@Battery_Mooch do you have any (upcoming?) info on Samsung 50Gs?
Theyāve been around for over three years but 100% of the production is probably being instantly bought up and thereās no excess inventory to be sold off to make them available to us.
No performance data yet, just the basic specsā¦
4900mAh min capacity
9.8A continuous
14.7A non-continuous, temp-limited to 60Ā°C.
Like any ultra-high capacity cell theyāre probably best used at a decent level below their ratingā¦perhaps at 5A-7A or soā¦to avoid lots of voltage sag.
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Could anyone please help me with a 10s battery build? Iāve double checked all my connections and they seem correct, I measure 31V on the main + and - points but the power end of the BMS only reads 4V
My balance leads read:
Neg + 1. 4.16v
Neg + 2. 8.16v
Neg + 3 . 12.32v
ā¦ 4. 16.46v
ā¦ 5. 20.62v
ā¦ 6. 24.78v
ā¦ 7. 28.9v
ā¦ 8. 2.87v
ā¦ 9. 3.04v
ā¦ 10. 3.2v
Those last 3 are so wrong and idk why
Are those last 3 p-groups fucked? Should I put together 3 more p-groups?
if you take the multimeter and go between each s set instead of from pack neg and moving down the row
(so
pack neg + 1
then 1 2
2 3
3 4
so on so forth to the end it might give you a better idea
send a pic of your balance lead wiring setup as well?
The wiring is messy but Iāll try to do some mspaint to make it visible.
One moment please 
I realize what you mean and thatās already how I have the data displayed.
This is not a flex packā¦ soā¦ I donāt think it will see more rubbing then this. - YouTube
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h.265 rip
cant view the video
use this
Fixed
Wiring shouldnāt be messy. IMO check the packs individually. It looks like you either have bad wiring on your leads or torched the last three trying to solder to them. Most likely bad wiring.
you can check it through another method
instead of checking the āsumā of the s packs
you can check the voltage of each individual through the balance lead by going
neg 1
1 2
2 3
3 4
4 5
ā¦
10 pos
so move down the line but move both probes instead of one, see if the voltage goes wack
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I found it was b7 that is having an issue. DMM gets no measurement from the cells, I think I fucked them or they were already fucked or something. I guess Iāll weld up a new p-group.
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All right battery police. I need you to take a quick look and tell me if you see any issues here.
I had this battery made by @Acido so his usual stuff. Double fishpaoer between p groups, no welds at the center of negative pole. So that was top notch work.
But the battery came with 2x 12Awg wires between p groups. Unfortunately it is a bit too much in terms of hight for my taste to feel confortable.
I had a copper braid laying around so Iāve decided to go for it as a p group links.
I have weighted same length of stripped 12 awg wire and this copper braid, and the braid weight about 2% more. So I have assumed it can carry same if not higher current. But just in case I went with 3 links instead of 2.
Definitely saved some height.
Do you see any problems here? Iāll do balance wires today.
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Always check voltage on the leads before you plug it into the bmsā¦ this will save you many a bms
Looks good from a glanceā¦ I would have used tinned braided copper. You are good in terms of ampacity though.
P.S. beautiful build manā¦ you may have won this yearā¦ watch out for next 
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I personally would have tried to space the braids out more evenly along the tabs to avoid any high-current concentrations in the nickel as much as possible, but honestly this is more than fine as is. That would just be gilding the lily and nitpicking, for likely only a theoretical benefit.
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I donāt like braid for flex connections. Gives me the heeby jeebies.
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I get you. Why I did it this way is because I am planning to run all the balance wires on the left side of the pack. Thatās the only route that is possible due to things I have on the bottom side of the deck.
I have similar feeling. What I did to try to mitigate this issue is to compact braid at places where it will flex a bit. It is much more flexible this way. But to be honest flux deck doesnāt flex much if any under my weight. I am 79kg.
Why?
Can anyone help me with a pack not charging? DMM reads everything properly, but the pack is stuck at 33.9v on 2a charging for like 5 hours. 10s4p 35E