Motion Sensor Battery Life
How long do the batteries last?
Battery life can vary depending on the brand and the level of activity in the area the motion sensor protects. Most batteries will last anywhere from 3 to 12 months. In a high traffic area, changing the batteries every 3 to 4 months is a good idea. If little movement occurs, then they will not need to be changed as often. One recommendation is to replace them during Daylight Savings just as you do a smoke detector.
Remember, whenever you remove the batteries, it will reset a home automation motion sensor to A1, and a security motion sensor needs to be re-initialized.