[jeanjq]

I wonder what battery life is like on this? A typical smoke alarm battery can last years but this appears to have a lot of functions and WiFi and a light.

BTW Why do smoke alarm batteries die at night? Because temperature drops and a weak battery's voltage output drops with temperature.

[uptown]

According to the site - for the battery-powered version:

"6 AA Energizer Ultimate Lithium batteries Long-life batteries designed for multi-year operation"

and for the wired version:

"3 AA Energizer Ultimate Lithium backup batteries Long-life backup batteries designed for multi-year operation"

I suppose it depends how much you use its features like lighting-up your hallway, but that's more-than reasonable in my opinion.

[raverbashing]

I really wished they had innovated in that sense

For example with a wireless energy transmitter (it doesn't need to be too powerful).

Or "solar powered" with a good set of (rechargeable) batteries.

[robmcm]

So in theory during a fire they should heat up and start working again! Phew...

[wikwocket]

Although battery life is certainly important for a smoke/CO detector, as many people will never change the batteries, around here the fire departments recommend putting in fresh batteries every time you change the clocks for daylight savings time.

Maybe they are in league with battery manufacturers, but I feel safer, and have plenty of extra mostly-charged batteries for remotes and video game controllers!

[macleanjr]

In the Wired article[1], there is a graphic that states battery life is seven years, and the batteries can be replaced for $10-$15 off the shelf.

[1] http://www.wired.com/business/2013/10/nest-smoke-detector/al...

[cjrp]

"Multiple years" on 6xAA (or there's a wired version with 3xAA as back up) according to http://www.theverge.com/2013/10/8/4790896/nest-protect-smoke...

[hemancuso]

http://support.nest.com/article/What-is-the-difference-betwe...

Looks like a couple of years with 6 AA batteries.