I’ve got two Panasonic NCR18650B that I have been using in Convoy S6, and they barely fit. I just purchased some unprotected cells cheap, and these may be of better use in the S6 than in my 2x, 3x, and 4x 18650 converted Maglite D.
In order to save some money, I’d like to add solder bump to the NCR18650B in order to use them in series.
Can I do this without messing up the protection circuit?
Good question ! But don’t put a lot of heat on the battery.
What about using small earth magnets ? Although , I’m
not sure if the magnets can somehow compromise the PC.
Haha DERP!
Yea that’s probably a better option!
Can get those dirt cheap off of FT for $0.82 (don’t look in the flashlight accessories section). $0.60/each for 5+
I’ve used those magnets on some of mine. I don’t know if there is any noticeable resistance in them but they work fine. I put a couple of tiny dabs of glue to keep them secured.
On the other hand I wouldn’t be too concerned about soldering blobs on them either. At the time I didn’t have a soldering iron.
You shouldn’t damage the pc as that’s at the bottom, well away from the heat of the iron (although I once damaged a circuit using a faulty soldering iron, so use a gas one now on anything with a chip in it)
I’m always more concerned with damaging the ptc and other inbuilt protections on that end of the battery by applying to much heat
I normally put them in the fridge for a few hours before soldering blobs on
On single cell lights I just use magnets as mike c suggested, just don’t use them in lights with magnetic control rings or sliders
Or on multi cell lights, as even glued magnets can come loose and cause a short
I have solder blobs on all of my unprotected cells and on the nitecore protected 14500 too.
Never had any problem.
I use a kester flux pen and normal Solder with lead. Just takes a moment and works perfect without messing around with magnets.
I tried using magnets on flat top AW’s. Worked pretty good until one of the magnets split in two. Only luck saved me from having the magnet short the pos end of the 18650 against the wall of the light. Solder blobs seem much safer.
+1 This method takes a good 0.5secs to get it done. You basically just drop the solder onto the end and that’s it.
I did this with my NCR-A using a 60w soldering iron. It may seem like a lot of heat but it is perfect for this because you only apply it very briefly, and the battery doesn’t get hot. Flux is a MUST.
The solder blob will eventually wear away, so it’s a better idea to use a small copper/brass spacer like Texastoasted mentioned above.
I’ve ordered a bunch of used Samsung 18650 2600mAh laptop pulls and they are flat tops.
But decide I would rather have button tops.
Another other threads about adding solder bumps or something else to change the flat top to something with a bump?
I noticed on some of the lights, withcarriers especially that will not take flat tops, one could also use the brass buttons 6x2mm that RMM has (a whopping $.2 ea) and solder them into the carriers so then flat tops unmodified would work.
Your milage may vary.
