I’m thinking this as well.
I believe I have a few plastic spudgers around, I’ll give it a try. If it doesn’t come off however, could I try using something like a sanding wheel on a dremel and a vacuum to pick up the metal dust?
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If I had to deal with this I would try a flush wire cutter or small pliers before breaking out the metal-dust-creating power tools. If the debris splattered on then it shouldn’t be too hard to get off manually.
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I made this spacers so my double stacked 21700 cells are just high enough to fit in a DS 18650 enclosure. I hope I didn’t just print 53 of these for no reason 
Why the spacers though? Is the airgap bad?
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I need the cells to be separated just 5mm beween each other to use up all horizontal space available.
By doing this, my double stacked cells will be a few mm lower than a regular double stacked 21700 battery. So it will fit in a 18650 enclosure. I will send a pic when they’re finished!
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Thank you @MysticalDork @BenjaminF @Evwan @glyphiks for your help 2 days ago 🫂 it appears my battery is okay? Been charging at 1A for several hours.
While the voltages look good, should I be worried that damage may have happened to the cells? Like could they be more leaky / drain faster or have less capacity now?
How many volts per cell were u down to?
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I did not measure each S group till I plugged in my BMS because my battery is all sealed up with silicone, BMS above deck. At the very beginning I measured total which was 40.2V meaning 2.51V per cell, 16S. Once I connected the BMS at 49V, the 3rd group was really far behind but this one S group has always been different. Idk why.
2.51v per cell is perfectly fine. Probably no damage as most cells are rated to go that low anyways. That rogue group is concerning.
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Phew. Here is a reading from when I first made the pack. This third group has always been an outlier. It drains first and accepts charge the most first.
If i were you i’d bring the whole pack back up to voltage and closely monitor for a fee cycles afterwards.
Cell 3 looks like it may not have survived the ordeal.
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Would indicate that it likely has a dead cell in it
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Omg! I had a dead cell this whole time! I’ve put 100km on the board! That makes sense.
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Loose nickel can also show those same charge/discharge characteristics
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Haha packs in a lot worse condition have been run for a lot longer.
Record the behaviour of the pack over a few cycles, but i’m tipping something is definitely wrong with cell 3. Mightnot be a dead cell, could also be bad weld/connection
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I have no idea about the welds. All I did was measure the cells when I first received them from delivery and they were all like 3.71+/-0.02V. They were all welded with a k-weld by @Common_good
I would guess the problem would be the cells because they are used cells? I believe @jack.luis also has Model 3 cells in his Cyboard. Any quirks with those? 
I got mine from BigBattery. I ordered 200 cells and one came defective at 0.30V or something for which they refunded me. But all the others were at 3.71V-ish. I’m just trying to provide as much info as I can here. Idk much about batteries and cells 
I have tm3 cells in 2 of my packs. They all stay perfect. There’s defo something up with that p group independent of this ordeal
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Yeah tbh i have no experience with those cells, but from most reports i can remember they seem to be pretty robust.
Before opening and inspecting, i would definitely recommend running the battery safely for a few cycles and observing the behaviour.
Start from a full voltage balanced pack, drain it a decent amount, rinse/repeat
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The ones in the cyboard are from a really long time ago when this cell was brand new on the market and was being sold for $2.50 a cell brand new.
Very different than ones being sold now
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To add onto that, they didn’t discharge down that low due to severe loading either, so it’s not like they sagged lower.
I too think they will be fine, good thing you caught it when you did though
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