Researchers have developed a new molten salt battery to be connected to the electricity grid in order to compensate for the intermittent production of renewable energies. Their invention is much cheaper to produce and use than other solutions already available commercially, thanks in particular to a much lower operating temperature.
You will also be interested
[EN VIDÉO] What are the 5 types of renewable energies? Solar energy can be thermal or photovoltaic. Water carries energy, when it flows in rivers, when it circulates in the ocean or when it agitates on the surface of the sea. The atmosphere is a giant thermal machine that wind turbines can tap into. Finally, under our feet, the heat of our planet is within reach. Here is the overview of what is commonly called renewable energies.
The renewable energies are not sufficient on their own to provide adequate nutrition for the power grid. Their operation is intermittent, and therefore requires storage system in order to collect energy at the peak of production, and distribute it when demand increases. In an article published in the journal Cell Reports Physical Science, researchers from Sandia Laboratories in the United States are detailing a new molten salt battery to address this issue.
One of the biggest flaws of batteries molten salt is their operating temperature. The most common, sodium-sulfur accumulators, require a temperature of 270 to 350 degrees Celsius. This new battery operates at only 110 ° C. This drastically reduces the cost, allowing the use of cheaper materials and thinner cables, and limiting the amount ofisolation necessary.
A battery that can be cooled without damage
The drums is composed on one side by sodium metallic liquid, and on the other a liquid mixture of sodium iodide and sodium chloride gallium. The researchers placed between the two a separator in ceramic which only lets the ions sodium. During discharge, metallic sodium releases electrons and sodium ions. Electrons convert sodium iodide into iodide ions, which react with sodium ions to create molten iodide salt.
The prototype was tested for eight months in an oven, with over 400 charge and discharge cycles. Because of pandemic, they had to stop the experiment for a month, allowing the battery to come to room temperature and the two liquids to solidify. It returned to normal operation after being reheated. This means that when it is connected to the electrical network and thatfailure occurs, it can be unloaded to continue supplying the network, then cooled. It will then be sufficient to heat it up and recharge it once the situation has been resolved, without a complex restart procedure and without it having suffered any damage.
A more compact and safer battery
The researchers also indicate that these batteries are not likely to catch fire. If the two liquids come into contact, no dangerous reaction occurs, unlike a batterie lithium-ion. In the event of an outside fire, the battery will be damaged but will not contribute to the flames.
This new drums is also much more compact. It produces 3.6 volts, or 40% more than molten salt batteries currently on the market. This means that fewer cells will be needed, limiting the number of connections and increasing storage density. It is also much cheaper to produce. However, researchers want to replace gallium chloride, a very expensive element that costs around 100 times more than table salt. They estimate that it will take 5-10 years before this battery is commercially available.
What you must remember
- Researchers have created a molten salt liquid battery
- This battery works at only 110 ° C
- It is much safer and cheaper to produce
Interested in what you just read?
.
