Charging dual battery truck

[Lucid Moments]

I have a 2010 Dodge Ram 2500 6.7L that I do not drive regularly. It doesn't sit for weeks at a time, but maybe only once a week on average. I recently replaced both the batteries in it and given the cost I would like for them to last as long as practical. I have read that keeping batteries on a charger/maintainer when not in regular use will extend their life. To that end I am considering buying a NOCO Genius2D to install in the engine bay.

I have a few questions:

1. is this really a worthwhile addition?
2. My understanding is the best way to hook up a dual battery system to a charger/maintainer like this is to put the negative wire the the ground terminal on one battery and the positive to the positive battery on the other battery. Is that correct?
3. I suspect the charging wires that come with the charger aren't going to be long enough to reach both batteries at the same time. Is there any harm in extending the wires, and does the extension need to be equal on both wires?

Thanks in advance for any advice.

 

[BillK]

I have a 2010 Dodge Ram 2500

I recently replaced both the batteries in it

If the original batteries lasted 10 years you got way longer than average life out of them. I wouldnt worry about it. It would be different if you were only using it once a month or longer.
I usually only drive my 99 Tahoe on weekends and the batteries have lasted on average of 6 or 7 years. I think the one that is in it now is at least 5 years old.

 

[Lucid Moments]

I bought it in 2015 and the previous owner told me he had recently changed the batteries which was supported by the date code on the batteries of March 2015 IIRC.

 

[unslow1]

A couple of friends have just gone to the solar chargers on the dash for the diesel trucks that aren't driven daily. It seems to have prolonged the battery life.

 

[wyliesdiesels]

You got 6yrs out of the batteries? Thats pretty good....

 

[Mike K.]

I use a simple battery tender plugged into the cigarette lighter which has worked fine. I use my truck only once or twice a month.

Mike K.

 

[HenryAZ]

Battery Tender makes a two bank maintainer.

 

[mike93lx]

Extending wires is not a problem and they don't need to be the same length.

You just need to make a good connection and should use a wire of the thickness appropriate for the current draw and length. In that application, length doesn't practically matter, so using the same gauge or one gauge thicker will almost certainly be plenty.

Unless you have parasitic draw, I think you are wasting your money for a vehicle that gets driven weekly.

 

[AngryBeaver]

I use a single 12v battery tender on three of my trucks with dual batteries.……

 

[Grogg]

you don't need to hook the negative to one battery and positive to another, unless that's a newfangled thing with those newfangled 4th gen trucks that will fry the computer unless you ask nicely first... but I'm pretty sure the alternator charges just one battery (passenger side) and the driver side battery gets charged over the crossover cable... then the battery temperature sensor is under the drivers battery but not the passenger one, so if you have a bad crossover cable it boils your passenger battery and the drivers one is fine.

my '06, I have an older Noco G7200 I just leave connected to the passenger side battery when I'm not driving it for long periods of time. they always test at the same voltage when I pull them out of the truck

 

[nadogail]

My '99 Chevy 1500 Van with the 305 engine that gets driven almost every Friday afternoon has a Schumacher solar panel on the dash.
I have not had a battery problem in recent years.

Prior to putting the solar panel on the dash and plugging it into the socket on the dash the battery would go flat in just a few days.

 

[American Locomotive]

The batteries in the truck are connected in parallel via. heavy gauge wires. For all intents & purposes, the electrical system sees them as one big battery. Connecting the leads as you described will not do anything different than just connecting both leads to the terminals on the same battery.

 

[FTG-05]

Recommendation for a good solar trickle charger?

Thanks!

 

[Lucid Moments]

So with this question I am not arguing, but am trying to learn. I picked up the idea of hooking the charger across both batteries from some stuff I saw and read about solar and micro-hydro systems hook their charging system up as I described in my original post. Why the difference with my situation? Is it that those systems are generally batteries hooked up in series? Or is it because they run at higher charging rates than the meager 2 amps I am suggesting? Or some combination of the two?

 

[mike93lx]

So with this question I am not arguing, but am trying to learn. I picked up the idea of hooking the charger across both batteries from some stuff I saw and read about solar and micro-hydro systems hook their charging system up as I described in my original post. Why the difference with my situation? Is it that those systems are generally batteries hooked up in series? Or is it because they run at higher charging rates than the meager 2 amps I am suggesting? Or some combination of the two?

It's people overthinking things and not understanding how they work.

You can run 80 amps continuously through a 4 gauge cable. And if you had a big solar setup, you'd have bigger wire connecting the batteries anyway

 

[TractorJeff]

My guess is the confusion over "INTERNET Searching" is not knowing that half the explanations are for series connected 24v systems verses parallel connected 12v systems?

 

[exranger06]

So with this question I am not arguing, but am trying to learn. I picked up the idea of hooking the charger across both batteries from some stuff I saw and read about solar and micro-hydro systems hook their charging system up as I described in my original post. Why the difference with my situation? Is it that those systems are generally batteries hooked up in series? Or is it because they run at higher charging rates than the meager 2 amps I am suggesting? Or some combination of the two?

If those systems have batteries hooked up in series (I don't know if they do or not), then you basically HAVE to hook a charger up that way. If they're hooked up in parallel, then you COULD hook it up that way, but there's really no point. You might as well connect the charger across one of the batteries and it would charge just as well.

When batteries are wired in series, the voltages get added together. For example, if the electrical system in your vehicle is a 24V system (like on some semis), you can take two 12V batteries and wire them in series and you get 24V. Three 12V batteries wired in series gets you 36V, and so on. So if you have a 36V system and a 36V charger, you'd HAVE to connect one charging lead to the positive terminal of the first battery, and connect the other lead to the negative terminal of the last battery, as that's where the difference of 36V is. Each individual battery only has a voltage difference of 12V, and you can't connect a 36V charger across a 12V battery.

When batteries are connected in parallel, the voltage for the whole system is the same as the voltage for each battery. In other words, you can connect as many 12V batteries in parallel as you want, and the total system voltage will always be 12V. You can connect a 12V charger across any one of those batteries, and it will charge all of the batteries simultaneously, because they're all connected together, essentially forming one giant 12V battery.

 

[Lucid Moments]

If those systems have batteries hooked up in series (I don't know if they do or not), then you basically HAVE to hook a charger up that way. If they're hooked up in parallel, then you COULD hook it up that way, but there's really no point. You might as well connect the charger across one of the batteries and it would charge just as well.

When batteries are wired in series, the voltages get added together. For example, if the electrical system in your vehicle is a 24V system (like on some semis), you can take two 12V batteries and wire them in series and you get 24V. Three 12V batteries wired in series gets you 36V, and so on. So if you have a 36V system and a 36V charger, you'd HAVE to connect one charging lead to the positive terminal of the first battery, and connect the other lead to the negative terminal of the last battery, as that's where the difference of 36V is. Each individual battery only has a voltage difference of 12V, and you can't connect a 36V charger across a 12V battery.

When batteries are connected in parallel, the voltage for the whole system is the same as the voltage for each battery. In other words, you can connect as many 12V batteries in parallel as you want, and the total system voltage will always be 12V. You can connect a 12V charger across any one of those batteries, and it will charge all of the batteries simultaneously, because they're all connected together, essentially forming one giant 12V battery.

Thank you, that is what I didn't quite get. If the batteries are set up in 24v (or 36 or whatever) then of course the charger is also at that voltage and you have to hook it up that way. I wasn't thinking about the charger's voltage although that should have been obvious.

 

[dcg9381]

I've got a 2015 Ram 6.7L. I'm getting 3-4 years out of batteries. So you're doing great.
On mine, I verified that my batteries are connected in parallel and that there is continuity when the truck is off.
IE - if you charge one, you're charging the other.