It's not as much about the coating as it is the casing of the batteries. The Panasonic, that the AirTag comes with, has a thinner black separation between the positive and negative at the edge of the battery. The profile of the Duracell, and and some others, is slightly different. I've tried Duracell and CVS's house brand, that has no coating, and neither worked. The AirTag makes the noise when the battery is inserted, however; when the lid is put on it looses connection. There is a video on Youtube about it. So far I have not found another brand, other than Panasonic, that works in the AirTag. If someone else finds out what other brands will work, can you please let us know. Thanks.