화학공학소재연구정보센터
Journal of the Electrochemical Society, Vol.160, No.4, A697-A702, 2013
Concentration Dependence of VO2+ Crossover of Nafion for Vanadium Redox Flow Batteries
The VO2+ crossover,. or permeability, through Nafion in a vanadium redox flow battery (VRFB) was monitored as a function of sulfuric acid concentration and VO2+ concentration. A vanadium rich solution was flowed on one side of the membrane through a flow field while symmetrically on the other side a blank or vanadium deficit solution was flowed. The blank solution was flowed through an electron paramagnetic resonance (EPR) cavity and the VO2+ concentration was determined from the intensity of the EPR signal. Concentration values were fit using a solution of Fick's law that allows for the effect of concentration change on the vanadium rich side. The fits resulted in permeability values of VO2+ ions across the membrane. Viscosity measurements of many VO2+ and H2SO4 solutions were made at 30-60 degrees C. These viscosity values were then used to determine the effect of the viscosity of the flowing solution on the permeability of the ion. (C) 2013 The Electrochemical Society. [DOI: 10.1149/2.004306jes] All rights reserved.