What battery is in my 2018 T@B 400?

Deb55

How can I tell if my 2018 T@B 400 has the single 12v AGM battery or the 2 6v AGM batteries? The camper was manufactured in March of 2018. I can't see what it is because it's inside of a black plastic box under the bed. I'm adding rooftop solar, and I want to put an additional battery in as well. Will I need to match the volts (6 vs 12) or will either do as long as it's AGM? Thanks! 

Denny16

You probably have the two 6-volt AGM batteries wired in series to get 12VDC total service inside the black battery box if your TaB400 was built after Feb. 2018.
You can lift up the passenger side of the bed, after removing the mattress, and you should have access to the battery box.   This was the first battery mod to the TaB400 which started out with a single 12VDC AGM battery in the same spot, but no box.

Cheers

Deb55

@Denny16 thanks!  I'm glad I asked - - I had assumed that I had the 12v battery, but I became suspicious that I really had the 6v mod., which I guess is a good thing! Now, do you know, or does anyone else know, can I mix in a 12v with these 2 6v batteries for extra amp hours when boondocking? I was thinking of adding a 100 amp hour 12v AGM in the space under the middle section of the bed. I did a bit of searching, and I think this is possible. I don't want to order the wrong thing! 

Denny16

Should not be an issue, as the solar and electrical,system see the two 6VDC batteries as a 12VDC battery.  I would check to see how many amps the 6VDC batteries are, if they are 200 amp, you may not need the extra battery.  We have a 12VDC 200 amp battery, with solar option, which handles the electrical system just fine.  Try camping with your current setup and see how it goes.  One thing you might add first is the Gictron shunt battery monitor setup, so you can see exactly what your power requirements are while camping, and go from there,
cheers

DenisP

@deb55 I have a 2018 400 made March 2018  with factory 200 watt solar and the 2-Six volt batteries (224 amp/hr). Our experience is that the battery capacity has been sufficient for our camping which is in mostly State and National Parks along with other dry camping.  (over 100 nights with less than 40% with electric hookups).  I do have a 100 watt solar suitcase which I have needed twice when in shady site for a few days and every month for a day to top off the batteries when in covered storage.  I added a Victron 712 Battery monitor which I have found invaluable monitoring for the battery usage and true State of Charge (SOC). 

Verna

@Deb55, I stayed in Arizona the winter of 2018/2019 For 5 months in dispersed camping with only water, no electricity.

The two 6 volt AGM batteries with 200 watts of solar took care of all of my needs. This included a Dish receiver and satellite (love to watch my basketball!), The 12V TV, recharging the DeWalt 20V lithium batteries used in my drill, fan and other tools (recharged through the in-house inverter), the electric spark from the battery needed to start the Alde for heat and hot water, and recharging my electronics (phones, iPad, computer, Kindle, etc.), and lighting. No problems were experienced. 

I truly do not believe you need twice this much battery storage. I have friends who are full timing in AZ still due to the COVID-19 restrictions in their home bases and they have pretty much the same setup with no problems. 

Deb55

@Denny16 @DenisP @Verna thanks for your insights. Very helpful!  I've revised my thinking on this project, and decided to have the factory install the 190 watt rooftop panel plus Victron controller, and additionally the Victron 712. I like the feature that tells you how many days of battery remain based on your usage. I'm setting things up with Austin at NuCamp now. Our planned summer vacation whitewater gathering in NC was canceled, so now we have the time to go to Ohio! 

Denny16

Good choice, that is how we have our late 2018 TaB400 electrical setup, factory installed solar, with Victron 75/15 MPPT controller and I added the 712 battery monitor.  Do have fun with your trip to Ohio.
cheers

DenisP

@Deb55 Enjoy your visit(pilgrimage) to SugarCreek. The factory tour and putting faces to the names is well worth it. 

DenisP

@Deb55 A couple of things you might consider while getting the work done at NuCamp.  The addition of a solar outlet (Zamp or SAE) might be helpful in the future, if you want to add a solar suitcase.  The 2021 400's have switched the positions of the Alde display and the Coolcat thermostat which would make reading the Coolcat display easier for you.  Not big things since they would have 400 and doing electrical work.  Not trying to spend your money. 

Tundra57

I have fitted two extra 6v batteries to my 2019 tab. It is not an easy task. They have to be in a sealed box and tied in to the intake and vents that are in the black box. I used a plastic box made for four gc2 frame batteries. You should buy batteries with the same specifications  as the two you have to make sure they share correctly. The floor under the current batteries is milled out as there is only just enough height for the batteries and box. But the floor is double there. When you make it larger you end up with no floor there and have to support it. I used aluminum plate.

I would definitely make sure you really can't do without them before attempting this like @Verna says.

You could go with lithium possibly get more capacity to fit in the current battery box space. Much more expensive, but way less work. Lithium is supposed to have a longer lifespan than AGM too.

Denny16

Interesting, Wondered how they got,the taller batteries to fit in the rear area.

The floor under the rear storage floor is the Azdel trailer floor, so it should be able to support the weight spread out over the battery area, after all, this is the floor under you thin floor covering you are walking on in the trailer.
cheers

Deb55

@Tundra57 we've decided to forego the extra battery, and install a Victron battery monitor instead, along with the solar panel and the Victron controller. We'll be making a trip from MA to OH to have it done at the factory. 

Tundra57

@Denny16 there is a big gap between the rear storage plywoid floor and top of a black layer which probably is the adzel floor. If you look at the bottom of the bed lift up support you can see a slot. Under there runs power, water and maybe alde. They are right under the current battery box. I think tgey created a false floor tmake it level for the pipes to run under, but when they moved the batteries there too, it was too high for them, so they created a dip just where the batteries fit. If you route out that dip further toward the back of the camperyou can then see the black adzel floor, but it is lower and there are some supports holding it up to keep the gap. So no you cant just machine out the whole thing as you would have to reroute the pipes too. I also am not good with the concentrated weight of 4 batteries in such a small area sitting on the adzel floor. So I prefer my solution. I have pictures if anyone is interested.

gspdx

Good choice @Deb55  You can always upgrade the batteries latter if needed, but if you are conservative in your use of electricity you will probably find you have enough, especially with the solar panel.  

N7SHG_Ham

I ordered my 2019 400 with factory solar and had the factory optionally add the BM 712. I have had no issues with power running out when boondocking (two way fridge) for two days/three nights. Battery was back to around 💯 each day.

I eventually want to upgrade to LiFePo4, replacing the stock 2x AGM with 2x lithium. That will give double usable capacity in same physical space.

While so far I haven't needed more AH, the other benifits of LiFePo4 are very attractive. One major benifit is faster charging and no I'll effects over time partially charging, both of those go hand in hand with boondocking and running a generator for short periods in case of cloudy weather.

Deb55

@N7SHG_Ham lithium batteries are SO expensive!  We're figuring the solar upgrade (plus the trip to Ohio to have it done) will be all that's in the budget for now. I bet those batteries are nice, though! 

Denny16

Thanks Chris, I know why the floor was raised.  And I agree, I do not think I want the extra weight of two more batteries in the back either.  

My current battery is a single large 12VDC 200AH battery that fits on top the raised floor.  Plumbing runs are on the edges, and the Alde pipes are all the way back, at least on the construction photos I have seen, this is where they are.  Towards the front of the bunk, the galley water pipes are under the front part of the false floor, I believe.  I think I would change to LiPro batteries, replacing the current battery, instead of adding more AGMs and the extra weight.

I am going to find out for sure, where the hidden wire runs and plumbing runs are, when I get my floor replaced with the Azdel floor.
cheers

N7SHG_Ham

@Deb55 the initial cost is high, no argument there. Some of the benifits will never be realized if you are on shore power all the time or most of the time. In those cases it likely isn't the upgrade you need.

Over time however a LiFePo4 battery is cheaper than any other chemistry (per AH of useable energy) if life projections of 10+ years turn out to be true. In addition there are a ton of benifits if you can get past the initial purchase price. More useable power, no Purkuert effect, lighter weight, no harm to battery from partial charges, no maintenance (AGM also has that advantage), faster charging time and maybe others I am forgetting. You really have to look at your needs and the long game other than just upfront pricing. Just like buying a NuCamp product, price is way higher per size than most any other RV, yet obviously folks lay out the cash everyday!

Denny16

Well put, I think in the long haul lithium is the way to go.  When my current battery fails, or I decide I need more battery amps. available, I will swap out to a Lithium battery.
cheers

Tundra57

@Denny16 if you do find out where the rubs go please share. I also noticed in the back wall there is a short divider keeping the bed mattress away from the back wall. There seems to be a large gap right down the back. If the alde hoses run back there, think its another source of heat? I never noticed it until doing this mod.  

Denny16

On the YaB 400, that gap behind the bunk, is above the Alde radiator unit in the back center section, and that is were you heat come up into the rear bed area.  Also, on the  2018/2019 models, the raised floor (notice the notch in the front panel under the bed) is the cold air return, creating a convection air flow.

Will get some photos (hopefully) to share when the TaB gets partially dismantled, showing the wire and plumbing runs
cheers

Tundra57

@Denny16 my bed topper squashed the gap shut. Ill have to put some spacers there to hold it open. Thanks for the information.

Denny16

The 2018 TaB 400 originally came with a single AGM 12VDC 225 amp. battery through Jan 2018, some time after that, nuCamp went to the two-6VDC AGM battery setup.  In either case, you do not want tp discharge them below 12VDC (40-percent).  You will shorten the battery life.

Good luck getting your battery recharged back up.  It can be done in most cases, just takes several days of charging.
cheers

Deb55

@DenisP we're back from Ohio, but since we had the work done on a Saturday, we couldn't get the tour. Still it was fun to see where our 400 was born! We stayed at Wolf Run State Park for a few days, and went ziplining! Could you tell me what you put in your battery monitor for the battery settings, since your camper is the same as ours (month and year of build). I've done some searching around on this forum, and I think I have it right but I'd like to double check if you don't mind. Thanks! 

Denny16

Deb, We used the default AGM setting, and added 200 amps for battery size.  

Seems to work well with this setting.  I would do a screen shot for you, but our TaB is in the shop having the floor replaced, and Boondock package added.
cheers

DenisP

@Deb55 this is a screen shot of my battery settings  

Denny16

Deb, This is about what we used, except the amp size for my single 12VDC is 200 amps, (the duo 6VDC may be more), and my charged voltage is set to 12.85, which is fully charged voltage with the Interstate 200 amp AGM, everything else is the same as shown by Dennis.

Cheers

DenisP

@Deb55 I have attached the spec sheet for our Harris 6v AGMs. 

Deb55

@DenisP @Denny16 thank you! Denis, I had the battery specs set exactly the same as your screen shot, except I had the charge set to 13.2 instead of 14.1. I'll change it to match yours, but I'm not knowledgeable enough to know what difference it makes! I really have no idea what these terms mean, but if I can at least geek out enough to know what my battery can handle while boondocking, I'm good! 

Deb55

@DenisP also, while I'm picking your brain, what did you use when choosing the battery setting on the solar controller? Ours was set to gel by default, and I read that it should be close enough. Is there another setting in the drop down list that's better?