Thermal paint is not a new idea, and in fact it is being used in plenty of applications. Just not in cars, because you need a thick coat of gooey paint slathered on to be effective. But Nissan is working on a new kind of automotive thermal paint they call "cool paint." To show it off, they painted some service vans in the new cool paint, and parked them in an airport parking lot. After some time, the vans were nine degrees cooler inside than nearby vehicles with regular paint. That makes a big difference in the load put on an air conditioner, which is especially important in an EV.
This paint is quite different from thermal paints now in use. An effective coat of thermal paint is usually 400 to 800 microns thick, while cool paint need only be 120 microns thick (and it can be sprayed). However, that's still thicker than regular automotive paint, so they are working on it. Read about cool paint and how it worked differently from other thermal paints at The Drive.
(Image credit: Nissan)