新型径向流动全钒液流电池单元数值模拟

Numerical simulation of a novel radial all-vanadium flow battery cell

全钒液流电池因其选址自由、效率高、寿命长以及安全性高等特点,广泛应用于大规模储能领域,然而现有电池结构单一,无法满足储能领域高速发展的需求。为提高全钒液流电池电化学性能,采用数值模拟方法,针对新型径向流动全钒液流电池单元,建立电池单元内部电化学反应与热质传递耦合作用数学物理模型,获得了不同电解液进口数量下新型电池单元内部多物理场耦合输运特性分布规律,包括电解液速度场、压降、离子浓度以及电极电势的分布规律。结果表明,电池电解液进口数量的增加,可以有效改善电解液在多孔电极内的输运性能,提升多孔电极内部离子浓度分布均匀性,削弱离子浓度极化现象,提高电极电势,增强电池性能。同时,在多孔电极入口处设置电解液分配管,可以有效减小电解液流动阻力,提升电解液分配均匀性,进一步提升电池性能。仿真模拟的研究结果可为全钒液流电池结构的优化设计提供参考。

All-vanadium redox flow batteries are widely used in the field of large-scale energy storage because of their freedom of location,high efficiency,long life,and high safety.The existing battery,on the other hand,has a single structure and cannot meet the needs of the rapidly developing energy storage field.A numerical simulation method is used to establish a mathematical and physical model for the coupling of electrochemical reactions and heat and mass transfer inside the battery cell to achieve the new radial flow all-vanadium flow battery cells.The distribution law of multi-physics coupling transport characteristics is obtained for different inlet quantities.Ion concentration field,electrolyte velocity field,voltage drop,and electric potential distribution law are all included.The results show that optimizing the number of electrolyte inlets can effectively improve electrolyte transport performance in porous electrodes,improve the uniformity of the ion concentration distribution in porous electrodes,weaken ion concentration polarization,increase the electrode potential,and enhance the battery performance.Simultaneously,the electrolyte distribution channel is set at the electrolyte flow inlet,thereby effectively reducing electrolyte flow resistance,improving electrolyte distribution uniformity,and improving battery performance.The simulation research results can be used to optimize the design of a flow battery.