Swithcing to Li-ion, please help me be lazy

[smithcreek]

After sending my AGM's to their well deserved big sleep, I am finally making the change over to Li-ion and I am looking to the "far more knowledgeable than myself" forum members to guide me in this process. In other words, help me be lazy, tell me what I need, and make some recommendations for products!

The trailer is a 2013 FB20. The electrical system is all original equipment. I have to tools and ability and plan to do the work myself. The trailer is still going to be used mainly for weekend trips and occasional longer ones, but anything over 3-4 days I'll probably be looking for hookups, so I don't need a huge amount of storage and at this point I'm not looking to get into a solar array. I have a portable panel and will stick with that when needed.

My main goal would be to get through a 3-day weekend without worrying too much about running out of juice and whether my portable solar panel was going to keep me charged. I still plan on being frugal with power use, not looking to watch TV or run a microwave, just want to use the lights, the propane fridge, water pump, charge phones, and maybe the stereo.

What other info can I provide to help with recommendations?

[waninae39]

IMHO, look into victron energy systems. These are the best and most reliable products to use

[JeffKim]

The lithium battery rabbit hole is large and deep, but at a minimum you will need:

1. Batteries
2. Lithium compatible charger
3. Charge monitor

There are a ton of batteries out there, but a lot of people with Airstreams recently like the Epoch 300Ah. Typically you can only get two 100Ah standard sized batteries in the battery box, but the Epoch apparently fits. This thread has a lot of useful information. If you go with a 300Ah battery you should be able to camp for a very long time without plugging in. Over two 100Ah lead-acid batteries that's about 3x the capacity (with lead-acid limited to 50% discharge).

Your charger works for lead-acid but not lithium which requires a higher voltage and different staging to balance the cells. I have a Victron IP43 Phoenix Smart 50A charger which is fabulous but it doesn't fit in the converter box. Other models such as Progressive Dynamics I think will fit. Or there are the Victron IP22 30A models but I'm not sure they are meant for heavy duty.

It's next to impossible to judge the state of charge of a lithium battery by the voltage. Epoch and other models have Bluetooth monitoring. Or you can install something like a Victron shunt in the battery box. I have the shunt and like it since it plays with all my other Victron equipment giving the charger an accurate reading at the battery so it can account for voltage drop in the wiring.

In addition, some sort of battery cutoff switch is a good idea. This will isolate the batteries and makes winter storage a lot easier. Also be mindful of the fusing. Your old batteries likely have a MRBF fuse on them. This will work for lithium too. Type-T fuses are even better since lithium can discharge a lot of current if shorted out.

[tominphx]

First thing I would do is an energy audit, you'll need to know what your energy usage is.
That needs to be done on both the 12V and 120V side of things, once you do that, you will be able to determine the size of your battery/batteries. You will also need to know if your inverter is LiFePO4 compatible if not you'll need a new one that is. Victron equipment is the gold standard but expensive, there are reasonably priced alternatives. Same goes with Battle Born Batteries, good but expensive, the battery segment is flooded with Chinese batteries that are for the most part of high quality and much less expensive. You will have to do a bit of research on BMS (battery management systems) and what features you may be in need of. I would assume that your solar panel is regulated (has its own charge controller) and you use the trailers Zamp port to charge, if not a new charge controller will be needed.

Cheers, Tom

[JeffKim]

...forgot to add. Don't get the WFCO AD charger, it's supposed to autodetect battery type, but it's a PIA and doesn't work very well.

Check your external panel controller for a lithium setting. If it doesn't have one then you'll need one for lithium. I advocate mounting it inside the trailer and wiring the Zamp plug in (if you have one) to it. Something like a Victron 75|15 would work for your panel.

[smithcreek]

I did a quick and dirty energy audit, 300Ah should be more than enough for what I need, and I like the look of the Epoch battery. I can weld if I need to, but it looks like the battery should fit in the box without too much issue. I'm also considering moving it under the bed in the front of the trailer.

Epoch sell a charger, any reason not to use it?:Epoch Charger

After I get an appropriate Li-ion charger, do I still keep the old converter and hook up the new Li-ion charger to it to run the 12v system when on shore power or can I get rid of the converter once the Li-ion charger is hooked up?

The last item is the charge monitor. If I get the Epoch battery with bluetooth does that cover me?

[vanderwielen]

https://www.youtube.com/watch?v=k-aaT-WCsus&t=7s

[DCPAS]

Originally Posted by smithcreek

I did a quick and dirty energy audit, 300Ah should be more than enough for what I need, and I like the look of the Epoch battery. I can weld if I need to, but it looks like the battery should fit in the box without too much issue. I'm also considering moving it under the bed in the front of the trailer.

Epoch sell a charger, any reason not to use it?:Epoch Charger

After I get an appropriate Li-ion charger, do I still keep the old converter and hook up the new Li-ion charger to it to run the 12v system when on shore power or can I get rid of the converter once the Li-ion charger is hooked up?

The last item is the charge monitor. If I get the Epoch battery with bluetooth does that cover me?

No particular need for the charger. Just change your converter to a Lithium model. I agree on not selecting a WFCO autoselect. There is no need to retain the ability to charge lead acid batteries. Changing the converter was easy.

We put in two 100amp hour LiTime batteries with bluetooth. No need to have a separate monitor. A really nice feature of bluetooth is that you can shut the battery discharge off which makes working on the electrical system easier and safer.

The Victron stuff is very cool and well made, but I did not see an advantage to buying Victron for the simple system we have. Now if I were going bigger and adding rooftop solar, that would be different.

[Mollysdad]

IF you choose batteries that fit in the existing battery box, you can save a lot of new wiring. However, then you need to deal with the batteries being in the cold, depending on where you're based. You can buy batteries that have heating circuits built in.
As far as days off the grid, I've gone four days with only my lead acid and a 100w. solar suitcase. I was very frugal and the weather was great. If you have additional campers (read-women) then the need for power goes up accordingly.
The converter is the battery charger. You have the old style single stage charger, as do I. There are multi-stage chargers suitable for lithiums that will be a direct drop in replacement. I'd look into those.
There's a wealth of information here, they'll be along shortly.
I'm just starting with ground based panels and some Victron parts.
It's a rabbit hole, you can spend $20,000 and never recoup that if you sell. I'm trying to stay on the cheap, er, frugal side.

[crispyboy]

I just went through this exercise but with an older trailer. The catalyst for my decision was last fall when the Boondocker converter went bad which in turn took out the lead acid batteries at the end of camping season. Black Friday sales came and I purchased 2 lithium batteries. I upgraded to a Progressive Dynamics lithium capable convertor. I opted for a DC/DC charger to protect the electronics in the truck and properly charge the batteries while going down the highway. I already had the Perko battery isolation switch in the trailer. I also installed a Victron shunt to monitor the batteries. The lithiums are a different animal from a lead acid battery so I am still a bit nervous about the safety of them. Li Times are made of cheap "Chinesium" materials but have a decent warranty. My lead acid batteries made it 5 years. Battle Born lithium were just too expensive.
My camping is currently a weekend warrior with some a longer week long trip thrown in since I am still working. Not interested in solar at this point in life.

1.) 2 - 100 AH lithium self heating batteries. https://www.litime.com/
2.) Victron bluetooth shunt. Batteries did not have built in monitor. https://www.victronenergy.com/batter...-battery-shunt
3.) Perko battery isolation switch -https://www.perko.com/catalog/catego...tery_switches/
4.) Victron DC/DC charger - https://www.victronenergy.com/dc-dc-...orion-tr-smart
5.) Progressive Dynamics convertor - https://www.progressivedyn.com/power-converters-2/

[JeffKim]

Originally Posted by smithcreek

Epoch sell a charger, any reason not to use it?:Epoch Charger

After I get an appropriate Li-ion charger, do I still keep the old converter and hook up the new Li-ion charger to it to run the 12v system when on shore power or can I get rid of the converter once the Li-ion charger is hooked up?

The last item is the charge monitor. If I get the Epoch battery with bluetooth does that cover me?

I don't know how they did things in 2013, but in more recent campers there is a converter box where the DC fuses and AC breakers are located. Located inside is the charger as a separate unit. It should have a AC source either wired to the AC side or a plug. The DC output is wired to the DC board. Again, yours might not be like this. But it should be a matter of replacing the wired in charger.

That said, the Epoch charger should work, but it appears the output is meant to plug into the battery. You would have to likely cut this off and strip the wire. But I'd opt for a charger that is meant for the converter box and RV duty. It will be powering all the DC circuits while plugged in and not just charging the battery.

Yes, the built-in Epoch battery monitor should be good enough. I wouldn't worry about heaters unless you plan on camping below 32F for long periods of time. In Minnesota we 3 season camp and I don't have heaters.

[gypsydad]

I went thru this last summer, after endless hours on the Forum...not that hard if your not wanting to "learn" all the best options to just replace a couple of your batteries with Lithium. Yes the Epoch 300AH 12V seems like a great choice, but a bit expensive. I surely would consider. I had not seen this option when I got my LiTime 100AH 12V Group 24 batteries last summer. (check pricing at LiTime- Mine were around $245/each; I did aso get a portable charger from LiTime as back up, but have not used since first time charging on my bench) The LiTime batteries are working great, they are a lot lighter than standard 12V LeadAcid, and come with built in Bluetooth monitoring so you don't really need to also consider a BMS or Shunt if you don't want to use additional hardware. Your converter should be swapped out for one that supports Li. Bestconverters.com is one source to check with online, but there are others also. If your using a portable solar set, thats pretty straight forward for charging. You can even get quick disconnect type set up to your batteries directly, if you don't have a solar plug on your 19'? As for real time use model with these, I went 6 days boondocking in Teton last fall, without power and still had 57% capacity; my old Lead Acid batteries I could go mayb 2-3 days without having to fire up the generator! Good luck.

PS- be careful...although there is a lot of great suggestions here on the Forum, you can also get caught up in the frinzy and buy a lot of stuff you may not really need...which may not bring back any $$ if you decide to sell..

[Glen Carter]

These days there are many methods to use. You have to decide how comprehensive your conversion will be and what products you choose to use. You have the option from very basic to overkill.

I converted my 2018 a number of years ago. I removed the WFCO converter and disconnected the TV charging (lithium battery is a different charged voltage than TV conventional/AGM). I installed a Victron monitor, Victron MPPT and Victron IP65 charger. Soon I'll be adding a electric refrigerator, Victron Orion XS DC-DC charging and a Epoch 460.

[Riverfield]

Hello.Currently have the original 1000 watt inverter, 2 non Battleborn 100 ah lithium batteries with Bluetooth, Cold temp and overheat protection. The batteries have done a great job but would love to switch over to 300 ah. We see that the battery fits easily into the battery box on our 23fbt…
Question is….can you SIMPLY install a 300 ah Epoch in place of the current 2 100 ah lithium batteries? Does the changeover mean updating the inverter or current wiring or is it an easy swap out? We are looking to keep things as simple as possible. Thanks!

[kb0zke]

FWIW, I'm leaning towards a pair of Epoch 300AH batteries, installed under the forward-facing dinette seat, with the Victron MultiPlus II mounted under the other dinette seat. That keeps all of the wiring runs fairly short and moves weight closer to over the axles.


The other idea is to install the MP II and four Redodo 280AH batteries under the front couch. A little more weight, farther forward, and longer wires, but nearly double the battery capacity for less money. Of course, prices will change before I actually purchase anything.

[smithcreek]

Wow, thanks for all the replies! I see some of you have/had very similar goals to mine. I just don't want to be on a three day camping/travel trip worrying about trying to find the spot of sunlight in the densely forested northeast state park campground, then follow it around all day or else run out of juice for the propane fridge!

I ordered the Epoch 300Ah battery with heater and bluetooth, the Epoch 50amp charger and the Epoch battery tray in case I end up moving it under the bed in front.

[richard5933]

If your goal is to make it through the weekend without worries of running out of battery power, the first thing you need to do is an energy-use audit. You need to know precisely how much power you anticipate using during these weekends.

Once you know your power needs, then you can figure how you're going to supply it. The simplest way is to leave home with a fully charged battery bank capable of going the whole weekend. Not practical for most of us, but easier with the more compact way lithium batteries store power. Still, you likely don't have room or money for that many lithium batteries.

A smaller battery bank is okay if you have a reliable way to keep it charged. Solar is the typical way of doing this if you're not plugged in. Whether your portable panels can keep up depends on their actual average output. Do the math and see if they produce enough to recharge what you're using over the weekend. Whatever they cannot produce you'll need to bring with you in the battery bank. Or get a larger portable solar array. Or put a few hundred watts of solar on the roof.

We have two 100A Battle Born lithium batteries and 400w of solar on the roof. We can go pretty much indefinitely in warmer months using the solar to keep our batteries topped off. I find this balance perfect for us. In the edge seasons (early spring and late fall)where heating is needed and solar is not as reliable things can get dicey and we've had to augment at times by charging from our TV or generator.

At the minimum, besides the lithium batteries you'll need an appropriate charger/converter. That's really about it for hardware. A battery monitor is usually added since the factory one in your Airstream won't really tell you much with the lithium batteries.

[RMNummi]

I’ve got a WFCO 8930/50 on a 2020 GT 25FBT. Switched the AGMs to a single Epoch 300ah. Does anyone have the part number to swap out the OEM charger? I’ve done the swap twice on older 23s. Fairly easy with the right part number….

[uncle_bob]

Hi

Lithium batteries operate at slightly different voltages than lead acid. I you try to run them on a lead acid charger, you will ruin them. You can not keep your 2013 era converter charger.

The stock converter chargers (if that's what you still have) are not the greatest thing out there. They seem to fail a lot more than they should. If yours has made it 10 years, you are pretty lucky.

There are a lot of heavy wires that run to the inverter and another set that run to the converter / charger. Move things around as part of this process and they become an issue. They are not easy to get to (unless you like dropping the belly pan ...).

These days a combination inverter / charger *is* an option. Can eliminate a lot of that wiring headache. The same big wires that feed the inverter also do the charging.

There are a number of settings you need to play with on *any* proper converter that goes onto lithium batteries. The "one size fits all" approach hasn't quite made it yet. That also is a reason for getting a unit that *does* let you do that rather than something that does not. Battery that live a good long time are what you are after.

If you had the stock AGM setup, it was two 100AH lead acid batteries. With lead acid, you get to use half that capacity. If they are the ones that came with the trailer (and are 10 years old), it's good guess you have been running at about 80% of that "brand new capacity" ( so 80AH).

One generic LiFePO4 battery will likely have a 100AH rating on it. If it's a good brand, you will get that entire capacity as useful output. To get the same capacity you have been running with, you would need *one* 100AH lithium battery.

That's about all you *must* have.

Bob

[Airlock]

Smithcreek, just a quick comment: I think the battery chemistry you are going to want to install to replace your AGMs is LiFePo (Lithium Iron Phosphate) and not Li-ion.

Gary