This is a serious question and not meant to be a joke.
I am getting ready to venture into Z-Wave and home automation. Regarding the Samsung Smartthings Hub Generation 2 - What is the benefit/purpose to going with a battery backup?
In theory the batteries in the gen2 hub are supposed to keep your mesh healthy and allow for local automation to still complete even if the power is out…
That said let’s explore.
The power is out. Most of your devices won’t have backup so they are offline.
Most people don’t have batteries on thier Internet, so you can’t connect to the hub.
Batteries leak. (the Gen 2 hub is notorious for this)
It’s impossible to reset the Zigbee mesh if the batteries are still in the hub. (you cab reset your zigbee mesh by turning all devices off and leaving the hub offline for 20 minutes with no battery)
So all of that to say I have a Gen 2 hub and there’s no batteries in it, and I won’t out batteries in it.
I might put it on a ups with my other network gear… Maybe…
1 Like
The intent was to allow the hub to continue to receive messages from battery-operated sensors during a power outage. For example, one of the founders often talks about a use case where he had a vacation cabin, the power went off, a pipe burst, and he was unaware of the problem.
Theoretically, if the hub was on a battery backup, A battery-powered temperature sensor could report the temperature at freezing and a battery operated valve cut off could be triggered to cut off the water. Theoretically. 
Alternatively, a battery powered leak sensor could report water detected and again the battery operated valve cut off could be triggered to cut off the water.
Noticed that none of this gives the homeowner any notification of what’s going on because all notifications from the smartthings system except for the ADT/smartthings model Require the Internet to send notifications, even push notifications. (That’s in sharp contrast to UL listed security systems, which will have a cellular module for communications.)
Anyway… Even though the homeowner doesn’t get a notification, presumably in this particular scenario some damage might be prevented. 
In practice, however, there were multiple issues. The first, as was mentioned, is that the batteries tended to overheat and leak. Lots of discussion and photographs in the forum about this.
The second is that it’s such a minimal functionality that it really didn’t meet most people’s use cases. They want notification to the human, not just a couple of battery powered devices linked together.
Also note that none of this has to do with the Zwave protocol itself. Or home automation in general. A number of zwave systems “run locally“ or as I mentioned have cellular modules for communications or have longer battery operation, etc.
All of this is specific to the smartthings implementation, which is still primarily cloud-based. And definitely not UL listed as a security system.
So as far as smartthings itself goes, the battery back up isn’t a very popular feature and a lot of people just don’t use it. Which is probably why they dropped it from the newer V3 hub.
3 Likes
Nathan and JD, many thanks for the in depth explanations. You really pointed out the facts in detail. Much, much appreciated.
3 Likes