Comment by moogly

I really don't get this meme. AAA batteries are terrible for most (not all) sensors because it makes the sensors enormous. Like the newer door/window contact sensors. Coin cells aren't expensive, which people often claim. Maybe if you buy them 1 by 1 at the grocery store. If you get the right sensors, battery life can be 2-3 years.

Like, IKEA's Zigbee water leak sensor (BADRING?) with 2 AAAs (1.2V; they don't like 1.5V) has a battery life of 9-12 months. My Aqara water leak sensors (CR2032) have been going strong for at least 3 years. They predate me starting to track it with Battery Notes and that has to be 3 years ago (and yeah I test their functionality every 6 months or so).