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为了解决大规模蓄能全钒液流电池中传质不均衡而导致电池寿命缩短的问题,本文建立了一个三维数值模型研究全钒液流电池中的传质规律.模型耦合了Nernst-Planck方程、Butler-Volmer方程、Nernst方程、质子交换膜中的传质方程等.模型模拟了全钒液流电池中不同价态钒离子的分布规律,以及电解质电流密度和电解质电势分布规律.研究发现:在放电过程中,沿电解液流动方向,反应物的离子浓度逐渐减少,生成物的离子浓度逐渐增加;电解质电流密度在膜表面达到最大,向两侧的集流体方向逐渐降低;沿电解液流动方向和阴极指向阳极方向,电解质电势逐渐降低.结果表明:集流体附近电化学反应更剧烈,质子在Nation膜中的传递主要是依靠电渗作用和浓差作用.“,”In order to solve the shortened battery life problem caused by imbalance mass transfer in all vanadium flow batteries,A three-dimensional mathematical model was established to simulate the mass transfer regularity in all vanadium flow batteries through coupling the proton exchange membrane mass transfer equation with Nernst-Planck equation,Butler-Volmer equation,and Nernst equation.The distribution of vanadium ions in different valence states,electrolyte current density and electrolyte potential of the vanadium redox flow battery was simulated.When discharging,reactant ions concentration decreased gradually and product ions changed reversely along the electrolyte flow direction.Electrolyte current density reached to its maximum on the membrane surface but decreased gradually along two sides of the current collector flow direction.The electrolyte potential decreased gradually along the electrolyte flow and the direction from the cathode to the anode.The electrochemical reaction was more intense around the current collector.The proton transfer in the Nation membrane mainly relied on electroosmosis effect and concentration effect.