What Are Vanadium Flow Batteries?
Vanadium flow batteries are one of the technologies that is enabling the transition to renewable energy. While vanadium batteries are not a new technology, our team at StorEn has built upon the strengths of existing vanadium flow batteries to create a product that better meets the requirements of residential and industrial energy storage.
Vanadium Flow Battery Technology
Also known as vanadium batteries and vanadium redox flow batteries, the current vanadium flow battery design was patented by the University of New South Wales in 1986, but this technology was pioneered by P.A. Pissoort in the 1930s and NASA researchers A. Pelligri and P.M. Spaziante in the 1970s.
Dr. Maria Skllas-Kazacos of Australia designed the first known commercial all-vanadium flow battery, which is a rechargeable flow battery technology that stores energy by using vanadium’s ability to exist in solution in four different oxidation states. This allows vanadium flow batteries to store energy with only one electroactive element rather than two, eliminating metal cross-contamination.
Vanadium redox flow batteries have four main parts:
At the core of a vanadium redox flow battery is the battery stack, where the ion exchange occurs during charging and discharging. Electrolyte flows are separated with an ion-permeable membrane, allowing the ions to cross freely in order to complete the electric circuit. Electricity is converted into chemical energy by a redox reaction.
Positively Charged Electrolyte Tank
The positive electrolyte circuit contains vanadium ions with an oxidation state of +4 in an uncharged state. When energy needs to be stored, the electrolyte oxidizes, moving to an oxidation state of +5. The electrolyte is completely shifted to vanadium +5 when the battery is fully charged.
Negatively Charged Electrolyte Tank
The negative electrolyte circuit contains vanadium ions with an oxidation level of +3 in an uncharged state. The electrolyte reduces charging to a +2 oxidation state when storing energy. The electrolyte is completely shifted to vanadium +2 when the battery is fully charged.
Both positive and negative electrolyte circuits have individual pumping systems. The circuits feed electrolyte to the relevant half battery cells.
Advantages of Vanadium Flow Batteries
Vanadium redox flow batteries are often compared to lithium batteries, which are also used for energy storage. No matter your criteria, vanadium flow batteries nearly always come out ahead, with the exception of size. Hence vanadium flow batteries are preferable to lithium in all stationary applications. StorEn vanadium batteries:
Discharge at 100% capacity throughout their entire lifetime.
Can last over 25 years without any degradation of capacity.
Are a sustainable energy storage solution.
Have a Battery Management System that indicates when maintenance is needed.
Are more cost-effective than lithium batteries.
Are safer, as they are non-flammable and non-explosive.
Offer more flexibility in use, including at low temperatures.
These advantages make StorEn vanadium flow batteries a viable option for helping more homeowners and businesses achieve independence from the electrical grid and reduce their energy costs.