Nest Protect Smoke Alarms or alternatives in 2023

I need to get about 8 smoke alarms so naturally I want them to be smart, I’m happy with battery because they last for years but the Nest battery devices are a bit scarce and I wonder if they’re due to be replaced with a newer version?

Also whether there are alternative HA compatible devices that are worthy of consideration?

The official Nest integration doesn’t support the smoke alarms. There is a HACS integration, but that uses an “undocumented and unofficial” API - so how long that will continue working is anyone’s guess.

Having said that, I’ve had several Nest Protects for six or seven years. The batteries lasted five, so that’s really not an issue. If they’re getting hard to find, that may be something to do with component shortages - a Rasperry Pi is quite hard to get hold of too.

(Assuming you are in the US.)
(Also note that your city/state might require hardwired smoke alarm.)
Anyways I have 2, using your regular smoke alarms, Kiddle or First Alert:

  1. … and then in the same hardwired signal loop install the relay module of your choice (Kidde SM120X or First Alert RM4, depends on which camp you are in), and then use the relay module to trigger a door sensor with terminals (such as ecolink door sensor), or trigger some smart switch of your choice (zooz ZEN51, or Shelly, or DIY your ESPHome…), so that you bring the alarm status to your HA.
  2. There is also audio alarm sensors out there that would “listen” to specific frequencies / sound pattern of your smoke / CO detector, and then use those smart (audio) sensors to bring the alarm status to your HA. This obviously works for either wired or battery smoke alarms.

I thought about using the speakers on some smart alarms for other purposes, or using HA to silence your smart alarms when it is beeping, or use those smoke detectors for temperature sensing… while they are good ideas on paper, in reality they won’t work well, or they won’t work, and become gimmicks… or simply becomes too expensive when you need to replace all of your smoke alarms…

So in the end, would still recommend we keep things simple… what you really need out of your smoke detectors, if you think about it, is really the status & timestamp when the alarm is on.

Hope this helps.
(And yes I’d love to know what other alternatives are.)