State of charge monitoring for vanadium redox flow batteries by the transmission spectra of V(IV)/V(V) electrolytes

A method is presented for monitoring the state of charge (SOC) of vanadium redox flow batteries (VRBs) by the transmission spectrum of the positive electrolyte [V(IV)/V(V)]. We use the transmission spectrum rather than the absorption spectrum for better signal noise ratio. In order to solve the complicated relations between the spectrum and the SOC of the VRB, the entire shape of the spectrum is utilized instead of the data at one wavelength. We experimentally demonstrate that SOCs from 0 to 100 % can be monitored by comparing the transmission spectra of the positive electrolytes [V(IV)/V(V)] with the database, which is previously built by detecting standard samples. The method has potential ability to monitor the level of imbalances of the VRB, which is important for rebalancing the electrolyte and restoring the capacity loss of a VRB.

[1]  Emin Caglan Kumbur,et al.  Open circuit voltage of vanadium redox flow batteries: Discrepancy between models and experiments , 2011 .

[2]  M. Mench,et al.  Redox flow batteries: a review , 2011 .

[3]  Maria Skyllas-Kazacos,et al.  Progress in Flow Battery Research and Development , 2011 .

[4]  Xinping Qiu,et al.  Self-assembled polyelectrolyte multilayer modified Nafion membrane with suppressed vanadium ion crossover for vanadium redox flow batteries , 2008 .

[5]  Hui Ma,et al.  Parallel scan spectral surface plasmon resonance imaging. , 2008, Applied optics.

[6]  Jun Liu,et al.  Electrochemical energy storage for green grid. , 2011, Chemical reviews.

[7]  Anthony G. Fane,et al.  New All‐Vanadium Redox Flow Cell , 1986 .

[8]  Hui Ma,et al.  Quasi-confocal, multichannel parallel scan hyperspectral fluorescence imaging method optimized for analysis of multicolor microarrays. , 2010, Analytical chemistry.

[9]  Xinping Qiu,et al.  Nafion/SiO2 hybrid membrane for vanadium redox flow battery , 2007 .

[10]  Xinping Qiu,et al.  Nafion/organically modified silicate hybrids membrane for vanadium redox flow battery , 2009 .

[11]  Xinping Qiu,et al.  Nafion/organic silica modified TiO2 composite membrane for vanadium redox flow battery via in situ sol–gel reactions , 2009 .

[12]  Xinping Qiu,et al.  Influences of permeation of vanadium ions through PVDF-g-PSSA membranes on performances of vanadium redox flow batteries. , 2005, The journal of physical chemistry. B.

[13]  Maria Skyllas-Kazacos,et al.  State of charge monitoring methods for vanadium redox flow battery control , 2011 .

[14]  Yonghong He,et al.  A two-dimensional polarization interferometry based parallel scan angular surface plasmon resonance biosensor. , 2011, The Review of scientific instruments.