VRFB Operating Principle

The Vanadium Redox Flow Battery is an advanced and innovative flow battery technology. Different oxidation states of the dissolved vanadium ions in the electrolyte (V2+, V3+, V4+, V5+) store or deliver electric energy. Depending on the current demand, energy is either stored in the electrolyte (charging) or fed into the grid/network (discharging).


VRFB Technology

The Vanadium Redox Flow Battery (VRFB from s stands for progressive and innovative flow battery technology. Different oxidation states of dissolved vanadium ions in the electrolyte (V2+, V3+, V4+, V5+) store or deliver electric energy. The electrolyte is continuously fed from a tank system into the reaction cell. Depending on the current demand, energy is stored in the electrolyte (battery charging) or fed into the grid/network (battery discharging). Because the electrolyte flow direction does not have to change when loading and unloading, the VRFB is very fast in the response time (less than 20ms). It can be switched between charging and discharging under full load. When the system is in standby mode, only a maximum discharge of the stack takes place. In the electrolytic tank there is no discharge taking place until the electrolyte will be pumped again through the stack by turning on the pumps.

The SCHMID EverFlow® energy storage technology is designed in such a way, that the flow rate of the pumps is adjusted according to the necessary energy amount needed at the current moment in order to achieve the best efficiency possible.

Vanadium Redox Flow Battery, only one element (Vanadium) in the electrolyte for storing energy:

  • A chemical element with the symbol V and atomic number 23
  • Unique in the periodic table and noteworthy for the accessibility of four adjacent oxidation states: 2+ | 3+ | 4+ | 5+ This allows the storage of energy with only one element.
  • Making use of the different oxidation states of just one element in order to store electrical energy. During the process of charging and discharging a color change can be observed and thanks to the OCV cell the SCHMID EverFlow® systems can determine the exact State of Charge (SoC) at any time.

Watch it on youtube-icon_30x30

SCHMID and VRFB
Since 2010 SCHMID Energy Systems has been active in research and development of the EverFlow® energy storage solution based on Vanadium. All components, including the cell and stack production, are 100% made by SCHMID and are manufactured and assembled in Freudenstadt in the Black Forest Germany. With more than 50 years of experience in the manufacture of wet chemical systems SCHMID has the necessary competence and experience for the production of EverFlow® storage solutions – Expect Solutions!

History of VRFB
The basics for Redox Flow Cells were developed in the middle of the 20th century by Walther Kangro at the Technical University of Braunschweig in Germany, when the possibilities of energy storage with redox couples were tested for the first time. In the 1970s, NASA dealt with the development of this technology. The pure vanadium solution was first proposed in 1978 and developed in the 1980s at the University of New South Wales.