Let's see. Capacity of a Tesla battery: 85kWh. Let's say 1m^2 of solar panel can produce 200W in good sunlight, and we'll handwave away all other conversion inefficiencies. Let's say we get 8 hours of good sunlight a day, so in a day 1m^2 of solar panel will give 1.6kWh. So with 54m^2 of solar panel, we can get 1 Tesla charge in a day. Maybe that could work outside of a city where everyone has a big backyard, or can cover the roof in solar panels, or both (I don't think my roof is anywhere near that big at least on its south-facing side, and the back is in shade). Maybe you can buffer it in a vanadium-redox battery so you can actually charge the car overnight. But with the cost and the amount of solar you need if you can only get 100W/m^2 for 4 hours a day, that's going to get real big and hence expensive. And that's when you will really need the vehicle because maybe the weather is too bad for alternatives.

Electric cars in cities are going to go on being powered by a central grid forever, basically, because physics.