MEXICOWANDERER wrote:
Sure as Hell, CONSTANT CURRENT CHARGING will hurt a battery. Constant current is only done under meticulously supervised conditions to rectify damage caused by an incorrectly applied recharging period in which the batteries are abused by undercharging. To wit...
Read the LIFELINE manual about RECOVERY
Maybe we are all speaking different terminology but right from the Lifeline tech manual on charging:
The recommended method of charging Lifeline® AGM batteries is to use a 3 stage charging
profile. In the first stage, a constant current is applied until the voltage reaches a pre-set limit.
The first stage is often called the Bulk charging stage.
In the second stage, the voltage is held constant at the same pre-set limit until the charging
current tapers to a very low value, at which point the battery is fully charged. The second stage
is often called the Absorption charging stage. A voltage setting of 14.3 volts ± 0.1 volts (7.15 ±
0.05 volt for a 6 volt battery) should be used when the battery temperature is 77°F (25°C). The
battery is considered to be fully charged when the current drops below 0.5% of the battery’s
rated capacity (0.5A for a 100Ah battery). The absorption stage will typically last 2 – 4 hours
before the current reaches this level.
In the third stage, the charging voltage is reduced to a lower value that minimizes the amount of
overcharge, while maintaining the battery at 100% state of charge. This third stage is often
called the Float charging stage. A float voltage of 13.3 ± 0.1 volts (6.65 ± 0.05 volts for a 6 volt
battery) should be used when the battery temperature is 77°F (25°C).
My Magnum does this and I posted previously a charging test showing amp and volts from 49% to float:
Time Inverter-V BMK-V BMK-Ah BMK-SOC Inverter-A BMK-A BMK-T
9:50am 12.5v 12.70v -5Ah 97%
7:35pm 12.2v 12.32v -113Ah 49%
7:37pm 13.5v 13.44v -110Ah 50% 125A 104.0A 77F Bulk
7:52pm 13.8v 13.79v -87Ah 60% 125A 105.6A 82F
8:00pm 14.1v 14.08v -73Ah 67% 125A 105.2A 86F Absorb
8:04pm 14.1v 14.14v -66Ah 70% 111A 95.8A 88F
8:12pm 14.1v 14.18v -55Ah 75% 85A 77.2A 88F
8:22pm 14.1v 14.20v -44Ah 80% 70A 60.8A 88F
8:34pm 14.1v 14.22v -34Ah 85% 51A 45.8A 86F
9:06pm 14.2v 14.32v -15Ah 93% 30A 25.8A 84F
9:25pm 14.2v 14.36v -8Ah 96% 20A 17.2A 82F
9:45pm 14.2v 14.34v -4Ah 98% 15A 11.2A 82F
10:23pm Float
Every multistage charger I have seen does this, bulk is constant current, putting out the max current of the charger or some lower setting if trying to limit draw, the voltage slowly rises until the absorb voltage setting is hit, then it switches to constant voltage until time or amps or soc is reached depending on charger and settings, my Magnum can do any of those.
