Electric Fuel Energy of Israel claims over 10 hour discharge for its iron flow battery
- Electric Fuel Energy (EFE), an Israeli company owned by Arotech Corp. of the U.S., says its flow battery technology can sustain discharge for 10 hours or more.
EFE says its proprietary 150-kW, iron anode and ferro-ferricyanide aqueous couple cathode can deliver storage at $250 to $300 per kilowatt-hour.
EFE is targeting developing economies and isolated markets such as island communities and hopes to have a demonstration project in operation by year end with four more added in 2017 and 2018 and a fully commercial project under way in 2019.
Vanadium is to flow batteries what lithium-ion is to solid state batteries. But if vanadium could be replaced with a cheaper and safer alternative, lower cost flow batteries could gain some of the 70% market share that grid connected li-ion batteries now enjoy.
EFE says it has managed to get its iron anode and ferro-ferricyanide aqueous couple cathode to “work together” and is busy building its first production facility in Israel with the aim of producing batteries that cost between $250/kWh and $300/kWh.
Flow batteries generate power by pumping electrolytes from storage tanks to a central stack where the interchange between positive and negative electrolytes creates an electrical charge.
Because the electrolytes can be returned to their respective storage tanks, flow batteries have a more flexible and resilient cycling characteristics than solid state batteries. They can withstand deeper discharge cycles and longer life cycles, making them better suited for long-duration applications than most solid state batteries. But flow batteries also have lower efficiencies, in the 75% to 80% range, than li-ion batteries, which have efficiency levels in the high 90% range.
Speaking to Greentech Media, Dean Frankel, an analyst at Lux Research, said EFE’s target should not be dismissed out of hand, but that is “very aggressive,” especially when it applies to a fully installed unit that includes installer profit, inverters, shipping and the cost of land.
“For a system, without power electronics and without installation, it is believable but still aggressive,” Frankel said.
In addition, EFE is not the only company working on improving flow battery design. Several companies are working on improving flow battery chemistry with the aim of bring the technology closer to mass commercialization. Companies such as UniEnergy, Imergy and CellCube are working on vanadium batteries. Companies such as EnerVault and Primus Power are working on iron chromium is the chemistry, and EnSync Energy Systems and Redflow are specializing in zinc-bromine technology.
EFE says its iron flow battery avoids plating and dendrite formation, which can add to maintenance costs. The company also says its chemistry is ecologically sound and safe.
“The Iron Flow Battery offers superior safety and sound environmental characteristics ... in sharp contrast to batteries based on bromine, vanadium or strong acids," its website reads.
Correction: A previous version of this article referred to energy storage developer EnSync Energy Systems by its former name ZBB. That is incorrect. The company changed its name to EnSync Energy Systems in July 2015.
Follow Peter Maloney on Twitter