In this work, the graphite felt electrode for an iron-vanadium redox flow battery (RFB) with deep eutectic solvent (DES) electrolyte is modified by the method of electrolysis in ammonium sulfate, and a segmented electrode is prepared by combining the pristine graphite felt part and the modified part. The electrolysis process not only makes the outermost layer of graphite felt partially fall off which enlarges the specific surface area, but also increases the number of oxygen-containing functional groups on the surface of the graphite felt. To uniform the electrochemical reaction along the electrolyte flow direction and reduce the over-potential, the pristine graphite felt part of the segmented electrode is placed in the electrolyte inlet region, and the modified graphite felt part is put in the outlet region. With the segmented electrode, the single cell test shows the maximum power density is 10.63% higher than that of the pristine electrode under the same operating condition, and the energy efficiency is also higher for charge-discharge cycles. Therefore, the accessibly prepared segmented electrode is promising for improving the performance of the DES electrolyte redox flow battery.

在这项工作中，通过在硫酸铵中电解的方法对具有深共熔溶剂（DES）电解质的铁钒氧化还原液流电池（RFB）的石墨毡电极进行了修饰，并通过组合原始石墨毡制备了分段电极部分和修改的部分。电解过程不仅使石墨毡的最外层部分脱落，这增大了比表面积，而且增加了石墨毡表面上含氧官能团的数量。为了使沿着电解质流动方向的电化学反应均匀并且减小过电势，将分段电极的原始石墨毡部分放置在电解质入口区域中，并且将改性石墨毡部分放置在出口区域中。使用分段电极，单电池测试表明，在相同工作条件下，最大功率密度比原始电极高10.63％，并且在充放电循环中能量效率也更高。因此，容易获得的分段电极有望改善DES电解质氧化还原液流电池的性能。