ESS Inc., a ten-year-old, Oregon-based company has developed a low-cost, iron-flow battery for long-duration energy backup requirements of up to 12 hours per battery pack. Iron-flow batteries combine iron, salt, and a water-based electrolyte to produce reliable electricity storage suitable for utilities and industrial sites where flexible energy capacity is needed.
The battery's four components include two electrodes, the electrolyte and a separator. A pump keeps the electrolyte flowing as charged particles shuffle between the electrodes while the separator prevents a short circuit. Each battery comes packed into a shipping container. These can be daisy-chained to other containers to rapidly expand energy storage for any site. That's why you can see the efficacy of use for utility and large industrial and commercial operations.