So Zach, if i sent you some batteries, (used but all around 3.52v) could you supply a bms and make a pack? If so, what what would that run me?
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How do you manage to keep your welder cool? I had to stop so many times when I was welding my 12s7p simply due to how hot the electrodes got.
The connector on the welder battery gets pretty hot too to be fair tho
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I do 6 dots at a time then chill for at least 30 seconds, heat sink dissipates faster the hotter it is so I rapid the 6 and wait
Doing a weld then waiting 5 seconds runs hotter overall
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Dude you’re too nice, looking at your stuff is what got me started, I’m just trying to live up to the gold standards around here
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As long as the cells are not connected I can, but they are far more likely to drift so it voids the long term warranty
I can simply negate the cost of cells but the per cell cost is increased to $4 for the time to grind the cells clean and bring them to the same voltage
It’s undoubtedly better to use new cells from a trusted source, and the whole process would be faster
Edit: the $80 base cost doesn’t change
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People are serious about batteries around here. At this point, i’m learning from them not the other way around. I learn something new every day here.
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I always stalk certain threads for tips and inspiration, some people have genius ideas
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Ah interesting, I’ll try out this method on the battery I’m working on this Thursday
There was an hour where I marked the time in tinder swipes, for me it’s 6 welds to 6 swipes 
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dremel surgery.
have you built a balancing rig yet? I have this thing i can slip 18650 pgroups into, i still have to build one for 21700s, but i use a standard dual 6S balance charger with it. I’ve been wanting to get one of those fancy “up to” 14S balance chargers and expand it, but they’re so expensive.
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Not yet, but I did upgrade the Dremel battery to 30Q cells 
I feel like you would remove the shrink wrap in a jig you slide groups through?
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Oh boy… lmao
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Haha usually it’s Reddit
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yeah i pre-balance them immediately after welding the pgroups usually, but i also have a spaghetti web of resolderable balance leads that can connect to it for emergency pack re balancing.
I think it would be cool to power a balancing rig with a flexi-bms too. Some kind of menu system would be needed though.
sorry i’m derailing.
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How much voltage tolerance do you have for making a group? That 12s6p I have on the bench had cells that varied so I matched them so the whole group would be balanced relative to the others, had to spend like an hour doing math to get it right but they all were 3.43V after welding so it worked
Also lol you’re good, it’s still battery shenanigans
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within a tenth is fine but really it doesn’t matter much unless its wildly off which might indicate a problem with the cell. they balance inside the pgroup once welded, so then if you prebalance the pgroups before welding them or wiring them into series, its gold.
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They were all in the 3.40V to 3.45V range, I did the welding in the order of voltage so the internal balancing isn’t as rough, didn’t need to balance them after welding
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its like sharks in the womb. They have to struggle to understand the work they’re about to do in our boards.
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Haha you right
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