i soldered my first battery pack straight to cell (160+ joints!) with no issues. If you check the datasheets for these cells, they test them to pretty extreme temperatures. I doubt soldering directly to the cell would cause any issues.
Also, I’ve shorted balance leads before and since the wire is thin, it should fuse out and disintegrate. Even my 10mm nickel strip disintegrated when i shorted it once.
It’ll likely be impossible to tell exactly what caused this fire, but should be a good reminder to be as safe as possible when constructing these lithium packs and insulate, insulate, insulate!
ouch, sorry for the loss. I wanted to make a flexy Trampa board as well. Maybe the flex is an issue? Was there room between the wires and bottom of the deck? Maybe the compression, vibration and rubbing caused the short.
I used those isolators in all other builds and never caused any issues, I remove the battery enclosure several times prior this incident, at least 20 times, the insultators, wires connecting the packs, nickel strips were always perfect, no pack was bad or unbalanced ever, this was a pretty good looking job.
I wouldn’t like to start causing doubts to all innocent components, I’m pretty sure the issue was wires vaporizing and igniting the fire, later they melted the silicone isolation and shorted the batteries.
For me, no more BMSs on flexible packs or maybe use conformal coating on the balance wires
I had a short on balance lead and it caught fire so definitely a possibility. I wonder if there is something we can spray to make things less flammable inside a enclosure
I use a 3" x 3" aluminum square fence post and slice it so it works as a tray for the batteries. I line the inside of the tray with peel and stick vinyl hot glue the batteries and heatshirk the while thing.
Road debris can easily penetrate the batteries if there isnst a hardshell. Here you can see how something tried to penetrate the aluminum plate.
Hey man, sorry about your board. I know exactly how you feel, your scene looks identical to what happened to me: https://www.electric-skateboard.builders/t/some-fun-video-of-my-longboard-exploding/26120. It really sucks when something like this happens, but i hope it inspires you to make your next build even better. Your trucks and motors are probably still salvageable, it’s a good conversation starter for me when I tell people that my motors survived a fire.
@Eboosted
I’m working my on a pcb to assemble battery packs, will share once is tested. With this all connections will be done on the pcb and the pcb spot welded to the battery, so no direct wires on the batteries.
