Electrified rail is expensive and has safety issues. It’s the best option for long distances for sure, but here in the UK we are still trying to electrify the main rail lines, the branch lines and city lines aren’t even in the cards. Being able to recharge trains at stations with rapid charging is the best option for branch and commuter rail services not already on electrified rail (most of them). If we can do that using something other than lithium batteries that would be great. Sodium seems promising. Also I am in Europe you muppet. It also doesn’t solve grid scale storage, which is something we need. I am hoping iron oxide batteries work out for the grid scale storage tbh.