Around 10 years ago, I did a bunch of research into battery banks for an off-grid solar installation. I looked at probably a dozen very different battery types (some of which were 'coming to market soon', boy were all those a dead end). The option that seemed to be the best choice overall was flooded lead acid, which surprised me.

It's very interesting that even after all the improvements in battery tech since then, this still appears to be the case. I wonder how much longer it will hold true?