Six months ago I started using these in one of my smoke alarms. Since then, I have suffered the dreaded "chirping smoke alarm in the middle of the night while I am trying to sleep" issue THREE times. I.e., I have had to replace/recharge the batteries once every two months!I believe I know the reason now. After charging the batteries, they only get up to 8.29-8.34V. After two months, the battery voltage drops to 8.0V. It's a reasonable rate of discharge, but since it starts at a low voltage to beSee full review