LPI - The Next Lithium Producer in Chile, page-2292

It's interesting that the Edison Research paper from March 2022 mentions the following:

While the Maricunga project is at a relatively advanced stage and noting a non-binding MOU with Mitsui, it is yet to secure a binding offtake or a strategic partner within the battery value chain. We note that the use of the salt removal plant is new in lithium brine processing, although the design of the plant is based on established technology and the use of evaporators and crystallisers is common in the chemical industry. The process was developed by GEA Messo (a well-known German engineering company), and according to the BFS was able to produce battery-grade carbonate from Maricunga’s brine (in particular, the original samples produced in 2018 indicated a 99.5% purity). The JV has undertaken a series of product tests at a semi pilot plant scale. However, given the novel processing approach for brines, additional product testing might be required to secure the offtake.

Seems the battery grade results were key to the offtake and they let Edison know a year ago.