Water-based battery: clean and affordable alternative
The AquaBattery is a fairly simple battery for power storage. Because of its size, this experimental water-based battery is especially suitable for home applications to store power generated by solar panels.
At the Delft University of Technology, Emil Goosen (one of the founders of the Aquabattery company), develops the most environmentally friendly battery in the world. This battery is meant to store solar or wind power.
Because this battery is very large with its twenty plastic containers of one cubic meter, it is too big to be used in a car. However, it is very eco-friendly because there is only clean water and kitchen salt in it. No acids, no cobalt, or even lithium is being used.
How does it work?
With an electric current on the brackish water the battery is charged. The salt ions (electrically charged particles) are pulled through a membrane (say: ion sieve).
The water cannot pass through it, but the salt ions can. In one part the salt accumulates to concentrations comparable to those in the Dead Sea, and fresh water remains in the other container.
When the battery is charged, the process can be reversed: salt and sweet are brought back together again, resulting in an electric current.
Battery will be launched in 3 years
Today, AquaBattery already employs nine people, but it still takes three years before the battery can enter the market. Until then the company mainly runs on subsidies and contributions from interested companies, such as grid manager, Enexis, and membrane manufacturer, Fuji. Extra money is very welcome.
The company is competing in the GreenChallenge of the Postcodeloterij (Dutch national lottery company). AquaBattery hopes to win the grand prize of half a million euro.
“However, the real battle is not about half a million, but about a global market. The water battery is cheap; salt and water are everywhere, and the battery lasts a long time”, Goosen says.
Pros and cons
The water battery is also easily adaptable. A regular battery has a fixed storage capacity and a maximum current that can come out per second. If you want different characteristics, you need a different battery.
The AquaBattery can be changed to give more power or more storage capacity if needed. The biggest problem is its size, the battery still needs to be reduced in size by 70%.