Vanadium redox flow batteries (VRFBs) can effectively solve the intermittent renewable energy issues and gradually become the most attractive candidate for large-scale stationary energy storage. However, their low energy density and high cost still bring challenges to the widespread use of VRFBs.
This demonstrates the advantage that the flow batteries employing vanadium chemistry have a very long cycle life. Furthermore, electrochemical impedance spectroscopy analysis was conducted on two of the battery stacks. Some degradation was observed in one of the stacks reflected by the increased charge transfer resistance.
The energy is stored in the vanadium electrolyte kept in the two separate external reservoirs. The system capacity (kWh) is determined by the volume of electrolyte in the storage tanks and the vanadium concentration in solution. During operation, electrolytes are pumped from the tanks to the cell stacks then back to the tanks.
It is worth noting that no leakages have been observed since commissioned. The system shows stable performance and very little capacity loss over the past 12 years, which proves the stability of the vanadium electrolyte and that the vanadium flow battery can have a very long cycle life.
Here’s how it works: All of these tanks are lined up in pairs. One tank holds vanadium with a more positive charge, while the other tank holds vanadium with a more negative charge. You can think of them like the + and - sides of the batteries sitting in a TV remote or a flashlight.
One tank holds vanadium with a more positive charge, while the other tank holds vanadium with a more negative charge. You can think of them like the + and - sides of the batteries sitting in a TV remote or a flashlight. Every tank is hooked up to a set of pipes that pump vanadium into battery cells stacked in cabinets on the second floor.