Battery Charging

jekyl

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I've just replaced my two house batteries with lead acid wet cells of 85amphr each. I have a Cetek charger and as the batteries are in series do i only need to hook up to one for them both to be fully charged?
 

wspitler

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If they are 12V batteries, they can't be in series unless you have a 24V system, not likely. The negative (ground) terminals are normally connected as are the positive (hot) terminals to be in parallel. One charger will charge both if connected to either one, if they are in parallel. Series batteries are connected with one positive to the other negative creating a 24V battery for things like trolling motors.
 

ttles714

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The right way to connect your charger to the batteries in parallel would be to connect the charger positive to batt "A " positive,... and the charger negative to batt "B" negative ..... makes no difference which is "A" or "B"
 

seasick

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wspitler said:
If they are 12V batteries, they can't be in series unless you have a 24V system, not likely. The negative (ground) terminals are normally connected as are the positive (hot) terminals to be in parallel. One charger will charge both if connected to either one, if they are in parallel. Series batteries are connected with one positive to the other negative creating a 24V battery for things like trolling motors.
If the batteries are in parallel, are on a battery selector switch AND the selector is off, battery 1 or battery 2, you will only charge the battery that you connect to unless you have a dual port charger.
If you select position BOTH you will charge both ( assuming no isolater).
I do not like to charge both unless I am certain that the batteries are the same models and the same age and condition and even then I am hesitant.
 

jekyl

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Very interesting Seasick, as I usually charge with position OFF and have found I need to charge each battery individually to achieve Full Charge to both. So that makes sense then.

I will also try Positive to Batt 1 and Negative to Batt 2 as "ttles" suggests as both batteries are same make and similar vintage.

Thanks for all the ideas and thoughts guys. As I suspected there is a little more to it than just clipping on the pos to pos and neg to neg. :doh
 

seasick

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jekyl said:
I will also try Positive to Batt 1 and Negative to Batt 2 as "ttles" suggests as both batteries are same make and similar vintage.

if the batteries are wired correctly and the battery switch is on OFF, Batt 1 or Batt 2, then connecting as you reference above will only charge battery 1.
There is no advantage to connecting one lead to one battery and the second to the other battery. In reality, it could be less effective should there be a poor connection between the battery grounds. The best place to connect the charger leads is directly to the battery posts on the same battery.