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The BMS uses 24ohm resistors, so at 3.7v it will shunt about... 0.56watts

It splits the pack into groups of 6, picks the highest one (you can set a lower limit so it ignores the ones that are already low) and starts discharging. (this means discharge time will need to be multiplied by 6)

So, how much power are we talking about? Here the math gets a little fuzzy... Assuming the modules are 3kwh nominal - and that discharging from 4v down to 3v is 90% of the capacity, 1 volt would be (3000*.9) = 2700wh. Assuming a linear discharge curve, 0.035v would be 95.5wh - which is lot. At 0.56w, that would be about 172 hours... per cell. So do that 6 times and you are looking at 1032 hours, or about 43 days. I tried to be generous with my assumptions, so it could be a decent bit less.

Soooo, I had a thought. Part of the reason I bought these modules is that they are a good match to my off-grid stuff - so I am going to wire a little 300watt inverter through a power meter and then connect it to each high module one at a time. Running a 300watt load should bring the voltage down in about 20 minutes if my numbers are close. If I make sure to draw the same number of watt-hours from each module, the BMS should be able to handle the rest in a couple days.