it's can be very dangerous !!!!!!
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hbpowerwall
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It is good that one one/nothing was really hurt & I respect your time to share as from failure we will as a community improve our methods. Your video isn't working and would really like to see as much information about this as possible! I'm sure together we can learn from this! Thanks for sharing
Korishan
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Ok, a few questions for ya:
1) were you soldering the bms wire to the rocket cell?
2) how much time between soldering the fuse wire to the cell and when the rocketing occurred?
3) why do you not have a video of this whole drama!?!?
seriously though, glad to see you are ok and just needed to change your britches afterwards
Thankfully no one got hurt and the only damage was kept to the pack.
The reason for asking 1 and 2 is because if you were soldering to that cell specifically, then it's possible a piece of solder got between the Pos raised button and the Neg shell. I've done this myself and it doesn't take much to make a short. If it was shortly after connecting the fuse wires, it's possible that you did as I mentioned for 1, but it was a very subtle short and took it a long while to get to rocket stage. I've done this one, too. Well, it didn't get to rocket stage, just got hot and I noticed where the problem was before it became a problem.
I want to make absolutely clear, that if a short occurred between the Pos cap and the Neg shell, NO amount of fusing could possibly keep the cell safe. It was asked why the fuses didn't pop, and this is why I'm asking the above questions. It's also possible that you had a small short, didn't realize it, the bms lead wire came around and bumped the amps up a bit and finished the short in the cell and then thermal runaway took over from there.
1) were you soldering the bms wire to the rocket cell?
2) how much time between soldering the fuse wire to the cell and when the rocketing occurred?
3) why do you not have a video of this whole drama!?!?
seriously though, glad to see you are ok and just needed to change your britches afterwards
Thankfully no one got hurt and the only damage was kept to the pack.The reason for asking 1 and 2 is because if you were soldering to that cell specifically, then it's possible a piece of solder got between the Pos raised button and the Neg shell. I've done this myself and it doesn't take much to make a short. If it was shortly after connecting the fuse wires, it's possible that you did as I mentioned for 1, but it was a very subtle short and took it a long while to get to rocket stage. I've done this one, too. Well, it didn't get to rocket stage, just got hot and I noticed where the problem was before it became a problem.
I want to make absolutely clear, that if a short occurred between the Pos cap and the Neg shell, NO amount of fusing could possibly keep the cell safe. It was asked why the fuses didn't pop, and this is why I'm asking the above questions. It's also possible that you had a small short, didn't realize it, the bms lead wire came around and bumped the amps up a bit and finished the short in the cell and then thermal runaway took over from there.
cristof
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Korishan said:Ok, a few questions for ya:
1) were you soldering the bms wire to the rocket cell?
2) how much time between soldering the fuse wire to the cell and when the rocketing occurred?
3) why do you not have a video of this whole drama!?!?
seriously though, glad to see you are ok and just needed to change your britches afterwards
The reason for asking 1 and 2 is because if you were soldering to that cell specifically, then it's possible a piece of solder got between the Pos raised button and the Neg shell. I've done this myself and it doesn't take much to make a short. If it was shortly after connecting the fuse wires, it's possible that you did as I mentioned for 1, but it was a very subtle short and took it a long while to get to rocket stage. I've done this one, too. Well, it didn't get to rocket stage, just got hot I noticed where the problem was before it became a problem.
I want to make absolutely clear, that if a short occurred between the Pos cap and the Neg shell, NO amount of fusing could possibly keep the cell safe. It was asked why the fuses didn't pop, and this is why I'm asking the above questions. It's also possible that you had a small short, didn't realize it, the bms lead wire came around and bumped the amps up a bit and finished the short in the cell and then thermal runaway took over from there.
No, I was not soldering the bms, it was may be 30 seconde after the video. I was preparing the bms wire, ready to cut them. I supose that one of the cable short the cell just close to CID and minus.
the fuses have been solder yesterday, more than 24 hours, none of the cells was hot when I started to video.
for sure, it's a short after the fuse. I'm guilty !
for the fact section : do we need an extinguisher when soldering cells ? YES or NO ! :-/
Korishan
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Yeah, a little piece of metal between those slits in the Pos end is all it takes.
A fire extinguisher. Good question. However, you'd need to get a chemical rated one as the common house is a CO2 one. That won't stop a lithium based fire.
Drat, "after" the video was shut off. Next time remember to keep shooting until you're done for the day, even if that means 16hrs of video recorded
A fire extinguisher. Good question. However, you'd need to get a chemical rated one as the common house is a CO2 one. That won't stop a lithium based fire.
Drat, "after" the video was shut off. Next time remember to keep shooting until you're done for the day, even if that means 16hrs of video recorded
Korishan said:Yeah, a little piece of metal between those slits in the Pos end is all it takes.
A fire extinguisher. Good question. However, you'd need to get a chemical rated one as the common house is a CO2 one. That won't stop a lithium based fire.
Drat, "after" the video was shut off. Next time remember to keep shooting until you're done for the day, even if that means 16hrs of video recorded
Perhaps we could invest in dashcams, they should be able to do ~6 hours or more on a continuous recording loop depending on the memory card in it. If anything interesting happens, just stop the recording and upload it to YouTube
Korishan
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neurocis said:
I think neurocis might be on to something here. I see some metal pieces on the towel. Is it possible that right before the rocketeer event, you laid the pack down on the towel? This could of allowed a piece of metal to make contact with the Pos/Neg on that one cell and start the shorting.
If that is the case, what a small chance of it happening as you'd have to get that piece exactly right on the cell to get it stuck to the cell.
hbpowerwall
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not2bme said:
You have every right to be worried - you must consider your own safety every time you do anything with these projects ( or any other diy project for that matter)
tremors
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I got 3 MXJOs from a friend at work who uses vapes and I decided to see what's left in his cells after he said they don't have enough power to power his vape.
Opus showed all three as 2800mAh and 50-70mOhms so I decided to run them on a long refresh test and left to go to work only to read this post. LOL
although they were only on a charge, still get the jitters a little. hehe
Opus showed all three as 2800mAh and 50-70mOhms so I decided to run them on a long refresh test and left to go to work only to read this post. LOL
although they were only on a charge, still get the jitters a little. hehe