Oboroceanu, D,Quill, N,Lenihan, C,Eidhin, DN,Albu, S,Lynch, RP,Buckley, DN,Doeff, M,Manivannan, M,Jow, R,Kalra V,Liu, G

Arrhenius Variation of Precipitation Time for V-V in Vanadium Flow Batteries

BATTERIES AND ENERGY TECHNOLOGY JOINT GENERAL SESSION

2017

January

Published

1

()

ELECTRODE-KINETICS CELL ELECTROLYTE CARBON

49

63

Both visual observation and light-scattering measurements were used to investigate the stability of typical vanadium flow battery (VFB) catholytes. V2O5 precipitates after an induction time that decreases with increasing temperature and concentration of V-V and increases with concentration of sulphate. This was observed at 3060 degrees degrees C for V-V and sulphate concentrations of 1.4-2.11 and 3.7-5.3 mol dm(-3), respectively. Arrhenius plots of induction time show excellent linearity and the logarithm of induction time varies linearly with both sulphate and V-V concentration. An Arrhenius plot of induction times normalized to standard reference concentrations of sulphate and V-V for all solutions gave a good straight line. The activation energy estimated from the slope is E-# = 1.79 eV. Combining the Arrhenius Equation and the observed variation with sulphate and V-V concentrations, an equation was derived which enables us to simulate the induction time for any catholyte solution at any temperature in the range investigated.

10.1149/07518.0049ecst