You’ve read a lot about Lithium as the primary element in modern batteries powering just about everything electric. Get ready to hear more about Vanadium which is an element fundamental to a battery class intended for the long-term storage of large amounts of power. American Vanadium has recently introduced the CellCube vanadium flow battery to America.
First conceived of by NASA decades ago, the vanadium redox flow battery is a unique energy storage system where both the positive and negative electrodes are made of one metal – vanadium. This unique characteristic allows this type of energy storage system to avoid the classical electrochemical reaction of most batteries where the exchange of ions between electrodes of different elements result in a degradation of the battery with each charge and discharge cycle.
This gives the vanadium flow battery a number of advantages including a 20 year lifespan with minimal loss of efficiency and the ability to maintain 99% of the energy in cold storage for a year. As well, these batteries can repeatedly discharge all the way down to zero and back to 100% without damage.
Other batteries also cannot separate power from the energy stored and so come with shortcomings when asked to handle large amounts of power. To double the required power period of the vanadium battery, just double the amount of electrolyte. All this adds up to this class of batteries being best at storing power for two to eight hours, for 500 kW and on up. And while it has this unique long term storage capability, it can also perform short duration functions which increase the quality of the power that runs through the battery.
A new source
Most of the world’s vanadium now comes from China and to lesser extents, Russia, South Africa, and Venezuela, all unstable sources. But the big news is that soon the U.S. will be a primary supplier thanks to deposits found in Nevada.
The Gibellini project is expected to commence commercial production in 2016. “At present, the project is rapidly moving though the environmental permitting stage,” says American Vanadium CEO Bill Radvak. “We will be able to produce enough for about 850 MWh per year of batteries with the current recoverable vanadium electrolyte. The U.S. will be the global source of the material for the CellCube.”
The vanadium market has been expanding ahead of GDP with an extremely volatile price. “The new mine will be the only one in the U.S. and no others are on the horizon,” says Radvak. Vanadium pentoxide sells for about $5.37/lb (metalprices.com). The ore will be mined and refined into an oxide form as opposed to ferrovanadium, which goes into the classical market of strengthening steel. Two pounds of ferrovanadium in a ton of steel, for instance, makes it twice as strong, but it cannot be made into vanadium electrolyte.
Wind industry needs
The intermittency of wind requires an energy storage system capable of managing a huge amount of electrical power. The battery will allow managing power by peak shaving; that is charging during low demand periods and discharging power back into the grid during periods of high demand – or storing it when there is an excess amount of power on a windy day. Wind power also has a tremendous issue with the quality of power being produced requiring a battery capable increasing its quality by “smoothing” the power. The wind industry also needs a battery that will not wear out or degrade with use, a critical feature for renewable energy. Telecommunication companies would use the batteries as UPSs.
“It’s a new technology that builds new revenue streams and new business models,” says VP Operations, Mike Doyle. “For wind operators, we can make energy storage economical anywhere. Grid operators will have to give energy-storage owners fair value for the power they provide.”
New and pending storage regulations from FERC will also positively influence the storage market. “Such a battery lets anyone in energy generation think more like a mini utility, thanks to the deregulation of energy transmission and generation. These recent developments may rewrite how electricity has been generated and delivered for the last 100 years.”
The timing of these developments also seems good. Lithium-based batteries are showing promise and limitations. For instance, above 200 kW, Lithium’s duration capacity drops to 1 to 1.5 hr. The material still causes concern. Manhattan, for instance, does not allow Lithium batteries installations because of the fire hazard. The CellCube does not carry that restriction.
A better battery for electric vehicles may also be in the cards. Vanadium seems to stabilize and improve the performance of lithium batteries, although Radvak says that development is still a lab experiment at this time.
Doyle points out that central-power generation and transmission is a 100 year old idea and now power and control is becoming decentralized. Ultimately utilities might become marketplaces for power trading. For instance, a wind generator wants to sell at the best prices, and if that person can cut out utilities, that will be the future.
More about the vanadium flow battery
The design of the Vanadium redox flow battery is well suited for storing a wind farm’s output when it might be otherwise curtailed, and then putting onto the grid a few hours later, as might be needed for peak shaving. The battery at present is manufactured in Germany by Gildemeister Energy Solutions, (en.cellcube.com), now using material from sources such as South Africa and China. The company is expected to gear up production towards 2 GWh/yr after the Nevada mine comes on stream. The vanadium is stored in two tanks with power electronics on top. With no cross contamination of electrodes, the battery does not wear out. With about 40 to 50% of the cost of the battery being vanadium, a sure supply is key.
“The battery is well suited to going from zero to full charge in a short period and back many times without loss of capacity, which describes how it would function as a temporary power source supplementing the production from a wind or solar plant,” says VP of Operations Mike Doyle. “What’s more, the battery unit can be stacked together for storing large amounts of power in 200 kW power blocks combined with two hour duration electolyte blocks.”
The CellCube is intended as a turnkey building block for larger storage systems.
When an application calls for a 1 MWh battery, Doyle says the company would simply assemble a number of 40 foot containers of CellCubes that can be placed in any outdoor environment.
Filed Under: Energy storage, News