sailing boat with three AGM 140ah batteries.
Victron solar MPPT 30/100
Victron shunt
Victron DC DC charger.
Victron multiplus 12/60/1600
Batteries seem to behave normally till they reach 12.6 volts then voltage drops of to 10.5 v very quickly.
Yesterday when batteries were fully charged I applied a load of 15-20 ah Batteries behaved normally and voltage dropped off gradually
When I came in the morning batteries were 10.8 volts See chart below
Second chart is over a week Batteries seem to hold charge then just fall away to 10 volts in the middle of the night
