A surprising breakthrough could help sodium-ion batteries rival lithium—and even turn seawater into drinking water. Scientists discovered that keeping water inside a key battery material, instead of removing it as traditionally done, dramatically boosts performance. The “wet” version stores nearly twice as much charge, charges faster, and remains stable for hundreds of cycles, placing it among the top-performing sodium battery materials ever reported.
R&d on these I’m guessing takes a little while. And it greatly depends on what niche they fill. Like the poster above said these might have lower density. For applications that move, that’s not usually good. How sensitive are they to hot and cold? That could necessitate thermal management.