Imergy’s vanadium flow batteries in Australia

December 2023 Update: Imergy’s website is no longer operational and their batteries are not listed on the Clean Energy Council approved product list.

Now available in Australia, PNG and the Pacific Island through CoverTel Telecommunications Group, Imergy’s vanadium flow batteries are promising to raise the bar for energy storage system performance – while at the same time lowering operational costs dramatically over time.

California-based Imergy Power Systems has developed an exclusive process for producing high-performance flow batteries using recycled vanadium from mining slag, oil field sludge, fly ash and other forms of environmental waste. This achievement will have significant impacts on the growing energy storage industry.

First of all, by extracting vanadium from slag, Imergy will lower the cost of obtaining and processing vanadium (the principal active ingredient in many flow battery electrolytes) by 40% relative to competitors.

Site Picture 1 With SolarImergy ESP5 flow battery system with solar array.

Imergy say that its flow batteries will also be capable of storing more than twice as much energy per kilogram as conventional vanadium flow batteries. This will give rooftop solar system owners, large-scale solar plant developers, microgrid owners and other customers more flexibility and capacity for managing outages, curbing peak power or reducing demand charges.

The technology is also advantageous from an environmental perspective: it takes an existing waste product with little or no market value and repurposes it into a device that has the power to reduce carbon emissions and other pollutants.

Imergy flow battery technology

Imergy’s Energy Storage Platform (ESP) is based on vanadium redox flow battery technology, a cost-effective and reliable solution for energy storage requirements. Unlike many conventional batteries whose functional components (especially the electrolyte) are prone to degradation when the batteries are charged and discharged frequently or deeply, redox flow batteries can theoretically be cycled over and over again without limit – lending them to longer functional lives. This is thanks to the fact that the electrolytes in flow batteries do not break down over time in the same way that lead acid or even lithium-ion batteries do. (Read more about flow batteries here.)

There are many advantages to Imergy’s flow battery, but one of the most important features is its ability to be discharged to 100% depth of discharge (DoD). “Most people make the mistake of comparing – for example – a 5kWh lead-acid battery bank against a 5kWh Vanadium system,” says Covertel business manager Mario Cacchione.

“A 5kWh lead-acid battery cannot be fully discharged to 5kWh without killing it in a few hundred cycles. Furthermore, it cannot be run with rapid charging and it must be kept cool. The recharge time is also long, and life cycle is limited to about 1500 cycles even with a limit of 50% DoD. Imergy’s vanadium redox flow battery, on the other hand, can be cycled to 100% DoD without impairing its ability to hold a charge.

“In practice a lead-acid battery bank needs to be twice as large as an equivalent Imergy system. That is, in order to get 5kWh of usable energy out of a lead-acid battery bank, its capacity must actually be 10kWh. This means that both costs and space requirements double. And that’s not even counting the need for a battery management system – which is built into all of Imergy’s devices.”

Flow battery schematicSchematic of a flow battery.  (Image Credit: University of British Columbia)

Advantages of the Imergy Power System

Key features:

  • High energy density vanadium electrolyte
  • Safe, non-flammable, non-combustible
  • High power density cell stack with fast-charging capability
  • Integrated state-of-the-art electronics for control and power conditioning
  • Remote control and monitoring option

Key benefits:

  • Theoretically unlimited cycle life
  • Reliable and consistent power availability enabled by fast charge and discharge capability
  • Customized, separate power and capacity specifications for different applications
  • Durable operations in rugged, remote outdoor environments up to 55°C ambient

Imergy product range

Imergy has a range of products which can be deployed in residential, commercial, industrial, utility and telecom applications.

ESP5 Series

  • Applications: Residential, telecom & off-grid
  • Output Power: 5kW
  • Capacity Range: 15-30kWh at 100% depth of discharge
  • Download a data sheet: Imergy ESP5 (PDF)

Imergy ESP5ESP30 Series

  • Applications: Commercial, industrial, off-grid
  • Output Power: 15 – 45kW
  • Capacity Range: 120 – 200kWh at 100% depth of discharge
  • Dimensions: 20 x 8 x 8.5 ft (20 foot shipping container)

Download a data sheet: Imergy ESP30 (PDF)

Imergy ESP30ESP250 Series

  • Applications: Utility, renewables integration, mining, off-grid
  • Output Power: 250 kW
  • Capacity Range: 1MWh at 100% depth of discharge
  • Dimensions: 40 ft. container upper / 45 ft. container lower

Download a data sheet: Imergy ESP350 (PDF)

Imergy ESP250Contact CoverTel

Mario Cacchione, Business Manager

Tel: +61 3 9381 7888
Mob: +61 400 940 511

© 2015 Solar Choice Pty Ltd

Read more product reviews from Solar Choice


  1. Imergy. Has since filed bankruptcy protection…how many vanadium storage units do you have. Do you them in all sizes as per this site…and more importantly I wish to acuire one. Why do you advise to contact imergy directly. …please help with acuring one.. regards stace. From Queensland

    1. Hi Stace,

      This is an informative article – we do not stock Imergy’s products (or anyone’s products) for that matter, as we are a brokerage & comparison service. What is on offer in our system comes down to what products the installers in our network are offering.

      And yes, Imergy has filed bankruptcy and as we understand it there is not stock available in Aus at this point.

  2. I want a quote for a vanadium flow battery for a commercial installation in Hoppers Crossing, Victoria. Tyhe unit is to replace an existing storage system which is 40KWH. My phone number is 0419881577

  3. Hi, in regards to the flow batteries, why is power production limited to, in the case of ESP 30 series, 2-12 hours? Ideally, I would require power generation for some days continuously given a sufficient amount of charged electrolyte. There seem to be limitations that have not been indicated, please explain the situation. Also, where can I find approximate costs?

    Regards, Andrew.

  4. I am student i south Dakota state university, SD, USA. i have a project about energy management system in remote micro grid area. could you pleas give me some information about vanadium flow batteries :
    cost,battery life time and the datasheet
    thank you

    1. Hi Ali,

      I would recommend contacting Imergy directly with your request: or

      You can also download spec sheets about their various products in this article (spec sheets are linked to underneath each product).

      Good luck with your project.

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