Very nice
How tight was the soldering job on the 7 pin connector?
Easy. Just solder first the wires to the plug and than to the pack,
or use a jst connector in the enclosure between the pack and the plug.
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I saw that one but it looks slightly different
looks good, maybe a little toasty on the nickel to nickle, maybe just the picture.
what cells are those? and how are you going to make the series connections? you don’t want too many angry pixies moving along that nickel bus…
also, I saw your thread looking for a bms. I have one I can part with if you promise to make a build thread 
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Yeah I burned through on a couple of the nickel on nickel welds, I’m using 0.15 x 8mm and turned it down to ~25j but I think it’s still a tad hot. They’re 30q’s in 12s5p, I was planning on using 3x 14 awg silicone wire for the series connections but wanted a sanity check before moving forward.
Here’s my ongoing build thread: the Ba'al Buster :: Demonseed 42 :: BN 270 trucks, mounts, baseplates :: TB 6380 190 kv :: TB AT :: 12s5p 30q :: ESC = who knows?
I figured I’d get more targeted battery feedback here but I’ll document actual progress there.
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that’ll be plenty. sounds like you did some homework 
nice work on that build thread, pm for that BMS
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you should use a crimping tool
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and if I don’t have that what can I do, directly weld the tabs?
you mean solder? idk if it sticks yeah but you’ll need a soldering iron with a big thermal mass
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Get a screwdriver and a hammer. Shove the wire into the lug. Put the screwdriver near the end and hammer down just until the wire is held in. These turn over and do on the other side. Now once its held in, lightly hammer the rest of the lug until the wire is VERY firmly held in place. Don’t just smash the lug repeatedly, you’ll break it. Just hit enough to get it to deform
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Pliars and a rubber band should be able to hold onto the crimp. Hold the soldering iron to it for a whole and ‘fill’ the hole with solder. Insert the tinned wire and wait for it to all melt together
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I read a bunch of the net on crimp vs solder vs crimp and solder I came away thinking opinions really vary.
If you have a blow torch you might be able to use that to help heat it enough for the solder to flow. But would probably be easy to over heat it and mess it up.
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If clamped down with enough force, crimping will be more than enough. The wires need to be squeezed into the space as tightly as possible to allow for maximum current transmission
Are these “cell level fused” because the nickle is thinner on one side?
Why use a PCB if not cell level fusing?
Why need a PCB to do cell level fusing couldn’t you still do any other bus bar method?
one would think my questions would be answered here:
https://github.com/akhlut/BATT-PCB/wiki
Why use a battery-backer PCB? Well, there are alot of advantages!
- Flexibility - the packs are inter-connected with flexible wiring and not a monolithic block, so the pack can flex with the board as needed.
- Safety - using a PCB allow you to implement cell-level fusing, dramatically reducing the chance of a thermal runaway due to a bad cell in a p-group.
- Modularity - Repairing a battery is simple - undo 3 connections to the bad p-group (serial in, serial out, balance) and remove it. Replace it with a new p-group, re-make the connections (serial in, serial out, balance) and you’re on your way.
aren’t 1 through 3 here all doable with any kind of bus bar as i see people do with nickel? why the PCBs?
If you are planning on using 3 x 14awg, i would do it like this. Don’t dis my sketch skills.
You only need to tack the strips together with one weld, and then use the solder from the 14awg to bridge the joined strips more securely.
Heaps less work and less nickel too. That series bus is unnecessary seeing you already have a parallel strip.
Examples:
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I’m all for less work 
. Why have the 5 tabs in the diagram but use 3 in your first photo and only 2 in the second?
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