agm battery charge issue
what would cause a AGM battery to reduce its charging amperage, without the voltage reaching the set voltage cutoff in a CC mode stage of a charger example, battery is at 13.6 yet a pd9245 in boost...
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It is normal for the battery voltage to rise during the absorption stage while amps taper. This occurs at different SOCs depending on the charging rate. You could be seeing the Absorption Stage starting earlier than you expected.
If the charging rate is with high amps you can have voltage drop between charger and battery so the battery voltage is lower than the charger's. As amps taper this difference in voltage becomes less as battery voltage rises.
Some PDs are not very good at constant amps in the Bulk Stage for whatever reason (Salvo used to complain about that with graphs to show it---however one guy here showed his graph where his did constant amps ok)
And as you note, with chargers it is loads first battery gets what amps are left over, so you might have had a load come on for a while that you were not aware of.
Not likely anything wrong with the AGM without more evidence IMO.
If the charging rate is with high amps you can have voltage drop between charger and battery so the battery voltage is lower than the charger's. As amps taper this difference in voltage becomes less as battery voltage rises.
Some PDs are not very good at constant amps in the Bulk Stage for whatever reason (Salvo used to complain about that with graphs to show it---however one guy here showed his graph where his did constant amps ok)
And as you note, with chargers it is loads first battery gets what amps are left over, so you might have had a load come on for a while that you were not aware of.
Not likely anything wrong with the AGM without more evidence IMO.
