本文综合考虑氧化还原二次电池内部的电化学反应和电池组漏电电流，建立了氧化还原电池组的等效电路模型. 以1 kW额定输出功率的全钒液流储能电池组为例，测试电池组暂态响应和自放电曲线，确定了等效电路模型的重要参数，比较模拟结果与实验结果，计算电池组的内阻和自放电电流，可知漏电电流造成的容量损失约占系统总容量损失的60%左右.
This paper introduces an equivalent circuit model for a redox flow battery stack. The model combines the electrochemical reaction of the battery cell and the shunt current of the battery stack. An all-vanadium redox flow battery stack of 1kW rated output power is tested through transient response and self-discharge experiments. All the parameters used for the modeling are obtained. Calculated shunt current and distribution of calculated battery voltage are shown in the results. It is concluded that the impedance of the battery stack can be obtained by the experimental results of the transient response and self-discharge measurements. The capacity lose of about 60% for the battery system is caused by the shunt current.
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