solar or big amperage battery charger?

megadesertdiesel

megadesertdiesel

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I got to talking with a buddy about upgrading my solar to support 600AH of lithium. While talking we were discussing a larger converter/charger to support those cloudy days. Found a Recpro 125A charger/converter on Amazon for $189. This had me thinking i could run the large charger or even a second 125a charger plus the OEM 75amp charger and let the individual battery BMS handle the equalization. Adding solar panels on the roof with extra holes in the roof is not ideal. Plus an expensive MPPT charger will only net me maybe 30-50 amps of charging.

Running the 5500 generator for a couple hours jamming in 75amps from original charger and another 125amps should do the trick. We only use a 1500 watt inverter for the residential refrigerator and two monitors for the wife's work station, never use the tv's as we have ipads.

Am i crazy?
 
Having dealt with both, the generator running a charger is way easier.

If you're constantly running low on fuel (like we find ourselves), the panels are nice. If they're permanently mounted, the flat angle means you'll need more than you would if they were tilted. Tilted means more work/shit to deal with packing/unpacking.

I currently have 200w of panels and 200Ah of batteries (in a Yeti 3000X). It won't hang on a weekend if I try to run the Dometic fridge on 110v, but we're also running a CPAP all night, plus my kids are constantly charging shit.
 
What about a Honda 2200W Gen for the night to keep everything charging while you sleep? Very efficient on fuel, quiet and portable for other needs.
I have 400W of Solar with (4) Interstate Marine/RV Deep Cycle 12V Batteries @ 90AH each going on 2 years now with a 1500W Inverter for the Residential Fridge and seem to have no issues with battery power. No CPAP so I know that helps, but I do run the TV's every now and then and even on cold nights the heater kicking on throughout the night I have yet to get so low that I couldn't start the 5500 in the AM....But I do run a Honda Companion 2200W sometimes at night before bed just to top off everything.
If you decide to get a small Inverter Genny just make sure to get one with a 30Amp Connector and why I chose the Honda Companion, on the bigger / newer Trailers you need a 30amp hookup....it makes a difference!
 
Meter Tech said:
What about a Honda 2200W Gen for the night to keep everything charging while you sleep? Very efficient on fuel, quiet and portable for other needs.
I have 400W of Solar with (4) Interstate Marine/RV Deep Cycle 12V Batteries @ 90AH each going on 2 years now with a 1500W Inverter for the Residential Fridge and seem to have no issues with battery power. No CPAP so I know that helps, but I do run the TV's every now and then and even on cold nights the heater kicking on throughout the night I have yet to get so low that I couldn't start the 5500 in the AM....But I do run a Honda Companion 2200W sometimes at night before bed just to top off everything.
If you decide to get a small Inverter Genny just make sure to get one with a 30Amp Connector and why I chose the Honda Companion, on the bigger / newer Trailers you need a 30amp hookup....it makes a difference!
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I don't want to be "that guy" running a generator all night, that's just annoying to listen to while sitting by a campfire.
 
Rockwood said:
Having dealt with both, the generator running a charger is way easier.

If you're constantly running low on fuel (like we find ourselves), the panels are nice. If they're permanently mounted, the flat angle means you'll need more than you would if they were tilted. Tilted means more work/shit to deal with packing/unpacking.

I currently have 200w of panels and 200Ah of batteries (in a Yeti 3000X). It won't hang on a weekend if I try to run the Dometic fridge on 110v, but we're also running a CPAP all night, plus my kids are constantly charging shit.
Click to expand...
Fuel cans and tank on trailer and 40 gallon fuel station in Toyhauler mostly for generator. No gas issue over a 10 day dune trip last week.

I have 380 watts of solar and 300AH of lithium with 300AH more very soon.
 
Here is my plan, should have everything installed this weekend.

IMG_8140.jpeg
 
megadesertdiesel said:
Here is my plan, should have everything installed this weekend.

View attachment 134724
Click to expand...

Seems overly complicated to me. If you are only powering a residential fridge and a few monitors why do you need such a high charge rate? Where is the draw coming from on the batteries that you need to replace so much power? Why not just upgrade your inverter to an inverter/charger and not have all the wiring, shunts and switches of the additional chargers? My moho has a 3000 watt inverter with a built in 125 amp charger.
 
Dockmaster said:
Seems overly complicated to me. If you are only powering a residential fridge and a few monitors why do you need such a high charge rate? Where is the draw coming from on the batteries that you need to replace so much power? Why not just upgrade your inverter to an inverter/charger and not have all the wiring, shunts and switches of the additional chargers? My moho has a 3000 watt inverter with a built in 125 amp charger.
Click to expand...

Good question, i guess its fear of not having the power. I'm used to AGM batteries and going to bed with 60-70% of battery power, waking up to power levels in the 50% range. We were having to run the generator for a couple hours until the solar started to put out.

With the our new 600AH of Lithium, maybe i will not need all that charging power. Time will tell.

One good thing that will come out of this will be cleaning up the horrible rats nest of Genesis Supreme Vortex wiring at the batteries. With extra points given to no more off gassing and battery corrosion.IMG_8132.jpegIMG_8130.jpeg
 
You want to clean up the rats nest which makes perfect sense. But you are creating another one by having an inverter plus 3 other converter/chargers. Get rid of the 3 converter/chargers and just have one inverter/charger. You need a bigger inverter anyway. You will have lots of battery power available. Don't you want to be able to make coffee in the morning without running a gen?

And you don't have to replace your batteries with the same group size. Looks like you have space. Rather than doing 6 batteries, why not just do 2(ea) 300ah batteries.

And I would rethink the solar upgrade. The nice thing about solar is it is simple and once set up, you don't have to think about it or do anything with it. It just works. Where do you use your RV most? I would add solar and jus augment that with charging for when it's cloudy.

Have you already bought LiPo batteries? Make sure you can parallel 6 of them if you stick with that plan. Many of them are limited to paralleling 4 batteries in a string.
 
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We went with Victron MultiPlus 3000s and inverterted the entire trailer with the exception of 2 of the 3 A/Cs. The MultiPlus can charge at 120a (I have it set to 100a) which made a huge difference. We have a 460ah lithium and our idle draw is 6-10a depending on whether or not the fridge is actively cooling. That battery will power everything for about 20 hours (TV, soundbar, misc light, occasional microwave use, vacuum, etc.).

Being able to charge the battery from dead to 100% is less than 5 hours on the generator is pretty nice. I'd vote for the inverter/charger.
 
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