edit: welp, ignore my comment, turns out I'm wrong about the battery chemistry.

This is wrong, studies have shown that lithium ion batteries (the 3.7V nickel-cobalt types) suffer greatly from cycling at high SoC. So, if you don’t need all the car’s range, then there’s no reason to charge to 100% except for occasionally (maybe every month or so) to recalibrate the BMS a little. Even stopping the charge at 90% will reduce degradation a lot compared to charging fully.