On our trip south this year our 8 year old Optima batteries lost a lot of capacity when we dry camped and after testing them when we got set up for the winter I gave them a load test and they are definitely not up to the job. I ordered two Li Time 100AH lithium batteries, Power Dynamics PD9160ALV converter for lithium batteries and a 20 amp Renogy DC to DC charger to increase the trucks 12V charging voltage for the lithium batteries.

I've done 2 load tests and I'm amazed at how long they last and how fast they recharge, the last test was over 24 hours running all the 12v in the trailer and our chest freezer off the inverter. After the 24 hours they still had 50% capacity and recharged in 2 hours. So far I'm very happy with the decision to make the switch, I may install some solar in the future time will tell. We have a built-in 5KW gas generator to charge the to them if needed but because of the charging rate I don't think our little Honda that I used to plug the old converter into won't handle to he load.

Denny

 

LFP chemistry is pretty amazing for sure. Not sure on the size of your Honda generator but my EU2000I or EU2000I handlles charging my batteries at 100ah.

Come this April it will be 8 years my 500ah LFP batteries have been in everday use running whatever appliances in the 5th wheel. I'll put some #s for that period of time in my NF trip thread in April. I recorded just about that entire time with solar production and battery use.

A little solar can go along way.

 

It is amazing what the LifePo4 batteries can do. My batteries are 304ah and they can be charged at 1c [that means at a 300ah level]. That is a lot of current! Try that on a lead acid battery........well, never try that on a lead acid battery.

I read about some battery technology that will accept a 4c charge. That means if a 300ah battery could be charged at 1200ah and would take 15 minutes to charge vs an hour for what I got.

I've got over 600ah now in my 5th wheel and another 300ah sitting in my shop waiting to be installed. The converter I have is rated to 100amps and maybe I will get two in the future. Just to speed up the time between charges.

 

I only went with two batteries because of the room in the battery compartment but after we get back home I'm thinking of adding one more after I modify the battery tray, that will be easier when I have my shop to do the modifications. The 60 amp converter should have no problem handling 3 batteries.

Denny

 

My Honda is a very old 650 watt none inverter, I've been running it at full load for years and it just won't die but I will give it a try.

Denny

 

The bigger the generator, the faster the charge. That is about the only advantage.

Even a charger/converter for a lead acid battery will charge lithium. I know about the opinions that are on the internet, but I have actually tested this 'theory' using my old original RV 55w converter and it charged my lithium battery to about 90%. Yes, it did take a bit long on the end, but it did charge them up. The rumor about only charging them to about 60% is just that. I'm confident that anyone that has time should charge their lithium batteries and see what happens. Remember, when the current stops, that is when the charger/converter will not do any more.

 

My GBS batteries can accept up to 3C continuous current for charging and discharging with up to 10C impulse discharging current. Even though my batteries have never seen a charge greater than .26C but have seen discharges of .4C.

Not many with larger LFP battery banks on rv's have the means to charge in a high C rate.

 

If I set the incoming AC to 18a while using the Eu2200i it will work that generator hard maxing the the charge 125a. Incoming 15a is the sweet spot for the generator and 100a steady charge rate.

 

I do have a backup for my little generator and that's my 5KW built-in that will charge them at full rate but the little one is a lot more fuel efficient. From what I've learned so far that when we stop for the night and dry camp it won't take to long to fully charge them were it to hours to charge the AGMs. It's going to be interesting relearning how to manage our batteries when traveling, we do have a residential refrigerator and chest freezer to keep cooled and frozen plus we like use the satellite TV when stopped.

Denny

 

Yes indeed, I suspect any factory converter/charger is not much more than 55A, unless you are talking about really big ones. When I was looking to upgrade mine when I swapped out the batteries, I did not see any above 120A. The only reason to get something bigger is to charge them faster. The normal 12V consumers probably don't take much more than 40A if everything is on. Just my guess.

Both of my BMS's are rated to 200A. I do have a 3k inverter and I have never used all of that. I have run the A/C for a few hours just to see what would happen, nothing exploded or caught fire. 4/0 cables were plenty cool.

 

Question for you guys that have converted. Did you also purchase a DC-DC charger for the truck to RV charging? So your truck can charge your RV lithium at the 14.6v recommended charge voltage? Just curious. I know that the truck will be able to charge it, but, it won't charge the RV lithium to 100% while traveling. Right?

 

Yes I installed a 20 amp charger, didn't want to overload the trucks and trailer wiring.

Denny

 

The first and last 10% of the battery really has very capacity. The middle is where all the storage is at. So, even if you can only get the battery to 95%, you are only loosing about 1-2% capacity.

Although, I do plan on installing a DC/DC charger, it's only because where my alternator is on my truck is a fair distance to the 5th wheel batteries. The voltage drop is fairly large no matter what gauge wire you are running.

 

I'm looking at putting a 560ah LiFePo battery on our trailer, my plan for charging on the road is the new Victron Buckboost B2B & upgrading the alternator to something like the MechMan or Leece Neville 230a, the advantage of this is apart from the increased amps available, they are 100% duty cycle rated, for comparison a stock alternator is only 30% duty cycle.

 

Solar does charge going down the road also.