battery backup question

[John in Santa Cruz]

I removed my original dual GC2's...

and the box they were in, along with the vent hose, and installed 2 x 206AH Lithiums like this...

Those are SOK Batteries, I paid $1200 each 2-3 years ago, they are half that now and the new ones have built in bluetooth battery monitoring, and heaters.
https://www.us.sokbattery.com/product-page/sok-12v-206ah-lifepo4-battery-bluetooth-built-in-heater
These have been excellent for me so far, they are very well made batteries, designed to be repairable (metal case opens up, wiring is all neat inside, battery cells can be individually replaced).

by putting them all the way in the back corner, I freed up more storage for my wife, she puts spare blankets and quilts in there mostly. The 'wiring board' wasn't completed when I took that pic... as you can run LFP batts right down to like 10% or even less, you can use almost all of their 5200 watt*hour rating.

 

[Ron in BC]

Why not install a second battery in my trailer? I would still have to watch the charge level on cloudy days, but I would have a lot more amp hours available.

It's worked for me for decades. Nothing like the security of a second, ready-to-go battery independent of the other one.

A few times, in my 19, I did select "both" to give extra amps for the microwave. Otherwise the second battery doesn't require anything except maybe being used and charged from time to time.

Ron

 

[John in Santa Cruz]

I'd as soon have a single 20 gallon gas tanks as two 10 gallon tanks with a crossover switch.

 

[Ron in BC]

I'd as soon have a single 20 gallon gas tanks as two 10 gallon tanks with a crossover switch.

I wouldn't want to fly an airplane or sail a boat across an ocean with all my eggs in one basket. That doesn't really apply to vehicles since running out of gas is careless, not something that happens unexpectedly. It's a different situation when I'm boondocking. Lose a battery with dual batteries, flip a switch and carrying on uninterrupted until you're back in civilization.

Ron

 

[jnfrombigt]

I wouldn't want to fly an airplane or sail a boat across an ocean with all my eggs in one basket. That doesn't really apply to vehicles since running out of gas is careless, not something that happens unexpectedly. It's a different situation when I'm boondocking. Lose a battery with dual batteries, flip a switch and carrying on uninterrupted until you're back in civilization.

Ron

Ten minute low fuel light comes on or main hydraulic light illuminates nice to have a backup. Even better a backup for the backup

 

[LSmith]

I just carry an inverter that I can connect to my truck electrical system so I can just plug the trailer in (with no other loads on it) and let the converter charge the batteries. This is an emergency backup only that I have not needed so far, but I have tested it and it works.

 

[tom&pam]

What inverter do you carry? It worked that once, so I suppose you are satisfied with it. Brand? Model number? Amps or watts available when needed?

 

[LSmith]

What inverter do you carry? It worked that once, so I suppose you are satisfied with it. Brand? Model number? Amps or watts available when needed?

It is a BESTEK 1000W pure sine wave inverter, and I keep it as plan B until it gives me a reason not to. For the test I ran the battery down to about 60%. If memory serves, the 120vac draw was less than 3 amps.

 

[John in Santa Cruz]

It is a BESTEK 1000W pure sine wave inverter, and I keep it as plan B until it gives me a reason not to. For the test I ran the battery down to about 60%. If memory serves, the 120vac draw was less than 3 amps.

how do you have that inverter wired to your truck's power? A 1000W inverter probably needs about 80 amps at 12V although Bestek has no specs on that on their website. 80 amps DC needs like AWG 4 gauge wiring. FWIW, the PD4655L converter/charger in my lithium packed Escape will draw about 700W AC when its charging the batteries (which charge at about 50A at 14 volts DC)

 

[LSmith]

how do you have that inverter wired to your truck's power? A 1000W inverter probably needs about 80 amps at 12V although Bestek has no specs on that on their website. 80 amps DC needs like AWG 4 gauge wiring. FWIW, the PD4655L converter/charger in my lithium packed Escape will draw about 700W AC when its charging the batteries (which charge at about 50A at 14 volts DC)

Right now I just use a set of small c-clamps to attach the inverter input leads to the truck. I plan on installing a permanent pigtail that I can more easily attach to. I forget what the input lead size I am using, but they are at least 4 awg and probably larger. They are also quite short. The inverter just sits in the engine bay with the hood up. You make a good point. Everything should be sized for the load you will be supplying. My battery bank is smaller and so is the converter.

 

[John in Santa Cruz]

Right now I just use a set of small c-clamps to attach the inverter input leads to the truck. I plan on installing a permanent pigtail that I can more easily attach to. I forget what the input lead size I am using, but they are at least 4 awg and probably larger. They are also quite short. The inverter just sits in the engine bay with the hood up. You make a good point. Everything should be sized for the load you will be supplying. My battery bank is smaller and so is the converter.

oooh, I thought you had this rigged so it could charge while you're driving. my mistake.

 

[Radar1]

DanandDaphne, I thought about a dual fuel generator. A lot of reviews say they are hard or impossible to start on LP and I do not want to carry a gasoline can. What is the secret? Champion seems to be a good brand.

I have a AIPower 2300/1800 watt gas generator that would not start my Dometic Penguin A/C. The starting amps caused the voltage to drop too much, and that's with a hard start kit installed.
I recently purchased a Wen 3600/2900 (gas) or 3500/2600 (propane) dual fuel generator that runs the A/C with no problems at slightly less than half load on propane. I don't plan to use gas in this one. Starts easily on propane as long as I remember to turn the gas valve on.