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2 different batteries for 24v. trolling motor

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2 different batteries for 24v. trolling motor

Old 01-14-2003, 11:28 AM
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Default 2 different batteries for 24v. trolling motor

Buying a 24v. Riptide trolling motor and have one Group 27 and one that's smaller & ~ 150 AH less. Any problems hooking up two deep cycles of different size and, therefore, different Amp Hours? Will I hurt the larger one?
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Old 01-14-2003, 11:50 AM
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Default 2 different batteries for 24v. trolling motor

It will discharge nicely, you're problem is going to kick in when you try to recharge them.

Thom

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Old 01-14-2003, 02:05 PM
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Default 2 different batteries for 24v. trolling motor

I will connect them to a 20 amp 2-bank Dual Pro charger so I figured that would charge them according to their individual needs. Have I overlooked something Thom?
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Old 01-14-2003, 02:23 PM
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Default 2 different batteries for 24v. trolling motor

You'd still have to disconnect the bridge you used to connect them in series before you charged them. If you did that I would work, but I think that the discharge is going to be a bit lopsided towards the larger battery, but I'm not sure about that - just sort of an intuitive guess. But if you do isolate the batterys and you have a charger than senses each output line separately then you should be OK, I'd think. I don't know a whole lot about batterys to tell the truth. I'd give someone like Sue D at Guest a call and ask here if I were you.

Thom

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Old 01-14-2003, 06:47 PM
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Default 2 different batteries for 24v. trolling motor

Thom,I have to admit I enjoy reading your posts and you are pretty well read,but my buddys bass boat has a 24 volt riptide trolling motor and has no problems with the dual pro charger there actully separate chargers in one unit.You can run the trolling motor and actully start the boats engine at the same time with one of the trolling batterys at twelve volts.The crossover can stay in place when chargeing.JMO

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Old 01-15-2003, 05:25 AM
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Default 2 different batteries for 24v. trolling motor

Tim,

I am sure there are some chargers that sense the separate batterys state of charge and compensate for it, I just don't have any idea which ones do and which ones don't. My guess, and once again, I don't know much about this at all, is that if you have batterys of two different capacitys bridged it will force the charger to sense the average state of charge between the two, based on resistance to the acceptance of charge, or voltage output. So if you have a small one connected to a large one and start stuffing amps in the small one fills up but the large one doesn't and the average state of charge is something less than 100% for the combined pair even though the small one is fully charged. So the charger keeps on cranking in amps and boils the small battery (further reducing the indicated state of charge) while trying to achieve a now impossible full charge state. Like I said, I don't know that to be the case, but it seems intuitive to me that it would work that way.

Enough of my blabbering, its all just a guess on my part anyway. If you say it will work that is all the word I need.

Thom

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Old 01-15-2003, 06:46 AM
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Default 2 different batteries for 24v. trolling motor

Heres the concept,your thinking in terms of 24 volts,Im thinking at 12 volts and chargeing each battery separately.If you connect a positive charge wire to the positive of one battery and the negative charge wire to the negative of the other battery you would need a 24 volt single charger.This is not the chase although you could if they were both the same rated and sized batterys.Think of two separate chargers and two separate batterys and ignor the jumper crossover wire which makes it 24 volts because unless your going through both batterys you still only have 12 volts at each battery.Does this make sence to you.You can call the trolling motor Doctor in Long Beach California I dont have his number off hand but he could explain better than I can if you or someone else here is interested.JMO

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Old 01-15-2003, 11:12 AM
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Default 2 different batteries for 24v. trolling motor

Thom, I may be wrong, but I believe you are thinking about batteries in parallel where as in a 24 volt trolling motor set up the batteries are hooked up in series.

There is no way in this setup for one battery to pull from the other except when power is being pulled and I'm am not even sure about that occurance. When being charged, in every setup I know of using consumer onboard battery chargers the batteries are charged independently.

As far as the setup in the original question, should work fine until the smaller battery runs low.
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Old 01-15-2003, 01:39 PM
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Default 2 different batteries for 24v. trolling motor

What a concept, eh? It does give the impression that I should be OK using two different batteries since each bank is like a separate charger, sensing the individual needs of the battery to which it's connected.

Thanks for all the inputs.
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Old 01-15-2003, 06:26 PM
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Default 2 different batteries for 24v. trolling motor

You will be fine,in series they become one big battery at a higher voltage,but chargeing them separate at 12 volts.Call the trolling Motor Doctor,he is a warranty station for most brands of trolling motors and he sells dual-pro chargers,he will reassure you,his # is 562/4340943

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