Onboard Charger Options? Is it really this simple or am I missing something?

Ok, So while I consider myself an above average mechanic, sadly I consider myself a below average electrician and I want to do a sanity check with the experts on here.

I'll keep this a simple question. Instead of dual batteries I plan on running 1 group 31M in a Pelfreybilt battery cage. My question is with my fridge being hooked directly to the battery can I use an onboard charger to basically keep my battery full when shore power is available and the fridge is running?

Right now I pack up everything a day or two before, keep my fridge in my dining room running off 120V than the morning I leave I haul it full out to the truck. Last time I went I left the fridge in the truck but ran an extension cord to it from my car port to get it cold and maintain until it was time to leave. I realize that I can run a day or two without being plugged in but if power is available can I simply use an "on-board charger" like a NOCO or MinnKota single bank 10A to keep the battery full while the fridge and other things use power at the same time. In my feeble mind this seems simple but I could be missing something.

Also say I'm out in a long term camping spot and plug in a portable solar panel to my battery, could I also run my Honda Generator to the On Board Charger to keep everything full if I was remote and say not running the truck for a week?

Please give me a sanity check, because it seems to me that this would all work out fine providing the chargers are "smart"

Thank you all.

Oh might as well ask the question as to what onboard charger to use while I'm at it. It'd likely be mounted under the hood so it has to be waterproof, please vote or comment with a better option thank you.

 

Yes, you can do that. The solar charger should have a diode in it such that the power flows only from the panel to the battery, and not from the battery (ie your shore power) to the panel potenatially wrecking the solar panels.
The fridge load as you've noticed is not a continuous load, the compressor starts up when its needed and shuts off when its not to maintain the fridge temperature within a certain range.
Your plugged in shore charger keeping the battery up is running continuously, until the battery is charged up, so it does not have to match the amperage draw of the fridge.

I used this Noco charger and mounted it behind the windshield washer fluid tank and above the area where the ABS unit is on the TRD Sport.

 

That's the exact charger I was thinking, Just hook an outlet to the outside of the truck somewhere to make it even easier and I'd be GTG right? Thanks for the sanity check, I look at some "overlanding" electrical systems and I'm dumbfounded. I am just going to use 1 battery and an onboard charger... seems way to simple but we will see. Thanks!

 

Sub... I have the Noco and Odyssey 31m but havent hooked any of it up yet, think my batt is toast from letting it completely discharge. It sat for a couple months with some parasitic voltage, the Noco would not revive it

 

Yes, that will work. My plan is to use a solenoid linking the accessories fuse panel to the battery, with a voltage sense module. If the battery voltage dips below a certain threshold then the current keeping the solenoid on will be dropped, and the accessories turn off, but you will still have starting the truck ability. To turn the solenoid back on requires re-starting the truck or simply a momentary switch to turn it back on if the battery voltage is high enough. I believe they call this a Low Voltage Disconnect or LVD.

Examples:
Timer + LVD
https://powerwerx.com/automotive-dc-timer-lvd-battery-guard
just an LVD
https://powerwerx.com/low-voltage-disconnect-battery-guard

 

Sooooooooo...... I'm not an electrical expert BUT. I successfully revived a completely drained AGM battery this spring (it was installed on my FJ40 and drained totally over the winter) I used the process detailed on the Optima website with 100% success. I elected for option #2. I did it a few times before it really took, but I carefully checked the battery for heat build up. (disclaimer I did it outside just in case)

https://www.optimabatteries.com/en-us/support/charging/resuscitate-deeply-discharged-battery

Basically hook up a good fully charged battery with jumper cables to the dead AGM. Than hook the charger to the Good battery so it can sense voltage. Charges one into the other. Worked perfect

 

Ahhh that is a very cool idea!!!!!!!!! My fridge is an ARB which has 3 different low voltage cut off settings. If I decide to add any other substantial draws I will definitely be doing that. That's super smart!!!!

 

AM bump

 

Early afternoon bump.... everyone is talking about Deisel fuel in a gas tank? No one is interested in Shore Powered Tacos? Bummer