12V Batteries Combined in SERIES - Different Size/Capacity OK?

kindafishy

I Post A Lot But I Can't Edit This
Jul 21, 2010
4,299
2,046
hemet/ca/riverside
Name
SCOTT
Boat
bayliner cierra express 2452 "RYLEE'S WAVE RYDER"
They're 12 volt batteries connected in series to get 24 volts.

yes i understand that, im wondering how you charge a 24v bank with a 12v charger?
 
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hucklongfin

Deep release specialist
Jul 3, 2003
9,528
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Mission Viejo
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MarkT
Boat
Blazer Bay 1860
You don't charge a 24v bank you charge 2 12v batteries. I have a 4 bank charger hooked up to all 4 of my batteries. Two are hooked up in parallel via a switch and 2 in series for the trolling motor.
 
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MYNomad

Heading South
Dec 12, 2007
4,201
4,880
Pacific Northwest / West Coast Mexico
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Rick
Boat
Yes
You don't charge a 24v bank you charge 2 12v batteries. I have a 4 bank charger hooked up to all 4 of my batteries. Two are hooked up in parallel via a switch and 2 in series for the trolling motor.
And the grounds of the charger circuits are not common grounds. If they were, it would create a dead short, but they are not. A 24 volt charger could work, but if the batteries are not identical, one will be limiting the other, perhaps severely.
 
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karlow

Twins 2017
Apr 29, 2004
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Duarte/Covina
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karl
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20' skippy Topless /17' whaler Wet Ride (sold) /18' Outrage
Like I said, or Rick said. As for the multi-battery 12V charger, it will work if the chargers have are independent, ie isolated circuits. The first test is to measure for continuity between the ground leads. there should be none. You can solve the problem by unloading that puny GP27 on me at cost. That way you can sleep well. I currently need 2 GP 27 4 my Outrage Project. FYI I typically get them at Costco.
 
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kindafishy

I Post A Lot But I Can't Edit This
Jul 21, 2010
4,299
2,046
hemet/ca/riverside
Name
SCOTT
Boat
bayliner cierra express 2452 "RYLEE'S WAVE RYDER"
Like I said, or Rick said. As for the multi-battery 12V charger, it will work if the chargers have are independent, ie isolated circuits. The first test is to measure for continuity between the ground leads. there should be none. You can solve the problem by unloading that puny GP27 on me at cost. That way you can sleep well. I currently need 2 GP 27 4 my Outrage Project. FYI I typically get them at Costco.

ok thank you. for whatever reason i get it now. so no continuity between charging circuits with in the charger. thanks!
 
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RobertHan

Newbie
Nov 21, 2020
10
1
36
USa
Name
Robert
Boat
Botnia Targa 25.1 GT
It’s a wonderful idea to add a secondary battery to your boat. Doing so will increase the power of your vessel to its optimal performance. Instead of having only one battery, you will now have the power of two and be able to go on longer boating activities. :)
 
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