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1/2 hour and then going on a 15 minute drive as well
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That's not going to put much energy in battery. In the best case scenario if there is say 20A going in the battery with 90% efficiency 45 minutes it will only put 13.5Ah which will be 13.5% on the 100Ah battery.
To charge battery from totally flat you are looking at 10hrs with powerful 10A+ charger to get it to 80% or 20hrs with 5A charger. Last 20 % need to be charged at lower rate with 2A or less and most smart chargers limit current to 0.8A and efficiency is lower when battery gets fuller so to go from 80% to full will be another 25-30 hrs but you can leave it 80%, no need to get it to 100%
Battery might have suffered as well if it has run nearly empty several times or remained nearly empty for long periods of time.