ecobee SmartSensor uses a 3-volt CR-2477 battery that can be purchased here:
Change the battery
Replacing the SmartSensor battery involves gently prying off the battery cover, removing the dead battery, and replacing it with a new battery. Ensure that the positive side is facing up.
If you're having trouble removing the back cap or removing the battery, try using a small, thin tool such as a pen, plastic card, or a screwdriver to gently coax the cover off and lift the battery out.
Note: SmartSensor is incompatible with CR-2477N batteries.
Learn more about SmartSensor
Click here to learn more.
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