全钒液流电池动态建模

Dynamic modeling of all-vanadium flow battery

建立了一个全面描述钒电池的电化学反应、泵损和电解液温度变化的零维动态模型,此模型包括三个子模型:电化学模型、机械模型和热力学模型。电化学模型综合考虑了浓差、活化、欧姆和离子等极化损失以及钒离子的交叉渗透。仿真结果表明,随SOC变化的电堆电压仿真值与实验值之间的平均绝对百分误差为6.84%,验证了模型的准确性。通过仿真结果研究了电流、电解液流量和温度等操作条件对电池充放电特性的影响。

In order to aid optimizing operate condition and designing control strategy, a dynamic model for the electrochemical reaction, pump loss and temperature change of the vanadium battery（VRB） was established. The model consisted of three sub-models： electrochemical model, hydraulic model and thermal model. The electrochemical model takes into account the concentration, activation, ohmic and ionic polarization losses and the vanadium ion crossover. The hydraulic model describes the hydraulic circuit of the electrolyte and determines the pumps loss. The reversible entropic heat and pumps loss are included in the thermal model. The simulation results show that the mean absolute percentage error between the simulation value and the experimental value of the stack voltage varied with the state of charge （SOCs） is 6.84%, so the accuracy of the model is verified. The model is applied to study the effects of current, electrolyte flow rate and temperature on the charge and discharge characteristics.