A Vanadium redox flow battery test facility of industrial size (IS-VRFB) has been recently built at the Energy Storage and Conversion Laboratory of University of Padua in order to investigate the performance potential of scaling-up from small-scale single-cell bench experiments. The facility is built around a 40-cell 600-cm^­2 active-area stack and two 550-litre tanks. The facility is provided with advanced electronic bidirectional power supply, multiphysics instrumentation and data acquisition and control system. This paper reports on the commissioning of a multichannel Electrochemical Impedance Spectroscopy (EIS) system, tailored for such large stack, capable of operating in the range 0-30 kHz, with bias currents up to 400 A. Results from early experimental campaign will be also reported, which show the lack of uniformity among cells and how differences enlarge with increasing battery load conditions. Results can be instrumental in addressing the design of flow patterns inside a large stack.

References

• Alotto, M. Guarnieri and F. Moro, “Redox flow batteries for the storage of renewable energy: A review,” Renew Sus. Energ Rev. 29, (2014): 325–335.
• Guarnieri, A. Trovò, A. D’Anzi, P. Alotto, “Developing vanadium redox flow technology on a 9-kW 26-kWh industrial scale test facility: design review and early experiments”, Appl Energy, 230 (2018) 1425-1434. DOI: 10.1016/j.apenergy.2018.09.021.
• Trovò, G. Marini, A. Sutto, P. Alotto, M. Giomo, F. Moro, M. Guarnieri, “Standby thermal model of a vanadium redox flow battery stack with crossover and shunt-current effects”, Appl Energy, 240 (2019) 893-906.
• Trovò, A. Saccardo, M. Giomo, F. Moro, M. Guarnieri, “Thermal modeling of industrial-scale vanadium redox flow batteries in high-current operations”, J Power Sources, in print.