6 month old doesn't nap!!

My 6 month old son will not nap during the day. I've tried everything and he just fights it and will go literally all day without a nap. And I mean NO naps AT ALL. He will fall asleep in the car but it's not always practical to go drive around just to get him to sleep. He sleeps great at night but I feel like the him not taking naps isn't normal and obviously not good for him.. anyone else experience this? Should I be concerned?