I just purchased a 2019 Entegra 31V. Alhough there is room for 2 coach batteries there is only one Harris Deep Cycle RC 150 installed. I tried locally to get one like it, but with no luck. Does a second battery have to somehow "match" the other?<br/><br/>Also I realize the onboard geneator provides AC when no hookup is available, but I am not wild about lestening to it run....