The StagesPower meter calculates an estimated battery life remaining which can be checked using the StagesPower app or certain head units that enable this feature. Here's where to look:
Checking battery status in the StagesPower app
Checking battery status on your Garmin head unit
Checking battery status in the StagesPower app

If you have the StagesPower app installed on your smart phone or tablet, you can easily check the status of your power meter's battery. The StagesPower app displays an estimated battery life in the lower right corner of the app's home screen. The battery indicator may take 5-10 seconds to show up after a connection is made through the app, but once it loads will give you an easy visual reminder on how much battery life you should expect. This battery indicator will display green from the time the battery is new until it starts to run low, then changes to yellow when the battery has only 15-20%, and red at 5% or less power remaining. Keep in mind that battery life is being estimated and that expected remaining time can vary slightly.
Related links:
Stages Power - Android App Link
Checking battery status on your Garmin head unit
On some Garmin models, you are able to check your battery status within your head unit. The power meter does only send battery updates every few minutes, so it may be helpful to check after the power meter has been on and connected to the Garmin for several minutes, otherwise the Garmin may report that sensor information is unavailable since it has not received the information yet.
Edge 500/800
On screen prompt "Power Meter Battery Low" will pop up at less than 5% of battery life remaining.
Edge 510/810
On screen prompt "Power Meter Battery Low" will pop up at less than 5% of battery life remaining.
Battery Status visible from Settings (Tools Icon) > Bike Profiles > Bike 1 (or applicable bike profile) > Power meter (Barbell Icon > Sensor Details > About Sensor. Please allow 5-10 seconds for the additional sensor details to load.
Edge 520/820/1000
On screen prompt "Power Meter Battery Low" will pop up at less than 5% of battery life remaining.
Battery status visible in Settings (Tools Icon) > Sensors > Select the ANT+ ID of your power meter > Sensor Details > Battery Status
Forerunner 910xt
On screen prompt "Power Meter Battery Low" will pop up at less than 5% of battery life remaining.
Forerunner 920xt
On screen prompt "Power Meter Battery Low" will pop up at less than 5% of battery life remaining.
Battery status visible under Menu > Settings > Sensors & Accessories > PWR - [ANT+ ID] > About > Battery
If you are unable to find the battery indicator or need help otherwise, please open up a support ticket with Stages Cycling or Stages Cycling Europe or visit your nearest Stages Cycling dealer for assistance.
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