I've just purchased a brand new Sterling 120ah lifepo4 battery and one cell seems to be quite severely unbalanced. On charging (14.4v as advised by battery data sheet) i have 3 cells at about 3.4 and one going over 3.75v which causes the BMS to cut off charging (see the attached). The difference between highest and lowest cell is 0.37v which is huge as far as my understanding goes.
I'm charging it with solar victron mppt 30a charger, set absorption at 14.6v (charging voltage from battery data sheet) and float at 13.8v as stated in the above data sheet. The victron profile for lifepo4 had slightly lower settings -14.2 absorption and 13.5 float which I also tried with the same outcome.
The charger never switches to absorption because at about 13.9V ( 3x3.4V +3.75v) the Bms disconnect the charging. After this the voltage gradually drops over couple of hours to 3.5v and n the unbalanced cell, then the Bms enables charging and the whole cycle repeats.
Is this a faulty cell and i should return the battery or is there something in the settings I'm missing?
I don't know if it matters but the battery has not been cycled at all. Came 92% charged from which it got changed to 100%-all reported by BMS so could not be very accurate.
Thanks in advance
I'm charging it with solar victron mppt 30a charger, set absorption at 14.6v (charging voltage from battery data sheet) and float at 13.8v as stated in the above data sheet. The victron profile for lifepo4 had slightly lower settings -14.2 absorption and 13.5 float which I also tried with the same outcome.
The charger never switches to absorption because at about 13.9V ( 3x3.4V +3.75v) the Bms disconnect the charging. After this the voltage gradually drops over couple of hours to 3.5v and n the unbalanced cell, then the Bms enables charging and the whole cycle repeats.
Is this a faulty cell and i should return the battery or is there something in the settings I'm missing?
I don't know if it matters but the battery has not been cycled at all. Came 92% charged from which it got changed to 100%-all reported by BMS so could not be very accurate.
Thanks in advance
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