I have purchased 4 - 12v 170AH BigBatteries and have them connected in series (24v) / parallel.
They don't seem to keep the balance between 12v batteries. When charging, one battery will hit ~13.6v and stop charging and the rest of the charge will go into the other battery at 15.3v (13.6+15.3=28.9v). Although the batteries display these charge values, the have stopped taking in a charge. I think one of the BMSs has shut down at the high voltage cutoff.
This happens when the charger tries to go from bulk to fixed voltage for absorb or float.
It doesn't matter what my charging source is. I have tried 2 different Magnum inverters, a victron solar charge controller, and the progressive industries charger.
When I separate the batteries from 24v series and configure them back into 12v parallel, they seem to charge and equalize fine.
I don't want to break the warranty seal to check each of the cells. I sent one back to big battery and their shipping department said it was fine, but they didn't test it as a series configuration.
Is there a way to keep these batteries in balance when configured in series?
Couple of pics of two 12v batteries connected in series. When reading the voltage on either the Victron MPPT controller or the Magnum ME-RC the voltage reads a combined 28.9, but it shows no amps going into the batteries.
They don't seem to keep the balance between 12v batteries. When charging, one battery will hit ~13.6v and stop charging and the rest of the charge will go into the other battery at 15.3v (13.6+15.3=28.9v). Although the batteries display these charge values, the have stopped taking in a charge. I think one of the BMSs has shut down at the high voltage cutoff.
This happens when the charger tries to go from bulk to fixed voltage for absorb or float.
It doesn't matter what my charging source is. I have tried 2 different Magnum inverters, a victron solar charge controller, and the progressive industries charger.
When I separate the batteries from 24v series and configure them back into 12v parallel, they seem to charge and equalize fine.
I don't want to break the warranty seal to check each of the cells. I sent one back to big battery and their shipping department said it was fine, but they didn't test it as a series configuration.
Is there a way to keep these batteries in balance when configured in series?
Couple of pics of two 12v batteries connected in series. When reading the voltage on either the Victron MPPT controller or the Magnum ME-RC the voltage reads a combined 28.9, but it shows no amps going into the batteries.
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