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Batteries & Charging

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Old Jan 8, 2014 | 08:55 PM
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Batteries & Charging

Have a question for you experts. With our trucks having two batteries, how can you charge them both at the same time while in the truck, or can you? I have been told that if you connect to one battery it ill charge both, but I know that is not true. Do any of you guys use a battery maintainer? If so what brands?

Thanks,

Chris
 
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Old Jan 8, 2014 | 10:09 PM
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I'm no expert but............
It is true, both batteries are connected to the same charging system, so connecting the charger to either battery or a ground and a positive contact like the alternator or starter + cables will charge both batteries.

I have never used a battery maintainer, I'm sure they work fine. A lot of guys over on Corvette Forum use them since a lot of them don't drive their vettes in the winter.

If I need to charge a battery I like to disconnect it from the vehicle just as a safety precaution to protect the electrical (ecu, pcm etc.) from a possible AC current surge.
 
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Old Jan 8, 2014 | 10:16 PM
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Originally Posted by TCMATHEWS
I have been told that if you connect to one battery it ill charge both, but I know that is not true.
How do you know that this is not true?


I use a CTEK 3300 maintainer:
Amazon.com: CTEK Multi US 3300 12-Volt Smart Battery Charger: Automotive Amazon.com: CTEK Multi US 3300 12-Volt Smart Battery Charger: Automotive
 
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Old Jan 8, 2014 | 10:25 PM
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It will charge both

just takes longer there hooked together with Battery Cables


The ONLY Way it WONT Charge them is if the Batteries are in to Deep of a discharge state The Battery charger may Not be Able to pull current thru Both

But that's^^Mostly on Golf Carts where you have 6+ Batteries hooked in series

Ours are in Parallel so it really should be No Problem doing Both with even the Cheapest of Battery chargers
 
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Old Jan 8, 2014 | 10:28 PM
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I don't drive my truck much in the winter because it is basically the race trailer puller but I use a maintainer on it. I usually don't put it on all the time but I will let it charge all day usually once a week. I will put the charger on the passenger battery first, as I have been told it is the primary battery and let it charge completely and then just for good measure I will stick it on the passenger battery. I believe that both batteries charge from the one because it take a lot less time to get the charger to read full charge on the driver side battery. I use a Die Hard Trickle 2 amp trickle charger usually, but if I want to charge it quickly I will but the 40 amp charger to it. I bought the 2 amp charger at Sears for about 20 bucks and the larger charger was about 50 or 60 bucks.
 
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Old Jan 8, 2014 | 10:30 PM
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My vote is for a Battery Tender Jr. It always keeps my battery in a ready state, not overcharged and not weak. Best if you take short trips, which fail to fully charge your battery fully, or infrequent trips. They provide a semi-permanent plug-in harness, which makes connecting it up a "snap".
 
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Old Jan 8, 2014 | 10:40 PM
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I think the Good Battery tenders also desulfate battery too


But the Best thing you can do is Use a High Output alt
 
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Old Jan 8, 2014 | 10:45 PM
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Originally Posted by Green96
I don't drive my truck much in the winter because it is basically the race trailer puller but I use a maintainer on it. I usually don't put it on all the time but I will let it charge all day usually once a week. I will put the charger on the passenger battery first, as I have been told it is the primary battery and let it charge completely and then just for good measure I will stick it on the passenger battery. I believe that both batteries charge from the one because it take a lot less time to get the charger to read full charge on the driver side battery. I use a Die Hard Trickle 2 amp trickle charger usually, but if I want to charge it quickly I will but the 40 amp charger to it. I bought the 2 amp charger at Sears for about 20 bucks and the larger charger was about 50 or 60 bucks.


Yes they Charge together since they are connected with Battery cables

The Further Battery don't get as Fulley charged because wire resistence basically something like Voltage Drop due to resistence

To get a More even charge one may need to Hook the Charger hot lead to one Battery and the Charger Negative Lead to the Other Battery IDK if this theory really changes anything But maight make the Charger Work the entire system instead of concentraited at 1 battery basically so when it senses enough flow thru first battery it Shuts off regaurdless of second battery state of charge

I also think we would Benefit from Battery rotation cause Normaly the Passengerside HOT+ really gets Cooked
 
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Old Jan 8, 2014 | 11:12 PM
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Originally Posted by BLADE35
I think the Good Battery tenders also desulfate battery too


But the Best thing you can do is Use a High Output alt
The 190 amp DC Power alternator is on my list.
 
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Old Jan 8, 2014 | 11:14 PM
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Originally Posted by BLADE35
Yes they Charge together since they are connected with Battery cables

The Further Battery don't get as Fulley charged because wire resistence basically something like Voltage Drop due to resistence

To get a More even charge one may need to Hook the Charger hot lead to one Battery and the Charger Negative Lead to the Other Battery IDK if this theory really changes anything But maight make the Charger Work the entire system instead of concentraited at 1 battery basically so when it senses enough flow thru first battery it Shuts off regaurdless of second battery state of charge

I also think we would Benefit from Battery rotation cause Normaly the Passengerside HOT+ really gets Cooked
I have charged that way as well. I just do what I can because buying two batteries at once is quite a chunk of change.
 
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Old Jan 8, 2014 | 11:29 PM
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I hear ya

With running my DC Power 190amp I tried to top batteries off once and the charger would shut off after a minute

But according to the Instructions in my charger it says to unhook the Batteries from each other and charge 1 batt at a time what is Probably Best and More Correct way to do it and also puts Less Load on the Charger
 
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