EOS Energy (zinc-bromide grid-scale batteries), just christened their first automated manufacturing line and have entered mass production.
If they're still rolling out new manufacturing lines, they are clearly still kicking and have investors who believe they have a viable product.
Did they have to move on from one technology? I mean I've never heard of them before but if you say so, that's not really that surprising with how fast with battery technology is evolving.
Use of bromine doesn't sound terribly practical.