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Lead acid batteries 6v vs 12v and mixing

Chip

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Jun 26, 2021
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OK I am looking to get batteries. found some 1100 cc 950cca 6v industrial tractor batteries for $50 each or 1050cc 750 cca 12v marine for $75
What is better the 6v or 12v and can you mix batteries like four 6v and two 12v running a 24 volt system
 
Not really enough info to say for sure but if you are building storage for a solar system you want deep cycle batteries. Since you are listing cca (cold cranking amps) it sounds like you are looking at engine starting batteries. Not at all what you want for energy storage.
 
OK I am looking to get batteries. found some 1100 cc 950cca 6v industrial tractor batteries for $50 each or 1050cc 750 cca 12v marine for $75
What is better the 6v or 12v and can you mix batteries like four 6v and two 12v running a 24 volt system
Starter batteries are very poor storage batteries. Neither of those is suitable.

You want deep cycle batteries, no starter batteries. Starter batteries are not likely to last more than 6 months used as deep cycle, and won't give nearly as many amp hours per cycle until they die.
 
What about boat or golf cart batteries or electric car ni-cad. what's better.
 
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OK thanks. I thought all boat batteries were deep cycle> so golf cart are better.
 
OK I am looking to get batteries. found some 1100 cc 950cca 6v industrial tractor batteries for $50 each or 1050cc 750 cca 12v marine for $75
What is better the 6v or 12v and can you mix batteries like four 6v and two 12v running a 24 volt system
All batteries in a series string need to be matched as in same type, size, brand, capacity and voltage.
GC2 are most common in 6v so you need 4x. Costco has them at a good value(most stores). I think Sam's Club has some GC8 so you just need 3x.

If you will be cycling these daily consider a 24v lithium battery.
 
All batteries in a series string need to be matched as in same type, size, brand, capacity and voltage.
GC2 are most common in 6v so you need 4x. Costco has them at a good value(most stores). I think Sam's Club has some GC8 so you just need 3x.

If you will be cycling these daily consider a 24v lithium

All batteries in a series string need to be matched as in same type, size, brand, capacity and voltage.
GC2 are most common in 6v so you need 4x. Costco has them at a good value(most stores). I think Sam's Club has some GC8 so you just need 3x.

If you will be cycling these daily consider a 24v lithium battery.
So if i match 2x12V in a series string, i could connect to another series string of 2x12v in parallel even if they are different types, ah rating, new vs old, brand...

My current bank consists of 2x12v 82.5ah + 2x12v 82.5ah for a total of 24V 165Ah. If i read correctly, i could add 2x12v 105Ah in parallel to the existing bank for a total of 270Ah... Am i getting this right?
 
So if i match 2x12V in a series string, i could connect to another series string of 2x12v in parallel even if they are different types, ah rating, new vs old, brand...

My current bank consists of 2x12v 82.5ah + 2x12v 82.5ah for a total of 24V 165Ah. If i read correctly, i could add 2x12v 105Ah in parallel to the existing bank for a total of 270Ah... Am i getting this right?
Yes that combination is fine while in use or on float charge. If you store them without a float I would separate the parallel strings.
 
The fewer the parallel strings the better. Most LA battery manufacture I have read on say max is three. Ideally one. One string can do most of the work and you want know.
 
The fewer the parallel strings the better. Most LA battery manufacture I have read on say max is three. Ideally one. One string can do most of the work and you want know.
Would the setup i just described be considered 3 strings?
 
Yes that would be 3 strings. All cables need to be the same length. Main positive from one corner and main negative from the other. Check all connections for corrosion in battery box monthly.
 
Yes that would be 3 strings. All cables need to be the same length. Main positive from one corner and main negative from the other. Check all connections for corrosion in battery box monthly.
Awesome thanks!!
 
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