I was speaking about the pcb which you ask what it is. You lay that pcb (the thing you thought is a bms) on top of your parallel pack and than connect the nicke strips to it.
Exactly, do more practice soldering and gain a little more experience before you burn your house down. I really don’t like the joints, not only because they are soldered badly but also because they have sharp edges which need to be protected not penetrating into the cells.
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This is bad?, im doing this:
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Why not have one tab directly bridge the two cells?
becouse i dont wanna make the sold in the cell, and may be i go too far and the cell goes hot, and burn. i dont wanna soldering close the cell
becouse i saw few videos, and some guys burn the cell
and guys, i really read a lot, i have a bucket water with salt (i don’t know why have to put salt)
When I build my pack 12s4p, I welded 4 cells in parallel together in one strip and I quick soldered the bridge between cells onto a 10 awg wire If that helps
Somewhere along the line you’re gonna solder on tabs that connection to a cell.
i wiil cut the edges
it was sopt soldered or like me, normal soldered
The soldering is much easier and the finish and weld much better for regular soldering irons
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Please rebuild that battery. It’s a blaze to come. Read, watch vídeos, do more research. Then when you know exactly how to do it go ahead. Follow the advices you have been given.
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Bottom line is your trying to save money in a task where you can’t cut corners. Just spend a little extra and get the spot welder or buy a prebuilt battery. You may lose a little money in the learning process but it’s far better than loosing your entire build or home. Look at some of the shit that has happened when batteries go wrong and scare some sense into yourself.
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Reading through this thread I’m suddenly very stressed out.
NO! Take it all apart before you burn down your house.
And then read some battery build threads. Please.
If you can’t see the difference between what you’re doing and what other builders are doing then just throw all of it in a steel can and set it on fire already.
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Use kapton tape
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Right kapton on the finished project. I usually just use a little cheap electrical tape when I set something down mid process just to avoid accidental contacts.
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Electrical tape and duct tape have gummy adhesive that can dirty things up though
I use electrical tape in process as well. It’s only gummy if it gets hot.
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Yeh if i were u @pedro I would isolate / wrap every part of battery to avoid any shorts…
Also these long strips doesnt look good at all, cut all corners u can and probably glue everything in place, if u really plan on riding with this battery.
The vibrations and road impacts are immerse. If u wont protect your pack (also extra padding material in between / around cells) it wont turn out well… it might either short or just disconnect during a ride.
U could have soldered a bit differently. Making a ‘>’ shape of nickel on top of cell, then folding it flat afterwards and glue or solder in place.
Also 14awg wire would have been easier to solder than 12awg, basically u need fat wire for serial connections and smaller wire can be used on parallel ones (unless current goes through them anyway)
If this 
can happen to even an experienced builder with good tequniques you can never be too carefull.
Vibration is really a much bigger issue then people think. Any tiny movement can crack metal or wear through insulations.
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