Best Battery Maintainers for RVs: Brand Picks, Sizing, and Dual Bank Tips

[Isaac-1]

Its not just temperature it is the voltage ratings of the MOSFETs and SCR's on the circuit boards

 

[DonTom]

Anything over that and I would stick with a known brand that prominently advertises the VOC limits such as Victron where most models can handle a VOC of 100V or more.

Which is what I did for my Y2k RV. I installed a Victron Solar Controller with a 100 Voc rating.

This 2022 Class A I am now in only has the stock 100w worth of solar on the roof which was around 24Voc, but it still came with a Go-Power Solar controller with a rating of 100 Voc. That was handy because I cut into the solar wires at the controller (located in an outside compartment) with a jumper and I can add a couple of solar panels in series.

I once tried three more in series (four total) until an extra sunny day in KOFA shut off the controller when the input voltage got too high.

I didn't bring my solar panels for this trip as I didn't expect to boondock anywhere, and here I am at Gunsight Wash. I only have the 100W on the roof here.

NBD, the 5.5 KW Onan works well enough in this.

I normally use my Y2K RV for boondocking, except for places such as OPCNM where it is very level. And I will be there after here for a few nights or so.

The Go Power solar controller has two separate DC outputs, one for the engine battery.

-Don- Why, AZ

 

[Rene T]

While we’re in the subject of battery maintainers, I have a DuraMax deisel. It has two batteries hooked in parallel. When hooking up a maintainer do I just connect it to one of the batteries?
I have a grandson who wants to put a maintainer on each battery. Which is the proper way? One maintainer or two?
This is my truck on a frozen lake in NH today He spent last night in his trailer/bob house seen in the background . The outside temps was -4. He has a Mr Buddy heater and he said he was warm enough. Crazy!!!

 

[Mark_K5LXP]

If the batteries are hard wired in parallel then a second maintainer isn't going to add anything. Self discharge and nominal parasitic draws are readily overcome with a single maintainer. A voltmeter will confirm if a maintainer is keeping up both batteries.

Mark B.
Albuquerque, NM

 

[DonTom]

Just use one, if it's a three amp battery maintainer then each battery will charge up at 1.5 amps, etc.

But you do not care. It takes longer to charge up to the voltage to turn off, but there is no reason to care when you're only trying to keep the batteries fully charged.

-Don- Gunsight Wash, AZ

 

[Rene T]

Just use one, if it's a three amp battery maintainer then each battery will charge up at 1.5 amps, etc.

But you do not care. It takes longer to charge up to the voltage to turn off, but there is no reason to care when you're only trying to keep the batteries fully charged.

-Don- Gunsight Wash, AZ

Thanks guys. My maintainer is a 2 Amp NOCO

 

[Isaac-1]

2 amps should be big enough for 2 batteries

 

[bigbAZ]

While we’re in the subject of battery maintainers, I have a DuraMax deisel. It has two batteries hooked in parallel. When hooking up a maintainer do I just connect it to one of the batteries?

FWIW, Deltran recommends connecting to the positive of one and the negative of the other.

 

[DonTom]

FWIW, Deltran recommends connecting to the positive of one and the negative of the other.

I see no significant advantage or disadvantage of either way at such low charging currents as charging on two batteries in
parallel.

-Don- Bakersfield, CA

 

[PancakeBill]

FWIW, Deltran recommends connecting to the positive of one and the negative of the other.

View attachment 2414165

I am curious as to this technique. I would always have connected both to the one battery. But same go for the load? For instance, I have 2 in Par, connected to my converter charger to the same battery +/-..is it wrong? Thinking about it I think I see the rational as it would be more balanced?

Just found a video about the technique, The load is more balanced across the battery bank. Now to go change a lead.

 

[DonTom]

The load is more balanced across the battery bank. Now to go change a lead.

At such low currents as charging, it falls under "who cares?" which way it is done. I wouldn't even waste my time thinking about it for a low current battery maintainer. Whichever is easier and safer to get to is the way I would do such.

-Don- Bakersfield, CA

 

[John From Detroit]

I will say again Balanced matters only for BIG loads like a 2000 or larger inverter at full load
And even then I'm not sure how much
If you are holding to say 20 amps on a 200 amphr battery (or battery bank) worry not. +

 

[PancakeBill]

Well I haven’t changed it out yet.