batteries

dreamchaser

Petty Officer 1st Class
Joined
Aug 31, 2006
Messages
228
What is the advantages of using 2, 6 volt batteries verses 1 12 volt ,,, the 2 6 volt will be deep cycle ,and the 12 volt would not be , it is a 8d type.......thks
 

WillyBWright

Fleet Admiral
Joined
Dec 29, 2003
Messages
8,200
Re: batteries

I see nothing but disadvantages if you're using them to start an outboard. But for a 12v trolling motor I could see it. Assuming they're each the same physical size as most 12v deep cycle batteries batteries, you'd have roughly twice the amp capacity, which should last about twice as long. Of course you could accomplish pretty much the same thing by connecting two 12v deep cycles in parallel. The 6v's would have to be connected in series.
 

tashasdaddy

Honorary Moderator Emeritus
Joined
Nov 11, 2005
Messages
51,019
Re: batteries

you need a 12 volt starting battery for the engine, if you run a lot of accessories, the 6 volt in series, charge lasts a lot longer. most electronics are low load.
 

dreamchaser

Petty Officer 1st Class
Joined
Aug 31, 2006
Messages
228
Re: batteries

Thku guys for the quick reply,,,,so i guess they not sutable for a starting, but good for the other power requirements......and yes they would be hooked up neg to positive then 2 cables running back to the back of the boat . My one goal was to get some weight out of the back of the boat as well, Will 2 rv style, starting deep cycle ie dual purpose batteries be better? or how bout the 1 big 8d? thks
 

dreamchaser

Petty Officer 1st Class
Joined
Aug 31, 2006
Messages
228
Re: batteries

Sorry, forgot to mention right now my single battery is in the back corner ,,,,and this new system will be moved up to the bow.
 

JB

Honorary Moderator Emeritus
Joined
Mar 25, 2001
Messages
45,907
Re: batteries

Moved to Electrics
 

drewpster

Commander
Joined
Oct 17, 2006
Messages
2,059
Re: batteries

I have heard of using 6 volt golf cart batteries in parallel to create a battery bank with greater capacity. I have heard it works quite well. The setup is used mainly for deep cycling, providing power for accessories or trolling. I can't see the advantage in the starting circuit.
 

I/O WALDO

Petty Officer 1st Class
Joined
Nov 16, 2005
Messages
320
Re: batteries

(Series connecting two 6volt golf batts. give 12 volts,--parallel would give 6 volts) two sixes in series give lotsa amp hr capacity.+ they put up with a lot of deep cycling longer than 12v deep c. batts will.
 

drewpster

Commander
Joined
Oct 17, 2006
Messages
2,059
Re: batteries

Thanks waldo, I used the incorrect term before. Connecting batteries in SERIES, doubles voltage.

In series means positive to negative, positive to negative. 6+6=12

In parallel means positive to positive, negative to negative. 6+6=6

Sorry for the mistake.
 

Boatist

Rear Admiral
Joined
Apr 22, 2002
Messages
4,552
Re: batteries

I would not move the battery to the bow of the boat. Vibration is a major killer of batteries and the bow just pounds too much.

Two 6 volts batteries is no better than one 12 volt battery. Either way you have 6 cells. Now if each of the 6 volts is the same size as your 12 volt then they will last longer but if you buy a bigger 12 volt that matches the size of the two 6 volts then they will last the same. Match the amps and capacity and I would prefer the 12 volt.
 

I/O WALDO

Petty Officer 1st Class
Joined
Nov 16, 2005
Messages
320
Re: batteries

An 8D isa cranker,not deep cycle.Two golf 6volts.will kick 2,12 volt, size24 deeps in the butt everytime! We use them on inverter house banks exclusivly. On paper they may look the same butt in the real world there is no comparison.
 

dreamchaser

Petty Officer 1st Class
Joined
Aug 31, 2006
Messages
228
Re: batteries

well, thks guys ...that narrows it down ....Boatist i have no choice but up front .to much weight in the stern .trying to balance my boat some. Waldo ther are 8d marine deep cycle batteries available , mind u $260 ....Im leaning in the agm or spriral construction type ...but pricy as well ....
 

I/O WALDO

Petty Officer 1st Class
Joined
Nov 16, 2005
Messages
320
Re: batteries

Golf batterys are tough as far as vibration goes.All that acid slingin around up ft.could be detrimental.Is the boat in the picture what you r working on?Is YOUR 8d a cranker? AGM is good but won't charge at the same rate as your flooded battery and they don't like to be overcharged.Battery banks should be the same type.
 

dreamchaser

Petty Officer 1st Class
Joined
Aug 31, 2006
Messages
228
Re: batteries

Yes, Waldo that is my boat .I have not purchased the new battery yet........still pricing and shopping round ......
 

I/O WALDO

Petty Officer 1st Class
Joined
Nov 16, 2005
Messages
320
Re: batteries

A 24 size AGM cranker in the back and 2,27 size AGM house up ft and you are set!(and broke!)Connect all the batt.grounds together and put a "on-off" switch in the + cable tween the house and start bank for those engine off periods.Sorry if I wuz too nosey!
 

LubeDude

Admiral
Joined
Oct 8, 2003
Messages
6,945
Re: batteries

You are really going to be sorry if you relocate your batteries to the front. You may suffer bow steer while underway. What makes you think you have too much weight in the back?
 

muskyjim

Seaman Apprentice
Joined
Mar 12, 2007
Messages
43
Re: batteries

I understand Dreamchaser wanting to get some weight out of the back of his boat. I have a 16ft Starcraft and I have had the same concern. With a 70hp motor, 2 batteries and 2- 6 gallon gas tanks in back, that just seems like a lot of weight in back. Not to mention just wanting a little more separation between the gas and the batteries.
 

dreamchaser

Petty Officer 1st Class
Joined
Aug 31, 2006
Messages
228
Re: batteries

Lube Dude ...I have had a porpoising problem with my boat since i changed motors up to the v4 weights ......And now that i have a 1994 120 johnny on which weights 365 + - , A 1992 9.9 2 stroke xlong merc which im guessing is about 80lbs? or more.... I do have smart tabs but when i set them down more they reduce speed .... i think im to stern heavy .......therefore a battery in the front is one way to get some balance. The 120 now launches the boat up and out very well ....so i dont see bow steer being a problem . maybe at trolling speed though ....its either sand bags or a battery to try to hold her down ......any thoughts?
 
Top