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I'll copy my post from the other thread.
I'm running bottom balanced without a BMS. My SE/CALB cells range in capacity from 110ah-114ah. Four months after my initial bottom balance I checked again and they were all within less than 0.08 volts of each other. I rebalanced again with a more accurate meter so they were all within 0.004 volts of each other and I'll check them again in December. I've pulled 5.5C from the cells occasionally and had one low discharge event to an average of 1.77 volts per cell yet they've remained well balanced at the bottom. I do undercharge the cells to be safe. The PFC voltage trim is a bit less accurate than I had hoped. If I need a full charge I'll flip the charger back on for another 15-30 minutes while I monitor closely, but not very often. I like the safety bottom balancing gives me while driving in the event of low SOC but as long as you stay away from the top and bottom I think you can get away with top, bottom, or middle balancing, without a BMS. I do have an adjustable charger, PFC-30, so I can change current draw and cutoff voltage as temperature changes the resistance of the cells. If I did not have an adjustable charger and wasn't using a BMS I'd probably top balance the pack. I'm using Dimitri's EV Display for amp hour counting which makes life easier being able to see how much charge goes into and out of the pack.
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I would say right after the charge. Just curious if my math is the same as the real world. In other words, charging from 3V to 3.6V you may only have 3.58V in your 114 Ah cells since that would be a 3% difference in capacity.
No it doesn't work that way. If I charge my smallest cells to 3.6, which I rarely do, the largest cells will only get to around 3.45 or so. Voltage climbs much faster near end of charge so it's not linear at all.
After sitting for a while they all drop down to 3.336-3.338.
 

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I'd like to add the questions:

What is your max charging current?

What is your max regen current?
My max charging current is 38 battery amps at 120 battery volts from a 240V 30 amp circuit though not for long since the PFC 30 goes into overtemp limit and cuts back to around 36 amps. Charging 120VDC from 240VAC is not very efficient. Normally I charge around 25 battery amps.
Max regen I've seen is a little over 200 amps for a couple seconds, normally between 50 and 150 amps.
 
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