Thinking of ohms law I don’t see how can have a voltage but no current.
The current is not zero, but extremely small.
A multimeter on voltage test is typically like 10MΩ or more
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So the blue circles on the negatives of these cells show if the cell is good or not? That’s actually kinda cool.
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Wouldn’t the voltage match the current that would be produced? If there was an added large resistance in series with the cell wouldnt a matching drop in voltage also happen as with ohm’s law?
The blue turned to yellow looks to be a valve release or a safety mechanism of some sort. I didn’t hear gas released though and the cell barely had time to get even warm but the surface cracked as if to release gas. I’ll write them and ask what’s what and didn’t see an explanation of the cell design on their site
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Hey guys! I made a disassembly thread for anyone who wants to buy some of these cells
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Thank you! I was actually doing the same thing last night and after some other attempts came up with the same methodology as you!
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I understand they are cheap and relatively safe put out decent grunt but they are pretty heavy and as a lot of ebike guys can attest buying from the usual scum bags online can bring mixed results.
The weight put me off the most.
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It’s LiFePO4. 
There are many benefits, but weight isn’t one of them.
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Yeah if you ignore weight and size, the punch for the price is pretty significant. Range is like 8/10
I would trust the EMC packs overall, having such a constant / consistent loading should produce the expected results that battery clearing house claims I would think
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Agreed.
I would just not recommend these particular packs due to the unpacking work…
It wasn’t awful, I’ve done worse ones than these. The box of 10 took me and a friend about 1hr 15 minutes to harvest the cells
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I kind of like the unpacking. Makes me feel like I earned my salvaged cells!
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Haha yeah we lost 12/80 to pinholes in the positive end sadly, some of the welds were stuck on too well
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On that video: https://youtu.be/3jPYyGjWqck?t=627, the dismantler leaves the nickel strip on, just cut short and tidied up in place. Unless there is an absolute need to get down to the cell itself, that’s possibly the safest option.
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Yeah, depends on what you’re after. If you’re just looking to use salvage cells to build a pack, why disassemble beyond what you need to? Leave the strips welded and weld over it. If you’re looking to practice building packs, or the thing is real trashy, it might make sense to pull them all the way down.
I heard the release valve is on the positive side, which looks more like the negative side with these cells, and when it opens it’s just a crack you wouldn’t even notice unless you knew where to look
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I have one that’s opened like that, it wasn’t super noticeable
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We know for sure there’s no way to repair the pinholes right? Like you can’t just solder over it?
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I had no pinholes that I could spot after packs were taken apart. After a couple days with a hole the cell would show a low voltage or what?
These are exciting: https://batteryhookup.com/products/100-brand-new-lifep04-32650-3-2v-6000mah-cells?rfsn=1727885.2bd9ce&variant=35194643120290
6amphour is a lot for the size. “DIY” discount code gets u 10% off
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