# 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
On recharging, a battery with a bad cell will take more than its share of the current so the other good batteries in parallel are short-changed. So that cannot mean the good battery gets over-charged and spills over. In fact it does not even get full.
Something else must have been going on to make them both spill over. "Overcharging" means battery voltage has gone too high and you will get spill over from the caps (or venting with a sealed battery)
I wonder if the converter in the rig that had the two 12s (twice) had something wrong with it so its voltage went high.
Good that you have solved the problem since then. I just don't think it was from having 12s in parallel as such that was the problem.
Something else must have been going on to make them both spill over. "Overcharging" means battery voltage has gone too high and you will get spill over from the caps (or venting with a sealed battery)
I wonder if the converter in the rig that had the two 12s (twice) had something wrong with it so its voltage went high.
Good that you have solved the problem since then. I just don't think it was from having 12s in parallel as such that was the problem.
