How the massive ‘flow battery’ coming to an Army facility in Colorado will work
Fort Carson is getting a large new battery. It is located south of Colorado Springs. The groundbreaking ceremony for the new energy storage system is scheduled for this fall. Lockheed Martin, the contractor behind it, estimates that it could take eight to nine months to construct.
The battery will be able to produce a megawatt of electricity for as long as 10 hours, meaning that it is a 10-megawatt-hour device. This battery is different than the one in your cell phone, laptop or electric car. It is not a lithium-ion batteries. It is a redox flow lithium-ion battery.
In an press conference , Lockheed Martin describes the Fort Carson project as “the first megawatt scale, long-duration energy store system for the U.S. Department of Defense” and the energy storage devices known as flow batteries.
Why is the DOD interested energy storage?
“[The] DOD is concerned with ensuring that critical missions, operated from fixed installations, are able to continue operating if the grid goes down for long periods,” Roger Jenkins, the business development director for GridStar Flow at Lockheed Martin Missiles and Fire Control, said during a media briefing earlier this week. This could be due to “a storm event, such as we saw in Texas” or a hacking event by unfriendly actors .
In this case, Fort Carson actually has some battery storage already, thanks to a lithium-ion battery system. It also has a solar panel array on an old landfill that can produce 2 megawatts of juice. Jenkins stated that they are working on a larger solar array, which will be online in the same time as this battery. This existing tech will be supplemented by the new flow battery system.
So what’s a flow battery?
First, it is important to consider the lithium-ion battery that lives inside a device such as a smartphone or electric car. These batteries are small and can supply power to devices that have limited space.
Lithiumion batteries are made up of a few basic parts. They contain an anode and cathode as well as a liquid electrolyte. The electrolyte allows lithium ions to travel back and forth. The anode of the battery houses electrons. This is where the lithium ions are found. The electrons flow through the circuit when the battery powers something. The lithium ions move to the opposite side, which is called the cathode. (Here’s an animation, with the cathode pictured on the left.) As the name suggests, a separator in the electrolyte keeps the two sides apart, but the lithium ions can still pass through it. Many lithium-ion battery are made up of small cells, which can take the form of cylinders and pouches.
A flow battery is a large one. It actually consists of large tanks filled with liquid electrolytes. “Unlike many batteries, a redox flow battery is built with flowing electrolytes,” says Levi Thompson, the dean of the College of Engineering at the University of Delaware, as well as a professor of chemical engineering. “Most batteries have fixed [electrolytes].” The liquid electrolyte in a lithium-ion cell isn’t moving anywhere. It’s a medium for lithium ions to flow back-and-forth.
A flow battery is able to store a lot of energy because it’s moving and the tanks are large. “There’s no land constraint or limitation for many of these installations–it’s unlike a car battery where you have limited real estate.
This is why a large Army facility in Colorado can be a good location for a flow battery.
With a Lockheed Martin flow battery, the power is generated in large boxes, or power modules, that each contain four power stacks. The liquid electrolytes, which are stored in tanks, flow through many electrochemical cells in those stacks. They pass through membranes that keep them separated but allow ions through.
What are the benefits of a flow battery?
With its large tanks and flowing electrolytes, and the need for large open spaces, a flow batteries is not going to power an electric vehicle or laptop anytime soon. However, they do have their advantages. Thompson says that cost is the most important thing.
Another perk is that it theoretically lasts longer than the competition. Thompson says that it will cycle more than a lithium-ion batteries. He also points out that it can be recharged if it begins to degrade.
Thompson believes that these batteries could be a good choice for people who want to store energy from the grid. This could include energy made by solar panels which only produce juice when there is sunlight. He says that there is a real opportunity if you are looking for low-cost, cyclable storage of energy. “I believe they’re the most attractive solution in the long-term [for grid storage].”
,” he said.
After the Fort Carson flow battery is completed, Lockheed Martin said they would spend approximately two years testing it. Below is a video that explains the system in general.