No i think the battery case only uses battery if you take out the air pods and use them and then put them back in. i don't think it uses any battery if the air pods stay in the case.Say you don't use them for 3-4 days then the case battery will be down to maybe 30% but the Airpods will still be full?
There really should be a way to stop all battery depletion when nothing is being used/charged.
my case has dropped only 15% all day.