# and Type of house batteries
I have a 2019 Jayco 22' C Class. is it better to have one group 27 battery or two group 24s?
Forum Discussion
Acid boil-over from over-charging is unlikely with a converter/charger with its voltage limited as it is.
A "manual charger" that needs to be shut off by the operator once the battery voltage reaches the desired level could do that if not being watched. The battery voltage keeps on rising into the 16v range or so. But not a converter.
Perhaps what happened there is a battery had a bad cell.
You can parallel two 12s with different AH "sizes" with no problem if they are both in similar condition.(not with a bad cell in one of them) Eg, a 120AH and an 80AH to get a bank of 200AH. Draw them down and at 50% one will be at 60 and the other at 40. They will recharge together reaching 120 and 80 again at the same time. No problem.
Even with good batteries of course you must keep the electrolyte level below the caps so when being recharged and getting warmer from that, there is room under the cap for the expansion, or they will run over.
A "manual charger" that needs to be shut off by the operator once the battery voltage reaches the desired level could do that if not being watched. The battery voltage keeps on rising into the 16v range or so. But not a converter.
Perhaps what happened there is a battery had a bad cell.
You can parallel two 12s with different AH "sizes" with no problem if they are both in similar condition.(not with a bad cell in one of them) Eg, a 120AH and an 80AH to get a bank of 200AH. Draw them down and at 50% one will be at 60 and the other at 40. They will recharge together reaching 120 and 80 again at the same time. No problem.
Even with good batteries of course you must keep the electrolyte level below the caps so when being recharged and getting warmer from that, there is room under the cap for the expansion, or they will run over.
