All these years, when I remind clients to change their clocks for Daylight Savings Time, another reminder was for everyone to change the batteries in their smoke alarms. In the newer homes, this meant, A LOT of 9 volt batteries! (now that they go in all bedrooms, hallways, etc.)
I had to buy a new one recently, and discovered Kidde has one now that has a longlife battery, and lasts for TEN YEARS. No chirping at 2 am now!
SO, if any of your smoke alarms are starting to turn a bit yellow, it could be time to change them out anyway. This could be a good time to get these new ones, and never hear another chirping alarms for YEARS.