DIY- Battery Backup Hubitat- under TEN bucks-NO soldering

Using hubitat as my security system, I need to be sure it would turn on my sirens if the power was out, so on a hunt I went. Came up with 3 components for a quick cheap battery backup. I just let my hub run for 5 hours on this battery, with minimal interaction with the Hub UI, and it likely could have gone longer, but didn't want to risk it unnecessarily. YMMV

Holder/Charger/Power to Hub

Usb to Hubitat Wire 5.5mm x 2.1mm

add a quality 18650 battery (~4 dollars) Panasonic/Sanyo 3500 mAh & (a phone charger you have laying around(free!)


Wow, that is very cool. And all bits available in Asia so cheap. Woop woop! This is a project I will definitely try! So you just put the battery in, plug a 5v phone charger into the side, and then use the USB at the end to power the device using one of the cables, right? And the thing will work nicely when powered but the battery takes over if the power gets cut. Very cool.

Any case options you've found?

Do you know what the run time is on this?

I am tempted to buy a setup, if I do I will design a case to 3D print.


He stated 5 hours and it was still running.

Would like a copy of your design if do make it. Will try to source a printer somewhere in Asia.

Cool idea. I'll be a little contrarian here... I've become much more conservative about the potential for things that could burn the house down. Generic Li-ion charge controllers, even though they use the same off the shelf parts as anyone else, does scare me a bit. Can anyone do an AvE- or bigclivedotcom-style breakdown of this? Does it have any fused or thermal protection?

I have my network and most smart home gear on a UPS, but wouldn't mind putting something like Hubitat on its own, longer-lasting backup.

You can get a 10000mAh Power Bank for under $20 on Amazon. Or a 28000mAh one for under $30. I believe these could be run permanently installed like a UPS, charged by a wall wart/phone charger cube, and powering the HE hub from its USB outlets.

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Not all battery backups do charge and power at the same time, that's the challenge. Most times charging the backup will cut the output.
I'd much rather trust a brand name cell, like Panasonic.


Check YouTube, some guy did a full evaluation of this device, both over current and over voltage protection are included. I got about 5 hours and certain it could have gone longer, but I got worried and restored power to the device. I'm going to take a fresh backup and then run it till it dies. The hub is very power frugal. I did minimize my interaction with the hub interface while testing battery life, as I'll sure would be appropriate during a power outage. I doubt I'd be messing with my hub interface during a power outage.


I just got the guts to let it run 6.5 hours. Set HSM to away, was gone for about 3 hours. Came home and fiddled with some lights, checked logs, all looked good. Troubleshooting a zooz powerstrip required a z-wave repair, which completed, all while on battery. When I started worrying, a total of 6.5 hours later I restored power.
YMMV based on apps, activities plugins etc. I have 128 devices


If any of you guys is based in EU there is ready made UPS available on eBay.

What's the price? I'm particularly happy with my setup as the nearest commercial product is 35-40 US dollars. however you have no control over the cell quality with the commercial setup and once the battery dies, it's likely not repairable.

There are 18650 cells inside. The manufacturer doesn't make it easy to replace the cells but there always are ways to do it :grin:

Battery holder/charger Device is now on sale at banggood for $2.17 USD

This is awesome. I have just ordered the parts. Also I had a look around and I found a 3d printable case here - 18650 battery + wemos 18650 battery shield v3 + 3d printing box by EunchanPark - Thingiverse

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I just got the guts to let it run 6.5 hours. Set HSM to away, was gone for about 3 hours.
YMMV based on apps, activities plugins etc. I have 128 devices

Impressive, but I don't completely understand the use-case here.

Is your interest in

  1. protecting the HE itself from corruption due to an unclean shutdown (ie., surviving a brief power outage (<1min - 15min))
  2. keeping the HE up during a long outage
  3. or something else?

I can't see any benefit to a backup battery other than scenario #1 -- which is a substantial convenience.

In any other case, almost all the devices would be unreachable (even the battery-powered devices would be off the zigbee/zwave network if the powered repeaters are down and the network meshes haven't repaired, right), the external alert system (ie., internet) would be down (unless you've got a battery-power cellular backup, and the local cell system isn't overloaded with people calling each other to ask if the power is out), the home LAN would probably be down (unless there's a UPS on critical switches & routers), etc.

However, it's still a cool project, and something I may well through together.

Both 1 and 2. All my battery sirens and sensors need no repeater to reach my centrally located hub. So it's a backup for security. I obviously won't be notified if power is out, but my neighbors are certain you call the cops, probably twice!
5 battery sirens all over 100db will tell the lowlifes they're not welcome.

And #4, because I can and #5 it was fun

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The problem here is when the power bank looses line power, it goes dead for a couple of seconds. Thus causing the HE to reboot.

I tried using a power bank and it failed the line power disconnect test.

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Yes as most powerbanks would, since they can't charge and discharge simultaneously. There are only a select few that can do this and I have no idea which ones.
The model I posted above is made just for this purpose for Arduino or other device platforms.
I have tested my cheapo backup and it has not rebooted my Hubitat upon power loss.
I now have 2 and just ordered 3 more for my xbees.

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I went ahead and ordered on off of eBay a little bit ago. Also found the 3D print Thingaverse case file and I will be 3D printing that this week.
Thanks !

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