There's other technologies that they're trialing for boats that seem silly but works on paper at least. We're currently building a ferry with a massive flywheel to store lots of rotational inertia to convert to electricity, which on the face of it is bonkers but again, the maths says it's good.
It's my impression that a lot of sulfur and other "advanced" chemistries are held up by operating restrictions like temperature for consumer vehicles, but industrial transport vehicles might not have such requirements because they have constant output.
Although it would be better if the battery is at the bottom of the ship so there would also need to be some sort of air exhaust system for when that happens, hopefully one that prevents the fumes from reaching the passengers at all but I don't think that would be possible without a chimney.