Vanadium is a transition metal with a silvery-grey metallic appearance that is known for its high melting point, good structural strength, and ability to form alloys.
Up until a few years ago, vanadium was chiefly used as an alloying element in the production of steel and titanium alloys.
The chemical element was known to improve steel’s strength, toughness, and corrosion resistance and harden titanium to make it suitable for aerospace and other high-performance applications.
It has gained attention for its potential use in energy storage. Slowly but steadily, vanadium has become a crucial element in the production of large-scale, long-cycle life batteries known as vanadium redox flow batteries (VRFB).
Is vanadium a better alternative than lithium when it comes to batteries? What makes it so good for batteries?
Why is Vanadium Good for Batteries?
Even without pitting it against lithium, vanadium still come out as the superior option for battery manufacturers due to several reasons.
For example, the Earth’s crust contains more vanadium than it does lithium, and barring the high extraction costs of the former, commercialization of vanadium batteries would be happening at a more expedited rate.
VFRB batteries already outcompete all other solid batteries in utility-scale applications, like providing grid storage for renewable energy systems. It all boils down to vanadium’s properties, which are unexpectedly conducive for highly scalable energy storage:
It Has a High Energy Density
Energy density is the measure of the amount of energy that can be stored in a given volume or weight of a battery.
Higher energy density means that the battery easily stores more energy in a smaller and lighter package, which can be useful for applications where space and weight have to be limited.
VFRBs have the potential for high energy density due to vanadium’s ability to exist in multiple oxidation states. In a vanadium battery, the vanadium ions in the electrolyte can be charged or discharged by changing their oxidation state.
This is called a redox reaction. It allows VRFBs to store and release electrical energy by flowing the vanadium electrolyte through electrochemical cells and selectively oxidizing or reducing them at the electrodes.
Vanadium’s ability to exist in multiple oxidation states allows vanadium to provide a wide range of charge and discharge capacities for batteries. This means batteries made using vanadium can be designed to store a significant amount of charge per unit of mass or volume.
It Has a Long Cycle Life
Cycle life is the number of charge and discharge cycles a battery can undergo before its performance starts to degrade significantly.
Vanadium redox flow batteries can withstand over 20,000 charge and discharge cycles without a significant decrease in capacity. In comparison, lithium batteries begin to degrade after just 300 to 500 charge cycles.
This makes vanadium a far more suitable battery chemical for long-term energy storage applications.
It is Highly Scalable
In a vanadium battery, the electrochemical reactions occur in the electrolyte, an ionized solution stored in separate tanks made of either plastic or other non-conductive materials.
Increasing the capacity of a vanadium battery is typically a matter of changing the size of the electrolyte storage tanks. Larger tanks can store more vanadium electrolyte solution, while smaller tanks store less.
This vital attribute allows vanadium batteries to be readily scaled up or down to meet the energy storage needs of the application.
It is Very Safe
Vanadium batteries are generally considered safer than battery technologies like lithium. This is because the vanadium electrolyte used in VRFBs, for instance, is non-flammable and non-toxic, reducing the risk of fire and environmental contamination.
Additionally, separating the energy-storing vanadium ions from the electrodes in a VRFB improves the battery’s safety by preventing thermal runaway and capacity degradation, issues that can easily occur in other types of batteries.
Conclusion
Vanadium exhibits several attributes that make it a promising candidate for the future of battery technology.
Its high energy density, excellent cycling stability, and scalable design (in the form of vanadium redox flow batteries) make it an excellent choice for energy storage applications such as renewable energy integration and grid-level energy storage—applications that lithium batteries cannot easily scale to.
The chemical’s ability to exist in multiple oxidation states gives it a remarkably high charge/discharge efficiency and a long cycle life, both critical factors for the commercial viability of batteries.
The fact that it is also abundant in the Earth’s crust, very easy to source, and considered a relatively environmentally friendly option compared to some other materials used in batteries, suggests that vanadium batteries are here for the long haul.
