Comparing Vanadium Redox-Flow Batteries and Zinc-Bromine Flow Batteries

October 15, 2021

Introduction

With the increasing demand for renewable energy, energy storage technologies have become crucial in ensuring a stable and reliable power supply. Two types of flow batteries, the Vanadium Redox-Flow Battery (VRB) and the Zinc-Bromine Flow Battery (ZBFB), have gained popularity due to their promising performance and cost-effectiveness. In this blog post, we will compare these two technologies to help you choose the best option for your energy storage needs.

Energy Density

One of the most important factors in selecting an energy storage technology is its energy density, or the amount of energy that can be stored per unit volume. The energy density of VRB ranges from 12 to 25 Wh/l, while ZBFB has an energy density of around 30 Wh/l.

In terms of capacity, ZBFB has an advantage over VRB as it can store up to 500 kWh, while VRB can only hold up to 200 kWh.

Verdict: Zinc-Bromine Flow Batteries have a higher energy density and larger capacity than Vanadium Redox-Flow Batteries.

Efficiency

Efficiency is another crucial factor to consider when selecting an energy storage technology. It is measured by the ratio of the energy output to the energy input. The roundtrip efficiency of VRB is around 70-80%, while ZBFB has an efficiency of 75-80%.

Verdict: Both technologies have similar efficiency, with Zinc-Bromine Flow Batteries slightly edging ahead.

Lifespan

The lifespan of energy storage technologies is an important consideration, as replacing them can be both expensive and time-consuming. VRB has a lifespan of around 20 years, while ZBFB can last up to 15 years.

Verdict: Vanadium Redox-Flow Batteries have a longer lifespan than Zinc-Bromine Flow Batteries.

Cost

Finally, the cost of the technology is an important factor to consider, as it can determine the level of investment required. VRB is generally more expensive than ZBFB, with a cost of around $350-$450 per kWh, while ZBFB costs around $200-$300 per kWh.

Verdict: Zinc-Bromine Flow Batteries are cheaper than Vanadium Redox-Flow Batteries.

Conclusion

In conclusion, both Vanadium Redox-Flow Batteries and Zinc-Bromine Flow Batteries show promise as energy storage technologies, with each having its own advantages and disadvantages. If you require a high energy density and large capacity, ZBFB is the way to go. However, if you prioritize a longer lifespan, VRB is the best option. In terms of cost, ZBFB is the more economical choice.

References

Kaur, P. (2020). Efficiency and cost analysis of vanadium redox flow battery-acidic electrolyte and zinc-bromine flow battery for energy storage applications. Journal of Renewable and Sustainable Energy Reviews, 119, 109692.
Zhang, Y., Yang, D., & Wang, Q. (2017). Zinc-bromine flow battery for energy storage: A review. Journal of Renewable and Sustainable Energy Reviews, 67, 276-286.