by Ange A. Maurice, Pablo A. Prieto-Díaz and Marcos Vera
Abstract:
We present a novel, low-cost optical sensor for accurate real-time monitoring of the state of charge (SoC) and total vanadium concentration in vanadium flow batteries. Using only six discrete wavelengths, the sensor achieves precision comparable to full-spectrum methods while significantly reducing equipment costs and complexity. A general deconvolution method is used to measure the SoC and the total vanadium concentration in both the negolyte and posolyte, with calibration covering concentrations from 1.21 to 1.82 mol/L. We achieve root mean square error (RMSE) values of 1.2% and 3.2% for the SoC, and 54 mmol/L and 97 mmol/L for the total vanadium concentration in the negolyte and posolyte, respectively, demonstrating excellent agreement with reference ultraviolet visible (UV-vis) data. In addition, a wavelength optimization study is proposed to determine the optimal number and placement of spectral channels, providing a basis for the design of tailored optical sensors for vanadium electrolytes.
Reference:
Ange A. Maurice, Pablo A. Prieto-Díaz and Marcos Vera, “Low-cost optical multi-wavelength sensor for accurate real-time state-of-charge monitoring in vanadium flow batteries”, Advanced Sensor and Energy Materials, vol. 5, no. 1, pp. 100183.
Bibtex Entry:
@article{maurice_low-cost_2026,
title = {Low-cost optical multi-wavelength sensor for accurate real-time state-of-charge monitoring in vanadium flow batteries},
volume = {5},
issn = {2773-045X},
url = {https://www.sciencedirect.com/science/article/pii/S2773045X26000063},
doi = {10.1016/j.asems.2026.100183},
abstract = {We present a novel, low-cost optical sensor for accurate real-time monitoring of the state of charge (SoC) and total vanadium concentration in vanadium flow batteries. Using only six discrete wavelengths, the sensor achieves precision comparable to full-spectrum methods while significantly reducing equipment costs and complexity. A general deconvolution method is used to measure the SoC and the total vanadium concentration in both the negolyte and posolyte, with calibration covering concentrations from 1.21 to 1.82 mol/L. We achieve root mean square error (RMSE) values of 1.2% and 3.2% for the SoC, and 54 mmol/L and 97 mmol/L for the total vanadium concentration in the negolyte and posolyte, respectively, demonstrating excellent agreement with reference ultraviolet visible (UV-vis) data. In addition, a wavelength optimization study is proposed to determine the optimal number and placement of spectral channels, providing a basis for the design of tailored optical sensors for vanadium electrolytes.},
number = {1},
urldate = {2026-03-16},
journal = {Advanced Sensor and Energy Materials},
author = {Maurice, Ange A. and Prieto-Díaz, Pablo A. and Vera, Marcos},
month = mar,
year = {2026},
keywords = {Low-cost optical sensor, State of charge monitoring, UV-vis spectroscopy, Vanadium electrolyte concentration, Vanadium redox flow battery},
pages = {100183},
file = {ScienceDirect Full Text PDF:E:\Usuarios\Administrator\Zotero\storage\CKA47PLP\Maurice et al. - 2026 - Low-cost optical multi-wavelength sensor for accurate real-time state-of-charge monitoring in vanadi.pdf:application/pdf},
}