Lithium Battery Advice

[High Road Travelers]

I know nothing about Lithium batteries, but on an upcoming trip I will be staying two nights and a day at a time without any hookups, and I currently have two 90 AH AGM batteries.
I am in a 2024 Brinkley Z3100 fifth wheel with one 370 watt Furrion solar panel, a Furrion solar charger and a 55 amp WFCO converter. I tow with a 2023 RAM 3500 dually. My refrigerator is a Furrion 12 volt 16 cu ft and will be the main electricity user, besides some LED lights and roof vent fans.
I believe (not 100% sure) that my converter will automatically detect battery type and the solar charger can be set to either battery type.
My question: What Lithium batteries (I assume I need two) do I need that will last this long. My batteries need to have a good charge to operate three electric slides and electric levelers. If the sun is shining I believe my solar panel should keep me charged during the day.
Also, I assume my truck should keep the batteries charged while traveling if the sun is not shining.
Any advice on what brand and size to get is appreciated. (I don't need the biggest and bestest - just good that will last a couple days and nights). Also do I need the type with heater for the winter; I will camp while below freezing a little bit.
Thanks,

[d23haynes57]

Originally Posted by High Road Travelers

I know nothing about Lithium batteries, but on an upcoming trip I will be staying two nights and a day at a time without any hookups, and I currently have two 90 AH AGM batteries.
I am in a 2024 Brinkley Z3100 fifth wheel with one 370 watt Furrion solar panel, a Furrion solar charger and a 55 amp WFCO converter. I tow with a 2023 RAM 3500 dually. My refrigerator is a Furrion 12 volt 16 cu ft and will be the main electricity user, besides some LED lights and roof vent fans.
I believe (not 100% sure) that my converter will automatically detect battery type and the solar charger can be set to either battery type.
My question: What Lithium batteries (I assume I need two) do I need that will last this long. My batteries need to have a good charge to operate three electric slides and electric levelers. If the sun is shining I believe my solar panel should keep me charged during the day.
Also, I assume my truck should keep the batteries charged while traveling if the sun is not shining.
Any advice on what brand and size to get is appreciated. (I don't need the biggest and bestest - just good that will last a couple days and nights). Also do I need the type with heater for the winter; I will camp while below freezing a little bit.
Thanks,

The first step to determine how much battery you need is to know how much power you need and for how long. A metering system. Do you have experience with your present set up? How many days can you go? Experiment while at home. Charge the batteries. Then unplug, turn on the fridge, use the lights or whatever else you need including the heater. See how long you go. Are you thinking an inverter in the future? Will you want AC power. Watch real TV, use a microwave?

Looking to upgrade batteries you need a complete approach including future demands. Generator may be part of the overall plan. Will you want AC? Looking for a battery now as this is not part of a vehicle, motor home system you really do not have barriers beyond space and Budget. 300 A/H batteries are now the current pricing sweet spot so I would begin there. Can you fit one, maybe 2. Your charger will somewhat work, maybe work well. A 300 A/H battery with a 200 amp BMS will future support up to a 2,000 watt inverter for short time needs TV and Microwave, coffee maker. A second battery would be ideal for 3,000 watt plus inverter which will run an AC. Some wiring is needed for a proper install. The two batteries 300 A/H each for a total 600 A/H bank and a 3,000 watt inverter/Charger with a 150 A/H charger section would be an ideal combination. More batteries can be added for more run time. A 3,000 watt generator would support this inverter/charger and also run the AC. 4,000 watt would be even better. The tow vehicle would need some charging equipment added to charge those batteries while driving. A dedicated charge line and either relay control or DC-DC charger. Alternator capacity has to be considered as part of that system design.

If you would like dedicated assistance with this OK to call or text, 631-897-0345.
You may also P-Mail. dennis-vw-service@outlook.com

Dennis

[Persistent]

staying two nights and a day at a time without any hookups
have two 90 AH AGM batteries. (12 volt? = 180 amp hours)
2024 Brinkley Z3100 fifth wheel
370 watt Furrion solar panel, a Furrion solar charger
2023 RAM 3500 dually.
refrigerator is a Furrion 12 volt 16 cu ft and will be the main electricity user, besides some LED lights and roof vent fans.
solar charger can be set to either Li or LB
55 amp WFCO converter. I believe (not 100% sure) that my converter will automatically detect battery type

WFCO auto detect have a "-AD" in the model number if they have auto detect. Some older models have a lithium switch. Post complete model number for better advice.

What Lithium batteries (I assume I need two) do I need that will last this long? My batteries need to have a good charge to operate three electric slides and electric levelers.

A few years ago most "drop-in" lithium RV batteries were 100 amp hours. Now they come in many capacities.

The most important shopping factor is that all lithium batteries are not the same. Carefully read all specifications for proposed lithium batteries not just the "marketing" hype.

You will probably need around 300 amp hours of capacity. 200 would be enough except for the electric refrigerator. I assume it is a compressor type. Compressor types are also not all the same. Some use more power than others. An additional 100 amp hours will probably cover the need.

That said, the power levelers and slides need special consideration. Not all trailer slide motors and levelers are the same. Some use very high current and draw sudden bursts of power when they start.

Lithium batteries have a BMS. It is an electrical device inside the battery case. Some can handle sudden starting loads and high current draw well. Some just fry the BMS. Carefully read the specifications for the battery, not just the marketing literature.

Light duty BMS cost less than heavy duty BMS.

If the sun is shining I believe my solar panel should keep me charged during the day.f

This works well in the desert Southwest. It does not work so well in Northern areas in the winter. It also does not work well in heavily forested areas or areas that have long periods of fog or cloud cover.

Also, I assume my truck should keep the batteries charged while traveling if the sun is not shining.

A tow vehicle may supply 30 amps for the time the engine is running. This will help add charge to deeply discharged lithium batteries. Unless you drive for many hours each day, it will not fully charge a deeply discharged lithium battery bank.

30a X 6hrs = 180 amp hours. Lithium requires 14.4 volts at least for the last hour or two. A tow vehicle alternator may not provide that high voltage for long periods.

A battery to battery charger with lithium charging profile will probably be needed to get the full 30 amps out of the tow vehicle system and to maintain 14.4 volts until the end of charging.

Any advice on what brand and size to get is appreciated. (I don't need the biggest and bestest - just good that will last a couple days and nights). Also do I need the type with heater for the winter; I will camp while below freezing a little bit.


The lithium batteries will need heat in order to charge when temperature is below 32 degrees. Temperature may need to be above 40 degrees if the BMS has disconnected due to low temperature.

Most RV lithium batteries can still discharge down to about -4 degrees. See battery instructions and specifications for temperature requirements.

Install them in a heated place inside the cabin for best boondocking experience. Battery heaters will be necessary if installed in unheated space.

An RV propane furnace for a 5th wheel trailer requires lots of 12 volt power. I would add another 100 amp hours to run the furnace for a couple of more days.

Solar plus driving will work together, but fixed angle mounted solar will probably not work well in Northern winter conditions. My 600 watt roof mounted system maxed out a 150 watts in Wisconsin in February.

Battery Capacity

If your current 180 amp hours of battery capacity is enough for your required 3 days in freeing weather, then you need the same capacity using lithium. If not, then see the following:

I recommend at least 400 amp hours of LiFePO4 lithium battery capacity for freezing weather camping. Make sure the battery BMS can supply the needed high current to run the levelers and slides.

As posted above there are some high capacity 300 amp hour batteries at good price points. Double check maximum current output the batteries supply and search instructions and specifications for cautions about running high current motors.

Tow Vehicle Charging

A 30 amp B to B (battery to battery) charger will be required to get maximum charging from the tow vehicle alternator. You can do without but will probably get lower and less complete charging.

A 400 amp hour lithium battery bank might blow tow vehicle fuse or trip circuit breaker if large size cable is used to make trailer to tow vehicle connections. A B to B charger will prevent that.

A 200 amp hour lithium battery bank will probably not blow a fuse.

WFCO -AD Charger

WFCO auto detect chargers will charge a 300 or 400 amp hour lithium battery bank. A 55 amp charger will take at least 8 hours to charge a depleted 400 amp hour battery bank.

The WFCO may be inconsistent as to how completely it will charge. The auto detect is not consistent in detecting lithium and may not complete the charge. Some charge cycles it will and some it won't. However, the solar controller will probably finish the charge just fine. The final half hour or so does not require high current. It just takes longer to finish.

For a 400 amp hour battery bank you may wish to get a 100 amp charger so it can be charged more quickly and completely. This especially true if you want to charge using a generator.

A 100 amp charger can cause delayed tripping of a 20 amp shore power circuit. Some 100 amp chargers can limit input to prevent tripping.

A 75 amp charger will probably not trip a 20 amp breaker and may work on a 15 amp breaker. It will just take longer to charge.

Victron is one of the best systems. It is complicated and expensive.
Progressive Dynamics is very good and simpler to configure and install.
GoPower is a lower price point system.

I recommend you install a shunt type 12 volt power monitor. The lead acid type monitoring system probably installed in your trailer will not work with lithium voltages.

Battery Brand

Better battery brands cost more. Often, the better brands offer expert help designing and building a system. Battle Born provides expert service. The planing and design evaluation can be free. A novice can avoid buying the wrong components and unnecessary failures using expert advice.

Use this search term to find many articles about designing and building a system:
"How to design an RV lithium battery system"

[Lantley]

I don't want to discourage you from going Lithium. However is this 2 day trip a rare occasion or is it something you plan to do regularly?
Going Lithium is ideal for those who go off grid regularly, but as you see above its not as simple as just swapping batteries. If you don't plan to go off grid regularly it may not be worth the trouble. Consider a small dual fuel generator. Running it a few hours a day maybe enough to keep batteries charged without reinventing the wheel.
Before you go all in on Lithium they maybe simpler options.

[d23haynes57]

Originally Posted by Lantley

I don't want to discourage you from going Lithium. However is this 2 day trip a rare occasion or is it something you plan to do regularly?
Going Lithium is ideal for those who go off grid regularly, but as you see above its not as simple as just swapping batteries. If you don't plan to go off grid regularly it may not be worth the trouble. Consider a small dual fuel generator. Running it a few hours a day maybe enough to keep batteries charged without reinventing the wheel.
Before you go all in on Lithium they maybe simpler options.

Why have a camper if it is not set up to do what you need or want it to do when you want to use it. A two-day trip should not be an event that needs questioning. Upgrades that make thing easier to use also tend to make them used more often. As for a lithium upgrade the cost is down and you just have to get past the noise of it being difficult. Reality is that charging lithium is much easier than lead acid, especially AGM or Gell and the internal BMS makes it almost fool proof.

[SafariBen]

Doesn't sound like you're doing this forever. How are your current batteries working? If you can park in the sun and/or tilt the panel, you should be fine as you have it now. If not, start the truck for half an hour in the morning for a little boost.



I agree to go with one bigger battery, and 300AH is a sweet spot right now, one 300AH will amaze you if your current batteries are getting tired.

[High Road Travelers]

Originally Posted by Persistent

WFCO auto detect have a "-AD" in the model number if they have auto detect. Some older models have a lithium switch. Post complete model number for better advice.

Mine is "AD", model #WF-9855-AD"

You will probably need around 300 amp hours of capacity. 200 would be enough except for the electric refrigerator. I assume it is a compressor type.
I have decided on a 300 amp so I do not need to change any other equipment. Fridge is a compressor type.

Lithium batteries have a BMS. It is an electrical device inside the battery case. Some can handle sudden starting loads and high current draw well. Some just fry the BMS. Carefully read the specifications for the battery, not just the marketing literature.

A tow vehicle may supply 30 amps for the time the engine is running. This will help add charge to deeply discharged lithium batteries. Unless you drive for many hours each day, it will not fully charge a deeply discharged lithium battery bank.

30a X 6hrs = 180 amp hours. Lithium requires 14.4 volts at least for the last hour or two. A tow vehicle alternator may not provide that high voltage for long periods.

A battery to battery charger with lithium charging profile will probably be needed to get the full 30 amps out of the tow vehicle system and to maintain 14.4 volts until the end of charging.

I would not rely on the truck to fully charge the batteries


The lithium batteries will need heat in order to charge when temperature is below 32 degrees. Temperature may need to be above 40 degrees if the BMS has disconnected due to low temperature.

Most RV lithium batteries can still discharge down to about -4 degrees. See battery instructions and specifications for temperature requirements.

Install them in a heated place inside the cabin for best boondocking experience. Battery heaters will be necessary if installed in unheated space.


I can install in a heated area.

Without spending a large amount, do you think this battery meets my needs and works with my current equipment?
https://www.amazon.com/Lifepo4-Batte...32&sr=8-3&th=1
Your response information is very much appreciated and most informative.
Thanks,

[d23haynes57]

I have no experience with this model or brand. For a basic install it should work fine.
The bluetooth app will allow you to manage it. You may just want to consider something more "available" so a match will be available if you decide to add one in the future.

[High Road Travelers]

Originally Posted by d23haynes57

I have no experience with this model or brand. For a basic install it should work fine.
The bluetooth app will allow you to manage it. You may just want to consider something more "available" so a match will be available if you decide to add one in the future.

Thanks and I appreciate that tip. I don't plan to expand from here, but if I did it would be a big expansion of solar, add a large inverter and much more battery power to be able to run air conditioning and everything on battery power. That's a heap big bunch of money that I just don't envision myself doing, but who knows what the future holds
Thanks,

[Persistent]

Originally Posted by High Road Travelers

Without spending a large amount, do you think this battery meets my needs and works with my current equipment?
https://www.amazon.com/Lifepo4-Batte...32&sr=8-3&th=1
Your response information is very much appreciated and most informative.
Thanks,

The marketing advertising suggests it will work for you. Price point is pretty good. The price is likely to go up in the near future given current economic situation. Elefast is Chinese, so the brand may shut down USA based support soon.

There appears to be no manual or detailed specifications posted on the internet for Elefast 300AH Lithium Battery. So, there is a failure risk.

The 300AH is a new one as far as I can see. There are a few references to a 100AH model, but specs do not always carry over. The BMS in the 300AH may be the same one as in the 100AH model. 200 amp maximum discharge with 50 amps recommended charging. A better 300AH battery would have a more robust BMS.

The Elefast is unlikely to blow a tow vehicle fuse, but I would keep a spare handy.

Drop it in. See if it works. It may have the Amazon 30 day guaranty. Support 5 years from now is unknown.

[Lantley]

Originally Posted by d23haynes57

Why have a camper if it is not set up to do what you need or want it to do when you want to use it. A two-day trip should not be an event that needs questioning. Upgrades that make thing easier to use also tend to make them used more often. As for a lithium upgrade the cost is down and you just have to get past the noise of it being difficult. Reality is that charging lithium is much easier than lead acid, especially AGM or Gell and the internal BMS makes it almost fool proof.

Slice it however you want a $500.00 lightweight dual fuel genset is also an upgrade that doesn't require any installation or alteration to the existing set up.
In some ways the genset is a more foolproof option to allow for off grid camping.
I'm not suggesting a genset is a better option vs. Lithium. But I am suggesting it is a viable option that is a simple versatile solution.

[Isaac-1]

While I love that I upgraded to LiFePo4 batteries about 3 years ago, I don't think it is worth it for 2 nights of dry camping if your current batteries are still good. On a simple monetary perspective, a good brand 200AH LiFePo4 battery will cost you about $500, something like a LiTime or Vatrer with bluetooth monitor. Or for the same money something like a little more mid range 300AH Ecoworthy with Bluetooth monitor. In an ideal world this would be a drop in replacement if your converter supports LiFePo4 charging, either officially, or if its specs are close enough. Note I suggest the Bluetooth models to save you $60-$100 on a battery charge monitor as you can't effectively use voltage to show charge level on Lithium batteries like you can with lead acid.


However if your batteries will still hold enough charge to get you through 24 hours, you could buy a small inverter generator from Harbor Freight, etc. for around $400 and charge them back up daily. Right now Harbor Freight has their current version of the Predator 1400 on Clearance for $429 https://www.harborfreight.com/1400-w...epa-71342.html

[Isaac-1]

Originally Posted by High Road Travelers

Without spending a large amount, do you think this battery meets my needs and works with my current equipment?
https://www.amazon.com/Lifepo4-Batte...32&sr=8-3&th=1
Your response information is very much appreciated and most informative.
Thanks,

I would spend $70 more and get a brand name people have heard before like this EcoWorthy https://www.amazon.com/ECO-WORTHY-Bl.../dp/B0DS3Y9TBQ it also has Bluetooth power level monitoring

[High Road Travelers]

I appreciate the advice and tips given and have successfully replaced my two 90 ah AGM batteries with one 330 ah Lithium battery. It was not without stress, and I did some research with a WFCO tech, and got some private message assistance from Persistent. However, it is working as planned with no further equipment changes. I do have a short distance from the battery to the 4/0 cable in the camper of 6 awg cable, and will change it to 4/0.
One thing the WFCO tech said was to discharge the new battery down to about 20%, then turn the rv charger on; and that helps the converter automatically detect that it is now charging a lithium battery. What I did not know is that my 55 amp WFCO model #9855-AD converter/charger will shut off after 4 hours of charging, and my battery needed about 7 hours of charging. So thought it was not working right until I found that tidbit of info. I unplugged shore power and plugged back up and it started charging again, and I breathed a sigh of relief. The charger did automatically detect the lithium battery also.
My 50 amp solar controller just needed to be manually set to lithium, and it is working properly.
If I had known what I was doing, this process would have been just a simple swap of batteries and a manual setting on the solar controller. However, I had not even seen a lithium battery before, so I learned something.
And now on my upcoming trip to CO, WY, MT and SD; I don't need to worry if I decide to stop somewhere real nice for 2 or 3 days. I will have enough battery power to keep the 12 volt fridge running and bring my slides in and use my levelers to hookup when I get ready to leave.
As a note I bought a Elefast 330 ah battery with a bluetooth 200 amp BMS for $390 from Amazon. Note that I am not promoting this battery as I know nothing about their quality. I think it will meet my simple needs and I probably won't be able to travel but for another 3 or 4 years or so before I wear out.
Thanks,