Salt batteries 16-03-2023
-What are salt batteries
Salt batteries, also known as salt accumulators, are devices that store energy: the goal, so to speak, is the same as lithium batteries, but the internal chemical composition changes. This type of accumulator is called “salt” due to the very high presence of sodium chloride (32%): sodium is an element of the periodic table which, compared to the lithium of canonical batteries, is easier to find and is also recyclable, even if it has a
However, all that glitters is not gold: as we mentioned at the beginning, not only are salt batteries more expensive than lithium ones, but they also have a strong nickel component (20%), by far the element most present after sodium and followed to a lesser extent by ceramics, iron, copper and various elements. Salt batteries
Nickel, compared to sodium, is more difficult to find and requires special precautions in the context of disposal so as not to impact nature.
Composition and operation
But how are salt batteries specifically made? Forgive us for the brief technical parenthesis, it is necessary to better understand this technology.
Each cell in the charged state sees a positive electrode of copper and nickel chloride (cathode) and a negative one of liquid sodium (anode): separating the two electrodes is a ceramic tube called beta-aluminate ceramic electrolyte. The contact between the latter and the positive electrode is ensured by a molten secondary electrolyte. We won’t go into too many details, however know that the operation is based on reaching high temperatures to melt a specific element, in this case sodium (97.8°C): essentially, salt batteries work with a range between 270°C and 350°C. Salt batteries
Where do salt batteries come from?
Despite their rather recent use, salt batteries were actually born in the distant 1980s in South Africa: behind this intuition is Zeolite Battery Research (Zebra) which invents the Zebra Battery. A very old story, therefore, which sees the company in question change various properties, an element that in fact greatly slows down the economic investments and the market development of this type of technology. An important turning point came with the Italian company Elettra 1938, which managed to produce these components in series under the name of FZSoNick, making them adopted by some bus companies.
Also in the rest of the world salt batteries find several companies very interested in their production: the best known example is that of CATL, a Chinese company considered the largest battery manufacturer in the world. Even the Italian company AMG Italian Energy Storage, despite its young age, is making an important contribution to the widespread development of this technology.
Pros and cons of batteries
So what are the advantages and disadvantages of this technology? Why should you invest in it? Salt batteries, as already indicated, constitute an extremely valid solution for moving towards energy sustainability: in addition to being recyclable, they have a long life, do not require maintenance, do not present a fire risk and are not toxic to humans . In addition, they can also operate at low ambient temperatures due to the excellent thermal insulation and, not being affected by temperature variations, they have a constant effectiveness that does not decrease with prolonged use. An extremely interesting and positive picture, therefore.
Unfortunately, there are also some disadvantages: a turning point when discharged, salt batteries need about 10-12 hours to return to the internal operating temperature, making them unsuitable for occasional and fast charges. In addition, the dimensions do not allow the use of small devices (such as cell phones) and there is not yet a capillary and tested distribution chain like that of lithium batteries.