Lithium or not

Kr@cken

Hoping for some advice about next steps. Going to upgrade my purchase battery to something that will allow for extended 5-7 days boondocking. The T@B facebook has been very helpful and is mixed between recommending lithium or 24V AGM. My dealer is encouraging a 2 X 6V battery “golf cart “ configuration. Any advice? I appreciate all your expertise!

pthomas745

Edited:  the original poster says they have solar, so my post here is redundant.  Nothing to see here, scroll down!

You don't know what you need until you know how you camp.  Spending a lot of money on any of these solutions is fine.......if you know what you want to power.  Spending a thousand for a lithium battery and then huddling up to your Luci light at night because you "don't want to use use much power" is a waste of the upgrade.  A solar panel would be a better option until you know how much power you want to use.  And, then upgrade your battery IF you need to.

Kr@cken

I have a 2020 T@B 320 that came solar but live in the Pacific Northwest so I can’t really rely on sunshine as an consistent source of power. Most of our spots are heavily forested and a day of sunshine outside of July/August is a gift.. I agree that would be the best option. 

VictoriaP

@dsfdogs Advice? I know you went with lithium.

@j@ydub You’re correct to be concerned about solar’s ability to keep up on the wet side of the mountains. My 100 watt Renogy panel can produce as little as 10 watts at noon in July if it’s cloudy, and the trees are of course another issue. I ended up buying a tiny 700 watt propane fueled generator to top off my group 27 AGM battery as needed for those days; it’s lightweight and a bit lower maintenance than the gas-fueled gensets, will run off the trailer’s tank or a 1 lb green Coleman propane canister. I’m definitely eyeing lithium as my ultimate solution, but for now, between conservative power usage, the portable solar, and running the generator for a few hours here and there, it’s pretty easy to keep up.

Sharon_is_SAM

Well, you can't run a 24v  battery - your appliances are all wired for 12 volt. 

Assuming that you can't recharge, 2 6v AGMs will give you only about 125 amps up to the 50% discharge where most feel the need to recharge.  Some folks feel comfortable discharging lower, just know that it will reduce the longevity of your batteries (we are talking 800 charge cycles vs 1000 charge cycles).  You will not get 5-7 days out of this running the frig if you can't recharge via solar or generator.

MarkAl

I'm in the process of adding two matched 100 watt panels in series that can be moved to the site's best light. These have their own Victron controller that will be networked to the trailer's 105* watt array/controller. As stated above in the wet side of the PNW worst case I'll be lucky to get enough light for 10 watts or less on each panel (20 watts total so in 5 hrs = 8Amp*Hr). Having them in series allows enough voltage to turn on the the controller and do some charging of the battery. With this little light the installed solar panel system will not turn ON so only the remote arrays will be any help. I believe this will (worst case) allow my batteries to only delay emptying their reserve but anything will help. Note that a battery monitor w/ current shunt is critical if you want to monitor actual reserve. I chose two 6 volt Lead-Acid for cost and compatibility with trailer and tow vehicle systems. Other than the added weight and shorter life they have slightly more reserve than the equivilent 100 A*H LiFe battery. 

*BTW the 2021's 320's Factory solar is now 105 watts not the previous years 130.

4ncar

I have dual 6v lead acid GC2s. 235ah capability. Depending on how frugal one can be...many days of battery power....

[Deleted User]

Lithium batteries' performance is based on them charged to more than 12 volts. When and how do you plan to accomplish that is the elephant in the room. They also have to be isolated from your 12 V system or they'll drain it. You need an expert to engineer it and when you're done they're not worth it and catch fire and don't charge at low temperatures and need a heat jacket... I plan several large AGMs and a sailboat wind generator (WEG) to supplement the solar panel and hope to rin the AC with the inverter for a little while. 

Denny16

Good luck running a TaB AC with an inverter (you need a 3,000 watt inverter) and using AGM batteries.  Non Lithium batteries do not have the available watt hour, unless you have a large bank of batteries.  To get 400 amps of power your re going to need 800. amps of batteries, and this might give you 4-6 hrs of AC run time!  A better option is to just get a good generator.  The Honda 2200i wil, run the Air8 or Cool. Cat.

RV systems designed to be used off grid, and provide power for AC units and heating systems, use Lithium battery banks, giving them 800 to 1200 amps of useable power.  You could not haul enough AGMs in a TaB to meet this requirement.  

A 200 amp AGM battery weighs in at 128 lbs, a deep cycle version 138lbs times four, puts 512 to 550 lbs of weight behind the axle.  The next issue is a 128lbs battery has a floor loading weight around 2lbs per square inch. 

If the frame will support this load, you would have to re-engineer the floor to handle the load.  Then you would loose 420-450 lbs of cargo capacity, water is going to add another 250 lbs to your overall weight. 

Where the battery large AGB battery/batteries are located in the TaB400, the floor is reinforced under the battery to take the 120-150lbs load.  The previous owner of our TaB400 relocated a 130lbs AGM battery to the center are under the bed, instead of its original location on the passenger side of the storage locker.  This threw the load balance in the trailer off, and the floor sagged a little under the load.  I had to move the battery back into its original location.

A trailer is like a boat, you need to be sure your cargo and systems balance each other, and maintain the correct tongue weight, and keep the weight under the GVW max load.

 cheers