4.3 wide by 14 long by .5 tall. This could be made to fit under a few decks for sure in 12s1p configuration, although I am mainly thinking about my bioboards deck
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The lg cells? A bit too expensive for me 
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The most often used end-of-life point Iāve seen is 80%. A few cells use 60% of the original capacity as end-of-life though.
Along with capacity loss you typically also get an increase in the internal resistance (IR) and, possibly, internal damage and lithium dendrite growth. The IR increase causes additional internal heating and IMO should result in the current rating being lowered. The possible damage and dendrite growth increases the risk of using the cell and are also good reasons for lowering the stress the cell would experience during charge and discharge (by lowering the charge and discharge ratings).
Thereās no way to know how long those cells would last without a lot of testing. It might be 50 cycles before the capacity really starts to plummet, it might be hundreds.
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Right on, my thoughts were along the same lines. Thanks for the additional info.
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Looks like the LG batteries are sold out. Would be pretty interesting to see a board with new ones in a 12s1p configuration.
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look at this $75 premade 20S ebike pack!
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arenāt those usually for lawnmowers ? xD would be somewhat hard to fit one in the frame tho maybe with side mounts on the rear wheel?
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Those cells have been sold out for months. Thereās other high drain ones that r selling in packs of 12 with similar properties. I got a couple for a 24S gokart
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Theyāre always claimed to be the same as the tesla cells. Pics look close but not quite.
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They could be anything. The image of the bottom of the cell is out of focus so you canāt tell if the three āstripesā (short lines) in the middle of the cell are there that the Tesla cells would have. That mark looks a lot more blob-like than lines.
The āHigh Gradeā claim is preposterous. They have absolutely no idea what the grade of those cells really is.
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I think tesla cells, that marking dead in the middle on the negative side, and even the top electrode looks alot like the last batch of tesla cells I got.
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I have the BCH site owners personal cell number so should I ask for more pics?? hahaha
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Actuallyā¦.
An in-focus shot of the bottom (so we can see the three lines) and of the top without the wrap and insulator ring (so we can see the spot-welded top contact) would help a lot towards showing that these were Tesla Model 3 cells.
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Yeah Iām pretty sure these are the same basic cells as everyone else was selling as Model 3 cells.
I know BCH is in the process of a warehouse move so they may be unresponsive.
I did buy a large chunk of A123 Lifepo4 cells in those EMC packs from them, they treated me very well, and when I inquired about the capacity of these and other salvage cells they had, they were upfront and honest about it. No clue about these 2170s but Iāll definitely be buying many many more kWh of the a123 cells from them for my cabin powerwall.
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As Mooch said, itās generally 80%, and thatās a long hold over from previous tech, not specific to lithium.
Unfortunately, thereās almost zero serious long term cycle life study done for degradation characteristics below 80% for almost any chemistry, and one thing that most arenāt aware of, is that very minor changes in chemistry and configuration can have a huge effect on this.
Some cells have a steep drop off below the cycle life thatās given to that 80% EOL, some, degrade at a pretty consistent pace, and some even slower than the initial rate to 80% OAC.
Thereās been some speculation that Tesla tweaked chemistry and config specifically for this with their nickel cobalt chem, without switching to a less energy dense chemistry with higher general cycle characteristics like LiFePo chems, which is why used Teslas even with high mileage show little loss of overall range, which would be smart, as concerns of long term range loss were one of the big criticisms being lobbed at them in earlier days.
That said, I would greatly favor lifepo4 chems for salvage cells if you want any longevity. What limited legitimate studies Iāve been able to dig up (and please nobody reference that batteryuniversity bullshit, itās just that), show lifepo4 as generally having much better degradation characteristics and overall cycle life beyond the 2000-4000 general cycles (vs 600-1000 average for most nickel cobalt chems from what Iāve seen) to 80% of original capacity. Some seemingly following a very slow decline potentially in excess of 20k cycles before being ādeadā, although Iām sure by that time youāll have plenty of random cells that simply decide theyāre gonna quit. At least with Lifepo4 you have significantly lowered risk of fire or other dramatic event, and the charge/discharge rates are generally an order of magnitude higher already so youāve got latitude to adjust without much inconvenience.
Unfortunately, obviously, energy density doesnāt make them ideal for esk8 applications where range is a factor.
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I am currently riding around some of those $1 cells around and they are performing like new! awesome stuff the expectations are always beat by them.
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This isā¦ VERY temptingā¦ Would you guys actually consider leaving the cells in the enclosures or taking them out and making a new battery?
Iām worried about how difficult it would be to take the existing nickel strip off of the batteries.
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Ohh the pack is a 20s5p inside already it seems. I would want to take it apart and go 13s7p or something more reasonable
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