It caps out at 100%, so of course it's not going to be exponential growth. It is likely to be a logistic curve though, and we are still in the roughly exponential leftmost portion of it. Once there's mid-double-digit market penetration it's going to slow down a lot to roughly linear, then eventually, asymptotic.

Yes, that's more what I'm picturing. That asymptotic phase makes 5-8 years seem unlikely unless a legal obstacle is introduced.

several battery breakthroughs that will dump the cost way bellow the holy grail of car batteries of $100/kwh that makes them on pair with ICE cars. Some estimates predict that they will go way bellow $80 in 2021-22, Means end of 2022 beginning of 2023 will be flooded with even cheaper comparing to Model 3 cars with better quality batteries. Good quality $25-30k electric car will be a new reality. Those segments attack bestsellers like Toyota Camry etc... I'm pretty sure the price war will push them even lower within 1-2 years. Means full line of EV's from very cheap to luxury by 2024-25 on a scale from multiple companies. As a result we will have cars on the market that cost the same, perform better, and cheaper in a lifetime from service and fuel perspective. Millennials and GenZ also very eco-friendly, which means younger people are eager to buy EV's. The only delay could be new battery terra-factories rollout lag. That might give an extra 1-3 years lifetime for ICE. After that the traditional car market will be shaking as never before.

great read on this topic - https://about.bnef.com/blog/behind-scenes-take-lithium-ion-b.... As usual, more nuanced than I naively thought. "Put simply, something that looks like a future breakthrough today might end up simply being another point on the curve, by the time it is developed and engineered into a viable product and brought to market in a decade’s time."

It has held at exponential growth for ~5 years. It can't be exponential, it has to be a sigmoid, but I'd expect similar growth rates for a few years more.