I'm getting a new 33' Genesis toy hauler and it comes with two 100ah lithium batteries in it. How will my 2019 F350 handle the charging of these batteries? Is there something that needs to be done for it to work? Thanks.

 

I use a 20 amp DC to DC charger mounted close to the trailer batteries. I can keep the batteries (3 100 AH) charged running down the road with a residential frig and freezer running. Some use a bigger charger and a separate line running from the truck to the trailer.
Denny

 

You'll need to see if your new RV comes with a DC to DC charger or not - it's the best way to charge lithium batteries. I haven't really been looking at newer RVs so I can't actually say if any of them DO come with a charger already built in, but they should.

Personally I don't dry camp without a generator, so lithium batteries aren't a worthwhile upgrade for me. As long as the coach batteries are in good shape, they'll keep the heat running at about 55° while I'm out in the woods hunting, and I fire the generator up before I go inside and turn the heat up.

 

I suspect each of the LifePo4 batteries can take a 50A charge [100A total].. So, for maximum efficiency, you need cabling to handle that. The alternator may not like to provide that load too so that is something t look into.

Many people use a DC/DC charger, but you still need cabling in the truck to provide that much current to the rear of the truck. That won't be cheap. I would not run a cable less than 50A. I would save some money by using the truck frame as the ground circuit. Anderson connectors are something to look into. A DC/DC charger rated to at least 50A. I would try and use the alternator output lug if there was room. You could use a circuit breaker, at the beginning of the circuit, but don't get those cheap Chinese ones. They are junk. An old school fuse can work.

Check the local boat supply store. They have lots of good stuff that is safe to use. Bring money.

I have 1200ah of LifePo4 batteries and I have not got my truck battery charging system hooked up yet. At this time, I will have a second alternator dedicated to that duty. I figured since the air injection pump is not working, I could butcher an alternator in that spot. I've got a 408 build going on at this time.

 

Victron orian xs 12/12 50. Mount it preferably near your battery, but you'll need to intercept the charge wire off your 7 pin. In the victron app limit the incoming current to 10 or so amps. Depending on your truck, I went on the safe side at 10a. Spend the money on the xs so in the future if you want more charging you can wire from you truck battery through an Anderson and charge up to 50a.
Unless I'm running air conditioning off the batteries 10a has been plenty in my experience. I personally wouldn't even attempt more than 20a on the 7 pin.

 

Also, first find out if it has a DC to DC charger factory as said before. It is extremely screwed up if they equip a unit with lithium batteries without one...

 

The whole RV industry is a cluster ***** so don't be surprised....

 

Thanks for the input Guys. I appreciate it. I ended up opting for the AGM batteries.

 

As it has already been mentioned, the RV industry is making products to sell. Until the market demands good stuff, they will only offer junk that we are willing to buy. They are no worse than the cheap Chinese products that are offered. I think we Americans just like to complain about and blame things on someone else.

Not that I stand up for the RV industry, my understanding is that the dealer is the one that puts in the batteries. The manufacturer has no real say what goes in. Even if the manufacturer did put in lithium batteries, why would they put in a DC/DC charger? They should have a converter that charges the battery when you are plugged in on shore power. I do not recall any 9 pin cord that can handle much more than a trickle charge to the battery. The wiring is too long and small to handle much more than a few amps. A DC/DC charger will not be any help if the current going to the unit can't handle much more than a 9 pin connector can deliver.

A D/C/DC charger is an ideal way to charge the lithium batteries with the truck, but it takes a lot of copper and a good design for it to be any benefit.

 

For what it's worth, I didn't install a DC-DC charger. I left everything OEM. Now, does it completely 100% charge my Lifepo's while traveling? Nope. Don't care really. Not a lot is pulling off them while we're traveling down the road. 1 residential fridge and 1 small compact beer fridge. I do have solar as well which helps. On one trip, we traveled for 12 hours and I still had over 80% left in the Lifepo's. I'm sure the size of them makes a difference. I have (2) 280AH. And usually when I get to our destination, I plug into commercial power for at least 12 hours.

 

Hooked up to the 7-pin our LiFePO4s only charge at 40-50 watts. I plan to have a DC-DC charger installed, using the power from the 7-pin. I don't need 50 amps, even just 10 would be a whole lot better than what I've got right now. We also have 300w (theoretical) of solar and plan to at least double it - equinox level sun at 42°N it currently puts out around 180w in full sun which I think is pretty good.

 

Weird. I have a compact residential fridge and a full size beer fridge. What kind of camping do you do?

We all have different demands, when it's time, I would love to charge my 5th wheel while driving. I did swap my original 55A converter to a 125A converter. My goal was to full charge my batteries ASAP while plugged in. I have 1200ah so the charging time has been cut in half compared to the stock converter.

 

 

While sorta intended for the marine/ boat crowd, there is a device that allows for the perfect charging profile of LiFePo4 batteries and the creation of a Lead & Lithium hybrid battery bank that all plays nice together. Its called the battery bank manager (see link below to what I'm talking about)

https://marinedcac.com/?srsltid=AfmB...7Yi8s_cQXEfm-f

I've had one of these installed on my camper for the last year at least (maybe two years now), works fanatically well. Allows me to keep a big lead acid battery on the tongue for extra capacity and to use for the emergency brake break-away system. But really, the best thing is it allows me to charge the LiFePo4 batteries with basic battery chargers meant for lead acid battery chemistry.

I have solar on the roof of the camper, and of course the regular on-board charger for when I'm plugged in at the campground, and it can charge off my truck when towing. I also have a 3K watt inverter in the camper that I leave on powering the AC systems while driving because the genius manufacturer that put a second small refrigerator in my outdoor kitchen area put an AC powered one there (the normal inside fridge is DC powered).

The inverter and LiFePo4 batteries keep the little fridge in the outdoor kitchen area cold while moving and allow me to turn on one roof AC while hooking up (to start cooling down the inside for the wife, kids and dogs) . Once I'm all hooked up I switch over from inverter to campground power and the onboard charger (via the battery bank manger) charges the LiFePo4's back up using the perfect charging profile.

I'm not a boat guy, but it sure seems that the boat guys have battery power management down a little better than us camper guys.
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We are plugged in 90% of the time. So, we rarely see 50% or less battery capacity.