Manual button top for 18650?

Batteries and Chargers Rechargeable Batteries
1

Hi guys, long time lurker not much of a poster~

Anyways like many of you guys may have noticed, the nasty lil springs on the nanjg 105c drivers tend to destroy (dent) positive terminals of batteries. So here’s the thing, I’m pretty sure many of you have noticed but the button top panas aren’t affected by the springs, apart from some deep scratches over time.
Well after a few 18650B deals, I have ended up with a few flat tops that i don’t want to damage, and was wondering if any of you know where places such as fasttech source their button tops from so i can stick them on my own cells! Dented terminals never again!

P.s. Does anyone know how much force the positive terminal take before you damage the battery? (Ie. when you stick a flat head screwdriver under it and push it back out.) I’m too scared to test it, and a video of anyone doing this would be good :smiley:

2

I say: Bump stops.
Prevents springs and flattops being squashed.
So, put some non conductive ring of some kind around them springs.
This would also solve the spring problems with gun mounted lights, which get destroyed because of the recoil of the gun…

3

Don’t mess around with the battery. Fix the problem. Either grind down the sharp part of the spring or add a cap to a new spring.

4

This is why I created this, with buckets piece of uhmw.

5

I like the bump stop idea! However some of my torches (convoy S4 etc…) don’t have much room to mess around…Probably go for the spring idea

@bushwhacked where did you find that cap? is it something like this? https://www.fasttech.com/products/0/10002023/1145100-5mm-2mm-brass-pillars-for-electronics-diy-10-pack

Anyways I’ll probably still keep a lookout for the button tops… sticking a metal cap on seems so much easier then resoldering all the drivers…. =/

6

This is a video of a guy who stuck a screwdriver in his batteries.

7

Blob of solder on the batteries is how most seem to change flat tops to button tops. Or little magnets, most of the Chinese vendors seem to sell them I think.

Dont know about panel beating the damaged ones, unless im missing something even if I knew how to put a screwdriver the wrong side of the terminal, I dont think Id like to do it to an 18650.

EDIT: Like he said… well thats embarrassing, the video is borked. Hmm … Maybe like he said….

8

I actually made the cap from gilding brass. Poked a hole in it, fed solder braid through the hole and bent the edges around the spring. Soldered it all together and it works awesome.

9

I imagine every tube shaped batt compartment with springs / sprung contacts
would be helped with a thick rubber (o)ring with outer diameter of 18 - 20 mm in the head and the tail.
It will stop the bumps smoothly.
Vehicle suspension always has rubber bump stops for the same reasons.

10

I put some of these 2mm brass pillars on my flattops, just scuffed the top of flat top and immediately smeared some flux, filled the cup with solder, placed on top, gently held with needle nose tweezers, held soldering iron to top with a tiny dab of solder to aid in heat transfer, as soon as it settled flat was done…let cool and then cleaned with alcohol.

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how much does soldering the brass pill on top help? Did it stop the denting of your flat tops?