The main idea here is that we won’t run out of raw materials very easily when using stuff that’s relatively cheap and abundant. Well at least the ions are. Who knows what the anode and cathode are made of. Probably the usual materials; otherwise they would have mentioned it. If they still use cobalt in the cathode, you can’t really avoid the ethical questions that come with it.

Producing all the other materials can be rather energy intensive depending on the method used, so it depends. If you buy your metals from a country with hardly any environmental regulation, you can be pretty sure they don’t give a dingo’s kidney as to how many trees are chopped down and how many puppies are thrown in a furnace to get the next shipment of metals delivered.

Also, the electrolyte could be more or less harmful to humans and the environment. As far as the environmental impact is concerned, these batteries probably come with all the usual issues. Currently there just aren’t any perfect solutions commercially available. Regardless, this seems like a step in the right direction IMO.