Yeah, I’m testing them again, along with two more and another cell I know the capacity of from previous testing (flashlight use). I’ve got another VC8 so I’ll use them both.
I’ll collect more data. Doesn’t look promising though.
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Ouch…I’m wondering now if those are P42A’s as they would have to be really low grade junk to be that bad. So hard to say via photos.
Guess it doesn’t matter what they are though, they’re not what you paid for.
Wait…you only got 2555mAh for the genuine one? I agree with @mutantbass, that doesn’t seem like a 4.2V to 2.5V discharge capacity test. There’s still a big difference between the genuine one and the others though.
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I think he might have charged them from the voltages we saw in the IR test.
But be hilarious if the one we think is genuine is fake too. Lol
So many fakes out there trusted seller is so more important than price even if you pay double. Even the trusted seller screw up occasionally
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I had set it to a different test. It’s been a while since I used the grading function, and forgot that there are 2 different ones to test capacity.
I’m running the full test now for 5 samples and the trusted cell again. Should be done some time today. They’re looking closer to a normal capacity now as they test.
That was my bad. 
I was pretty bummed yesterday about this and got distracted while I set the charger up. Was so excited about this build and this threw a big wrench in that hype.
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No worries!
Sorry you have to deal with this kind of crap. Fakes, low grade cells, and cells with exaggerated ratings are a frakkin’ plague.
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@Fosterqc didn’t go up a gauge but does this count?.. Thanks to @BenjaminF’s wicked fast shipping I was able to switch it out with copper braid… It’s so slim!
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swagggg
Got bored so did some more test welds with my new lipo setup with 10awg wire for the parallel lipo connection instead of 12awg.
And for anyone wondering yes using kweld tips on a welding pin is possible, just if u do it take the precaution i took and wrap kapton tape around both sides of the pen.
Where are you at with those p42a?
Looks like i may have gotten the same cells you did
.
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Those damn things.
Where did you buy yours from?
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Alibaba. Let me see if I can find the retailer
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Where from…?
@Skyart @Battery_Mooch @DerelictRobot @JoeyZ5 @mutantbass
(and anyone else I didn’t tag who was interested in The Cell Saga)
Did another (proper) capacity test on the charger, and it gave ratings of roughly 4100-4200mAh for the cells (chosen at random from the batch). This seems good.
The IR of the cells (using the dedicated tester) gave me consistent results between 11-13mΩ for the tested cells. Two were 14-15mΩ.
Load tests:
Currently, I’m not sure what to think. I have noticed that one of the cans of the cells has a dent. Like it was dropped on the bottom corner. I haven’t inspected all of the cells, just found that one from the batch of 5 I picked out randomly.
Any input, feedback, thoughts, etc. are welcome.
I still have not heard back from M&A BD Electronics since I sent my email a couple days ago. I figure I’d wait until tomorrow to hear back.
I have cells to use in the stead of these, for the Prototipo build, so that’s that. However, I’m unsure what to do with these at this point. Insist on a return? Test them all and if they come out well, use them?
I’m early on in my pack building journey, having only built almost 30 batteries now. So I guess I’m lucky to only just now have run into a situation where I’d question the origins of a cell. However, here I am.
Many thanks, again, to all those who help, give info, and contribute. The gratitude I have cannot be expressed in text. So, thank you.
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Thanks for the update!
IMO you probably have rewrapped P42A’s…but no proof for that. Why they were rewrapped I do not know.
Minor dents would be consistent with cells that were rewrapped. The extra human handling to do this rewrapping often causes denting.
There’s no right or wrong here for your next steps but, personally, I wouldn’t accept cells of unknown age and condition (and not proven to even be P42A’s). I would ask for a refund and I would be mad as hell.
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Have you had a quick look at their terms and conditions? Maybe there is something in there about rewrapping cells. They are certainly behaving like the real deal. What a horrible position to be in.
Maybe they got put in a pack to the point of being glued but no nickel spot welded and then the project got scraped and had to be rewrapped? Why would anyone go to the trouble of rewrapping OG cells otherwise?
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Possibly.
I mentioned a couple thoughts earlier…that they could have been bought without wraps or that they were early sample cells and needed to be rewrapped in something that looked like they were production cells.
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I have. The return and RMA stuff is standard fare, and there’s no mention of the sale of rewrapped, refurbished cells. All I saw that was relevant was this, on the product page:
Note the “fresh and genuine” remarks in bold caps.
Considering all the findings, it doesn’t seem that this squares up as it should for what was advertised on the product page.
