Article from renew economy, shows how well redflow is known, with an experimental "aqueous zinc" battery showing promise and look at all the reasons while it may be a better fit for grid storage. it is a shame that a major Australian renewable energy promoting organization can't produce an article stating that a commercially viable alternative to Lithium based batteries, made in Australia already exists.
https://reneweconomy.com.au/zinc-battery-breakthrough-as-researchers-fix-spiky-crystal-problem/Zinc battery breakthrough as researchers fix spiky crystal problem | RenewEconomyExtract from article.
Whether they could be competitive with existing alternatives however, requires more research. Currently, research into AZBs shows they’re a viable alternative to large-scale lithium ion batteries with an energy density of between 50–200 Wh/kg, compared to 70–250 Wh/kg, but they don’t have as good power output.“A safe and affordable AZB technology will accelerate renewable energy integration, enable smart grid technologies for better management of energy distribution, load balancing, and demand response, support the establishment of microgrids powered by renewable energy sources for remote communities, and may provide a cost-effective and reliable storage option for industries like mining, construction, and telecommunications.”In bushfire-prone Australia, AZBs’ aqueous salt solution electrolyte promises less fire risk than lithium, and it’s abundant, cheap, potentially fully recyclable, and can be made in ambient temperatures rather than in cold room
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