Analysis of Battery Performance and Mass Transfer Behavior for Organic Redox Flow Battery with Different Flow Fields

Abstract

How mass transfer performance limits the development of organic flow batteries, which are regarded as the emerging electrochemical energy storage technology, is unclear. Mass transfer behavior in the electrode is influenced by the flow fields, which is indispensable. A three-dimensional and steady numerical model of the organic flow battery is established and the results are verified by experimental data. The battery performance and mass transfer behaviors are analyzed under different flow field for the charge/discharge processes based on this model. Compared with other flow fields, the interdigital flow field can achieve the best charge-discharge performance, mainly due to the improvement distribution uniformity of active species. The average concentration of the interdigital flow field is 45.1% higher than that of the conventional flow field. The effects of the flow rates and initial concentration of electrolyte on the battery performance are investigated, and the results indicate that appropriate inlet flow rate can lead to the highest net discharge powers and power-based efficiency of the flow battery. Although increasing the initial concentration can improve the battery performance, the improvement is too slight when the concentration is high enough, which can lead to waste of the active species.

Mass Transfer Characteristic Analysis and Optimization of Flow Field for Neutral Organic Redox Flow Battery Based on 1‐DPAQCl

“…The details of i neg and i pos , η neg and η pos , E eq,neg and E eq,pos can be found at reference [12].…”

“…According to the conservation of charge, the law of charge balance between solid and liquid phases is shown as (12): ChemistrySelect…”

“…It is well accepted that the mass transfer of flow batteries based on initial concentration, inlet velocity and flow field can influence the battery performance [11,12] . During the past decade, there are plenty of investigations on the flow field and electrode optimization [13,14] .…”

“…[9,10] It is well accepted that the mass transfer of flow batteries based on initial concentration, inlet velocity and flow field can influence the battery performance. [11,12] During the past decade, there are plenty of investigations on the flow field and electrode optimization. [13,14] Yang et al [15] established a 2D computational model of VRFB and found the way of variable flow rate can improve the overall properties of battery.…”