CMF Buds 2a is the first TWS I've owned, so I don't know if this is the standard behavior for all products like this. When the buds are in the case they will always charge up to 100 and stay there until the case battery runs out.
This is great for heavy users because the buds are always ready to go for hours, however I'm worried about the battery life impact. Everyone says keeping a lithium battery above 90 for too extensively damages it
Perhaps they can introduce a charge limit like what we have on our phones? I wouldn't mind a 70% limit as I will never use it enough to run out