Recently I have experienced a problem where the charger is not fully charging a 100Ah, LiFePO4 battery.
I drained the battery to around 50% SOC and then started the charging process. The charger immediately goes into Absorbtion mode and after a period of time, into storage mode. The battery monitor tells me that the battery is not fully charged. The charger is however still putting 1.2Ah into the battery.
I restart the charging and after 2 hours, the charger again goes into storage mode whilst still putting a small continuous current into the battery for 14 hours before the battery actually reaches 100% SOC.
It’s a 30A charger and was charging a 100Ah LiFePO4 battery. I’ve had the charger for a few years and not had this issue before.
My other issue is that despite the battery being at 50% SOC, the charger did not bulk charge and went straight to absorbtion - which seems strange to me given the SOC.
OK, what I think is happening now I know it is a 30A charger is you have developed a high resistance on the cables between the charger and the battery so you are getting voltage drop, the battery was probable at 13.7V but the charger terminals at 14.2V which restricted current. This is why it skipped bulk.
Check all your connections are tight, fuses and breakers / isolators are tight, both on positive and negative. You can use a multimeter to find at what point the voltage changes.
Do you have resettable breakers, these are not very good and often degrade giving high resistance.
