Zinc–bromine battery

Zinc–bromine battery
Specific energy60–85 W·h/kg
Energy density15–65 W·h/L (56–230 kJ/L)
Charge/discharge efficiency75.9%
Energy/consumer-priceUS$400/kW·h (US$0.11/kJ)
Cycle durability>6,000 cycles
Nominal cell voltage1.8 V

A zinc-bromine battery is a rechargeable battery system that uses the reaction between zinc metal and bromine to produce electric current, with an electrolyte composed of an aqueous solution of zinc bromide. Zinc has long been used as the negative electrode of primary cells. It is a widely available, relatively inexpensive metal. It is rather stable in contact with neutral and alkaline aqueous solutions. For this reason, it is used today in zinc–carbon and alkaline primaries.

The leading potential application is stationary energy storage, either for the grid, or for domestic or stand-alone power systems. The aqueous electrolyte makes the system less prone to overheating and fire compared with lithium-ion battery systems.