Exchangable_Battery_Electric cars

There are constraints for using electric cars. The main constraint is  charging time  of the batteries on the road.  Is it difficult  to exchange the used batteries for

charged batteries at battery stations ? . We could have   battery stations   on the road like  having gas stations now.  Of course I am not against  doing  research  to find the fastest method of charging the batteries  , quickly chargeable material etc. However  pencil is the best  and cheapest tool  to write in the Mars


We may have constraints  to implement battery stations on the road .  You may write to me   sun.suthasun@gmail.com