Processing and Pretreatment Effects on Vanadium Transport in Nafion Membranes. Issue 1 (13th October 2015)

• Record Type: Journal Article
• Authors: Xie, Wei; Darling, Robert M.; Perry, Mike L.
• Is Part Of: Journal of the Electrochemical Society. Volume 163:Issue 1(2016)
• Page Start: A5084
• Page End: A5089
• Publication Date: 2015-10-13
• Subjects: Ionic Conductivity -- Nafion® -- Perfluorosulfonic Acid Membrane -- Pretreatment -- Redox Flow Battery -- Vanadium Permeability; Electrochemistry -- Periodicals; 541.3705
• DOI: 10.1149/2.0111601jes
• Languages: English
• ISSNs: 0013-4651

Abstract

Abstract : This work describes how manufacturing processes and pretreatments affect the proton conductivity and vanadyl permeability of Nafion ® and how these properties are altered by running in a cell. Five Nafion membranes were examined: reinforced XL100, dispersion cast NR211 and NR212, and extruded N115 and N117. The membranes were subjected to pretreatments that included annealing at 120°C and immersing in ambient temperature and boiling water and sulfuric acid. Vanadyl permeability varied by ∼15X with pretreatment and ∼3X with manufacturing process. Variations in ionic conductivity were comparatively modest: ∼1.5X with pretreatment and ∼1.2X with processing. Differences in permeability can be eliminated by annealing the extruded membranes above their glass-transition temperature or by immersing in boiling sulfuric acid. The differences induced by processing and pretreatments were largely absent from membranes removed from vanadium redox cells subjected to repeated charge/discharge cycles.