Redflow is an Australian company developing zinc-bromide redox flow batteries. The products are based on a 10kWh module, the ZBM3.
Redflow zinc-bromide redox flow batteries
Batteries are a mode of electricity storage with several problems: they require a lot of materials, there are safety issues (risk of fire) and they are not suitable for long-term storage. A new battery technology, storing electricity in electrolytes, is currently being developed: redox flow batteries. Redflow proposes one using a zinc solution and a bromide solution to store electricity.
They offer their technology in three formats: a small module, ZBM3, a medium-sized module (the size of a small car) and a large module, the size of a container.
ZBM3 flow battery, a small module
The ZBM3 flow battery is a very small battery, weighing less than a m3 (but still 240kg with electrolyte), 3kW (with a maximum of 5kW), 10kWh capacity and a claimed efficiency of 80%. Longevity is said to be 36,500kWh stored (3650 cycles at 100%) or 10 years. They operate at room temperature (10-45°C) and at altitudes of up to 2000m.
It is these 10kWh modules of which the other modules are composed.
Previously, they marketed a small “Zcell” module for private customers, which seems to have been discontinued. This was a 10kWh battery that cost around 12600 Australian dollars.
Quadpod, a car-sized module
The Quadpod is made up of 4 ZBM batteries. They are 2.27m long, 1.15m wide and 1.25m high. They therefore have a capacity of 40kWh and a power of 12kW (which can be increased to 20kW).
Energy pod200: a battery the size of a container
This is the module for industrial storage farms. These are 6.25-tonne containers designed to hold 20 ZBM3 batteries connected in parallel. They have a capacity of 200kWh and 60kW, which can be increased to 100kW.
Financing and development of Redflow
Redflow was founded in 2005 by brothers Chris and Alex Winter. It went public in 2010. It has around 90 employees and is based in Brisbane, Australia.
They sold 2MWh of these systems in California, atAnaergia’s Rialto Bioenergy Facility, in March 2021.
In January 2023, the company announced the integration of its system with the Deye hybrid inverter.
The company was worth around $60 million in August 2022.
- Interview with the founder in 2022: https://pv-magazine-usa.com/2022/09/19/redflow-targets-us-market-with-lithium-ion-battery-alternative/