Anyone understand electricity??? Please help me :-/ NOCO Batteries?? ARB Fridge??

I tried to convince them to make a cordless fridge, but they weren't in love with the idea. The margin was super low. I think we are going a different direction and making a battery backup/portable UPS that uses a common/popular power tool battery platform.

 

Be a VERY good idea. I’d be shocked if someone won’t have one in the next 6 months the way things are progressing. Think of all the people who would like a fridge but not the permanent wiring in there DD vehicle. Good luck man. Sounds very smart to me

I wouldn’t think the market needs a new fridge, just a mountable power supply for the models already out there.

 

I think it's probably a lot less ppl than you might think. This overlanding thing, while popular to us, is still very niche. Not many people are spending $600 on a fridge for their truck.

 

Why not just swap in an AGM battery? One 27F AGM battery should do what you need. Go group 31 if you need more juice.

 

@YOTA 4X4 Hey sir, I might have good news. I have devised a portable battery system and I have been putting off making a video of it cause I was working on some other projects, but I will take the time today to film and perhaps edit together a simple video that will explain how to do this.

I use a 95AH AGM battery, 8 gauge wire, a 30 amp breaker (it's sized properly to the specs of the charger), a CTEK DC-DC Charger, anderson connects for quick connects, and a US Marine USB/DC plug/Voltmeter with a NOCO battery box. What this makes is a 100% modular, portable power cell for my fridge, air compressor, small winch, power inverter, phone charger, and lights. I built a YETI GoalZero 1400 for about $500 basically, with a few improvements.

1. The DC DC Charger recharges the Aux battery at ~14.6 volts instead of 13.3, because i'm not relying on the Alternator voltage (in the case of a VSR or just a disconnect switch).
2. It's prewired for both the 4Runner and Tacoma with the anderson connects, so once I set the battery in the vehicle, it's hooked up to the vehicle in 30 seconds.
3. The 30 Amp breaker gives me a hard disconnect for working on the system or safety reasons.
4. The DC DC Charger already accepts inputs for Solar panels, and requires no programming, it just works.

RUNTIME:
That setup ran my portable fridge for 4 days in the desert of Big Bend. However....driving around 2 - 3 hours completely recharges the battery, so as long as I drive that long my timer resets. I assume adding solar might add another day of runtime to the setup.

 

Does 95Ah mean you are only discharging the battery 47.5Ah?

 

Yep, don't take the AGM batteries down too low it drastically shortens their life span. Lipos are great.

 

Short answer, I normally don’t have much of a reason to discharge that low, because it’s rare that I go 4 days or so without cranking up the truck and charging.

Also, I use a deep cycle battery, and I paired it with a very intelligent DC-DC charger that does a desulfation in addition to being a 5 step charger.

I’ll put it this way. I can run the Fridge, charge phones, run LED lights for 2 or so days without going below 12v. Once you get below 12v, the battery voltage drops fairly quickly. I don’t like to run the battery into 10 volts at all, but it’s rarely an issue because I’ve cranked my truck up by then and I’m back to a full charge with little effort.

I don’t worry too terribly much about how much % it runs at, because the CTEK charger manages it and can even repair it if needed. I also have a NOCO Genius wall charger that I use when I’m not in the vehicle to keep it up.

 

https://youtu.be/LDZ84tkcnaE

 

I’m curious just for determining the useable watt hours it has

 

It even has solar input! i had no idea of this ctek product. What a game changer.

 

Research it, it's the new hottness. I discovered it while watching Australian off roading videos. There aren't many sold in the states, they were kind of hard to find info about.

It has a low voltage cutoff to protect the primary battery from dropping low and not cranking like a VSR.
It has a 5 step charger like a fancy wall charger.
And the solar input will allow it to open the switch once the secondary battery is full and start charging the primary battery.

 

At 100AH, which is rated at 20 hours typically, the conversion would be Amps x Voltage = Watt. So

100AH x 12v = 1200WattHours

And assuming the same 20 hours of runtime:

1200WH / 20hrs = 60watts / hour

Then factor inverter losses if running an inverter @ 20% ish.

60 x .80 = ~48 watts / hour for 20 hours.

Caveats:
Typically you are pulling more than 48 watts (cooking items), or less than (lights). More amp draw will lessen runtime, less will extend. It's not exactly proportional.
You mention you're worried about going over 50% drain on the battery. I typically monitor voltage to determine that more than estimate watt hours. So adding a voltmeter to your battery is a must.

 

I understand the math. I'm still not clear on if a 100Ah deep cycle battery gives you 100Ah.

 

This is nice. I've been researching portable DIY solar generator with a 500w inverter, mostly for camping or emergency needs. Using the CTEK as my charge controller I can charge it multiple ways! Sweet. I guess i just need to wire some 8g to the cubby hole in the bed.

 

I'm embarrassed to admit I've had my CTEK Dual for about a year now and I still haven't installed it. @fajitas21 your setup looks nearly identical to what I was planning with standalone batt box, Anderson plugs and all. Your video might just be the inspiration I need to finally get this job done. Curious what deep cycle battery (brand/model) you used. That's about the last decision I need to make.

 

Interstate battery group 27. I think. A friend got it for me for $50.

 

Looks good, I have a question though, where is the fridge to be installed? I am thinking about a port at the tailgate and plotting my wire size for a small fuse panel aft, probably run 4awg to the panel(Blue Sea 60 amp) and then size the feed for the fridge accordingly. (Domestic CFX 65)
Planning to add a panel and house battery once I get a different shell.

Thanks to the math gurus for their input and apologies for the thread jack