Above: the circular economy. Source – Deloitte LLP
Principally, battery recyclability. Recent tests have proven that it is possible to recover 97% of the vanadium used in the electrolyte itself. Given that the other materials used to make a vanadium flow battery are also fully recyclable, this means there is virtually no waste created at end-of-life and the vanadium can be used either for other purposes or to be made back into electrolyte again. Lithium batteries, however, are much more difficult to recycle and it is worth noting that EVs alone are expected to create 235,000 tonnes of battery material waste by 2040, eight times more than by 2030.
Secondly, in addition to extracting vanadium from the ground through mining, it can also be sourced as a by-product from existing production methods. Currently, much vanadium is recovered as a co-product with iron processed for steel production. It can also be recovered as a secondary product from fly ash, petroleum residues, alumina slag, and from the recycling of spent catalysts used in some crude oil refining. Using vanadium from this secondary production method means we can be more efficient with our use of resources and reduce the amount of “virgin raw materials” in our batteries.
The final major benefit vanadium brings to our batteries is safety. When mixed into an electrolyte, which in our case is around 70% water, a vanadium flow battery has absolutely no fire risk (check out this video demonstration). This makes it ideal for grid scale battery storage installations where safety is paramount (and often required to be demonstrated by planning/permitting authorities). The lack of any fire risk also means that our batteries don’t require large temperature regulation and fire suppression systems, unlike lithium-ion batteries, and they can easily be stacked on top of each other and side by side, maximising the use of space on sites.