The key to this new battery turned out to be an often bothersome green algae known as Cladophora.
The rest of TFA is speculative and, to my mind anyway, worth the 30 seconds it took to read. Without this one definitive sentence claiming this as more than a new thread to follow, it's just a piece about a potential new avenue into cellulose batteries.
While I definitely agree that bold claims do hurt their industries with unreal expectations, I know I usually am more forgiving than I would be to large industries like pharma or oil. It's not a fair or educated position, but I often attribute that kind of overzealousness in these articles to optimism and enthusiasm, whereas if it's a press release from a huge corp. I see it as manipulative and marketed. That's probably an unfair ideological position and I try to stay aware that I have that bias, but I don't feel I'm totally out to lunch feeling that way in general.
I always appreciate it when people point out these discrepancies, but I think there is a legitimate reason why it occurs. We should make note where it happens, but I don't feel like getting angry at the people who may have overstated how far along they are in achieving some of these goals. If it takes an outlook that makes them feel they're closer than they are to keep plugging away so they, or the scientists after them finally do make a breakthrough, I'm more than willing to tolerate the fact they tend to minimize the difficulties between where they currently are and where they claim they are heading.