
Iron salt
technology
Unrivaled low costs, high availability of the iron-based storage medium and high temperature resistance make iron-salt technology the storage technology of the future.
World’s most cost-efficient battery technology
Thanks to the unrivaled low cost and unlimited material availability of the iron-based storage medium, iron salt technology has great potential to shape the future of battery storage beyond lithium. For 100% renewable energy around the clock and for a fairer and cleaner world for future generations.
How does it work?
The heart of an iron salt energy storage system is the redox flow battery unit. It is based on two battery half-cells through which liquid electrolyte is pumped in independent cycles. The half-cells are separated by a membrane and together form the full battery cell. The electrolyte is enriched with iron chloride. During charging or discharging, ions and electrons are transferred between the two half-cells, storing, or releasing energy in the electrolyte. In the uncharged state, both cells have identical oxidation levels; charging leads to reducing the electrolyte in one half-cell and oxidizing electrolyte in the other. Within the negative half-cell, the iron in the electrolyte is deposited as metal on the electrode. The battery capacity is dependent on the iron deposition: an increasing amount of iron deposition leads to a higher capacity. The reaction is fully reversible, and iron is re-dissolved in the electrolyte during discharging.
Advantages of the iron salt technology

Pioneering innovations
VoltStorage continuously strives to challenge the status quo and set new standards in storage technology. With the development of the revolutionary iron salt storage technology, VoltStorage is making an important contribution to the development of groundbreaking solutions for Long Duration Batteries. You can find out more about VoltStorage’s current research and development in the Innovation Lab.