Is vanadium ion permeability independent of membrane thickness?

Schilling M, Christanto V, Ikhsan MM, Zeis R, Henkensmeier D (2025)

Publication Type: Journal article

Publication year: 2025

Journal

Journal of Membrane Science Elsevier

Book Volume: 734

Article Number: 124505

DOI: 10.1016/j.memsci.2025.124505

Abstract

Testing the diffusion-driven crossover of vanadium ions in diffusion cells is a standard characterization method for membranes used in vanadium redox flow batteries. For better comparability, the flux is recalculated into a permeability value by normalizing the flux for membrane thickness, area, the cell volume, and the concentration difference between the donating and receiving cells. The assumption is that permeability is an intrinsic material property, independent of membrane thickness. However, this work reveals that this assumption is not correct. By analyzing the vanadium crossover through membranes of different thickness, it is demonstrated that the transport of VO2+ ions across membranes is controlled by two transport resistances: RIF (a resistance hindering ion transport over the membrane/solution interface into and out of the membrane) and Rbulk (the transport resistance through the membrane). Comparable permeability values are only obtained when membrane thicknesses are so large that Rbulk ≫ RIF. Consequently, the permeability data reported in the literature might have low accuracy. RIF emerges as an important new development target, which, if well understood, can lead to breakthroughs in membrane performance.

Authors with CRIS profile

Roswitha Zeis

Involved external institutions

Helmholtz Institut Ulm DE Germany (DE) Korea Institute of Science and Technology (KIST) / 한국과학기술연구원 KR Korea, Republic of (KR)

How to cite

APA:

Schilling, M., Christanto, V., Ikhsan, M.M., Zeis, R., & Henkensmeier, D. (2025). Is vanadium ion permeability independent of membrane thickness? Journal of Membrane Science, 734. https://doi.org/10.1016/j.memsci.2025.124505

MLA:

Schilling, Monja, et al. "Is vanadium ion permeability independent of membrane thickness?" Journal of Membrane Science 734 (2025).

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