3rd Gen 24/7 fridge power setup help

Hi crew, I posted a while ago about auxiliary power to a fridge in my truck bed. I have since done loads of research and wanted to pose the question again to see where my thoughts are and if I am on the right track.

Back story - I built out the back of my truck for misc use, but it includes a fridge (nothing fancy, 400$ off Amazon) that I want to have permanently on so that I can keep misc food and beverages on hand.

What To Do - Ive heard a lot of bad reports of the dual battery mount that goes in the stock location so have moved on to putting a second battery under the hood on the passenger side. I know it needs to be connected to a solenoid isolator and then to the alternator so it charges when I drive but doesn't drain the house battery. I have heard some bad reports that this tends to drain and destroy the auxiliary battery fairly rapidly (under a year).

My Question: Would it be superior to instead charge the auxiliary battery through solar? Or both? and if so, I would need to buy a charge controller correct? Secondarily, what type of battery may best fit the needs? I know Li would be best but has problems because you need to keep it totally dry and that may be difficult under the hood. Let me know what the deets are, looking to keep it under 1500$ if possible but could spend a bit more.

thanks TW Fam

 

You could save some time an research and just do something like purchase the off grid engineering dual battery system. I recently installed this in my truck. It uses a redarc dc to dc charger that also allows for solar input as well. After installation I wired up most of my accessories to the aux battery which is a group 35 AGM. I have my fridge powered by the aux battery. Whether you do it all yourself or buy this kit, there's no reason you shouldn't be able to charge the 2nd battery while the truck is running using a dc-dc setup and also power via solar when needed.

When I was doing research before I bought it I emailed them and asked a lot of questions and they were very helpful. I also purchased and installed the battery link system so that I can press a button and jump the starter battery from the aux battery if necessary.

 

Yeah ok cool I saw that system and was thinking about installing it. My question to you, does it isolate your aux battery from your house battery when the car is off? Or did you have to purchase another solenoid isolator for that?

 

Yes, the batteries are isolated with this system when the truck is off. As long as you connect your accessories to the auxiliary battery, it will not drain the starter battery. The redarc unit that comes with the setup is a DC-DC charger, so it charges the aux battery when the vehicle is running or from solar, however power is only pulled from whichever battery you connect your accessories to. That is the whole purpose of the system, to have an auxiliary battery to connect your fridge or other items to so that you don't have to worry about draining your main battery. Also, like I mentioned, they are very helpful when answering questions, so if you're still not sure, just reach out to the folks at off grid engineering.

 

This was the setup I made for my fridge. Heavy cables from Starting battery to Blue Sea ML-ACR isolator to twin Optima 27Ms. Added a 110v charger as well.




My fridge lived on top of the battery box. Having the battery in the bed made it much easier than an expensive dual battery mount under the hood. Not suggesting the giant box, just another example.