Frequently Asked Questions

If you have a question that is not listed below, please get in touch.

What are the basic differences between large lithium based batteries and vanadium redox flow batteries?

The vanadium redox flow battery (VRFB) uses a different method of storing energy than Li-ion batteries.

VRFBs use a circulating electrolyte solution of vanadium pentoxide to store the charge in tanks, while Li-ion batteries store all the charge inside the battery cell itself. VRFBs have lower energy density compared to Li-ion, but since the tanks can be scaled up to any size, have the ability to store a lot more total energy. Li-ion batteries are able to deliver very high power quickly, hence are very suitable for mobile applications such as electric vehicles.

VRFBs are energy batteries and therefore very suitable for storing large amounts of energy (particularly renewable energy) for later use. Because flow batteries can cycle more often and to greater depths of discharge (100%), they have a longer life than Li-ion batteries which eventually become less efficient when cycled too frequently.

Inherently, vanadium redox flow batteries are safer than Li-ion since they are not prone to the thermal runaway known to occur with Li-ion batteries.

Deliberate stack (contains 20 cells) short circuit testing shows no signs of failure or catastrophic temperature rise:

How much does a vanadium redox flow battery cost?

Each requirement for energy storage is different and the solution is therefore tailored to the particular client. When we can see that our products offer the right solution for a client, we can then provide a quote.

Some clients require a battery to store energy from existing renewable energy generation, some require a solution which includes generation, others want to charge the battery using off-peak standard power. We have on-grid and off-grid solutions and there are many variables. We are happy to discuss individual requirements to see if we have a solution that is appropriate.

How far advanced is development of the vanadium redox flow batteries?

VRFBs have been in development for decades. The technology was actually born out of the University of New South Wales, which has a battery installed at its campus.

Companies worldwide have been implementing large-scale batteries for a number of years – Sumitomo is one example that has completed numerous installations while the CellCube has over 100 installations worldwide.

Other manufacturers include SCHMID, UET, redT Energy, Rongke Power, Pu Neng, Avalon Battery, Vionx and Thyssenkrupp. While in development for many years, VRFBs have never before existed in a market with the current installed capacity and high demand for renewable energy as exists today.

Can the vanadium in the batteries be recycled?

The batteries have a life of 20+ years.

The electrolyte can be removed after this time, cleaned by filtration if necessary and re-used.

Who is VSUN Energy partnering with in this strategy?

VSUN Energy is involved with a range of different stakeholders throughout the battery storage market. This includes battery makers, renewable installers and electrolyte producers.

  • We are collaborating with Sun Connect which is currently one of the five largest installers of commercial solar in Australia and has installed over 9MW of commercial solar systems.
  • We sell batteries from a wide variety of manufacturers including redT Energy, Schmid, UET, CellCube, FBICRC and Murdoch University.
  • We are collaborating with C-Tech on the development of vanadium electrolyte production capability in Australia through both stand-alone and mine-attached facilities.
  • We have also appointed the vanadium battery inventor, Emeritus Professor Maria Skyllas-Kazacos, as a consultant to the group. We benefit greatly from her experience and expertise in the vanadium battery field.
  • We have MOUs with EPC Technologies and BuildingIQ to assist each other in the energy market.
  • We work closely with a variety of solar installers and have contacts in the wind industry.

The company is open to collaboration with all energy market participants.

What is the structure of the partner agreements?

The partner agreements allow for co-operation in the development of the vanadium battery market in Australia.

This includes defining sales opportunities, exploring electrolyte manufacture and sale as well as developing long term sustainable sources of vanadium supply.

Australian Vanadium Limited is confident that these partnerships will help to diversify risk and include key skills, while also providing positive exposure to early cash flows and potential upside from a growing market.

When do you expect the next battery sale?

The first battery has been installed in Western Australia. Further sales leads have been developed and are at a range of stages, from initial discussions around requirements and solutions to submitted proposals. Potential customers are emerging from a range of backgrounds, including mining and exploration companies, the farming community and industrial sites.

How is VSUN Energy funded?

Australian Vanadium Limited is a listed company with cash on hand and allocated to VSUN Energy to fund the early stages of market development. The company will actively assess other opportunities for future funding but we are confident shareholders will see the positive opportunity which exists in the energy storage market.

Do you provide a residential solution?

We are able to offer a 5kW/15kWh, 5kW/30kWh or 5kW/45kWh solution from Schmid for off-grid sites which needs to be installed indoors.  This will be approved for on-grid sites soon.

For a 5kW/10kWh and upwards outdoor installation we offer Visblue and soon to be available Volterion products.

In a multi-residential situation, we can offer a variety of solutions.

To keep up to date on this sector, please look out for releases by our listed parent company, Australian Vanadium Limited, (ASX: AVL) and via social media.

Is it environmentally sound to use a substance which has to be mined?

Vanadium, like copper, aluminium, iron, lithium, are all metals that mostly need to be extracted from the earth’s crust by mining. All of these metals form part of everyday technology including batteries. Modern environmental laws in Australia demand that mining is conducted under strict conditions and within government regulations to reduce environmental damage and ensure the rehabilitation of any land disturbed by mining. Vanadium, if used in VRFB as vanadium electrolyte, is anticipated to have a long life of up to 20 years in each battery system. If a battery system is de-commissioned for any reason, the vanadium solution and all the contained metal can be 100% reclaimed and re-used elsewhere.

Can you explain some of the terminology used?

Cycling – cycling means charging and discharging the battery.

100% discharge capability means that the battery can be fully discharged to zero without damage.

Redox is an abbreviation where Red stands for reduction = gain of electrons, while Ox stands for oxidation = loss of electrons.

SOC – State of Charge

Cell – A closed electrochemical power source. The minimum unit of a battery. The FB10-100 has 10 modules of 20 cells plus 1 OCV cell for SOC measurement for a total of 201 cells. The Tesla Powerwall 85kWh has 16modules of 444 cells for a total of 7,104 cells which all need to be monitored. Larger utility scale systems will also require cell voltage balancing, because when cells are in series, the performance of the overall system can be limited by the performance of the weakest cell. In grid scale applications, when cells are in series, performance of the whole system can be limited by the performance of the weakest cell. Source.

Cycle life – the number of charges and discharges a cell can perform before its capacity drops to 80% of its initial specified capacity.  For a flow battery this is 20 years because the capacity loss is 1% per year or 10% over 10 years (this is where the 20 year lifetime number comes from).

Energy throughput – the total amount of energy in Watthours (Wh) which can be taken out of a rechargeable battery over all the cycles in its lifetime before its capacity reduces to 80% of its initial capacity when new.

For a more comprehensive list of energy related meanings and acronyms, click here.