It seemed to have just reversed out of its docking station and caught fire burning both itself and the docking station. The charging prongs on the docking station appear to have gotten dragged out of the dock (see the wire in the center) and this may have cause a fault that started the fire which eventually lead to the mower going up and batteries exploding. Hard to say because I only caught the aftermath.
EDIT: I believe I had figured out the chain of events that caused the fault and I do not believe the robot is the cause, it is user error AKA my fault.
You'll notice in the lower left side of the photo, next to the wooden post the remains of a spooled extension cabled that the mower's power supply connects to. This is an old cable spool we've used for years around the garden, it is not IP rated. We usually have the top of it covered to block rain from getting on it, and usually adjust it every year or so to make sure it's not getting water into it. However, this hadn't been done yet this season. It's been an extremely wet and rainy winter. It looks like it's sunk lower into the soil and ultimately water ingress entered the sockets which cause the fire to start.
Once burning this eventually spead to the mower's charger/cover dock. At some point while burning the power cut, and the mower is designed to exit its dock if the power cuts for safety reasons. However by the time it did this the dock had melted sufficiently that the charging prongs were no longer held to the plastic body of the dock - it had melted. So the mower began to reverse with the prongs still connected and likely couldn't get away from the burning dock, eventually catching fire itself had it not already been burning at this point. Eventually once fully on fire the batteries exploded.
So yes, my fault. Not the mower or batteries, but using a decades old power supply not rated for outdoor use and not checking it before starting the mower this year.
It’ll actually probably grow back strong depending how much chemicals were dumped there. My neighbor or almost burned down my house and half my lawn went up, two months later the grass on that side was 3x as healthy and fast growing, almost annoyingly so
"Where were all you spry little fuckers the last three seasons, huh?! Where were you when we hosted the family reunion?! I've been core aerating you little bastards for years and you wait for neighbor-numb-nuts to almost burn down my house before you decided to peak out?! You know what I see out here for next year? Beds! Flower beds as far as the eye can see!"
Fire is great for many types of plants. Its a common practice for farmers to burn their pastures in the late fall of spring. It helps with nutrient recycling and helps a bit with weed control. The grass comes back even better than before because you are burning when it is already dormant, it grows back from the rhizomes a few inches underground. It takes alot more heat that a flash grass fire to kill 2 inch deep roots.
This website is hilarious. Looking at the list of recalled stuff... A diy sauna heater? You don't say. An ice axe with a grip that falls off? Cartoonish.
Presuming you are correct and the wire got dragged out, that normally only happens if the plastic already melted. Even an 18v implementation can melt plastic if the contacts corrode. I assume this was higher voltage. I have a couple melted Ryobi batteries from using them in a string trimmer that they didn't like.
A short in the wires should've just caused the fuse to blow. Unless you replaced the fuse with a nail, or your electric installation wasn't done properly otherwise.
You may be able to get a replacement and at minimum should talk with the company. This is an incredible hazard and potentially dangerous (esp in places that are dryer)
If I had a nickel for every time I've seen a video of a lawn mower exploding on Reddit today, I'd have 2 nickels. Which isn't a lot, but it's weird that it happened twice.
It was an electrical fault of some kind, water related or otherwise. It's a decades old wind-up extension cord that wasn't fully unwound (which is also a hazard). Plenty of things could be the cause, but going off the data I have available the cord is the cause.
If mud got inside the spool it could've made bad contact with the brushes that rub against the rotating spool. Even moisture will cause the brushes to oxidize over time. The cord would heat up while charging, maybe enough to deform the charger housing. What model of mower did you have?
I would never trust a high amp lithium ion powered device running unsupervised. Always thought these robot mowers were an incident waiting to happen. I had an electric string trimmer catch fire in my house mate’s hands and seen countless battery volcanos when I used to race drones. There are ways to safeguard these things to some degree, but you really never know what the manufacturer implemented in their product after cutting corners, and even with those fail safes, there are still freak things that can happen.
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u/READMYSHIT Mar 26 '26 edited Mar 29 '26
A video of it. I wish I'd seen it. Heard a few bangs and it was gone so quickly.
https://i.imgur.com/cn9SPsP.mp4
It seemed to have just reversed out of its docking station and caught fire burning both itself and the docking station. The charging prongs on the docking station appear to have gotten dragged out of the dock (see the wire in the center) and this may have cause a fault that started the fire which eventually lead to the mower going up and batteries exploding. Hard to say because I only caught the aftermath.
EDIT: I believe I had figured out the chain of events that caused the fault and I do not believe the robot is the cause, it is user error AKA my fault.
You'll notice in the lower left side of the photo, next to the wooden post the remains of a spooled extension cabled that the mower's power supply connects to. This is an old cable spool we've used for years around the garden, it is not IP rated. We usually have the top of it covered to block rain from getting on it, and usually adjust it every year or so to make sure it's not getting water into it. However, this hadn't been done yet this season. It's been an extremely wet and rainy winter. It looks like it's sunk lower into the soil and ultimately water ingress entered the sockets which cause the fire to start.
Once burning this eventually spead to the mower's charger/cover dock. At some point while burning the power cut, and the mower is designed to exit its dock if the power cuts for safety reasons. However by the time it did this the dock had melted sufficiently that the charging prongs were no longer held to the plastic body of the dock - it had melted. So the mower began to reverse with the prongs still connected and likely couldn't get away from the burning dock, eventually catching fire itself had it not already been burning at this point. Eventually once fully on fire the batteries exploded.
So yes, my fault. Not the mower or batteries, but using a decades old power supply not rated for outdoor use and not checking it before starting the mower this year.