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my first build 14s80p; cell capacities
#1
Hi Everyone. 
I am most of the way through collecting cells, ready for my first build of a 14s80p battery. The range of cells I have collected goes from 1600mAh through to 2400mAh. Could I ask whether I would better off discarding the lower capacity cells and narrowing the capacity range, or could I mix the cell capacities up into broadly equal packs with a mixed grouping of cells from the lower through to the higher ranges. I would appreciate some guidance.
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#2
It depends



If the original capacity of the 1600mAh cells was 2000mAh, then you're probably ok to use them. If they were 2400mAh, don't put them in high power applications. They are close to EOL.

Now the biggest thing you want to make sure of is that all 14 sections of parallel needs to be as close to each other as possible. So, for example, if you have 1 pack that is 25Ah, and the other is 24Ah and you have a cell you can swap between them to make them both 23.5Ah, do it. The closer the packs are to the same capacity now, the better chance you'll have a better success rate of keeping them balanced with a proper bms
Proceed with caution. Knowledge is Power! Literally! Cool 
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#3
(06-29-2020, 12:28 PM)Korishan Wrote: It depends



If the original capacity of the 1600mAh cells was 2000mAh, then you're probably ok to use them. If they were 2400mAh, don't put them in high power applications. They are close to EOL.

Now the biggest thing you want to make sure of is that all 14 sections of parallel needs to be as close to each other as possible. So, for example, if you have 1 pack that is 25Ah, and the other is 24Ah and you have a cell you can swap between them to make them both 23.5Ah, do it. The closer the packs are to the same capacity now, the better chance you'll have a better success rate of keeping them balanced with a proper bms
Thanks Korishan, much appreciated. I will look through the cell databases and establish what the original capacity was for each cell instead of just relying on what the current tested capacity is. Dave
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