As we would expect IoT is going to be getting more and more in our everyday world.
That is interesting. So, to get the 5 years life I’m assuming everything is in deep sleep until it detects a sounds. I’m curious about how you configure it and what sort of WiFi solution they’re using. Hopefully someone will do a teardown. I’m tempted to get one just so I only have to change my batteries every 5 years. Heck, they’d probably make a lot more money if they’d just sell a five year battery without any of the intelligence for half the price. Does such a thing already exist?
EDIT: a quick search revealed that there are 9V LiPo batteries available for about half the price. I may have to pursue those further for use in our smoke detectors.
It would be nice if the device could communicate over the wifi in the battery instead of having to have it’s own.
@ Mr. John Smith - Yeah. That would be awesome! Imagine the fun hacking your neighbor’s smoke alarms to have them all go off at 3AM 
I don’t understand your suggestion.
While I think WiFi in the battery is clever, ultimately the WiFi should be in the device itself (because the device knows what’s going on much better than the battery can guess at it). You should be replacing your smoke detectors every 10 years anyway, so by the time the next cycle comes around, WiFi will probably be standard.
Seems like it’d be a pretty trivial hack to drop an ESP8266 in a smoke alarm and hook up one of the GPIO to the piezo buzzer.
@ ianlee74: Here’s a 9v lithium warranted to last 10 years, for $9 shipped: Amazon.com
Home Depot sells wirelessly-linked combo smoke/fire/co2 detectors for $43 each in 3-packs (works with the Wink hub, whatever that is…): http://www.homedepot.com/p/Kidde-2-in-1-Battery-Operated-Wireless-Combination-Fire-Smoke-and-Carbon-Monoxide-Alarm-with-Voice-3-Pack-21010625/205133645
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I found it interesting that it handles onboarding through a smartphone microphone : [url]http://www.makeuseof.com/tag/smoke-detector-battle-roost-smart-battery-vs-nest-protect/[/url]
I also really doubt the five-year claim, unless that’s for battery backup of a hard-wired detector. Typical draw for non-hardwired units seems to be 50 uAh, which is 438 mAh total over the course of a year. Considering that the pure lipo 9V referenced above is 500mAh, unless they figured how to vram 2500mAh into that case, the five year figure is for the much lower current draw encountered with hardwired detectors.
Amazon reviews of the thing are decidedly mixed.
@ godefroi - That warranty again appears to only be for battery backup - not primary supply. The Amazon comments seem to back that up.
Great links though, esp the home depot one. It makes infinitely more sense (to me) to have the smarts in the sensor. Those devices may actually be Zigbee though since the wink hub is a Zigbee to wifi bridge. The wink hub requires a separate wifi access point in order to operate.
Actually, there’s an easier way. Me and a partner built this at a hackathon a couple years back. Nearly all smoke detectors today have a wire that interconnects all the alarms in the house. If you want to know if any alarm in the house is going off all you have to do is watch that wire for 9V. Additionally, if you want to sound off all the alarms in the house you can just apply 9V to the line (takes about 5 seconds before it starts). We built a remote fire detector for 3D printers (or any other thing that could be fire prone). It had a fire sensor at the device and that was connected to a base station that tapped into the interconnect line using NRF24L01+ radios. So, if a fire was detected at the printer then it would instantly sound the alarms rather than having to wait for smoke to fill the room. It worked rather well.
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I still think the best tech for a smoke alarm is just a voice pattern recognition that would let you yell “I’m just cooking, dammit!” at it, and have it turn off.
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