Expect an AirTag battery to last more than a year
An AirTag works by transmitting a secure Bluetooth signal.
With its low power consumption, an AirTag battery can last over a year under typical usage.
Can You Recharge an AirTag?

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AirTags aretiny coin-sized rig trackersthat don’t have charging ports.
They run on the commonly available CR2032 lithium 3V coin battery, which is not rechargeable.
So, you have to pop it out when it’s exhausted and replace it with a new one.
Alternatively, theItemstab in the Find My app also shows a low battery warning.
You replace the battery by removing the stainless steel cover on the back of an AirTag.
Battery life varies with usage, environmental conditions, the replacement battery manufacturer, and many other factors.
So, your own experience may vary with usage in the real world.
Multiple Apple devices pinging an AirTag to update its location can affect battery life, however.
This feature relies on the Ultra Wideband technology in certain iPhone models to accurately pinpoint your AirTag.
While its highly precise, frequent use can result in quicker battery drainage.
Apple’s advertised battery life is based on a single precision-finding event a day.
Lost Mode
Keep the AirTag out of Lost Mode unless necessary.
This increased activity can drain the battery faster than usual.
Don’t leave your AirTag in your car or in damp or even cold conditions.
Firmware
Apple regularly releases updates for iOS and AirTag firmware.
These updates can optimize battery efficiency, so you should always apply them when they become available.
Batteries gradually lose their capacity when not in use.
Also, store the battery in a cool, dry place.