Multiple Batteries in Parallel
I have several regular 12v batteries that are different sizes. Can I safely hook them up in parallel without damaging any of them?
Forum Discussion
swimmer_spe wrote:BFL13 wrote:
Yes, but the main thing is they be in similar "condition", which means past usage and care of each one. Not good to bank a battery in poor condition with a good one, or you soon have two poor ones.
You can parallel different "size" batteries of similar condition, no problem. Eg an 80 AH with a 100 AH to get a 180 AH bank. They will draw down together (if balanced) so that at 50% one will be 40AH and the other 50 AH. They will recharge together and get to "full" at the same time also.
It is hard to balance several batteries in parallel. One way is to group them in smaller banks and then bank two groups. More wires but so what? With four batts you can make two pairs and then parallel the pairs. Then put your positive load/charge wire on one pair and the neg on the other pair.
That is what I was looking for. I have 2 batteries that are roughly in the same condition. However, their CCAs are about 100 and 200.
Don't know about CCAs! That could be a different story for how much each will do towards cranking. I was talking about Amp Hours and typical RV draws on house batteries, not for paralleling starting batteries.
Somebody who knows about that will have to jump in.
