Battery Trials and Tribulations

Mellow_Yellow

Hello again! Still going strong with my 2014 T@B 320 S, one of the first units built with the Alde and integrated shower/toilet. 

I have been through numerous attempts to improve the battery situation, especially since most of my camping is off-grid on Vancouver Island with limited solar for 1/2 the year. 

1. I started with a nearly dead wet cell battery inherit from the previous owner. Disaster! First camping trip and all the alarms going off.
2. I tried a lithium battery but I had endless problems with it decharging, possibly due to not being compatible with my non-lithium converter. 

3. I switched to a 12V AGM battery which was great but it was not charging while under tow. I later found out that the 7-pin plug only had 4-pin wiring. I kept returning to the shop that installed the hitch and they finally figured it out and that got fixed. I use a simple ANCEL Bluetooth battery monitor so I was able to prove the “no charging under tow” problem. 

3A. The suitcase solar panel works great but it is of limited use off season under the dense forests at this latitude. 

4. I got the conversion kit for 2 x 12V batteries but it didn’t fit on the existing battery tray of my older BAL trailer and would have required welding. So I abandoned that idea. 

5. Now, I want more amp hours for my winter off-grid trips. I was limited to about 60ah with the single 12V AGM. I put a disconnect switch on the radio to further limit passive drain and the dreaded blue light. The Camco dual battery box just fits in front of the tub and I’m going to try that solution with 2 x 6V AGM battieries. https://www.amazon.ca/gp/aw/d/B07V4482W1?psc=1&ref=ppx_pop_mob_b_asin_title
 I’m hoping to have more ah to work with using this configuration. 

6. Also to mention, when my trailer is not in use, I shut down the breakers, pull a fuse and keep the battery on a simple trickle charger. Awkward but works great. 

By far, the most $ I have spent on mods and repairs has been in the battery department. Cleaning out the Mason bees that plugged up my fridge exhaust ran a close second. I’m hoping the dual 6V AGMs will do the trick. Still loving my little T@B!

Marceline

If you still have the lithium battery, I think you should give it another try. Yes, the converter will not fully charge it, but there are options for addressing this. 

You could:

1) Replace the converter with a newer converter with a lithium switch

2) Instead of charging the battery from the converter, get an external charger like a NoCo genius (not sure what trickle charger you're using now - maybe it has a lithium setting?)

By any chance are you running your 3way fridge on DC power when you're on the road? That's an enormous power drain that will be hard to overcome with any battery setup - especially if you're driving more than an hour or two.

I just don't think that it makes sense to buy AGMs, especially if you still have that lithium battery

Cherokee

Two 6v golf cart batteries are far better then 12v car batteries. Car batteries are made to provide starting power while golf cart batteries are made to run for the long hall. I replaced these with Glass Mesh a year ago. A 4x4 block below the forward one allowed my to slide these into T@B's box - the tight squeeze helps hold them in place.

Cherokee

Marceline said:

If you still have the lithium battery, I think you should give it another try. Yes, the converter will not fully charge it, but there are options for addressing this. 

You could:

1) Replace the converter with a newer converter with a lithium switch

2) Instead of charging the battery from the converter, get an external charger like a NoCo genius (not sure what trickle charger you're using now - maybe it has a lithium setting?)

By any chance are you running your 3way fridge on DC power when you're on the road? That's an enormous power drain that will be hard to overcome with any battery setup - especially if you're driving more than an hour or two.

I just don't think that it makes sense to buy AGMs, especially if you still have that lithium battery

Our 3-way runs on battery power connected to our TV with an alternator. We've pulled out T@B across this country and down 4x4 trails for years averaging about 300 miles a day on the road. When we stop for lunch we convert it to run on gas - an option one doesn't have with an electric only ref. However, YES use a trickle charger when the T@B is in storage and prolong the lead acid cells life. Changing to two 6V batteries is MUCH cheaper then a lithium conversion. We Boondock with the 3-way on gas for days at a time with 95w of portable solar utilizing the California sun and watch DVD's at night!   

 

Marceline

Cherokee said:

Our 3-way runs on battery power connected to our TV with an alternator. We've pulled out T@B across this country and down 4x4 trails for years averaging about 300 miles a day on the road. When we stop for lunch we convert it to run on gas - an option one doesn't have with an electric only ref. However, YES use a trickle charger when the T@B is in storage and prolong the lead acid cells life. Changing to two 6V batteries is MUCH cheaper then a lithium conversion. We Boondock with the 3-way on gas for days at a time with 95w of portable solar utilizing the California sun and watch DVD's at night!   

  

1. The 3way fridge constantly draws 10a+ when running on DC. Maybe your vehicle can supply that power, but many (most?) cannot without taking additional steps (DC-DC charger, larger gauge line wired to vehicle, etc). We've seen plenty of cases where people haven't realized this and run down their batteries in transit. If they're on their way to a campsite with hookups, it's no big deal. But if they're on their way to a boondocking site, it's  a big problem. 

2. @Mellow_Yellow mentioned that they already tried a lithium battery. If they still have it, it costs them nothing to try it again. Nothing is obviously MUCH cheaper than buying two new 6v batteries.

3. @Mellow_Yellow also mentioned that they can't generate much solar power where they camp ("Vancouver Island with limited solar for 1/2 the year"). So your crowing about solar power isn't very helpful or relevant. The picture you posted is just about 180degrees the opposite of their camping conditions. 

It sounds to me like @Mellow_Yellow needs to leave home with a full battery and an icy cold fridge, and ensure that their battery isn't depleted in transit so they arrive at their campsite with a 100% charged battery. Otherwise, they'll probably have to resort to a generator.

Cherokee

Marceline said:

Cherokee said:

Marceline said:

Cherokee said:

Our 3-way runs on battery power connected to our TV with an alternator. We've pulled out T@B across this country and down 4x4 trails for years averaging about 300 miles a day on the road. When we stop for lunch we convert it to run on gas - an option one doesn't have with an electric only ref. However, YES use a trickle charger when the T@B is in storage and prolong the lead acid cells life. Changing to two 6V batteries is MUCH cheaper then a lithium conversion. We Boondock with the 3-way on gas for days at a time with 95w of portable solar utilizing the California sun and watch DVD's at night!   

  

1. The 3way fridge constantly draws 10a+ when running on DC. Maybe your vehicle can supply that power, but many (most?) cannot without taking additional steps (DC-DC charger, larger gauge line wired to vehicle, etc). We've seen plenty of cases where people haven't realized this and run down their batteries in transit. If they're on their way to a campsite with hookups, it's no big deal. But if they're on their way to a boondocking site, it's  a big problem.

I've seen a lot these older T@B's all over the country with 3 ways HAVING NO PROBLEM with powering their 3 way with all kinds of TV"S - get out and look. I've pulled my T@B with two different TV's and had NO problems. BTW, Boondocking with a NEW refrigerator requires 4 times as much solar according to those who do it. The battery powered compressor requires a lot of electricity.

I've personally towed my T@B will few have and Boondocked  in rainy Washing State or Stormy Texas as well as sunny Arizona, Nevada and California  

2. @Mellow_Yellow mentioned that they already tried a lithium battery. If they still have it, it costs them nothing to try it again. Nothing is obviously MUCH cheaper than buying two new 6v batteries.

He states: "I tried a lithium battery but I had endless problems with it decharging, possibly due to not being compatible with my non-lithium converter." you replied replied correctly that he needed additional items. He has a choice get those items or go with two 6V AGM's- he will also need a new gauge to measure the power as the one in his T@B measures the drop in voltage to asses state of charge - which doesn't work with lithium battery.

3. @Mellow_Yellow also mentioned that they can't generate much solar power where they camp ("Vancouver Island with limited solar for 1/2 the year"). So your crowing about solar power isn't very helpful or relevant. The picture you posted is just about 180degrees the opposite of their camping conditions.

 I stated that this is a result of CALIFORNIA SUN and indeed, he may need a generator, but fortunately, he has a 3-way that runs on propane - so he won't have to run it as much 

 

It sounds to me like @Mellow_Yellow needs to leave home with a full battery and an icy cold fridge, and ensure that their battery isn't depleted in transit so they arrive at their campsite with a 100% charged battery. Otherwise, they'll probably have to resort to a generator.

Probably true

Cherokee

BTW, when you get your battery issues solved this post should help you should you ever get in a strong cross wind: https://tab-rv.vanillacommunity.com/discussion/18932/fix-for-refrigerator-vent-blues#latest

Marceline

Cherokee said:

I've seen a lot these older T@B's all over the country with 3 ways HAVING NO PROBLEM with powering their 3 way with all kinds of TV"S - get out and look. I've pulled my T@B with two different TV's and had NO problems. BTW, Boondocking with a NEW refrigerator requires 4 times as much solar according to those who do it. The battery powered compressor requires a lot of electricity.

It's great that it works for you, but this is a well-known issue with the 3way fridge running on DC. It's basic math. The 3way fridge draws 10a+ on DC and if you have a charge line from your vehicle that puts out just 2.5a, you're operating at a 7.5a deficit. If you have an 80aH lead acid battery and you drive for 5 hours, you've used up about half of the battery capacity before you even arrive at your destination. I think that you're mistaken if you think that most tow vehicles are going to output 10a+ without some modifications. That might be true of some trucks, but I doubt most SUVs supply that kind of power through the 7pin connector. Your situation is helped by the solar on the roof, but the OP doesn't have that. The older T@Bs mostly didn't have solar panels on the roof.

This issue comes up all the time in the T@B FB groups, and here are two examples in this forum I found with just one quick search.

https://tab-rv.vanillacommunity.com/discussion/comment/34031#Comment_34031
https://tab-rv.vanillacommunity.com/discussion/comment/208135#Comment_208135

The two types of fridges each have their own upsides and downsides, and since I have a 2way fridge (the clamshells have only ever had 2way fridges), I can provide you some information on that (I've been using it since 2016). The 2way fridge draws about 3.5a intermittently (when the compressor is running), which is of course less than the 10a constant draw of a 3way fridge on DC mode. The downside is that there is no propane option when I arrive at a campsite, so if I want to use the fridge, I have to be sure that I'm storing/generating enough power when off the grid. That can definitely be a challenge during the winter when days are shorter and under heavy tree cover (redwoods). This is why I was one of the first T@Bbers (that I know of) to install a lithium battery (2019). I'm mostly able to get by but there are times when it would be nice to have propane. As the price of lithium batteries drops, I'm tempted to replace the one I have (90aH) with one that's bigger.

Mellow_Yellow

Marceline said:I

If you still have the lithium battery, I think you should give it another try. Yes, the converter will not fully charge it, but there are options for addressing this. 

You could:

1) Replace the converter with a newer converter with a lithium switch

2) Instead of charging the battery from the converter, get an external charger like a NoCo genius (not sure what trickle charger you're using now - maybe it has a lithium setting?)

By any chance are you running your 3way fridge on DC power when you're on the road? That's an enormous power drain that will be hard to overcome with any battery setup - especially if you're driving more than an hour or two.

I just don't think that it makes sense to buy AGMs, especially if you still have that lithium battery

Hi Marceline - I no longer have the lithium battery. I mistakenly blamed the lithium battery for “not working” when the root cause was actually the 7-pin connector only being wired as a 4-pin connector. I kept showing up at the campsite with a decharged battery. 

My fridge is always off when under tow and I only run the fridge on electrical if I am plugged in to shore power. 

elbolillo

@Mellow_Yellow

You keep talking about your off-grid camping and the lack of solar generation. If this is the case, then LiFePo4 batteries are ideal for this type of situation. They would provide the most amount of usable amp hours.

As long as you are fully charged before heading out, a lithium battery would serve you well.

Mellow_Yellow

Marceline said:

3. @Mellow_Yellow also mentioned that they can't generate much solar power where they camp ("Vancouver Island with limited solar for 1/2 the year"). So your crowing about solar power isn't very helpful or relevant. The picture you posted is just about 180degrees the opposite of their camping conditions. 

It sounds to me like @Mellow_Yellow needs to leave home with a full battery and an icy cold fridge, and ensure that their battery isn't depleted in transit so they arrive at their campsite with a 100% charged battery. Otherwise, they'll probably have to resort to a generator.

So true! This is exactly how I camp: I leave home with a cold fridge and a full battery. Campsites here look more like this - dense shade, year round except when the sun is directly overhead or finds an opening in the canopy. I’m avoiding a generator at all costs - too noisy and smelly! 

pthomas745

Lithium batteries have changed dramatically in just a few years, and now it is even easier to increase amp hour capacity using the same size "Group 24" battery size that used to be "stock" sized lead acid batteries.  If you can fit two 6V batteries in the tub, then two Group 24 lithium batteries would fit, also.  They also could be stacked, or laid in several different configurations except up side down.  Not to mention being much much lighter.  In the end, two LiTime 100 amp hour batteries wired properly could bring you 200 amp hours of battery power.

https://www.amazon.com/Litime-LiFePO4-Battery-Upgraded-Lifespan/dp/B0CYQ371X4?th=1

Cherokee

Mellow_Yellow said:

Marceline said:

3. @Mellow_Yellow also mentioned that they can't generate much solar power where they camp ("Vancouver Island with limited solar for 1/2 the year"). So your crowing about solar power isn't very helpful or relevant. The picture you posted is just about 180degrees the opposite of their camping conditions. 

It sounds to me like @Mellow_Yellow needs to leave home with a full battery and an icy cold fridge, and ensure that their battery isn't depleted in transit so they arrive at their campsite with a 100% charged battery. Otherwise, they'll probably have to resort to a generator.

So true! This is exactly how I camp: I leave home with a cold fridge and a full battery. Campsites here look more like this - dense shade, year round except when the sun is directly overhead or finds an opening in the canopy. I’m avoiding a generator at all costs - too noisy and smelly! 

A nice shot of the mountains - Excuse me - but indeed, 180 degrees will place my T@B in a rain forest that we spent two nights and three days in. The Best solution would be two 12V Lithium batteries wired in parallel connected to a Lithium rated converter under the seat a seat in your T@B.

However, with my 3-way on gas and limiting  DVD viewing to 1 a night,  We only had a little sun while we visited an adjacent National Park, Our two 6V AGM batteries provided for us - though they were depleted at the conclusion of the third day when we left 

CatDaddy

Cherokee said:

The Best solution would be two 12V Lithium batteries wired in parallel connected to a Lithium rated converter under the seat a seat in your T@B.

Wiring two lithium batteries in parallel without taking precautions to properly match and/or balance them, is not a great idea. I'm an electrical engineer.  I would not do that on my rig. This is the source of some of the fires associated with lithium batteries.

Using two 6V batteries in series, if you can find them, is a much safer approach. Alternately, a power converter with two 12V inputs would be better.

I know this is a popular thing to do, I just don't advise it. If you really want to put two lithium batteries in series, the best practice is to measure their internal impedance and match them to within 1%.  That would mean either buying a matched pair or buying a bunch of them, testing them and returning the rest.

Putting two different type of batteries of different age and construction in parallel is a really, really bad idea.

elbolillo

CatDaddy said:

Cherokee said:

The Best solution would be two 12V Lithium batteries wired in parallel connected to a Lithium rated converter under the seat a seat in your T@B.

Wiring two lithium batteries in parallel without taking precautions to properly match and/or balance them, is not a great idea. I'm an electrical engineer.  I would not do that on my rig. This is the source of some of the fires associated with lithium batteries.

Using two 6V batteries in series, if you can find them, is a much safer approach. Alternately, a power converter with two 12V inputs would be better.

I know this is a popular thing to do, I just don't advise it. If you really want to put two lithium batteries in series, the best practice is to measure their internal impedance and match them to within 1%.  That would mean either buying a matched pair or buying a bunch of them, testing them and returning the rest.

Putting two different type of batteries of different age and construction in parallel is a really, really bad idea.

Wiring two or more LiFePo4 batteries in parallel is a very common practice and done correctly is certainly safe. The Lithium options from NuCamp on both the Tab 400 and Tab 320, wire 4 and 2 batteries in parallel respectively.

Regarding fires, you may be confusing Lithium Ion batteries with LiFePo4 batteries.

CatDaddy

elbolillo said:

Wiring two or more LiFePo4 batteries in parallel is a very common practice and done correctly is certainly safe. The Lithium options from NuCamp on both the Tab 400 and Tab 320, wire 4 and 2 batteries in parallel respectively.

Regarding fires, you may be confusing Lithium Ion batteries with LiFePo4 batteries.

I'm an electrical engineer. I know what I'm talking about.  I am not confused.  Wiring two properly matched and balanced LiFePo4 batteries in parallel is common. Wiring two random LiFePo4 batteries in parallel is dangerous. I wouldn't do it.

I agree that lithium ion batteries are less forgiving than LiFePo4 batteries.

elbolillo

CatDaddy said:

elbolillo said:

Wiring two or more LiFePo4 batteries in parallel is a very common practice and done correctly is certainly safe. The Lithium options from NuCamp on both the Tab 400 and Tab 320, wire 4 and 2 batteries in parallel respectively.

Regarding fires, you may be confusing Lithium Ion batteries with LiFePo4 batteries.

I'm an electrical engineer. I know what I'm talking about.  I am not confused.  Wiring two properly matched and balanced LiFePo4 batteries in parallel is common. Wiring two random LiFePo4 batteries in parallel is dangerous. I wouldn't do it.

I agree that lithium ion batteries are less forgiving than LiFePo4 batteries.

I don't recall anyone on this thread discussing wiring two random LiFePo4 batteries in parallel.

Properly installing two LiFePo4 batteries in parallel is safe. Your comment makes it seem like 6v batteries wired in series are much better.

Cherokee

elbolillo said:

CatDaddy said:

Cherokee said:

The Best solution would be two 12V Lithium batteries wired in parallel connected to a Lithium rated converter under the seat a seat in your T@B.

Wiring two lithium batteries in parallel without taking precautions to properly match and/or balance them, is not a great idea. I'm an electrical engineer.  I would not do that on my rig. This is the source of some of the fires associated with lithium batteries.

Using two 6V batteries in series, if you can find them, is a much safer approach. Alternately, a power converter with two 12V inputs would be better.

I know this is a popular thing to do, I just don't advise it. If you really want to put two lithium batteries in series, the best practice is to measure their internal impedance and match them to within 1%.  That would mean either buying a matched pair or buying a bunch of them, testing them and returning the rest.

Putting two different type of batteries of different age and construction in parallel is a really, really bad idea.

Wiring two or more LiFePo4 batteries in parallel is a very common practice and done correctly is certainly safe. The Lithium options from NuCamp on both the Tab 400 and Tab 320, wire 4 and 2 batteries in parallel respectively.

Regarding fires, you may be confusing Lithium Ion batteries with LiFePo4 batteries.

Thanks for the electrification. ROA off road sellsTrailers made in Australia are often wired that way and I know some good T@B dealers that offer multiple  Lithium battery conversions. I guess like most things - a professional installation is best     

elbolillo

Cherokee said:

elbolillo said:

CatDaddy said:

Cherokee said:

The Best solution would be two 12V Lithium batteries wired in parallel connected to a Lithium rated converter under the seat a seat in your T@B.

Wiring two lithium batteries in parallel without taking precautions to properly match and/or balance them, is not a great idea. I'm an electrical engineer.  I would not do that on my rig. This is the source of some of the fires associated with lithium batteries.

Using two 6V batteries in series, if you can find them, is a much safer approach. Alternately, a power converter with two 12V inputs would be better.

I know this is a popular thing to do, I just don't advise it. If you really want to put two lithium batteries in series, the best practice is to measure their internal impedance and match them to within 1%.  That would mean either buying a matched pair or buying a bunch of them, testing them and returning the rest.

Putting two different type of batteries of different age and construction in parallel is a really, really bad idea.

Wiring two or more LiFePo4 batteries in parallel is a very common practice and done correctly is certainly safe. The Lithium options from NuCamp on both the Tab 400 and Tab 320, wire 4 and 2 batteries in parallel respectively.

Regarding fires, you may be confusing Lithium Ion batteries with LiFePo4 batteries.

Thanks for the electrification. ROA off road sellsTrailers made in Australia are often wired that way and I know some good T@B dealers that offer multiple  Lithium battery conversions. I guess like most things - a professional installation is best     

I did my own installation with Battleborn batteries. I consulted with Battleborn regarding the specifics of the installation and have 4 - 100ah batteries wired in parallel. This setup has worked flawlessly for me.

SLJ

My experience:
I changed my '21 320S to two inside 100AH Lithiums. We pretty much only boondock. Only plugged in once this year (ADK Rally). After two years with the 105 watt panel on the roof and a portable 200 watt suitcase, the lowest my batteries have ever been powering the fridge 24/7, lights, pump, stereo, TV, etc. the last two years is once down to 45% and that was with over a week of rain and total overcast. I figure I have at least five days of power with absolutely no recharging. The Ford truck typically provides 7.5 amps when towing and 5.5 when idling so more than enough to run the 12 volt fridge and charge the batteries.

elbolillo

We just did 11 days / 10 nights with limited solar charging. We pulled into home with 16% left of our 400ah setup left. We had a few days with extended inverter use to power our Starlink. So that definitely ran it down faster.

AnOldUR

Cherokee

CatDaddy said:

Cherokee said:

The Best solution would be two 12V Lithium batteries wired in parallel connected to a Lithium rated converter under the seat a seat in your T@B.

Wiring two lithium batteries in parallel without taking precautions to properly match and/or balance them, is not a great idea. I'm an electrical engineer.  I would not do that on my rig. This is the source of some of the fires associated with lithium batteries.

Using two 6V batteries in series, if you can find them, is a much safer approach. Alternately, a power converter with two 12V inputs would be better.

I know this is a popular thing to do, I just don't advise it. If you really want to put two lithium batteries in series, the best practice is to measure their internal impedance and match them to within 1%.  That would mean either buying a matched pair or buying a bunch of them, testing them and returning the rest.

Putting two different type of batteries of different age and construction in parallel is a really, really bad idea.

I agree - far less expensive  - keep them on a trickle charger when the trailer is idle and they will last - It just depends on how long he wants to Boondock without recharging 

CatDaddy

elbolillo said:

I don't recall anyone on this thread discussing wiring two random LiFePo4 batteries in parallel.

Properly installing two LiFePo4 batteries in parallel is safe. Your comment makes it seem like 6v batteries wired in series are much better.

By "random" I meant any two batteries that were not specifically matched.

Two 6V batteries in series are inherently safer because there is no chance of a weak cell being overcharged by stronger cells.

If you wire two LiFePo4 batteries in parallel, you are depending on the BMS (Battery Management System) to keep you safe. In my experience as a professional electrical engineer, that confidence is not well founded. There are plenty of BMSs out there that will not handle being paralleled with another BMS. 

As I have stated a few times now, I would not put two LiFePo4 batteries in parallel unless I was highly confident that the batteries were matched and the BMS could handle it. 

Battleborn batteries likely have a good BMS, but I would not assume that all BMSs are created equal.

CatDaddy

AnOldUR said:

This could be a problem with older lithium batteries without the advanced BMS's that most of today's have. My thought is that mismatching batteries with good BMS's will simply result in poor performance, but not be dangerous since each battery's BMS should prevent overcharging.

Older LiFePo4 batteries and current LiFePo4 batteries with poor BMS. There are LOTS of crappy BMS out there!

Sharon_is_SAM

@Mellow_Yellow - you may want to consider a 200+ amp lithium battery.  Not sure how long you stay out, but, if you are running the frig and Alde on LPG, you should be able to last at least a week without charging.  Do you know your typical daily usage?  

Cherokee

Marceline said:

Cherokee said:

I've seen a lot these older T@B's all over the country with 3 ways HAVING NO PROBLEM with powering their 3 way with all kinds of TV"S - get out and look. I've pulled my T@B with two different TV's and had NO problems. BTW, Boondocking with a NEW refrigerator requires 4 times as much solar according to those who do it. The battery powered compressor requires a lot of electricity.

It's great that it works for you, but this is a well-known issue with the 3way fridge running on DC. It's basic math. The 3way fridge draws 10a+ on DC and if you have a charge line from your vehicle that puts out just 2.5a, you're operating at a 7.5a deficit. If you have an 80aH lead acid battery and you drive for 5 hours, you've used up about half of the battery capacity before you even arrive at your destination. I think that you're mistaken if you think that most tow vehicles are going to output 10a+ without some modifications. That might be true of some trucks, but I doubt most SUVs supply that kind of power through the 7pin connector. Your situation is helped by the solar on the roof, but the OP doesn't have that. The older T@Bs mostly didn't have solar panels on the roof.

This issue comes up all the time in the T@B FB groups, and here are two examples in this forum I found with just one quick search.

https://tab-rv.vanillacommunity.com/discussion/comment/34031#Comment_34031
https://tab-rv.vanillacommunity.com/discussion/comment/208135#Comment_208135

The two types of fridges each have their own upsides and downsides, and since I have a 2way fridge (the clamshells have only ever had 2way fridges), I can provide you some information on that (I've been using it since 2016). The 2way fridge draws about 3.5a intermittently (when the compressor is running), which is of course less than the 10a constant draw of a 3way fridge on DC mode. The downside is that there is no propane option when I arrive at a campsite, so if I want to use the fridge, I have to be sure that I'm storing/generating enough power when off the grid. That can definitely be a challenge during the winter when days are shorter and under heavy tree cover (redwoods). This is why I was one of the first T@Bbers (that I know of) to install a lithium battery (2019). I'm mostly able to get by but there are times when it would be nice to have propane. As the price of lithium batteries drops, I'm tempted to replace the one I have (90aH) with one that's bigger.

1) I had the good since to have a T@B dealer wire my Jeep before I bought my T@B - I have NO idea who wired the Toyota Van in the first post or what gauge of wire was used

2) In the second post the M-5 BMW wiring wasn't stated or the output of the alt

3) I rented a Frontier and towed with it BEFORE I bought one - both were factory wired

4) We both agree that propane is good to have when off grid. However, Sparky WILL NOT light if the trailers not level or the wind is blowing hard - I've often spaced something over the pilot light vent secured with a buggy cord when we camp the wind

5) The 3 way vents it's condenser to the outside while the new 2-way apparently vents into the interior of the T@B - just like a Ref in the kitchen at home-not a problem for the air-8 on shore power, but not good for Boondocking in warm weather. 

6) We supplement our T@B's 3 way with an Otter Cooler from our over-land days with the jeep - this may work for you. We use it on long trips

In short, neither of us have a perfect solution      

Mellow_Yellow

@Sharon_is_SAM. I am pretty frugal especially during winter “dry” camping. I don’t have a way of measuring daily usage. 

Sharon_is_SAM

@Mellow_Yellow - we tow with a 2015 Sienna as well.  We will be replacing our AGM battery with lithium come spring.  We need more reliable battery life while boondocking as well. 

 To me, it sounds like you can use an easy fix.  Instead of changing converters, just install a 200 A battery in the tub and buy a lithium compatible battery charger to use at home to recharge after camping.  Follow the battery manufacturer recommendation regarding charging current.  Charging time depends on degree of battery depletion and the current of the charger.  The lower the current, the slower the charge.  You first need to measure the room in your tub to see what fits.

SLJ

I didn't change out the non-lithium converter in my '21. Instead I put in a Victron Smart charger and a cut off switch right at the lithium batteries. When plugged into shore power I just shut off the batteries and let the smart charger do the battery charging. It was cheaper than swapping out the converter to a newer one and the Victron smart charger charges the lithiums at a higher rate (20 amps). When I unplug I just turn the batteries on again.

AnOldUR