Battery question: Can a new battery be old?

Hello. A question that I’ve been busy for a long time – how is it with new batteries you don’t know how long to stand on the shelf? The time when you buy a lead battery the same is just filled with acid are over. Practically all are “maintenance-free” What does the things are filled inside the factory and then stand in the factory and shop. 2 months. 6months. Maybe also 1 year. What happens during this time? They are unloaded and sulfate? Because no store has 1x per month n Charger drann. Looking forward to the answers Gruss, Marco