Another lipo fire - house damaged

[RallySTX]

Glad the damage was minimal, that's what stopped me from continuing my build. I just can't risk a fire here. Stupidest move for me was selling the Spoiler, but I digress. Better luck next time.

 

[Rix]

"Hyena"]OK, so here's yet another example of lipo badness.
I was super lucky in this case, as below.

To take it from the top, someone sold a guy a conversion kit and large 18S 30ah lipo pack. The seller apparently bought a kit or parts from me many years ago and has tried to copy the battery construction with a whole bunch of hobbyking lipo. He then sold it for an absolute fortune to a noob, using my name, saying it was one of my kits. Not cool.

This is how I received the battery from the new owner. Not surprisingly, he's not sure about how to use or charge it, with the supplied 25v charger,3 celllogs and a battery medic...


This was made by a guy in Perth named David. David, if you're reading this you're an asshat and a jerk. But I digress
So what he's done is string all the discharge leads together in series and parallel, with the 2 bullets being the main 18S ~75v output.
Back in the day I used to parallel charge my lipo packs, so used a 6 pin anderson block which essentially isolated the sub packs when disconnected and put the packs into series for discharge and parallel charged at 6S voltage. This guy has partially copied that, with a 25v charger but hard wired all the cells into series. Thankfully the new owner didnt try to connect the charger. And lets not begin to think about how the guy was supposed to check, monitor and maintain balance with one BMS for all those individual, unparalleled balance taps!

OK so that's the back story, and in order for the new owner to try and salvage something from this pack I offered to re-wire it and fit a BMS so it was atleast somewhat save and plug and play friendly for him.

When I started to disassemble the rats nest of wiring though I discovered that a number of the cells were in bad shape, 6 of the packs were significantly swollen and reading ~4.25v /cell. The rest of the cells read betwen 3.8 and 3.5v.


Oh yeah, the fire.
So I put the bad cells in a biscuit tin and put them outside my garage until I could dispose of them properly. For long term storage they should have been in something more sturdy but that's all I had on hand. They were sitting a few inches from my closed roller door and about 3 feet from the back of my car.

This sucks Jay, but I am glad it wasn't worse. I don't know if someone else brought this up as I didn't have time to read the entire comments, but 4.25 volts on bloated cells :? No shit that's asking for trouble. I think that's what did it. Who knows what David aka Homey the Clown did when he built the pack with the funky 25v charging set up. Add to that that the packs were probably over discharged, and obviously over charged. Hell, I am surprised the packs didn't catch on fire while in transit to you. It was just dumb luck the pack thermally broke down on your watch. I am betting if those packs were sitting at say 3.9 volts, you wouldn't have had the fire.

 

[MrDude_1]

on the very bright side of all this.... You and your house are ok.. but if the guy that had this pack tried anything, the entire pack would have probably destroyed his house.