltage of all batteries be even after the charging process. Three sets of experiments with different initial conditions are performed. Experimental results show that the charge imbalance can be effectively reduced after the regular current charging for most practical cases. All batteries can be charged to their full capacities with individual charging, even under extremely unbalanced situation. Eventually, the voltage difference among batteries can be alleviated to about 50 mV.

中文翻译：

---

一种带充电电流分配的电池串充电均衡方案

本研究提出了一种基于反激式转换器的电荷均衡方案，该转换器具有极性反转折叠开关以及一组用于串联电池的选择开关。通过选择开关，转换器可以为负载电压最低的电池提供额外的充电电流。除了介入小电流充电以延长差异充电时间外，即使在极不平衡的情况下，也会执行最终的单独充电以确保充电均衡。因此，可以通过所提出的电荷平衡策略为所有电池分配适当的电荷，使所有电池的电压在充电过程后均匀。进行了三组具有不同初始条件的实验。实验结果表明，在大多数实际情况下，常规电流充电后可以有效减少电荷不平衡。即使在极度不平衡的情况下，也可以通过单独充电将所有电池充满电。最终，电池之间的电压差异可以减轻到大约 50 mV。