I See Electromagnetic Fields!
- Mar 28, 2020
I will write a much more detailed reply later when I have the time. Daly has some bad defaults for voltage settings (3.75 and 2.1) that you really should change before you use your new cells and BMS too much.
Short term, you just want to change the default protection values, but just don't overcharge or over discharge the battery until you do.
OP - do you know what maximum voltage your charge controller charges to, and what minimum voltage your inverter discharges to before disconnecting?
BMS is meant to be your last-ditch protection mechanism to save battery from damage. Settings of 3.65V and 2.5V would be good for that. The defaults of 3.75V and 2.1V are pushing it too far, more chance of damage (and vanishingly small additional amp-hours made available with those wider voltage settings.) You should adjust BMS settings ASAP for your new battery and for the new BMS you're putting on the old cells.
Your charge controller and inverter should stop/disconnect at even tighter limits. It is best they never try to reach the point where BMS disconnects. Sometimes you have to figure out how to reset BMS if that happens. Maybe something like 3.35V charge and 2.8V (per cell) discharge would be good? The other guys can better recommend settings. It seems likely (from your 13.45V measurement) that the charge controller already does that. But lots of inverters discharge too low, so see if its low-voltage cutout is adjustable.