When I mentioned Aptera, was mainly because it's the only active vehicle in development right now that has that technology. Sonos had a similar concept (I wish they would not run out of money back then) or even Lightyear. The point being is that adding some permanent solar panels (and related...
The slate does have an option to add a tablet as opposed to a phone. So I'm thinking you can add a third party car screen that support the full Carplay experience. They sell them on amazon for like $120.
https://www.amazon.com/dp/B0CQP3CVCD
The idea would be to team up with Aptera to use their tech. Their solar cells are embedded in the body (are very light supposedly) and the MPPT and other electronics are design to be part of the vehicle system. They already have some sort of agreement with Telo and they will offer it as an option.
I'm thinking this could be an option. The current aptera prototype can produce 545W of power from the solar panels in the vehicle body. If the base Slate (with a 52.7 kWh battery and ~150-mile range) had solar panels like the Aptera’s 545W system and sat in full sun for about 6-8 hours a day, it...
I think they sell battery kits for old Leafs that increase the range to more miles than the original battery. So I can imagine this would be possible in the future.
I had a Model Y AWD and a Model 3 RWD and the regen experience is about the same in both from the drivers perspective . Not sure if that answers your question.