adding a 12 volt battery to a bank of 4 =6volt battery

[Rmcgrath53]

I have 4 new 6 volt batteries and a 12 volt battery that is like brand new. Can I add this marine battery to my bank of four batteries?.
I have a solar set up of 560 watts with a mtpp Morningstar 60
Thanks for the help

[RJsfishin]

They are all lead acid batts, the chemistry is the same.
And did you and several others even read his post where he said it was an almost new "marine" battery ? READ HIS QUESTION !!

NinerBikes wrote:
Mixing different battery construction types, golf cart batteries, with a car battery, with different chemistries and amp hours per battery, is a lot like pairing a Honda Eu2000i to a Honda Eu1000i, to run something with a heavy amp load, like a 13.5k AC.

It can be done, but no one recommends it, and you probably shouldn't do it.

[NinerBikes]

Mixing different battery construction types, golf cart batteries, with a car battery, with different chemistries and amp hours per battery, is a lot like pairing a Honda Eu2000i to a Honda Eu1000i, to run something with a heavy amp load, like a 13.5k AC.

It can be done, but no one recommends it, and you probably shouldn't do it.

[2oldman]

RJsfishin wrote:
That is really sad when you have only 1 correct answer (above) out of all these !!

Getting answers on here is no different from hanging out with your buddies at the local coffee shop.

[westend]

Rich,
Thanks for your observations but I think everybody that posted is trying to be helpful.

I guess (maybe correctly) that the answer is yes, you can but is it going to work in your favor to do so.

[diveman52]

dougrainer wrote:
"I have 4 new 6 volt batteries and a 12 volt battery that is like brand new"

NO. You can NEVER add any older battery to a new battery bank and expect the system to function at its optimal level. You cannot add a 12 volt to a 6 volt(producing 12 volts) type system and expect it to function correctly in the long run. 12 volt and 6 volt batteries have different charging design parameters. Doug

X-2

[dougrainer]

RJsfishin wrote:

wa8yxm wrote:
You need to re-think and then ask the question of yourself again.

You said "I have 4 six volt batteries"

No, you do not

You have two two piece 12 volt batteries.

Now, The quesiton becomes

I have 2 12 volt batteries in parallel, Can I add a 3rd, and the answer is: YES

That is really sad when you have only 1 correct answer (above) out of all these !!

Yes, in the REAL sense, you CAN add a 12 volt to a 6 volt bank. BUT, as I pointed out, it will NOT function correctly and at its optimum performance. Doug

[RJsfishin]

wa8yxm wrote:
You need to re-think and then ask the question of yourself again.

You said "I have 4 six volt batteries"

No, you do not

You have two two piece 12 volt batteries.

Now, The quesiton becomes

I have 2 12 volt batteries in parallel, Can I add a 3rd, and the answer is: YES

That is really sad when you have only 1 correct answer (above) out of all these !!

[Rmcgrath53]

Thanks for the response. I am going to keep that battery, the 12 volt with jumper cable, and make use of it when needed.

[MEXICOWANDERER]

I would be sorely tempted to wire in a smart solenoid and use the car battery for outside lighting. Like an awning rope light. This keeps the Hatfield Boy from Getting frisky with the McCoy lass. It isn't at the dinner table or out squirrel hunting that the feud would ignite; it's when they were together with "nothing going on" that starts WW III

The old Trojan car jar RV battery had a higher antimony level and would survive longest with the 5% crowd. I don't know about now.

[BFL13]

Say you are a heavy AH user and going out for four days and you will need to do a "50-90" on the second day

You have 460AH in the four sixes and by the second day you are at 50%. But now you can only recharge to 90%, so for the second set of two days you are short 10% going in, because on the first set you started from full, not from 90.

After doing the 50-90, you decide you don't want to drop to 40% the next set, so now add the spare 12 with the jumper cables. This is like having that 10% back. 10% of 460AH is 46AH and 50% of the 100AH 12v is 50AH.

[MEXICOWANDERER]

Lesee, 5% antimony batteries on one side, 2% antimony on the other PROBABLY with a 1.5% calcium negative plate.

Mmmmmm

Chocolate covered Brussels Sprouts.


Bet'cha a person COULD eat it...

[wa8yxm]

You need to re-think and then ask the question of yourself again.

You said "I have 4 six volt batteries"

No, you do not

You have two two piece 12 volt batteries.

Now, The quesiton becomes

I have 2 12 volt batteries in parallel, Can I add a 3rd, and the answer is: YES

[2oldman]

These discussions may help..

Add 12v to 2 6v
12 and 2 6v 2010

[BFL13]

You can get value from the spare 12 by paralleling it to your "big 12" 4-sixes temporarily using jumper cables. That will give you some extra AHs when needed for some reason. I have done this many times.

Normally charge the single 12v separately from the four 6s, but if this is impossible, and you are charging the 6s, leave the jumper cables on and the 12v will get some charge too.

I used to carry the extra 12v in the back of the truck and charged it with an extension adapter I made up for the 7-pin so it got charged some (not much really, but every bit helps) while we drove around sight-seeing or going to town.

With that much solar, if you get to near full on the 6s in early afternoon, you can swap the solar over to the 12v for the rest of the day using jumper cables.

It all works, as long as you don't mind managing and keeping track of it all so it doesn't cut into the camping fun any.