Here is an all-electric cargo ship with a payload of 1,000 tonnes, which recently was tested at the Yangtze River section in Changzhou (the longest river in China).
It's named "Zhongtiandianyun 001" and with a 1,458 kWh lithium-ion battery (plus ultracapacitors) it has a range of some 50 km (31 miles) on a charge.
Recharging takes about 2.5 hours provided you can find some serious DC power (like several hundred kW).
We are not aware of how much advanced the Chinese electrification of the ships is, but for sure it's taking off and hopefully, all diesel units will be replaced with EVs over time.
Electrification of ships moves forward also in other countries and we already saw pretty big units, with batteries of several MWh each.
Source: Xinhua via Green Car Congress