Boondocking on lithium batteries?

[klash]

We upgraded to lithium batteries on our 25ft Globetrotter and would like to boondock for a couple of nights without hookups or generator. Will the lithiums last 2 nights/3 days? We plan on running the furnace and watching tV.
Thanks!

[foobar]

Originally Posted by klash

We upgraded to lithium batteries on our 25ft Globetrotter and would like to boondock for a couple of nights without hookups or generator. Will the lithiums last 2 nights/3 days? We plan on running the furnace and watching tV.

Thanks!

That is a tough question to answer without additional information.

What is the total amp hour rating of your lithium batteries?

What is the power (wattage) of each appliance you plan on using? And how long will you operate each appliance?

Do you have solar panels? If so, what is the total wattage?

[jeffb831]

Originally Posted by klash

We upgraded to lithium batteries on our 25ft Globetrotter and would like to boondock for a couple of nights without hookups or generator. Will the lithiums last 2 nights/3 days? We plan on running the furnace and watching tV.
Thanks!

It should work OK but it will be close and is dependent on a few things:

• How large are the batteries?
• Do you have an electric or propane refrigerator? Electric only will consume about 50Ah / day
• Do you have any solar? If not, I'd consider getting at least a portable panel to recharge during the day.

[pteck]

As part of your lithium battery upgrade, I would suggest adding a shunt based battery monitor that shows live power usage and state of charge / Ah reserve.

Most of these meters will also show remaining time at current draw levels.

https://a.co/d/7bwtsSl

That should be able to answer your question as to whether you can make a weekend.

That said, many get caught up in lithium as a power solution. It's not. It's only reserve, just as the original batteries were. They may have more capacity but that depends on how much was installed.

The real answer to boondocking is solar. That will add a real source of power creation, that can potentially create a perpetual power source.

If you don't have solar, there are many portable panels that can be easily plugged in to augment or extend usable power.

[richard5933]

So many variables it's really difficult to give an answer. Everything from how cold it is outside to how much your inverter/TV draws from the batteries are unknowns, and they will play a big part in determining how long your batteries last.

Do you have any solar? Maybe a portable panel?

[ts8501]

Also consider time of year for solar. I am harvesting way less energy in September than I was in June (I’m close to the 45th parallel). I have three 90 watt panels on my roof, and a portable 180, for a total of 450 watts. Two 100ah lithiums for battery storage. On cloudy conditions, I could not sustain for two days when using the inverter for watching TV. But as stated before, there are many variables to consider.

[Wazbro]

Try it in your yard or a campground. That way you can plug in and charge when the batteries go dead.

[Jcondon]

I would bring a small generator to charge if needed. I use a Honda EU1000.

[foobar]

Originally Posted by Jcondon

I would bring a small generator to charge if needed. I use a Honda EU1000.

Another benefit of lithium batteries is that they can charge at max rate until nearly full vs lead acid batteries that can only be charged to 70% or so, then require hours of charging at a slow rate to reach a fully charged status.

The net result has two benefits that favor lithium batteries. Generator run time is much less when charging lithium batteries and therefore generator fuel consumption is also much less.

[wineteam]

I have lithium batteries and five 90w solar panels which made me think I was Superman. I could run almost anything for as long as I wanted. One time boondocking the AS trailer next to ours asked if the sound she heard was our furnace running at night. Yes it was. She was surprised as she couldn't do that on her AGM batteries. Next night we ran the furnace too. In the morning I get up to adjust the thermostat and nada. No digital readout. I was incredulous as I thought I was electrical Superman. Nope, my lithium batteries were down to 10.47V. I couldn't even get range to let propane out to boil water for coffee. I had to use my outdoor bbq to heat the water.
In reality we were in partial shade and had plenty of power if we used it wisely. In the end it was a great learning lesson. I know more about my system now than previously. I have added the Camo Wave 6 catalytic heater so I don't need to use the furnace as the furnace blower does use a fair amount of watts. If I keep an eye on my volts, watts generated from the solar, and understand how much each component draws, we can boondock successfully for long periods of time. If you can learn the limits of your system before boondocking, you will have a successful trip.
Happy Camping!

[Rosey Jet]

We can go with furnace set a low temp and being careful with appliances, fridge on propane, indefinitely (7 days) as long as there is full sun exposure every day. We have a generator but have not plugged into trailer once since purchasing. Disconnect from tow vehicle just in case you have to, dead TV due to trailer drain is an issue we have with a rental several years ago.

[99TJSE]

We have a 27 GT, and boondock a lot. We also full time here in the Pacific Northwest. Trees, clouds, canyons, etc.

The GT currently has 2 x 206 amp hour LiFePO4 SOK batteries. Those will run us off grid for three nights and four days. We don't watch TV though, so there's that. We're also adding an additional SOK for a total of 618 amp hours.

On the charging side of things...

One portable 200 watt solar panel that rarely runs above 25-30% efficiency because of local conditions. The TV can add some minor charge while driving. It was never designed or intended for lithium though. The stock converter pumps an average of about 25 amps into the batteries. That's lower than it's rated for, but within what the stock wiring will handle.

Our best bet for charging is a small generator through the converter that we run for a few hours every couple of days.

There's a lot more to boondocking electrical supply than dropping in a couple of lithium batteries and rocking out for a few days.

[uncle_bob]

Hi

As others have mentioned, there are a *lot* of variables.

Guess one: you have 200AH of lithium battery.

Guess two: you don't have a DC/DC converter to charge while towing.

Guess three: you will. be out in sub freezing temps, at least at night.

Guess four: part of the group likes inside temps above 60F, even at night.

Guess five: no solar or very little solar

Guess six: It's in the 40's during the day and <60F isn't going to cut it then either

Could all of those be correct? If so, I should go buy a couple lottery tickets . Could none of them be correct? Yup, nobody does things quite the same way.

So the math: 3 days of furnace heating by (maybe) 20 degrees. Solar gain will help here (hopefully). Two nights of furnace heating by (likely) 40 degrees most of the night.

Just for grins, lets say the furnace averages 2AH an hour daytime and 6AH an hour at night. Same guesswork going on. 12 x 3 x 2 = 72AH for the day. 12 x 2 x 6 = 144 AH for the night. We have a problem ....

Change the guesses and the math changes.

Maybe night is 8 hours. 8 x 2 x 6 =96. Maybe there's no heat for 4 hours. on 2 days. You now are at 168 AH out of 200. You now have 32AH to run the TV, water pump, lights, and all the other stuff.

All that other stuff / the water pump etc, gets back to just how much you use *without* the furnace. If that's 30AH a day, your three days gets to 90AH. If it's 60AH a day, you are at 180AH without any furnace.

As noted above, a shunt based monitor is *very* useful when these questions come up.

Bob

[jimdelane]

Best way to figure it out is to install and configure a Victron battery monitor. Turn off all charging components. Turn on all the stuff you plan to have running when boondocking and see what the 'time remaining" is. If you have solar, you can turn off all discharging, then look at the monitor and get an idea of what your power input is. Between the 2 you should be able to estimate have long you can boondock.

[Troutboy]

We boondock a lot. Have a 23D Flyingcloud. 300 amp hour of lithium. 500w solar on roof. Camp in Colorado through October. It gets cold at night in the fall. 30’s and 40’sF.

At night with heat on 70 we lose 8-10% of our battery from furnace. During the day we lose maybe 5% from fans, electronics, (no microwave), targeted inverter use (not leaving on all day).

We are very careful and manage the electricity use (turn off lights etc). Without any solar, we could last 5-6 days with no charging. 4 for sure. With solar, it’s sunny in Colorado, usually by noon we get back to 100% by noon. When weather is bad (rain,clouds) we get 5-10% back. And can go longer.

You can run your own tests. Play around etc. as others said it depends on your systems, capacities, use patterns, trailer size, etc. the best way is to use your stuff and pay attention. I have owned own the unit for 5 years and had no idea what to expect at first. But going out and trying new things and paying attention, I now feel I know it well, what it will do, how long water lasts under what conditions and power. Have fun with it and learn!

[foobar]

Suggestions:

Install a battery shunt/monitor along with the lithium and solar upgrade.

Then go camping at a full hookup RV campground, but "don't" hookup.

Then you can play around with turning on each electrical load one at a time and see what the current draw from the battery is. Current draw multiplied by the length of time (measured in units of hours) gives the amp-hr cost of running that appliance. You can add up all of the amp hours you think you will consume and compare it to your battery capacity. If you burn 100ah in a 24hr period and you have 200ah of lithium (and are willing to charge the batteries up to 100% and discharge to 0%), then you can last 2 days without solar or charging from batteries.

The reason for doing all of this experimentation at a full hookup is that you can try to "boondock" and see how long your typical trailer usage will last in terms of battery capacity, then you can connect up to the power pedestal and recharge without ruining your camping trip by running out of juice :-)

If you are willing to do a little research up front, you can determine your expected amp-hour usage before you upgrade and can use that information along with the length of time you would like to boondock in order to determine how much solar you will need to install as part of your upgrade package along with the required battery bank size (in terms of amp-hour capacity).

[pteck]

Amen to the power monitor so one can objectively understand their usage and modify their consumption as necessary.

Beyond that, part of what we're all getting at is that for boondocking, there needs to be power sources. At least for extended days, heavier electricity usage, or in lieu of enough reserve.

Reserve is good and lithium (LiFePO4s) are the best for that. Yet they don't create power and ultimately will run out. Maybe one can eek out a weekend, but there's limitations. Even the largest batts, when on a power binge using furnace, entertainment, what-have-you, can be drawn down.

Power sources, and varied power sources for the situation may be the best answer.
1) Solar, either installed or portable
2) DC-DC charging capability from the tow vehicle
3) Generator, if one must, though I don't really care for this as a source these days

Outside of the box
4) Larger DC-DC charging capability from the tow vehicle. To @foobar's point, it's possible with lithiums to charge faster, when combined with a larger DC-DC charger, can push some serious amp into the trailer with minimal idling time
5) Portable lithium battery, aka solar generator - these are super flexible. I have 400Ah LiFePO4 installed in the trailer. I keep a 100Ah Goal Zero battery alongside. I can easily put it on a camping table for blender, or other use case. Lend to a friends trailer. Bring to the TV when we go a couple days into the backcountry without the trailer. It's also perfect as backup. I can charge it anywhere there's an outlet, or on the TV as we explore during the day. I can bring it back to the trailer to bolster the energy there via the 120V outlet to converter. A lot of flexibility.
6) I also have a 100Ah LiFePO4 dual battery/house battery on my TV. It's charged anytime I drive the car and tends to stay pretty charged. I can charge transfer the power to the trailer batts by just plugging in an Anderson, while the car is either on or off.

[tusocks]

We will be receiving our 2023 27 GT in two months and was hoping to install 2 SOKs batteries. Originally I thought about installing two of the 100 Ah batteries but there is no way that they will fit into the battery box that comes from the factory. Therefore I was thinking about installing two of the 206 Ah batteries and I assume that you installed those in the baggage compartment that is directly behind the battery box on the outside of the trailer. Is that correct?
Two other questions: have you had much “wobble” in your dinette table and if so have you done anything to try to lessen that question? Also, how is the 27 GT been working out for you?
Thanking you in advance for your response
Mark & Jeannie

[Troutboy]

Has anyone tried this. Interesting concept. Use your tow vehicle as a backup generator…

https://www.cargenerator.com/

[uncle_bob]

Originally Posted by tusocks

We will be receiving our 2023 27 GT in two months and was hoping to install 2 SOKs batteries. Originally I thought about installing two of the 100 Ah batteries but there is no way that they will fit into the battery box that comes from the factory. Therefore I was thinking about installing two of the 206 Ah batteries and I assume that you installed those in the baggage compartment that is directly behind the battery box on the outside of the trailer. Is that correct?
Two other questions: have you had much “wobble” in your dinette table and if so have you done anything to try to lessen that question? Also, how is the 27 GT been working out for you?
Thanking you in advance for your response
Mark & Jeannie

Hi

I believe you will find that there are a number of 100AH lithium batteries that fit in the factory battery box. No, you aren't going to get more than 200AH of lithium in there. If you are after 400AH or more, it's gotta go someplace else ( or at least part of it does).

There are a *lot* of choices about where to put lithiums. Since they don't have the venting issues that lead acid's do, they can go just about anywhere. Under this or under that, it all seems to work. We have 200AH under the center of the sofa in the Classic.

On a 2023 you will have a compressor fridge. They pull a non-trivial amount of power. It goes out while you are towing as well as when you are camping. Unless you put in a DC / DC converter for charging while towing, the "on route" power drain gets added to your drain at the campsite.

Some math:

If the fridge averages 3.5 AH an hour ( who knows ...) then you run 24 x 3.5 = 84 AH a day running the fridge. In 5 days, the fridge all by itself kills 400AH of batteries.

If you drive 4 hours a day and charge at 10A while doing so, you get 40AH a day back from the drive. You can now drive for almost 10 days before the fridge by itself kills your 400AH of battery.

Yes, this all is part of why many of us run solar .....

Bob