Today I replaced the battery in my smoke detector.

https://lemmy.world/post/42680041

Today I replaced the battery in my smoke detector. - Lemmy.World

I even used a ladder.

Do they even have batteries anymore, I thought you were supposed to replace them after 10 years and they all have built in batteries now
Depends on how dusty the room is. Every time a bit of dust gets in there, it has to power up and check whether it reaches the threshold. All that powering up can drop a supposedly 10 year battery down to just a couple of years in a dusty environment