How fast could EV sales grow?

In other words, what's the upper limit if we tried hard, perhaps because of an oil supply shock?

We could do it pretty quickly.

Heck, EVs of various sorts (including hybrid EVs) are at 4% of new car sales in 2014, and that could be doubled overnight with car maker unused capacity. After that, I’d estimate it could grow by 40% per year.  That would allow a doubling every 2 years, which means that it would take about 7 years to get to 90% market share. At that point about 27% of the cars on the road would be electric, and it would take another 3 years to get to 50%, which would probably account for 75% of total Vehicle Miles Traveled.

 Now, obviously that’s incredibly simplistic, but it gives you an idea of the timeline of an aggressive rollout.

I’m much more worried about Climate Change where the lag time for GHGs in the atmosphere is decades and centuries.