Open AccessCurrent-Driven Vanadium Crossover as a Function of SOC and SOD in the Vanadium Redox Flow Battery
Author(s) -
Jonathan T. Vardner,
Angela A. Ye,
David A. Valdes,
Alan C. West
Publication year - 2020
Publication title -
journal of the electrochemical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.258
H-Index - 271
eISSN - 1945-7111
pISSN - 0013-4651
DOI - 10.1149/1945-7111/ab88bc
Subject(s) - vanadium , flow battery , electrolyte , state of charge , chemistry , redox , separator (oil production) , oxidation state , analytical chemistry (journal) , battery (electricity) , inorganic chemistry , materials science , thermodynamics , electrode , chromatography , metal , power (physics) , physics , organic chemistry
The performance of vanadium redox flow batteries (VRFBs) is impacted by the diffusion and migration of the vanadium species across the separator. In this work, the vanadium crossover as a function of current density for vanadium-containing electrolytes of various state of charge (SOC) and state of discharge (SOD) is measured. Experiments conducted with electrolytes at complete charge/discharge yielded direct measurements of the transference numbers of the vanadium species. The transference numbers of V 2+ , V 3+ , VO 2+ , and VO 2 + were estimated to be 0.064 ± 0.002, 0.087 ± 0.003, 0.068 ± 0.003, and 0.018 ± 0.002, respectively. Experiments conducted with electrolytes at intermediate states of charge/discharge yielded direct measurements of the sum of transport numbers of the vanadium species. The transport number estimates are quantitatively related to faradaic efficiency loss and capacity fade of a working VRFB.