As in lithium-ion batteries, the main components of a flow battery system are two electrodes and electrolyte as the ionic transport medium. In this case, however, the chemical reaction occurs in the liquid electrolyte and not at the electrodes. “In practical terms, the difference is that flow batteries are much heavier and bulkier than conventional batteries, which makes them unsuitable for portable devices. But they are better in terms of capacity, longevity and operational flexibility, i. e. the features valuable in grid-scale energy storage. In addition, vanadium storage systems can be recharged quickly, they are fire-proof and do not require any imported raw materials. And vanadium as such is easy to recycle,” says Mikhail Pugach, Senior Research Scientist at the Energy Center, as cited by Skoltech.
Unlike lithium-ion batteries, vanadium storage systems can maintain their capacity almost unchanged after a large number of charge-discharge cycles, provided that no errors are made in design and maintenance. Such errors can be prevented by using the mathematical model developed by the Skoltech research team. The model helps the manufacturer to select the optimal materials that will increase the battery’s reliability and slow down capacity degradation. The servicing company, in its turn, will be advised on fixing the electrolyte composition balance, which tends to be disrupted over time.
The model relies on a detailed description of physical processes occurring within the device. This ensures high predictive accuracy using just a small input dataset. “The physical model is derived from a model that my colleagues and I published earlier based on the results of my dissertation study at Skoltech. The previous model required detailed information on membrane properties, and the new one does need that because we introduced additional coefficients allowing for model adjustment to the current state of the membrane,” Pugach explains (Skoltech citation).
The research results can be applied to the operation of vanadium batteries, which are not only used for renewable energy balancing, but also as a backup power source for data centers.
