72v battery repair

lilgsxr1000

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Joined
Jan 19, 2024
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New York
Attached are a few pics of a slightly disassembled 72v batter for my z motor bike. Testing the regular external battery cables I'm seeing wind 6 volts. Testing the main battery leads without the bms in seeing 65v. I'm guessing the bms is faulty. My question is what caused the battery to get hot in this one spot and if I replace the bms with another one is this battery Savable?
Sorry if it's an easy answer I'm just not familiar with batter operated toys. Fuel powered motors all day long. 72v not so much.
 

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You cant really answer that, not without a schematic of how the battery i s created. Where are the cells, and banks, where are the bridges, are they exposed or encapsulated, shielded,?
What motor are you feeding it with?
What controller are you using ?
What are its true Amp ratings?

Its usually going to be a weak spot in the bridges, or solder joint, exposed wire, or hitting the battery to hard, too long or using regen on something that doesnt properly support it.

I dont know anything about that batter but they are not using legit tape.. what is wrapping around it, it just standard Fiber, or String tape, so there is no shielding there.
You dont want to close up the batter, it has to vent but i find it completely scary that they are wrapping that thing with what looks like box tape across the top and string/fiber tape around the sides....

dispose of it, i wouldn't reuse any batteries out of it, that's my take.

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You cant really answer that, not without a schematic of how the battery i s created. Where are the cells, and banks, where are the bridges, are they exposed or encapsulated, shielded,?
What motor are you feeding it with?
What controller are you using ?
What are its true Amp ratings?

Its usually going to be a weak spot in the bridges, or solder joint, exposed wire, or hitting the battery to hard, too long or using regen on something that doesnt properly support it.

I dont know anything about that batter but they are not using legit tape.. what is wrapping around it, it just standard Fiber, or String tape, so there is no shielding there.
You dont want to close up the batter, it has to vent but i find it completely scary that they are wrapping that thing with what looks like box tape across the top and string/fiber tape around the sides....

dispose of it, i wouldn't reuse any batteries out of it, that's my take.

View attachment 14395



Welcome to the forums! :cool:
 
Your lucky it did not burn your bike to the ground. Or your garage or house. I would dispose of that battery.
 
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