Also what thickness is your nickel? That matters too.
Itās 0.2mm
Maybe itās too thick for this one?
Maybe I have only used .15mm
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Iāve never used one. But from what Iāve read, the sunokos arenāt going to do 0.2 very reliably if at all
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Angle of the pen is some thing worth playing with. It looks as tho this is most likely as the burning is heavier on one side. Sanding tips thay look very sharp in the pic hard to tell and I also fined apply a little more pressure to one of the terminals help canāt rember if itās the + or - that is most likely to burn but there is a Physics reason behind it.
Cleaning the battery surface and nickel with IPA you might fined that the nickel tip or battery could have a layer of some thing left on them cleaning can some times help
I also like to wiggle the pen around just befor welding push the strip in to the battery to Guarantee good connection.
Flatten the nickle if itās bent and crumpled it doesnāt weld consistently so try to keep it flat.
Is the spot welder heating up and caps having time to recover between sets of welds.
Hopefully that will give you a idea on things to try and work out how to improve the consistency
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Thank you for the tips! I will definitely pay close attention to these for my next battery!
@Mudders it is charge only. My settings are for personal preference but if you want to copy go ahead
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Hey guys. In a bit of a dilemma here: I realized that I donāt have enough space in my 23mm high Haya enclosure to use PCBs and wires to connect my P-groups. Even without the PCBs, I think this deck was designed to have the P-groups be connected on the sides, not over top.
Furthermore, the only orientation in which my battery will fit the deck is if the P-groups are next to each other in a end-to-end fashion. (Minus of one p-group right adjacent to the plus of the next one.)
Iāve only seen a few batteries built this way, and was wondering what would be the best way to do so. Here are a couple of options:
A) Weld the packs together with nickel strips from cell to cell, and then bend the nickel like this: (side-view)
B) Weld all terminals of the p-group together, with a single nickle strip, and then solder on wires to one end, and then to the other end of the next p-group. Like this: (top-view)
C) I could buy copper braid and do the same as A
D) I could buy copper braid and do the same as B
Option A is nice because I donāt risk overheating the batteries with my soldering iron, but I fear the nickel strip might break in the bend. Maybe it would be fine if I put something like a flat lego piece between the packs, so that the bend isnāt too sharp? (Or better yet, a piece of copper wire)
My last battery I built was with method A. I folded the nickel over and since 5 strips of nickel wasnāt enough to pass all the current for my 12s5p battery I soldered copper braid strips in between the nickel strips. Itās a bit over kill now since it can handle about 200amps. I would do A with added copper braid but thatās just me.
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I wish I took a pic before I shrink wrapped it and installed it but Iām terrible about taking photos.
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Try bending nickel with your hands, it wont break especially in a battery as you bend it only one or two times in its lifetime
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well, I was worried about what would happen under vibrations, but I think Iāll solder a copper bar in the middle of all the pieces, and then it should be rock solid, especially in the stiff Haya.
Worried as in your welds breaking?
The nickel itself, and yes, possibly the welds.
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if your welds are that weak you need to change your welder, try pulling on the nickel like a maniac with some pliers and if the weld spots stay sticked to a cell then your golden 
Question is this diagram correct? Do I hook up my last 13th balance lead to my bat positive? Also does anyone know for sure if I solder to p-1 for discharge only? Or do solder to p-/ch- for discharge only.
Need some help from someone far smarter than me
Iām building a battery for an EV, aiming for like 44+S and 2+P, with the cells being LiFePo. Now the first parallel group will be Headway 38120HP and the second group I was hoping that I could just use some cheap high capacity cells instead of using more Headways and wasting the available amperage. My question is, is this even possible? If so, what will the continuous current be? And how will charging work? Any insight would be amazing, I hope I have made some sense
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But the second group still being lifepo4?
Just wanted to make sure. Couldnāt fully understand from your comment.
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Yeah still the same chemistry, the brand CALB has cells that are like $1 or so an amphour, just not sure if doing things this way is possible
Edit: technically Headway is also $1 an Ah so like idk