Hmmm thats kinda sad 
but thanks for your explanation!
Nicely explained.
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nkon had the 40Ts on 3.95ā¬ bulk for some months now, nothing really new.
Iāve been quite happy with my LG M50LT purchase, at 3.99ā¬ / 3.45ā¬ bulk they are a steal as well.
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Iām going to measure all my parallel groups to see if the voltages are all the same. And Iām pretty scared to get any shortage 
could someone pls tell me whatās the best way.
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From the balance harness. Start on B- and measure each lead progressivley recording the voltages. Then you can figure out the voltages of each cell by the difference.
Do it from this part of the harness:
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Thx 
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So I measured the groups. 3 of them are 4.2V so fully charged and the other 7 are just 4.1V. Is that problematic or not? 
Ya thatās problematic. Thatās most likely broken welds on those two groups if they were in balance at the start of the charge cycle.
Youāre absolutely certain all the groups were balanced before the charge?
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Also, where did u purchase your cells?
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Yeah all groups had the same voltage when starting. I measured all batteries on 3.6V. Because Iām using NESE it canāt be a bad weld I guessā¦ group 3/7/10 had the voltage of 4.2V.
NKON.
As u have several groups that are charging much faster than the others, its more-than-likely that those groups are not properly connected in paralell. This would account for the difference in capacity. Itās also possible that u have faulty cells but I think you should first go back and make sure all of your groups donāt have any bad connections.
I have no experience w NESE so Iām not sure what the margin for user error is but thatās where u start.
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Aah alright thanks for your responses. Could it also be the reason because I used the battery for testing and didnāt charged it afterwards a while ago?
Edit: also my charger doesnāt really go to 42V after I checked output voltage is 41.7V
This is done on purpose so you donāt try to put braking regen into a full battery at the beginning of a ride.
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Oooh smart. Yeah Iām bypassing it so wouldnāt bother for me but if youāre not thatās great so I did some calculations and i think those differences in voltage could be occurred by the results of my multi meter being not exact enoughā¦ ? When I measured in 2 decimals the 3rd group is just alright. Canāt still explain then why it isnāt charging to 41.6 and stops at 41.3
Couldnāt it just be the cells being somewhat mismatched in IR/capacity since itās the first charge? Also, 4.1 V vs 4.2 V with no more significant figures could be a tiny difference technically. Unless you run the battery down some and the difference gets worse I would guess the pack just needs time to balance out a little.
Unlikely. Legit cells that are new, close in age and from a reputable manufacturer should all be very close in IR and capacity. It follows that if they all start at the same voltage they should charge and discharge in a relatively uniform manner. If they donāt, something is wrong.
Youāre technically correct but my guess is that an overvoltage cuttoff happened during charge w one of those higher cells. This stops the charge. Itās caused by a significant difference in the capacity of one of the groups and is often the result of broken welds but also sometimes faulty cells. In my experience, the former is far more often the culprit.
Iām here to admit some failures and ask for help.
Iāve built 2x flat pack 12s4p batteries, trying without success to make them esk8 proof
I have all the cells still from both packs, though because of popped welds some groups/cells are NFG
got my strapping tape and kapton game on lock as far as this thread is concerned.
got a maletrics on an XT90 with a Zeee 3s 9Ah 100C LiPo on it. Considering a 2nd LiPo but idk how an XT90 parallel adapter would faire, considering how hot the wires get after only a few welds and I donāt think I have the means to solder this 10AWG into the QS8 it should probably be using (battery has an EC3 to XT90 on it).
using one of those printed handles with the switch in it that holds probes together.
have been trying everything from 20ms-50ms. welds are really inconsistent, to the point of blowing through nickel or barely welding at all.
as for technique, I press down hard, let the spring relax and then the weld happens.
it seems some or most welds are really good on one side, but really light on the other probe.
Iāll bet my left nut its the probe holder thatās fucking you up. Those things are garbage.
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