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
There is mixing dis-similar batteries and then there is mixing same type batteries but of different AH sizes. You can do both and "get away with it" if you take care to recharge them to full by individual type.
You can bank them all for maximum Puekert (two 100AHs in parallel is worth more than two, one at a time) while camping. Big thing is separate them after and do their recharges to each type's specs. Then you can bank them again and Float them all at once.
time2roll here, says each will take what it needs from the float charger and keep up. I have no measurements of that, but IMO he knows his stuff, so it should be ok. Assumes each needs the same Float voltage in its specs.
In my case with two different brand /type AGMs, they have different charging specs--14.8ish for the 100s and 14.4ish for the 250. but they have the same Float spec of about 13.8.
So that's easy, I camp with them banked as 450, get home and separate them to recharge each to full, then banks again to float. A wrinkle with these AGMs is that the recharge must be at over 20% charging rate. So even if they all had say 14.8v charging spec, I need enough amps to do the 20%, which would be a 90 amp charger. Only have a 75 amper.
So I split the bank for two reasons: the 75 on the 250 for over 20% and the 14.4 vs 14.8 thing.
Point being you have to do some work. This is not a fire and forget deal.
You can bank them all for maximum Puekert (two 100AHs in parallel is worth more than two, one at a time) while camping. Big thing is separate them after and do their recharges to each type's specs. Then you can bank them again and Float them all at once.
time2roll here, says each will take what it needs from the float charger and keep up. I have no measurements of that, but IMO he knows his stuff, so it should be ok. Assumes each needs the same Float voltage in its specs.
In my case with two different brand /type AGMs, they have different charging specs--14.8ish for the 100s and 14.4ish for the 250. but they have the same Float spec of about 13.8.
So that's easy, I camp with them banked as 450, get home and separate them to recharge each to full, then banks again to float. A wrinkle with these AGMs is that the recharge must be at over 20% charging rate. So even if they all had say 14.8v charging spec, I need enough amps to do the 20%, which would be a 90 amp charger. Only have a 75 amper.
So I split the bank for two reasons: the 75 on the 250 for over 20% and the 14.4 vs 14.8 thing.
Point being you have to do some work. This is not a fire and forget deal.
