Anyone ever see a battery top like this? Ideas for the cause?

[Mooch]

This is a new cell from its original undamaged box and what you see is identical on three cells of the same type. I have some thoughts about what caused that outer ring roughness but would love to hear what you think does this. I've never seen this before.

If you know what this cell is, please don't say anything. Thanks.

 

[d4gger]

is that acid etching?

 

[BigGOOSE]

Hmmmm


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[sonicbomb]

Pitting like could be chemical in nature, or it could be due to bad machining.

 

[Mooch]

Hmm.....chemical/acid...hadn't thought of that.
It appears mechanical but I'll try to get a better picture, not as washed out.

 

[disallowedword]

I been lurking this thread anxiously waiting for the answer, but was thinking some kind of acid too. Maybe a crew of 8yr olds with ball peen hammers are crimping them shut?
I bet if someone visited some of these factories with a video camera, a documentary would be be so ridiculous nobody would believe it.
I remember as a kid, seeing brand new eveready batteries with some white crusty powder around the seams, but back then we were invincible, lol.

 

[edyle]

maybe they bought packs of these and squeezed them onto flattops?

$1.23 Stainless Steel Pointed Top Cover Cap for 18650 Lithium Battery (50-Pack) 50-pack at FastTech - Worldwide Free Shipping

 

[opticruby]

Is it where they've been thrown in the seconds bin to be sold-on, re-wrapped and stamped with over-inflated Amp and mAh ratings.

Or was it caused by the machine when the top of the tube was crimped closed over the positive insulator.

 

[disallowedword]

The more I look at that pic, the more it looks to me like a sleeve that holds the cap on, and someone went around it with a hammer and punch (several blows). Or more likely a machine cranked up beyond its limits. Would like to see the cull pile, probably some smashed batts in there.

 

[Mooch]

A better picture...I hope...

 

[disallowedword]

A better picture...I hope...

View attachment 491914

Looks to me like the machine didn’t do the job, so someone just whacked that baby on there with a claw hammer and 3/8" drive extension?!
I think China takes the 1950's American ethic "Waste not want not" to an entirely new level. IMO they’re QC parameters have always been dictated by sales volume rather than safety.

 

[opticruby]

It still looks to me like the machine thing because some of the lines are straight.... maybe pressed to fold the top.

EDIT: I keep looking at the pic and something keeps making me think it maybe something to do with the cells being harvested from something, somewhere....

 

[Mooch]

My thoughts are that the cells were opened, something done, and then resealed.

I was originally thinking it could have been a chemical/acid. But in taking that second picture I noticed that the black sealing ring under the "rolled" can top is also wavy, like it was being compressed due to not fitting perfectly. Or overcompressed or squeezed out.

 

[d4gger]

That second picture looks exactly like the almost worst case example of a can (beverage) can that was seamed with the seamer head covered in shavings.. While set too low (too much pressure).
I think those are original manufacture with the machine unmaintained. I doubt they even bin those, someone probably scavenges manufacturer dumpsters.

 

[WharfRat1976]

It's a poorly made battery is all.
Also, the sun will be rising in the East and setting in the West tomorrow.

 

[Mooch]

That second picture looks exactly like the almost worst case example of a can (beverage) can that was seamed with the seamer head covered in shavings.. While set too low (too much pressure).
I think those are original manufacture with the machine unmaintained. I doubt they even bin those, someone probably scavenges manufacturer dumpsters.

Interesting, thanks!

 

[sonicbomb]

Tool striations from a badly setup manufacturing line. That's what I think.
Not all that groundbreaking, so heres a picture of a kitten.

Daawww

 

[Pete54]

I see markings that are very similar to what was found at Roswell. I believe these are actually batteries made by ancient aliens, that were dug up and re-wrapped and marked as 60amp 3,000mAh batteries.

 

[sonicbomb]

LOL, only aliens can make a 60 amp CDR battery, they need them for their ray guns. Note they also favor copper,

 

[Mooch]

Tool striations from a badly setup manufacturing line. That's what I think.
Not all that groundbreaking, so heres a picture of a kitten.

Daawww

The kitten did it?!?
Gosh darn, dangnabbit!!