Adding Batteries Separate From House Battery?

I'm getting the picture that there is a converter in the back with connections to the DC things in the house, all working. The only wrong thing is the battery being far away under he hood. It makes perfect sense to move that battery close to the converter where there is room to add a second one. Leave the existing wire to the engine compartment to allow engine charging.

I have a small class C with a modest #12 stranded wire from the engine to the house, originally the trailer battery charging system, fused for 40 amps but in practise providing no more than 6 amps of charging. The battery isolator is just another little Ford relay in the engine fuse box (position E), labelled "trailer battery charging relay" in the Ford manual.

Ductape wrote:
Check your weight distribution before you put a bunch of lead in the rear.

x2

I'd be be very concerned about how much weight I was adding to the rear. Many motorhomes are heavy in the back anyway. Have you had all 4 corners weighed? If you haven't you should. Batteries are very heavy and you could be causing more problems than you want to deal with.

JYetzer wrote:
Your issues are primarily with efficiency or simplicity rather than safety or component failure?

Yes mostly.
It takes a fairly large and expensive inverter to run a microwave.
I think that money would be MUCH better spent on a generator; no extra batteries needed probably.

Oh boy. Ok.

I only paid $6K for this thing and I'm not sure I want to invest that time or money into a full upgrade. It needs to get us through the next couple years, and most of the time we should have FHU.

At this point I'm thinking we will just get a generator (honda or yamaha 2000watt) and call it a day.

Perhaps I'll build a separate solar charge station for personal devices and the like, but I think I will avoid integration into the RV itself.

Have you looked under the steps leading up into the Class C. I hear alot of folks being able to have a couple of extra batteries mounted here.

You could be able to charge these batteries through your converter/charger setup...

You are aware that your current converter/charger has to be a single mode 13.6VDC Charger basis on the age of your Class C. When you start upgrading the batteries etc you really should look into upgrading your whole battery setup to a more modern multi-voltage converter/charger unit.

Just buying two new batteries and installing them as stand-alone batteries will in a short time make those batteries unusable and harmed beyond bringing them back alive to their original performance.

I can run down my 255AH battery bank to their 50% charge state over night just drawing DC amps for a very few list of things we want to run. This is mainly just pulling around 20AMPS Dc Current for 4 hours or so... I have to bring this battery bank back up to its 90% charge state the next morning if I want to use them again for the next day/night run. I can do this with my 2KW generator connected to my on-board mulit-mode smart mode charger PD-9260C Converter/charger unit in a three hour generator run time. If all I had was the 13.6 single mode charger it would take over 12 hours or of generator run time to bring them back.

If I was to just charge them for a couple of hours here and there they will not get their performance back enough to make the next nights run and would probably only last maybe just a few hour into the night. Once they get down to the the 50% charge lever (around 12.0VDC) then you need to stop using them otherwise you will start doing harm to the batteries.

So the best plan is install a modern battery system first then you can start doing camping off the battery bank and not destroy things...

If your running off the batteries is just running a led light then what you are implying would work great...

Back in the day we did just fine running off of a bag of D-CELL batteries and candles haha...

I got to have my basics HDTV, charging of my computer/tablets batteries, keeping my WX Radio going, a light or two on, and maybe a fan. The rest can be run off of propane...

my two cents worth haha...
Roy Ken

Thanks for the ideas and suggestions everyone.

No free lunch and no miracles - sorry.

The simplist way is to run a 1/0 gauge cable under the chassis, to positive in the rear. Then pin both chassis negatives - both ends to the frame also using 1/0 wire.

I've adopted the Skycraft DLO diesel locomotive cable as my favorite because of it's tough and thick insulation. Light years tougher than battery or welding cable and the Skycraft sourced DLO cable is much less expensive. I use 1/4" poly rope as a route measuring device first then measure the rope before I buy the cable.

This way all the house batteries are ganged evenly and there will be much less confusion. Google SKYCRAFT SURPLUS FLORIDA. Then select WIRE and then DLO WIRE.

You need to read 12volt side of life.

For purposes of this exercise, assume the batteries will be charged via a generator or shore power, and they will be expended during dry camping.

There is no free power, how are you going to recharge the batteries, before you install the solar
You still have to turn off the converter
It will be connected to your AC from the inverter, it will be charging the old battery, even if you disconnected the battery, the converter would still be on, wasting some power
You need a generator and a good modern converter, before you spend money on solar, you can get a deck mount converter, PD, wfco, etc.. And mount it in the rear some place close to the new battery bank
Connect battery bank directly (fused) to the DC fuse panel