Heat Safe Heavy Guage 18650 Soldering

How to solder heavy guage wire to 18650s for serial connections for flexible packs safely, with zero possibility of heat damage…

  1. Cut small nickel tabs about 20mm wide.
  2. Rough up one half of that nickel tab ready for solder.
  3. Use flux and solder to ‘tin’ the roughed up half of the nickel tab.
  4. Cut small length of your heavy guage wire (10awg in my case).
  5. Tin each end of that wire.
  6. Solder each end of that wire to one of your tabs.
  7. Use plenty of solder for a good solder joint.
  8. Now spot weld those tabs to your 18650 cells across the series connection.
  9. Done! No chance of solder heat damage to the cells…


This is a very nice solution!

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something else you can do is solder the wires between the cells and not on them. that distributes the heat across the tab and doesn’t get any one cell too hot. Still need to keep the total soldering time down to a few seconds though.

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here’s an example… although i’m pretty sure its obvious what i mean…

I really really like the pre soldered tabs idea though. That might be the quicker way to do it, actually.

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Very obvoius :wink: Although, I still think there’s a chance for some possible heat damage with this method… but I’m sure it would be fine to be honest. These 18650’s are pretty hardy cells actually…

also nickel wicks away a lot more heat than people think.

but this tabs idea… that would allow me to prefab parts of the evolve packs.

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Exactly! That’s what I’m doing… getting them ready in bulk :wink:

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