https://evmagazine.com/articles/tesla-launches-first-all-ele...
But the linked article is pretty light on info, so I'll reserve judgement till more info comes to light.
It's not the best way to go for mainline track and not suitable for long distance high speed trains.
They’re also useful as a transition technology. The DART+ project in Ireland will use them for one line which will have the frequency for electrification (8 trains per direction per hour) and is already partially electrified, but is going to take a while to fully electrify (due to low bridges etc); once it’s electrified they’ll then likely be used in low-frequency regional routes.
(The realised project will use 750 uniform cars, about 200 of which will have batteries.)
Why did India build a high speed freight corridor with overhead power when they could have used batteries instead? Because the quantity of battery to power the trains doesn't exist, and overhead wires do.