If you're using your Airpods with an Android device, you should check out the AndroPods app, it allows you to see your Airpods' charge levels from the notification panel and also via
TicPods 2 Pro: Still a solid Android alternative to Airpods - 9to5Google
Video: How To Use AirPods With Android Phones: Pairing, Check Battery Levels, And More | Gadgets 360
Zo werken Apple AirPods op Android-toestellen via bluetooth