Flex makes me nervous- Insulation of flex battery and BMS Trampa build

Hey kids,
So I am trying to build out my first flexible board and am a bit concerned about rubz and fires and death and whatnot.

Have a Unik flex 12s4p on a Trampa H11 with Kaly drive. Looks like I can fit everything under board however curious what y’all with experience have done to shield the BMS and battery from rubz and if you have tacked down (read silicon/super Velcro) the BMS and ESCs to the board or enclosure. Cheers

I put fiber reinforcement tape inside where gaps are and black silicon from outside, then sprayed everything with Rust-Oleum Leak Seal from inside the enclosure. After this I put 2mm neopren and so far no water inside. I also added some water absorbing bags inside.

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Thanks, not as concerned about water ingress. I typically don’t ride when wet and living in Madrid means I only have ~60 wet day to contend with. Also have some rubber mat on the inside of enclosure to shore up against dust and water.

The big concerns here are constant flex (albeit small amount 16 or 17 ply board with enclosure support), friction/rubbing from said flex, and fixation of components.

Also I just opened the battery and found a spaghetti monster of balance leads so theres that to deal with as well.

this is for sure not ok, but you should be able to fix it:

just organize the balance leads - preferably so they’re laying next to each other and not all over the place that in the pic.

also, this bit gets HOT. i think it’s ok as it is here, but make sure nothing melty touches the resistors:


this is how i put my packs together:

in place of the pcb, you can easily lay fishpaper across the cells, then route your balance leads.

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Is this tape and the stuff you have just fiber packing tape?

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yup, just reinforced packing tape. it keeps the two halves together.

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here’s some more photos if it helps

and it flex in this direction


cool, well may just be re-doing the balance leads with silicon wire now and have 2x DieBieMS’s so might as well…damn it. This was supose to be a quick build before the kid is born.

Congrats on the later part

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So updates… no babies yet…

Took layers of tape off.

-Cells are Sony VTC5.
-All the wire including main leads are not silicon.

  • All the main leads, without any use of the battery- light test flexing while mocking up, are showing signs of wear - flat spots where there is rubbing - evident by black marks.
    -Single strip of 7mm nickel with non-flexible, non silicon wire making the series bridges (remember kid this is the “Flex pack” )

On the plus side:
Fishpaper Arrived (thanks NKON)
22awg Silicon wire arrived (thanks Amazon)
Fibrous packing tape Arrived (thanks Amazon)

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