Battery-powered shipping is close to being economically sensible, depending on things like battery prices and how the price of pollution is accounted. However, it's still a massive engineering challenge.

Will there be at least one battery-powered electric cargo ship, of at least 500 TEU capacity, making routine commercial voyages of at least 1000 km length, before 2029?

If the ship has both battery-electric and fuel-based (combustion or fuel cell) power systems, it will be counted if the nominal battery-only range exceeds 1000 km and it is making routine voyages of at least 1000 km.