A flow battery consists of tanks, a pump system and battery cells, also known as a battery stack. The tanks contain a liquid electrolyte solution that serves as a storage medium. The electrolyte is pumped through the battery cells to charge and discharge the battery, binding electrons.
[pdf] A critical factor in designing flow batteries is the selected chemistry. The two electrolytes can contain different chemicals, but today the most widely used setup has vanadium in different oxidation states.
[pdf] Grid scale BESS can be used for frequency regulation, peak shaving (i.e. reducing demand during peak hours to lower grid stress or avoid high tariffs) and grid stability. The 750 kW BESS project at the PECC2 Innovation Hub in Ho Chi Minh City is an example of this.
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