Building a flexible pack

So the summer is creeping closer and closer, and I am sitting on 2 builds that I’d like to have done for July. Both builds need clever battery packs, and I’ve not built my own pack before.

If I do, I was thinking about how to build in some flexibility into the packs, given the boards I’m working with are the split channel Hummie deck and the Haya.

I was thinking it would be possible to put together nickel strips 4 cells long, with flattened copper braid pieces joining 2 of them, allowing the pack to flex. The nickel strips can be welded to the cells in the necessary orientation after the two strips have been joined/soldered with the copper braid sections.

Any thoughts about the safety of such a pack? Performance?

yup, that’s how i build my packs.

see if you can find some inspiration here:



I drew inspiration! What if I pre-build the above templates, then spot weld those templates to my cells? What limits should I expect?

The nickel strips are .15mm * 8mm wide. The tinned copper braid is 1/4" wide (yes, @longhairedboy, grounding strap!) , and listed with 32A rating. I plan to triple up the nickel strip, and thoroughly protect the folds using any means necessary. The layout of the cells will be as such: Pack

with the “templates” located anywhere + - touches. Any foreseen issues/concerns? This is to allow for some flexibility in the pack with Hummie/Haya decks, and the folds will need to be orientated up so that the flex in the deck coincides with the flex in the pack.

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You might need to use the pcb method above, or @Eboosted style fold over bus bar style, because the tinned copper braid probably doesn’t flex enough, to go directly between the parallel cell groups.

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If you have an extra ~.25" of room, you can always use some nice silicone wire instead of the copper braid. It has finer strands and thus handles flexing even better.

The issue with the PCBs is that they add D and not W or L. There is plenty of L to give in the Haya deck, tiny bit of W, but not so much D.

Silicone wire folded in half seems extreme.