Large Scale Redox Flow Battery (700 megawatt hours)
Posted on July 16, 2017 Comments (0)
Scientists and engineers in Germany have created the largest battery in the world with redox flow technology.
Redox flow batteries are liquid batteries. The Friedrich Schiller University of Jena has developed a new and forward-looking salt-free (brine) based metal-free redox flow battery. This new development will use salt caverns as energy storage.
A redox flow battery consists of two storage tanks and an electrochemical cell in which the reactions take place. Storage for solar and wind sources of power is an important challenge being explored in many ways today. Efforts such as this one provide a path to continue the rapid adoption of more solar and wind power.
In the electrochemical cell the two storage liquids – catholyte and anolyte – are separated from one another by a membrane. This prevents the large storage liquids from mixing with one another. The ions, however, can pass unimpeded through the membrane from one electrolyte solution into the other.
When charging the battery, the charging current ensures that electrons are deposited on the polymers of the anolyte. At the same time, the catholyte releases its electrons.
The charged catholyte and anolyte molecules are pumped from the cell into storage containers and replaced by uncharged ones. When the battery is discharged, the reaction is reversed. The anolyte molecules emit their electrons, which are available as electrical current.
Both charged electrolytes can be stored for several months. The maximum storage capacity of this redox-flow battery is limited only by the size of the storage containers for the electrolyte liquids.
The project is being ramped up now, going through a test phase before bringing the full system online; they are aiming to achieve this in 6 years. The electrical capacity of 700 megawatt hours will be enough to supply over 75,000 households with electricity for one day.