The other thing you can do when not camping is keep the battery plugged into a trickle charger / battery tender.
I keep my trailer plugged into 15 amp shore power at home all summer long when not in use. The onboard charger is not good and will boil the battery if left charging for too long. I remove the onboard charger fuses and then plug a trickle charger into the 12 volt plug near the TV. Then I plug the power supply of the trickle charger into a 120 volt wall plug. It maintains my battery without compromising it while the trailer is not in use.
While camping I only use the onboard charger when the trickle charger can not keep up (that does not happen often)