Batteries International article

VSUN Energy, the wholly-owned subsidiary of mining company Australian Vanadium, announced on April 12 it was in negotiations with the designer of a residential vanadium redox flow battery that will provide an alternative to the lithium-based Tesla Powerwall.

VSUN Energy business development manager Sam McGahan told BESB that negotiations with the holder of the battery design for home storage were under way, and a study had been commissioned to look at the timescale and market size in Australia.

“What we would like to do is to manufacture in Australia, so we need to partner with someone who has manufacturing expertise,” she said.

“Other angles we’re investigating are things such as having a larger battery at the substation level which can be used to soak up excess production from the suburb and then can be drawn upon by the householders. This would involve a product such as Reposit or Power Ledger to manage the ownership of the energy and would enable people to trade their generated energy.”

Reposit and Power Ledger are two software systems that can be fitted to solar panels and allow consumers to trade surplus energy.

McGahan said the main benefits of vanadium redox flow batteries over lithium are they are non-flammable, have a lifespan of more than 20 years, do not degrade, can be recycled as many times as required and provide more hours of storage.

“The state of charge is measured across one body of liquid, rather than multiple cells. It’s a much simpler set-up,” she said.

To date, VSun’s smallest product was a 10kW/100kWh battery that would be suitable for farms and industrial premises. The new design is more suitable for a residential property, at 5kW/20kWh.

Vanadium redox flow batteries have a bright outlook, according to market analysts.

One report, by IDTechEx, says that the expiry of a number of patents related to redox flow batteries in 2006 has sparked interest in the market, which will grow to an estimated $4 billion by 2027.

The report says potentially the largest battery in the world, at 800 MWh, is being built in Dalian, northwestern China and will be powered entirely by redox flow batteries.