12 Volt AGM Batteries
The name 12 volt battery is a little misleading.
When a 12 volt AGM battery reads 12 volts it is nearly flat.
When taking a reading of the state of charge (SOC) of a battery it should be done when the battery is at rest ie when there is no charge coming in to or out of the battery, otherwise a false reading may be obtained.
The reading should also be taken a couple of hours after the battery has come to rest otherwise there may be some residual effect on the reading.
Please see a suggested state of charge chart for a typical AGM battery below.
Batteries like being charged or nearly fully charged – the more they are kept fully charged the longer they will last.
Even if a battery is taken down low only a few times it could have a detrimental effect on its life.
|Percent of full charge||12 Volt DC System|