Well my guess is we are talking 10 to 20 years if ever. I expect more out of the electric battery pack cars.
Battery packs are good for cars and will also take 10 to 20 years. But Battery packs are impracticable for trains and long haul trucks. Switching to a large percentage would be 50 years plus or minus 10 years.
Now the next question is how do you pay for the roads with less fuel tax revenues ?