Black Ring on 18650

[Anthony1982]

Does anyone know why this is happening to my battery? This is my 3rd one.

I'm using a Copper Cartel mod, 0.4ohms, efest 18650 flat top, the mod has been cleaned throughout, no dirt on the threading. The ring is etched onto the battery. It needs to be scraped off which I don't want to do in fear I might puncture it. I've tried wiping it off with alcohol and rubbing it off with a pencil eraser which doesn't do much.

Check it out. Any advise would be appreciated.

 

[Kaezziel]

Looks like the outline from your firing pin... how does the outer edge of the pin look?

 

[nynvolt]

That's from tightening down your end caps too tight on the battery. Looks like your contacts must be stainless or some harder metal to scrape it that way. Try to adjust the battery rattle out without going too tight. I've got, to a lesser degree, the same marks from over tightening on occasion.

 

[Griff.J]

That looks like the results of electrical arcing? If it was from tightening down a contact too much it would be shiny, not black like that.

 

[dice57]

Umm, all I know is that when my girlfriends pee test came back looking like that my wife kicked my out, or something like that ummm, yeah, either your reefing down on the switch to tight, or something is rubbing off from you switch insulator.

Firing button hasn't been getting warm lately? has it? Which Efest batts are you using? Purples? what's the continuous amp ratting?

Vape long and Prosper.!!!

 

[Kaezziel]

It's not gonna arc in a perfect circle like that... that is definitely from wear/contact... it can be dark like that, depending on metal composition of the battery bottom terminal and firing pin

 

[Anthony1982]

Thanks for narrowing it down. What would you recommend I do to avoid the pin and battery from arching? (If there is anything I could do?)

 

[Equilibrium]

It doesn't look like an electrical arch to me. As Kaezziel stated... it's too perfect. Does the button get hot?

I think you're cranking down on the cap too tight.

 

[Anthony1982]

The button is getting hot with the 2 batteries that have the dark circle (possibly from a bad contact with the firing pin). I just bought a new purple efest where the button isn't getting hot, but you can begin to see a circle begin to form.

I think you guys are right. I'm over cranking my threads. I'm gonna try easing up on them over the next few days and will see if the ring begins to form on my new battery.

 

[Griff.J]

That is the negative side of a mechanical mod.. no metal contact should be cranked down against the negative side with a bottom firing button mechanical.

Cartel Mod:

Are you turning the fire button while it's being pressed? Also if it was many little arcs from a bottom contact that turns it would make a black ring. I'm not saying it is for sure arcing, just that it could be. That black ring looks splotchy to me, instead of having markings that would indicate the contact turning against it.

 

[Anthony1982]

Thanks for all the help. I think I figured out what the issue could be, lemme know if it makes any sense. The button is getting fairly hot whether I crank down on the cap or not. I measured the resistance on the spring and its coming out to 0.5 ohms, which is exactly what I have my coils setup to. So I changed my coil setup to 0.6 ohms and swapped out the Cartel firing spring with an old Nemesis spring I was using (measured at 0.2 ohms) It doesn't for perfectly but it does the job.

The button doesn't get as hot as it used to and seems to be hitting harder than before. Ill keep an eye on it over the next few days and will update this thread.

 

[Griff.J]

Good investigating. I knew it wasn't form cranking down the button. Not on that style of mod. Mechanicals can be dangerous with all this sub ohm stuff going on. People holding their mods with towels because they get too hot. Just insane IMHO. (not saying this directly to the OP. Just speaking in general.)