I suspect during manufacturing that something was trapped between the shell and wrapper and reacting with the metal shell.
I wouldn't call it controversial. I gave what I think is a plausible theory. It's definitely anecdotal, which I thought was obvious. I know you're still angry about being exposed, but we don't have to drag in into every thread. We are adults, rights?As usual, you post something controversial as having some scientific evidence, and when asked to document it (and not just anocdotal here say) you can't back it up. I generally back my information up with links that readers can verify for themselves.
I would have been fine with all that, but you had to "go there" and post, "Bro, do you even science bro?". That was a personal slam towards me, which you have admittedly done in the past. Hence , my return comment. Yeah I'm old and sometimes I'm grumpy. I won't be commenting further to you, you're going on my ignore list. My appologies to ECF for going off topic.
There are threads on Reddit and Candle Power about it. I can't find the threads, but I did some Googling when I ran into the same issue and that's what I read. I don't care if anyone believes me. I'm saying the discoloration and spotting is fairly common. The fact that it happens in flashlights leads me to believe that it isn't juice causing the discoloration. Believe what you want.
None of these batteries are still in my rotation, but I don't believe them to be "dangerous."
All my Sony's are similar. They have larger dark spots here and there. One guy I know who sub-ohms (as do I), has the same thing on his Sonys and everyone that works at the B&M i go to have the same issue. And there are no performance problems either. I was told it was heat spots and that it discolors after being heated up so much when sub-ohming. My wife who doesn't sub-ohm doesn't have dark spots on the battery like I do. And we got the batteries at the same place and time.
I wouldn't call it controversial. I gave what I think is a plausible theory. It's definitely anecdotal, which I thought was obvious. I know you're still angry about being exposed, but we don't have to drag in into every thread. We are adults, rights?
Good to know that B1sh0p and thanks for that info. I believe that.
What I'm interested in is why these batteries are doing this and you were talking about knowing they could have minor leaks in them which though possible, I suspect would only affect a few batteries per million. You also talked about the batteries venting through the wrap, which doesn't make any sense to me at all.
If the batteries had that many micro-cracks in the casings I would consider them dangerous. I think it's from some substance between the casing and the wrapper, but that's just my theory so I won't state it as fact. So far all we have are theories.
I want to know what's really causing this
It's plausible that it's arcing as well. If it was from the batteries themselves heating up, one would think the wrap would shrink. Mold and juice are just too unlikely.
I have a battery with this exact issue, mine got a small amount of eliquid in it and those spots showed up soon after. I'm guessing it's either mold or the eliquid oxidizing the battery case causing little rust spots or something. I have 5 of the vtc4's and only 1 has this issue. I'm actually still using that battery here and there, I'll probably throw it away and get a new one. The voltage is fine on it and it operates and charges as normal.
Keep us posted, I will cut my wrapper off before recycling mine and report back with more details.
You say larger dark spots Wilson, how do they compare to the batteries from the OP? A picture would be great
How low in resistance do you go with your builds? I vape at 0.4 ohms all the time with these batteries and have gone down to 0.3. I have large sections of slightly darker spots, but nothing that remotely resembles what we're talking about here.
I felt I could get a better picture...
Notice there is what looks to be an oily substance under the wrapper as well. I cannot be certain but, I'm am quite confident that this is eliquid and the spots are a result of that eliquid, whether it be oxidation/rust or some sort of mold/mildew. I've not gone below .4 ohms with any battery and done .4 ohms with all my batteries. I do not believe this to be any sort of venting on the part of the battery. It still operates correctly in all aspects that a battery should.
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The only reason I don't think this is the case with mine is, there was no "oily" or "liquid" substance under there for a long while. This started with one day taking the battery out of my vape bag and noticing something that appeared "wet" under the label. Soon thereafter, the spots started to show up. When I first noticed this "liquid", it was a substantial area of the battery and hasn't changed much since it first appeared. It is surely some type of moisture, as I can run my thumbnail across the wrapper and "move" the moisture around under there. As stated before, I will peel the wrapper off and check it further before recycling the battery and report back.If this was liquid related wouldn't we see it happening with other brands of batteries. I still think this is something trapped under the wrapper during manufacturing or possibly a reaction with something within the wrapper composition it's self.
The only reason I don't think this is the case with mine is, there was no "oily" or "liquid" substance under there for a long while. This started with one day taking the battery out of my vape bag and noticing something that appeared "wet" under the label. Soon thereafter, the spots started to show up. When I first noticed this "liquid", it was a substantial area of the battery and hasn't changed much since it first appeared. It is surely some type of moisture, as I can run my thumbnail across the wrapper and "move" the moisture around under there. As stated before, I will peel the wrapper off and check it further before recycling the battery and report back.
Let me know your thoughts.
Sorry, I wasn't really clear before. I suspect the eliquid got on the battery as a result of a leaky bottle of juice in my vape bag. I won't test it on a perfectly good battery however, I'm sure if you place a drop of eliquid where the wrapper stops on the bottom of the battery, juice will get right under the wrapper if left to soak for some time. I no longer carry my batteries loose with eliquid bottles, so we will see if this happens again. As far as heat, none of my other batteries look anything other than new and they've worked harder than the battery pictured since I rarely use it anymore.I just find it hard to believe e-liquid could get under the wrapper but I guess possible. Maybe the heat is breaking down the wrapper it's self.
The only reason I don't think this is the case with mine is, there was no "oily" or "liquid" substance under there for a long while. This started with one day taking the battery out of my vape bag and noticing something that appeared "wet" under the label. Soon thereafter, the spots started to show up. When I first noticed this "liquid", it was a substantial area of the battery and hasn't changed much since it first appeared. It is surely some type of moisture, as I can run my thumbnail across the wrapper and "move" the moisture around under there. As stated before, I will peel the wrapper off and check it further before recycling the battery and report back.
Let me know your thoughts.
I'll have to get a picture. But the dark spots are a bit bigger and range in different sizes. I've seen batteries that have dark spots an inch big. However, mine are not all the same size like the OP. I've never unwrapped one to see whats on the other side but the way it looks from the outside resembles what I see on mine, just a different size.
My builds vary but the lowest is .12. The guys at the shop vape under .1. And those are the ones that I see get worse than mine and the OPs. Since my wife doesn't have any of those spots then I have to assume it is normal for sub-ohming. I got told once that its just the wrap reacting to the heat of the battery. But that still doesn't explain the OP's dot in the middle of those dark circles.