Van battery question

[sternwake]

without a hydrometer or an Ah counter, to determine full, one needs an Ammeter, and a charging source capable of holding the battery at absorption voltage. When Amps taper to 0.5% of capacity on AGM, at absorption voltage, NOT float voltage, then it can be considered full.

Maintenance free flooded are similar, but absorption should be 15 ams amps should taper to near zero.

If amps have stopped tapering at absorption voltage, and start rising, the battery is full

Ammeters are cheap, and a charging source capable of holding 14.4v+ for as long as required need not be a huge investment either, if one has some DIY ability