摘要
Abstract
Vanadium redox flow batteries are vital energy storage technologies for grid peak shaving.However,their energy efficiency and rate capability at high current densities remain limited.Herein,we developed an efficient electrochemical activation strategy in which pristine carbon felt(P-CF)was treated at 10 V in a 0.1 mol/L NH4H2PO4 solution to produce electrochemically activated carbon felt(E-CF).Comparative analyses of surface morphology,elemental composition,and wettability between P-CF and E-CF were performed using scanning electron microscopy,contact angle measurements,Raman spectroscopy,and X-ray photoelectron spectroscopy.The results reveal that(1)E-CF preserves its integral fiber framework while developing etched regions,and(2)abundant oxygen-containing functional groups are introduced,increasing the O/C atomic ratio from 5.14%to 28.94%and transforming the surface to superhydrophilic,as shown by the contact angle decreasing from 134.1° to 0°.Electrochemical tests demonstrate that ① E-CF exhibits a significantly reduced charge transfer resistance,enhancing vanadium ion reaction kinetics;② single cells assembled with E-CF achieve a voltage efficiency of 73.54%and an energy efficiency of 70.56%at 200 mA/cm2;and ③ after reducing the current density from 200 to 80 mA/cm2,capacity retention exceeds 80%.Compared with conventional treatments,this method offers advantages such as short processing time,operational simplicity,environmental friendliness,and cost-effectiveness.关键词
电化学活化/全钒液流电池/碳毡/含氧官能团Key words
electrochemical activation/all-vanadium redox flow battery/carbon felt/oxygen-containing functional groups分类
信息技术与安全科学
