I didnât realize this. I just figured I was wrong about 18650s outputting 4.2 volts. 12s6p you think? Parallel cells wonât have any affect on the motor controller right? The just essentially increase the fuel tank (Im sorry for the noob questions, I never thought before looking here that Iâd be manufacturing my own battery lol)
The more cells in parallel the more current you can draw out of your pack and yes with the same serial count you also get more range with more parallel cells.
Basically in simple terms higher the series the higher volts of the pack the higher the parallels the high the amps you can draw from your pack.
So after discharging my battery to 38.5V the parralel groups are now at:
B1: 3.85V B2-10: 3.86V
It seems like it was just a balance issue and (hopefully) not a dead cell 
The question is now: Should I charge my battery with my old charger or new one?
If I decide to use my old charger, can I see if it was because my new charger is charging a bit too fast the packs didnât get balanced. If I decide to use my new charger, can I see if it will do the same thing again or what actually happend.
I prefer to using the old charger, only issue is that it will take about 8 hours to chargeâŚ
Any suggestions?
edit: Plugged my old 2A charger in and now itâs charging. B1 immediately reached 3.86V
I would continue charging with your new charger and monitor the individual pack voltage for the next charge cycles. If it will repeat to get slightly out of balance try it with your old charger. If it still get out of balance than there is something wrong
Thanks for the suggestion.
So after checking all of the voltages again B1 is 3.88-89V and B2-B10 is 3.9V. That seems a bit oddâŚ
Donât overthink that. All cells have minimal different internal resistance. Your bms doesnât balance now. Only after reached the balance limit which is like 4.2ish volt per cell. Thatâs totally normal that not all packs charge up 100% the same.
So after charging my board with my old 2A charger all parralel groups are now at 4.11V 
It seems like the problem is caused by the charger.
Well it is known that the low and slow approach to charging extends the life of your cells.
4A on a 4p pack is definitely not too much. Sure slow charge is good but this cells are made for regular slow charge of 1.5A. That would be 6A easy peasy on a 4p pack.
So after letting my pack charge fully it finally reached 42V. The weird thing is, that now B1 is at 4.17V again while B2-B10 is at 4.20V. The pack charged completely fine and balance but not at the end.
Donât know how it should be possible but it might be a BMS issue that the BMS thinks B1 is at 4.2V but itâs not really.
So itâs probably not a charger issue.
It could be:
- BMS issue
- Cell issue (dead cell etc)
edit: It could be fixed by setting the EOC to 41.5V (4.15V per cell) for both longer life span and the same voltage in each cell.
Did you check all your cells before making the pack? Maybe one cell was off with the voltage.
I wasnât saying it was to hi just that it is just generally better for extended life
Yes, checked all cells at the beginning. There was a max difference of 0.02-3V. Every cell was at about 3.44V and a few was at 3.43V and 3.45V. It could also be that.
Letâs say itâs because of that. I will probably never drain my battery below 33.5V so does it even matter? I mean as long as all of the cells are healthy.
Could anyone help a brother out with this wiring? Based off a recent post on this thread. The original post had xt60s after the xt90 powers, unsure of why the xt60s and xt90 powers had to be there.
You diagram is very confusing why do you have leads connecting the male and female together they connect right together. Is the battery 18560 batteryâs cause those would have balance lead going from the battery to the bms.
Oh yeah that is right. So the guy I am buying the battery from said:
âThe bms wires and balance leads are all in the blue shrinkwrapâ and âThe battery has two wires coming out of it, an xt 60 and the red 2 pin nub for the chargerâ
Not sure how to connect the battery with this info
The xt60 is where you connect the load, the small 2 pin is where you connect the charge port.