German flow battery developer VoltStorage has secured €24 million ($24 million) in Series C financing from the US power generation developer Cummins.
The cash will go toward the development of new iron salt battery for commercial and agricultural enterprises.
In addition, product development of the iron salt battery will be accelerated towards commercialisation with the Munich-headquartered firm planning to expand its team and the company’s activities.
Over the past five years, VoltStorage has received funding from: Korys, EIT InnoEnergy, Bayern Kapital, SOSV, Energie 360° and Business Angels led by Matthias Willenbacher.
How the battery works
An iron salt energy storage system is based on two battery half-cells through which liquid electrolyte— that is enriched with iron chloride— is pumped in independent cycles.
During cycling, ions and electrons are transferred between the two half-cells, storing, or releasing energy in the electrolyte with the battery capacity dependent on the iron deposition— increasing iron deposition leads to a higher capacity.
In the uncharged state, both cells have identical oxidation levels; charging leads to reducing the electrolyte in one half-cell and oxidising electrolyte in the other.
Within the negative half-cell, the iron in the electrolyte is deposited as metal on the electrode.
