well, I was worried about what would happen under vibrations, but I think I’ll 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
I’m 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. Couldn’t 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
I think @MoeStooge does similar things with lipos. One smaller Ah pack with high discharge close to the esc and than a low discharge high Ah pack in parallel behind.
Don’t know about his charging routine thou but I’m sure he could give you some more information about all that.
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The long wires are for linking the packs? Do you beef up that end of the parallel connection also?
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The nickel strips are doubled on those series connections. 10s8p + 2s8p
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Good info to have!
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What you decided to go with for the balance connector? The big 13s plug?
Yeah that massive 16 pin one. Will be mounted to the side of the monster box and connect to the plug in the photo.
Ive got some gx20 connectors on the way, but I reckon they will be really hard to solder to as they are much smaller
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I just finished soldering the BMS, so I tried connecting the charger, it immediately sparked and the charger got fried and started smoking. I tried changing the charge port out, that didn’t help. Any ideas what the problem could be?
Photos are worth a thousand words. Have you checked your polarity?
If it just sparked after you connected the charger I would double check the polarity on the charge port.