24V Charging Question

[bear0214]

I have 2 - 12V FLA deep-cycle batteries for my boat trolling motor connected in series to make 24V.
For charging, can I connect one 12v 6A charger to the 24v series pair and charge both at the same time?

Can I connect 2 -12v 6A chargers to each battery without disconnecting the 24v series connection?

Or, should I disconnect the 24V series connection and charge both 12v separately?

Going on a camping trip with the boat and want the easiest and quickest way to recharge my trolling motor batteries.

Thanks for the help, John in Montana

 

[FilterGuy]

For charging, can I connect one 12v 6A charger to the 24v series pair and charge both at the same time?

If you mean like this: NO


If you mean in parallel like this. Yes. This works


(Some folks will tell you to put the positive charger lead on one battery and the negative on the other. As long as you charge them all the way up it does not matter which way you do it)

Can I connect 2 -12v 6A chargers to each battery without disconnecting the 24v series connection?

Yes This works.

Or, should I disconnect the 24V series connection and charge both 12v separately?

Yes this works

 

[bear0214]

Thanks for your help FG! Much appreciated.

 

[SamDeleted]

(Some folks will tell you to put the positive charger lead on one battery and the negative on the other. As long as you charge them all the way up it does not matter which way you do it)

Yea doesn't matter once in a while, charging/discharging unbalanced over the life of the batteries might cause uneven degredation

 

[Substrate]

As a preventative maintenance measure, every once in awhile - especially if brand new - charge each separately. If you have a multimeter, and can measure more than 0.1V difference between the batts, recharge them separately again as they can get out of balance with each other.

 

[FilterGuy]

Yea doesn't matter once in a while, charging/discharging unbalanced over the life of the batteries might cause uneven degredation

In this particular case it is only charging. Even if one battery charges a little faster, if the set is charged to full, the other battery will catch up once the first battery reaches accumulation. They will never stop taking current so the difference will always be there but it should not be too bad.

Either way, I think the OP is going to use two chargers 'in situ' so it does not matter.

 

[bear0214]

Either way, I think the OP is going to use two chargers 'in situ' so it does not matter.

Correct, I am going to watch these closely, the batteries are brand new Interstate Group 27's. The trolling motor is new also, a Minn Kota Power-drive 70 which includes a button to test total capacity by percentage, I think best practice is to run the batteries down to 50% before recharging? Yes?