Originally Posted by KarenKamper
Does anyone know how long it generally takes the battery to gain full strength?
4-5 hours to do it right with a decent converter or the appropriate charger, but just a few hours to get to a 90% state of charge (SOC). That is the quick answer. But, that is the minimum time.
Batteries like to be charged slow and fully and then stayed charged, so its better to err on the side of charging longer than that. This is fine if you are doing it though your trailer's converter (assuming its a three-stage).
Read on if you want a little more...
The better answer is that it depends on the size of the battery, how run down it is, how much current is supplied from the converter/charger and how good that charger is - one-stage or three-stage.
So, for a small group 24 discharged to 50%, which you don't want to go below, its usually a few hours to get to 90% but then the amps drop way down and it will take several more hours to fully charge to a 100% SOC. This can be much longer with a bigger battery and much much longer with a trickle charger.