Battery clasp for three 18650 cells.

Assemble loose cells into 3p packs using a tension spring and two of the clasps.


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Printed on my RepRap Prusa i2 without support at 0.65mm extrusion
width and 0.4mm layer height, single-perimeter, 20% infill.

I use the clasp to charge loose li-ion cells in parallel. One could
also wire the clasp for series connection of the cells, but I
recommend against that, as one needs to be much more careful when
assembling a pack, and accidentally short circuiting li-ion cells is
something to avoid at all costs.

The banana jacks are experimental. My specimens are still going stong
after about 50 insertions using 0.6mm wire. The jacks appear to work
best with plugs that have a "cage spring". Classic plugs with a
"banana spring" work too, but you need to orient them so that the
spring opposes the wire for reliable contact. The "bunch of springy
wire" style plugs don't seem to work reliably because the contact wire
sets itself between the spring wires instead of compressing any of

As an alternative to banana jacks, the 4mm holes could be used as
strain relief for stranded wire soldered to the contact wires.

Materials and methods

- A tension spring.
- Approx 50cm of nickel/silver/gold plated wire of 0.6mm diameter.
- Filament clippings to anchor the spring.



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05c026b73c89410a114b66062add7971?default=blank&size=40Tamion added this to the Elektronik collection ago
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C547b810270b9980d0200c7f15c58e0a?default=blank&size=40ThomasBe added this to the tools collection ago
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