The difference is obviously size, but also the environment the batteries are intended to work in. I don’t know enough about the details of the actual technology of individual batteries to say for sure if there is any major difference between automotive and maritime use, but from what I read and hear the development is happening fast and furious to improve both efficiency and safety on all sides.
Large capacity battery banks are now used both on ferries and other short haul vessels as main propulsion. The have to be recharged quickly at the short stops (5 -10 min.) at each stop on the route to make it operationally feasible and emission free. (Contact free charging is the latest as far as I know)
On cruise ships and some larger ferries they use batteries for propulsion for short periods when in sensitive areas, but charging is from their DG, so not exactly “emission free”, only reduced.
More and more uses for battery power in the maritime world is found and developed, but nobody is talking about battery powered ships crossing oceans. (Yet?)