You have to look at the width perpendicular to the direction the current will actually travel. That looks like it’s more like 150 mm in what I would call width, while what I would call the length is what you’re saying is 31.75 mm. That should be good for something like 300 amps, which should be plenty.
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0.2mm pure nickel is good for about 20-25 amps for every 10mm.
The current will be travelleing as below:
Accordingly, the width you wanna measure is:
Assuming these are 21700s it looks to be about 100mm or so which would do ~200 amps easily. Wtv the measurement, use the chart above to calculate amperage.
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Thank you guys, i knew something was off, misunderstood the width vs length. Thanks again
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Is this after charging or after disscharging? If after charging and it has charged too fast, yes, something is wrong. Bad cell or bad weld most likely.
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While charging…
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Rip that group. Check all welds would be my first step.
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Thx, I guess I won’t be riding today…
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Im guessing loose nickel
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Hey guys. Just wanted to link this in case anyone was interested.
It’s for sale: $350 plus shipping
I usually just add as many welds to each cell that I can unless there’s very obviously a set of welds that’s loose. More efficient imo and if one set of welds is weak, there are often others in the group.
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This could just be a BMS issue. I’m fighting with an 18S BMS on a specific setup doing this same thing to me which charging.
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Yeah i just had the same thing with a brand new 10s10p with an LLT wired for discharge. I just ripped the bms and suspect group and replaced them both
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LLTs have been spotless for me so far, I really hope it stays that way.
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Yeah i really don’t know what the problem was, but was easier just to replace the potential problems rather than troubleshoot
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I was out for a ride to see what it would do under load and it sagged from 47.5V to 42V triggered the mismatch alarm (0.23) on my metr pro. BMS is wired for charge only. I’m also using battery modules so it could be a loose bus bar or something. I’m going get a kweld and use nickel. Question… can I use my cells from this battery to rebuild using nickel providing the cells are good I plan to check the IR of each cell before doing so.
Shouldn’t be an issue as long as you leave the cells in the same groups. Additionally, the IR measurements should be taken w a grain of salt as your mutlimeter won’t accurately measure it. The only thing that the measurement will really tell you is if one cell’s IR is significantly different than the others, that cell might be faulty or at least problematic and possibly unsuitable for a high current discharge.
Stated differently, it’s not a deal breaker if your cells are measuring ‘out of spec’ as long as they’re all similar IR. You should measure each cell multiple times as well and make sure you’re getting relatively consistent results.
Kweld is a good choice 
I’d also recommend springing for some pre-cut nickel. Makes the job MUCH easier.
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Thx bruh, This helps me a lot.
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Arcing…maybe, why, how? I bet one of the cells is loose inside the module. That screw looks like it’s sitting higher than the rest. Is it safe to tighten it back down, Will I short it with the allen key? Maybe it’s better to just spend my time ordering a kweld, pre cut strips and a PCB from @DuckBatterySystems.
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