The solid state batteries which have been made so far as prototypes, not scaled up for production, weigh around 1/3rd of current lithium-ion.Odd that I read somewhere in my vast myriad of searches that solid state batteries were heavier...I guess they are just twice the cost right now and take more raw materials to make them.
I can see the real need for battery recycling centers to be regional in order to cut down on shipping spent batteries on roads and railways...
We currently have recycling centers in our regions so perhaps this can be one more addition to them.
I would say solid state batteries for the masses are a long ways off.
One of the videos I attached explains why EV are not gathering popularity...there's conjecture that they were rushed out and their support base was not put into place before hand requiring the game of catch up to be played which pisses off consumers.
There is no cost yet, as they have not scaled up production.
Long way off is around 4 years.