The strength and durability of steel and other alloys is greatly enhanced by adding a small amount of vanadium, currently the primary use of this critical mineral. While this toughness is legendary, the future of vanadium could rest in another set of more subtle traits that could make it the element of choice for large-scale storage of renewable energy generated by wind and solar.
“Vanadium is becoming more widely used in green technology applications, especially in battery technology,” the U.S. Geological Survey penned in a 2018 report on critical minerals and metals.
Due to its importance to both the economic and strategic security of the United States, coupled with the fact that none of this high-strength metal is mined domestically, the alloying properties of vanadium alone would likely be enough to elevate vanadium to critical status.
The USGS estimates that roughly 9,800 metric tons of vanadium was consumed in the United States during 2018, a 13 percent increase over 2017. Approximately 93 percent of this vanadium was used in steel and other alloys.
Vanadium’s potential as a battery metal, however, could be a market disruptor.
This emerging technology, coupled with an expected major increase in Chinese demand of vanadium for alloys, has resulted in soaring prices for this metal.
“Average 2018 vanadium pentoxide prices almost doubled compared with 2017 prices, and ferrovanadium prices more than doubled to $33 per pound in 2018 compared with 2017,” USGS penned in its annual Mineral Commodities Summaries 2019.
Rising prices, coupled with growing demand from traditional and emerging applications, has prompted mineral exploration companies to identify new sources of this alloy-battery metal.
One such explorer, Northern Cobalt Ltd., has nabbed a large vanadium-bearing magnetite prospect in Southeast Alaska.
Batteries could be the future
While alloys currently drive the market for vanadium, emerging battery technologies will likely add to the demand for this critical metal.
One such technology, is vanadium redox-flow batteries (VRBs). These batteries, which use vanadium in solution as both the anode and cathode, could be the answer for storing large amounts of electricity that could be fed into power-grids when the need arises.
“Because of their large-scale storage capacity, development of VRBs could prompt increases in the use of wind, solar, and other renewable, intermittent power sources,” USGS wrote.
Taking advantage of vanadium’s ability to exist in solution in four different oxidation states, the vanadium redox battery uses vanadium in two of these states as electroactive elements, instead of separate elements for the cathode and anode.
The amount of energy a VRB can store is really only limited by the size of the storage tank built to hold the vanadium solutions, which are separated by a proton-exchange membrane.
These batteries can also remain completely uncharged over an extended period without major effects, another advantage that makes them particularly well suited for backup electrical storage.
The disadvantages are that these VRBs store relatively small amount of energy for their size and weight, making them less useful for mobile applications such as electric vehicles.
This does not mean vanadium will not be used to power future cars.
“Lithium-vanadium-phosphate batteries produce high voltages and high energy-to-weight ratios, which make them ideal for use in electric cars,” USGS penned.
In these batteries, the lithium-vanadium phosphate serves as the cathode, and lithium metal serves as the anode.
While still early stage, this adds to the reason mining companies are looking for new supplies of vanadium.