Can I leave my AirPods outside of the case overnight if they’re fully charged and expect them to still be fully charged in the morning?

My question is can I leave my AirPods outside of the case overnight if they’re fully charged and expect them to still be fully charged in the morning.. or do they always have to be inside the AirPod case if I’m not using them? Can they be overcharged?

[Re-Titled by Host]