Battery safety ?

[Coils&clouds]

so I have a couple sets of the brown 20 amp lg 18650’s I noticed on one of them the positive end is starting to dent in just a tad. Should I not use that battery or is that ok as long as my positive pin is very well protruding and even adjustable. Just curious ! I’m about to buy new batteries anyway being these are close to a year old. Just wondering about the dented cap what’s your guys take on that ?

 

[classwife]

Moved you to batteries and Chargers from E-Cigarette Accessories Discussion

 

[bombastinator]

That’s not dangerous. If it was a corner or the side that might be a different story though

 

[Zaryk]

I take dents seriously on batteries, especially on the business end (+ side). I always stop using batteries with the same issue as soon as I notice it. Once the metal dents, it weakens it and can make it easier to continue to be pushed in, which can lead to thermal runaway. But I have had batteries explode on me (soft shell lipos) and I am overly cautious about them.

 

[stols001]

I don't tend to take very kindly to dented batteries, period. I'd think a positive end dent (might) be more dangerous, but a lot depends on where exactly it is, and etc. Did it develop slowly over time or all at once? I'm just curious because yes, I would probably replace it and it sounds like you are going to replace, anyway, but you want to be sure it doesn't keep happening (could be new atomizer, I guess, and/or something else.

Without seeing a picture though I am going to recommend not using it. I do tend to be overly cautious with my batteries though, maybe posting a pic might help? Sometimes it's harder to gauge these things without knowing how severe and where exactly the dent is and etc.

Best of luck,

Anna

 

[Coils&clouds]

Sorry guys here is a pic of the battery the right one is ok the left one you see where the atty left a dent I got 4 battery’s I cycle through And the other three look fine did the guy at the shop sell me a used battery or something I don’t know I really don’t think my mod did that though. But I’m gonna replace it anyway. Whenever I can get sum money being unemployed atm ;-( ok thanks for your advice y’all good day

 

[r055co]

I'd toss it, batteries are cheap

 

[sonicbomb]

As long as the wrap is in perfect condition, and you are not using it on a 'hybrid' style direct to battery mech then a slightly concave positive is ok.
Ultimately it's your choice. Batteries are cheap, burns hurt, scars are for life.

 

[Coils&clouds]

@sonicbomb yeah for sure ! I agree. I like the way you worded that ! “Cells are cheap, Burns hurt, scars are for life” real talk man !

 

[Robin Becker]

I see that a little bit different. The "Crown" of the battery is the only Plus part of the battery and all the rest of the surface is Minus. In case the Plus side ("Crown") dents too much in can touch the Minus part below. In that case we get a short-circuit.
Frankly speaking, when I see the 2 batteries Coils&clouds shows...I think the left battery HG2 is too risky to use...

 

[untar]

In case the Plus side ("Crown") dents too much in can touch the Minus part below.

That's not how the batteries are designed, the "pressure valve" and PTC (material with high TCR that increases resistance with temperature, reducing current, PTC=positive temperature coeficient) are part of the positive contact
Battery Safety 101: Anatomy - PTC vs PCB vs CID

However, a dented "crown" can prevent proper venting so you're correct in saying it shouldn't touch (or be too close) the part below. Where the "crown", if it deforms, could indeed touch the (-) is on the inner side of the cylinder. Denting the middle could lead to the sides being pushed out towards (-), that's one step closer to an accidental dead short.

I'd not use that LG cell, not safe to use (especially in a hybrid mech if I understand the OP right) and it's only a few $$ to replace. A dent anywhere else in a battery also isn't acceptable, there's no telling how that may have deformed the inner layers.

 

[Coils&clouds]

Cool thank you all for your reply’s I’ve gone ahead and tossed the cell into my e waste bucket. Do you guys have any set amount of time u use a particular cell for before tossing it ? I heard a year or around 3-5 hundred charge cycles. Is there like a rule of thumb or something. Again thnx guyz !

 

[Zaryk]

I recycle mine when I notice damage, or I notice a performance drop in the cell.

 

[Robin Becker]

That's not how the batteries are designed, the "pressure valve" and PTC (material with high TCR that increases resistance with temperature, reducing current, PTC=positive temperature coeficient) are part of the positive contact
Battery Safety 101: Anatomy - PTC vs PCB vs CID

I agree with you and I think that finally we have the same in mind.

Just one thing to PTC - HG2 does not have a PTC according to LG technical specifications:

 

[untar]

That doesn't tell us if the HG2 has a PTC or not, it just means the impedance range is specified without a PTC

 

[Robin Becker]

Found this one on LG ICR18650 B4 2600mAh:

I am not 100% sure, but think that in this part LG does refer to the PTC in the battery.

HE4: http://www.batteryspace.com/prod-specs/10679.pdf (no PTC)
MG1: http://www.plsbattery.com/datasheets/LG-INR18650-MG1-2850mah-10A-18650-High-Drain-Battery.pdf (no PTC)

 

[untar]

Again, what you're looking at in the spec sheet is how they measured the impedance, not a statement about whether the cell contains a PTC or not.
It's a field named "initial AC impedance", not "safety features built into our battery" (which btw they don't list at all).

Eg here is a sheet showing "internal resistance <= 100mΩ (with PTC)" (yes internal resistance is different from impedance but that's not the point).
LG HG2 18650 3000 20a rechargeable li-ion battery

If you really do want to know if a cell has a PTC you have no choice but to contact the manufacturer.
It may also be possible that there are lghg2 with and without PTC on the market, based on what was ordered.

That all is entirely irrelevant to the thread as well as the point of the part below the "crown" being positive not negative, I really don't know why we are even talking about this.

 

[Zaryk]

To my understanding, when the positive is bent it can distort or push out the legs of the positive side and possibly make contact with the negative under the insulator ring. So the danger isn't what you can see when looking at a properly wrapped battery but under the insulator where you cannot see, until the battery is unwrapped.

 

[Robin Becker]

That all is entirely irrelevant to the thread as well as the point of the part below the "crown" being positive not negative, I really don't know why we are even talking about this.

...Or to call someone who knows that, so I called Enerdan today again (hope they don´t get disturbed too much).
Their main technician person told me, that as far as he knows PTC can built in only into batteries with up to 9A-10A CDR...but he told me that this knowledge refers to 2017.
...But he sent me via eMail some images of a UR18650NSX that has been brutally misused.
I think the images saying everything...

 

[r055co]

I recycle mine when I notice damage, or I notice a performance drop in the cell.

Yep, I toss them when they won't hold a full charge or notice a significant performance drop.

I don't abuse my batteries, I stay within CDR, charge them when they drop to around 3.6V and rotate them. I've got batteries over 2 years old and still perform well. It's all about taking care of them and not abusing them.