Determining AH rating of aging batteries
My Trojan 125's are almost 5 years old now, when they were new they were rated at 240 Ah. Now my trimetric is showing 70% at 12.1 volts which I know is wrong. So how can I determine the true Ah rati...
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Screw all the other tests.
Fully charge at 15.0V at around 77F.
Equalize charge at 16.0 V until the Specific Gravity on all cells gets to 1.280, or the voltage at the battery terminals reaches 16.0V, then shut the manual charger off. Your manual charger is capable of a full 16.0V, isn't it? If not, get something around 10-15 amps that is capable of a full 16.0V
Log the SG of every cell on every battery.
Don't assume on the voltage being recharged with, measure it with a digital multi meter.
Don't assume on the specific Gravity, measure it with a Freas #1 hydrometer, with temperature correction.
Report the results here.
Then do what you need to do to recalibrate your trimetric.
Fully charge at 15.0V at around 77F.
Equalize charge at 16.0 V until the Specific Gravity on all cells gets to 1.280, or the voltage at the battery terminals reaches 16.0V, then shut the manual charger off. Your manual charger is capable of a full 16.0V, isn't it? If not, get something around 10-15 amps that is capable of a full 16.0V
Log the SG of every cell on every battery.
Don't assume on the voltage being recharged with, measure it with a digital multi meter.
Don't assume on the specific Gravity, measure it with a Freas #1 hydrometer, with temperature correction.
Report the results here.
Then do what you need to do to recalibrate your trimetric.
