Hi,
Currently I use 2 6-volt batteries in series. One has "ruptured" or expanded thereby separating the top casing by about 1/8" Time to make a change.
Because I solar charge, I don't think I need the capacity anymore.

So my thoughts

1) 12 volt AGM- that would be simple
2) Li Phosphate... I could really benefit from the weight saving on the hitch.

Before I Google my brains out, looking for any real work experiences, any changes to the charging methods from the truck, etc. I have no problems charging the battery when stationary (at least I don't think I do)

Cheers!

 

LifePO4 batteries CONS Price (but this is changing). Potential for issues charging and discharging on extreme weather conditions (too cold and too hot). Older and most state of the art travel trailer converters do not have the correct charging profile so a charger that can maximize charging is recommended potentially adding to cost of the upgrade. a WFCO 8955 can get a LiFePO4 battery to about 90% SOC.

LifePO4 batteries PROS Lighter weight per Amp Hour, faster charging to full capacity especially on solar. Can take a deeper discharge down to 10% SOC without shortening the life of the battery. Not as subject to the Peukert effect so you can get more out of the battery bank. They don't require venting during charging as they do not off gas Hydrogen gas like Golf cart batteries.

2 6 volt GC2 batteries is typically 210-235 or so amp hrs in configuration meaning approximately 105-115 usable amp hrs since it's best for the longevity of the battery to keep them at 50% state of charge or better. and it can take several hours to charge to 100% SOC much of that in the absorption phase squeezing in that last 5-10% of usable amps. 100 Amp hr LiFePO4 battery can go as low as 10% SOC without significantly shortening the life of the battery so you have more usable amps and these can be recharge in a little bit more than half the time as the batteries don't need to sit on absorb forever to get that last 5-10%

IMO it boils down to this:
If relying on batteries (boondocking/dry camping or off grid) Then it may be a worthwhile expenditure. The biggest difference I can see regarding price for LifFePO4 batteries is the warranty Battle Born charges the most but stands behind their batteries with a 10 yr warranty. In general, the higher the cost, the better the warranty. You can build your own LiFePO4 battery for less than comparable AGM battery (but no warranty) There are plenty of how to video on You tube. Newer batteries can also be purchased with internal battery warmers to get past cold weather charging issues.

If spending your time at full or electric hook up RV Resorts (parking lots?) then the cost of the upgrade i most likely not worth it as you only enough battery to keep things running when your on the road. Get an reasonably inexpensive Group 31 AGM battery and leave it at that.

Only you can make the "Is it worth it" decision.

Personally, I am seriously considering a switch to LiFePO4 batteries on my next battery change which is still a few yrs out for me as I bought new batteries 3 yrs ago and have plenty of life in what I have so I can monitor pricing on the new technology. I prefer off grid boondocking and dry camping and would love to cut the weight on my battery bank (Currently 4 6 volt GC2 batteries) by 1/2 or more. I can get past the charging temp issues by placing the batteries in the unused storage area under my bed as the temp in the trailer is typically kept live-able and appropriate for LiFePO4 batteries. I'm looking into solar battery charging and all of the new setups have Lithium charging profiles. Additionally, I would love to NOT hear or smell my generator and have my batteries charge while I'm out hiking or kayaking or whatever and not sitting in or around the trailer waiting on the generator to top off the batteries. My current system can go 2 full days with liberal electric usage 3 days if limiting usage and paying attention we use our computer and TV quite a bit and my wife uses a blow dryer after washing her hair. (First world problem I know isn't it great?)

 

Thanks for the detailed response.

I only boondock, so being able to carry more water is a plus.

just wondering about the charging from the truck when enroute,any special considerations?

 

Well the nominal charge voltage I see online for LifePO4 batteries 14.4/14.6? volts or so. Check the output at your 7 pin and see what the voltage reads. (Probably not much above 13 due to wire size on the charging wire). Probably not enough to charge them fully I have seen recommendations for a DC-DC charging solution online to get the battery fully charged. Probably cheaper to install a solar charging system on the trailer.

Personally, I don't recommend relying on the tow vehicle to charge the house batteries of a travel trailer motoring down the road. Keep them from discharging certainly but charging 200+ amps of Deep cycle battery or a 100 Ah Lithium battery? That's not really the design or intent of the charging circuit especially since it is a single stage charge and not the three stage charging recommended for deep cycle Flooded Lead Acid batteries. IMO the charge wire in the seven pin is designed for a small sealed lead acid battery (5-7Ah) for emergency backup battery to apply the trailer brakes in a break away situation.

Just my opinion though.

 

I use a home built LifePo4 batteries in my trailer with a BMS in my trailer and while it works well on its own but it does not play nice with the F-150 trailer power system. LifePo4 batteries have a much different voltage curve (more of a cliff) and unless they are near dead the truck thinks they are fine and won't provide power.

I've tested this quite a few times. You follow the Ford method of hooking up for a full connection (engine off, connect trailer, close door, start engine, trailer recognized, power enabled). The problem is even with only half a charge the battery looks charged to the truck. So it pushes 3a for a bit sensing the status of the trailer, switches to 1a, and then powers off the link. Just like you would see from a smart charger without trickle support. The truck doesn't seem to sense status after it's done the initial probe because running the jack (6~10a draw) doesn't trigger the truck to provide assistance power.

I need to either find a way to make the truck provide charge when it doesn't think it needs to (FORScan spreadsheet doesn't seem to have that kind of option) or build an inline resistance adapter so the truck thinks the battery needs charge and will provide power on the link. With my on-board BMS I don't need to worry about the pack overcharging.

Frustrating with the truck being smarter than my needs.

 

Over the winter I got two Lion Energy 105 AH batteries while on Costco special. I also got a Victron Energy Multiplus 3000 inverter to run 120VAC for the fridge, microwave, coffee maker, laptop, LTE modem and TV. The inverter is overkill, I could have done nicely with a 2000 watt model but it wasn't much more to upsize it. So far I've only tried a couple nights on the inverter charging with my generator during the day. A two hour run seems to do it. I'd be willing to say I could go three days without a charge using this set up. Honestly I think solar charging is still too costly to be an effective solution, at least in my case. The batteries were $700 ea. sale price but I figure a 10 year life span. There are less costly alternatives showing on Amazon now too.

 

If you are boondocking a folding solar panel will keep your system charged for normal use (fans, lights, etc) but if you are using the inverter often you're right, solar won't keep up. My trailer uses about 0.9a/h just sitting with the fridge on (one of these days I'm going to see about getting that lower), so in the storage yard a basic solar panel keeps it topped off. I have 120ah of batteries so If it's cold and the heater running regularly I'm expecting to need the generator every two or three days to get the system charged back up again with the panel attached.

 

Cool info, I have been doing well keeping the golf cart batteries charged from solar...but I don't use much power. I use propane for the fridge...never consider electric...learn something new every day.
If I go LiPo, run the fridge on electric, thus getting rid of the 2- 7.5lb tanks for one 5 lb tank...I might have no tongue weight :-)

 

My fridge is dual (propane / AC power) but the controller is a constant drain on the DC system even when using propane for cooling.

 

I hear yah. My drain is I fly Electric RC airplanes ( since 1988) ...constantly charging those batteries. One would think I would have made jump to LiPO for the TT long ago but I thought fuel cells were going to be the answer...oops.
Also when towing with the F250 TW wasn't a concern....