At 00h50 this morning I got an alert on my phone that one of the garage doors has been standing open. It’s quite an aggressive alert, so I get this after 3 min.
The battery caught fire. I think it’s either that something went wrong with the charging circuit of the controller board, or that the plates in the lead acid battery (still the original from a few years ago) have failed, causing a dangerous mixture of chemicals.
Either way, I think, when some wires melted, it basically acted as a momentary push button, so it triggered the door to open with its last breath – and hence I got the alert.
I installed a smoke detector in the kitchen recently. I’ll now be installing one in the garage too (a separate outbuilding). It’s not part of my country’s domestic building codes, so it’s up to oneself to do these things.
I happened to have installed fire extinguishers recently too, specifically one for putting out Lithium fires (our solar backup power system). Luckily, I didn’t need to use either last night.
I feel immensely lucky today.
EDIT:
I had a team here to assess my damage and they confirmed that my garage door motors can run without batteries, so I’m not going to replace the one that went up in flames and I will remove the other one that hasn’t (yet). It seems like the cause of the problem was the controller board. I have a solar backup power system, so I don’t need them, and there’s always manual control to override anything.
What kind of controller board did you use? Was it esp32?
Did you have a temperature sensor enabled on it to monitor device temperature?
Sorry for asking this but people recently started reporting fires with their smart devices.
Something should be done, some strategy should be implemented to prevent this from happening.
I had an office full of acid fumes from a failed sealed lead acid battery a month ago. It was on a good quality charger but those batteries just seem fail occasionally. They do give you a fair warning with their puffed up sate but unless you’re looking for it, easy to miss.
Not as bad as lithium, still can be quite catastrophic.
Luckily, except for my sensor picking up the open door, this was unrelated to any of my IoT devices. This was the garage door motor with its built-in controller board and attached battery. My only connection there are two wires to trigger a momentary button press (to open and close), but that’s connected to a dry contact relay.
There’s no onboard temperature sensor for that out-of-the-box system.
One thing is that people should be careful when building their own devices (myself with an electrical and electronic background included).
Well talking about this on other thread, the only thing that cross my mind is to have exposed temperature sensor on every device.
Some devices have this no matter if they are battery powered or not like this motion sensor.
Monitoring devices temperature can be considered as preventive measure. It could be fairly easily to set up in home assistant.
As I understand it will take some time for devices to reach high temperature and start a fire.
I’m not sure it this is the case but maybe exposed devices temperature should be a part of ie. zigbee certification or any other certification.
Lesson learned for me: There are more things to deduce from sensors that one think sometimes.
I had sort of a similar event:
I managed to save my pool from completely emptying in the underground (due to a sudden leakage in a water pipe) by having once made an automation in HA that would alert me if the current of the pool pump was diverging to much/too often from a known, standard value.
This automation was triggered by the pump having to manage with altered water flow and then having irregular current values. I never expected that this automation would have been THAT useful in THAT particular case.
By the time the automation triggered and I understood what was happening I had already lost 1/3rd of the water. HA saved the rest sort to say, which is a substantial amount of money.
So it’s not just the sensors, it’s also the automation and alerts that you create on top of them.
Now I’m thinking more about what I could get from each sensor value and if that’s worth building an automation and alert. I have now 10 of those automations in place, but it’s nothing really. More things could be envisaged.
None of my alerts are about temperature raise, so your story is adding a new plane of consideration in my mind, thanks for sharing!
Wow this is the second battery I’ve seen this week like that. Glad you were able to get the notice.
In all seriousness, the other swollen flamed battery did make me check all of mine yesterday and sure enough one of the cells in my desktop’s ups is swollen. (I’d been slapping silence on the alarm for a few weeks telling me the battery was failing - I’d get around to it. Meh no big deal right?)
Well it’s off now. And the ups is now in the garage and I now have a bunch of 9ah batteries on the way and im replacing ups batteries this weekend.
My first thought when I saw the photo was a sigh of relief that it was “just” a flooded lead-acid (FLA) battery. The story could have had a very different ending if it were a Lithium-based battery chemistry.
Yes, I’ve seen FLA’s boil dry and catch fire. I also saw one explode once. But the failure modes are quite different depending on the battery chemistry. For all their limitations, using a FLA battery here was probably the right call. And understanding these different failure modes is important for being prepared.
To lighten things up a bit, I’m always finding unexpected ways to use my HA data. For example, I know when other housemates get up in the morning because the sensors on my hot and cold water pipes show a change when someone runs the water. On the down side, I once learned that a house guest doesn’t wash his hands after using the bathroom.
Indeed. I’m actually considering replacing some of the small lithiums I installed in various places again with lead acid since I have a full solar backup power installation now. I got those for longevity and deeper discharging, but I don’t need that anymore.
I use Yolink which requires a hub as it uses more reliable and longer distance Lora, and I just recently installed 4 smoke detectors. Yolink has a pretty good 24/7 integration with HA and it also offers a third party 24/7 monitoring system (that is the only reason why I went with the cloud inn this one case). My wife burnt a potato io the micropwave (cooked it twice by mistake so it really had flames!) and the fire depoartment weas here within 5 minutes. They call your cell phones first but we were too tied up to even notice or answer. Kudos to them - and you should consider the same!
In thoroughly reading the reading the smoke detector instructions, they mentioned that in a space like a garage you shouold also consider a smoke detector as well or instead of a smoke detector (I forgot the rreason but it made alot of sense - maybe the garage gets hot in the summer?). And - I would get rid of that battery and pay an exlectician to run a line out there to your garage (or have the battery outside away from the structure)?
Also, if you use something like Yolink and have any kind of complicated routing rules on your home network (like I do with 10 randomly rotating VPNs running on the router as client for everything on the network to be protected, consider a separate vlan with a direct internet connection (*which is what I did) or even a separate dedicated router with wide open internet access that would be rock solid with no issues ever - so that the yolink hub always has uninterrupted access to the web so there are no issues in that regard (expecially if it is being used for something as important as a burglar alarm or smoke detectors).
*Sorry but I digress below - For a long time I had no separate vlans but when I finally put my yolink hub on it’s own for the purpose mentioned above, one by one I put my IOT devices onto that same vlan which is best practice - purposely only 2.4ghz with no von or DNS ad blocking etc. I also have all of thinghs that are exposed to the internet foir firmware updates etc. always have 30 digit unique passwords. FOr my HA to reach those items with no issue, as I have HE Suprervsed running on a RPIU4 w/8Gigs of RAM - with a simple instruction you can have the RPI running with two ethernet interfaces so it is on both networks and can still hear everything. That might not actually be best practice. Anyway, I also noticed then if you use a third party app on your call phone (such as the Shelly app) it cannot easily see those other devices since my cell is on a different vlan than the IOT. Still need to work that one out however…
Just had a team here to assess my damage and they confirmed my garage motors can run without batteries, so I’m not going to replace the one that went up in flames and I will remove the other one that hasn’t (yet). It seems like the cause of the problem was the controller board.
My UPS stopped running on battery. Found severally decayed batteries (3yrs old, puffy and leaking). I’m making it a scheduled task to replace these. I’m thinking test function once a year and replace after 2yr
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Wondering how you got a pic with the flames? Did you actually take a picture before dealing with the dangerous fire in garage? I think I would have done the same. Actually, I’m sure I would have done the same.
I think I would have done the same. Actually, I’m sure I would have done the same.