[Altavia]

Originally Posted by retiredguy123

Just to clarify, the current code requires smoke detectors to be hardwired into the house. But, if the house was built before the code requirement, then you can install 10-year smoke detectors that have sealed, non-removable batteries (your second link). You replace the detector, not just the battery. Your first link to the battery would not meet this requirement, because it is for a smoke detector that uses removable batteries. Also, some experts recommend not using lithium batteries for smoke detectors because, even though they may last longer in use, when they fail, they fail very rapidly. Also, the lithium battery may have a 10-year shelf life, but most alkaline batteries claim to have a 15 to 20 year shelf life. I use alkaline batteries for smoke detectors.

The CPSC determined the cause for lithium failures the was a high internal resistance in the batterys tested and subsequently changed the recommendation once root cause was corrected. But I would only use batteries certified by the manufacturer for smoke alarms.

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