Dual 6V Batteries.....

Jdcouple

Dual 6v AGM batteries.... will the 2017 T@B Outback charger work? Zamp system? Any negatives to going to a Dual 6V AGM setup? Any help is great.....

rfuss928

Why dual 6v instead of dual 12v?

wizard1880

I went dual golf cart batteries after researching my options.

The difference with a 12v x2 setup is that any 12v group 24 or 27 is not a true deep cycle battery.  The plates are thinner, so they can only take a fraction of the cycles.  Unless you use group 27s, they're lower in AH than golf cart batteries.

While it's possible you can buy a large enough 12v true deep cycle battery, they are not common and can weigh over 100 lbs, and they are expensive.  Golf cart batteries are basically an exact half of a 12v battery, so you have two halves that are easy to move and cost much less because they are so common.  Batteries plus sells them for $99 each or less, with a 10% off online pickup purchase.  No need to buy Trojans, either.  Their suble difference in quality doesnt justify their >30% cost difference.

The zamp works great, and the built in converter charges them OK.  You can increase your battery's life by using a smart charger such as a CTEK to top them off from time to time.

jkjenn

Jdcouple said:

Dual 6v AGM batteries.... will the 2017 T@B Outback charger work? Zamp system? Any negatives to going to a Dual 6V AGM setup? Any help is great.....

Check your inbox.

mash2

Can use 2 6 volt in series or 2 12 volts in parallel.  I have 2 12v in parallel and have had good luck with charging (hook up + on 1 battery and negative  on other battery)

ColoradoJon

Dual 6V (GC2) batteries will give you many more amps than dual 12V batteries (group 24).  225-240 amp hour range.  The on board converter will charge them but it is not very efficient at doing so and it will struggle to give them a full charge.  I recommend an external smart charger like the Norco, CTek, or Solar Pro-Logix chargers.

lapowers57

Dual 6 volt batteries can give you more AH but at the cost of a larger size and weight.  

rfuss928

lapowers57 said:

Dual 6 volt batteries can give you more AH but at the cost of a larger size and weight.  

Absolutely correct.   For any given battery type the volume and mass basically determines the watt-hours capacity.  Whether it is two 100 amp-hour 12 volt batteries or two 200 amp-hour 6 volt batteries the pairs will weigh just about the same and both will store 2400 watt-hours energy.

Generally:
-Two 12v batteries provide greater flexibility in the ability to be used and charged one at a time.
-High capacity 6v batteries are more common and less expensive versions are often available.

The cost for either set-up using AGM batteries mentioned in the OP will likely be essentially the same.

jkjenn

wizard1880 said:

I went dual golf cart batteries after researching my options.

The difference with a 12v x2 setup is that any 12v group 24 or 27 is not a true deep cycle battery.  The plates are thinner, so they can only take a fraction of the cycles.  Unless you use group 27s, they're lower in AH than golf cart batteries.

While it's possible you can buy a large enough 12v true deep cycle battery, they are not common and can weigh over 100 lbs, and they are expensive.  Golf cart batteries are basically an exact half of a 12v battery, so you have two halves that are easy to move and cost much less because they are so common.  Batteries plus sells them for $99 each or less, with a 10% off online pickup purchase.  No need to buy Trojans, either.  Their suble difference in quality doesnt justify their >30% cost difference.

From what I have read, day to day performance between Trojan and other batteries is not a huge difference, but other RV owners seem to indicate longevity on Trojans is better.

wizard1880 said:

The zamp works great, and the built in converter charges them OK.  You can increase your battery's life by using a smart charger such as a CTEK to top them off from time to time.

You aren't using the inside converter to charge if you use a solar panel, you are using the solar controller. I would recommend looking into an MPPT controller.

wizard1880

The zamp and it's own built in charge controller, and the T@Bs own built in WFCO converter are the two that I meant there.  Sorry for any confusion.

Nomad

Always find it amazing how many threads there are on batteries - Would think the definitive answer is somewhere :-)

wizard1880

That's the thing.  There's just a myriad of options and methods, and every person has different needs or expectations.  It's exponential

Nomad

And opinions :-)

AldebaranJill

Opinions based on actual data (like having a TriMetric meter, measuring specific gravity) I think might be called facts. 

Nomad

Hey, 2+2=3 for crying out loud. Get you facts straight :-)

JustJohn

JD, I went with a single AGM 12v battery. It has a 155 ah rating and weighs 95lbs. It also fit the tub of my Outback without the need for any modification. The standard charging system handles it with no issues and I have camped for 11 days straight using a 100w suitcase panel without a problem. 

Ratkity

JustJohn said:

JD, I went with a single AGM 12v battery. It has a 155 ah rating and weighs 95lbs. It also fit the tub of my Outback without the need for any modification. The standard charging system handles it with no issues and I have camped for 11 days straight using a 100w suitcase panel without a problem. 

Oiy!! Now that's a workout. Lifting 95 lbs up and over the Outback Tub lip!!!

Sharon_is_SAM

Thanks for that info JustJohn.  That is the setup that we plan to use.  I thought I may need to add another 50 - 60 watt panel, but your 11 day results are encouraging!  What charge controller are you using?

T@Balong

Just John..........which AGM 12v battery did you go with?   And you are saying it fits in the same case as the batteries that normally come with a T@B?

Airliner

lapowers57 said:

Dual 6 volt batteries can give you more AH but at the cost of a larger size and weight.  

I would surely agree with you analysis.

JustJohn

SAM said:

Thanks for that info JustJohn.  That is the setup that we plan to use.  I thought I may need to add another 50 - 60 watt panel, but your 11 day results are encouraging!  What charge controller are you using?

Sam, I installed a MPPT  type controller sized so I could add another 100w panel if necessary. So far I have not needed the second panel.T@Balong said:

Just John..........which AGM 12v battery did you go with?   And you are saying it fits in the same case as the batteries that normally come with a T@B?

I had to buy a larger battery box ($15.00 at a local auto store) but it fit in the same space as the original battery and I used the same tie down as the original. The battery is a VMax https://www.vmaxtanks.com/XTR12-155-12Volts-155AH-Deep-Cycle-XTREME-AGM-Battery_p_154.html, link may not work but has the info needed to google. 

JustJohn

Sam, The controller is branded as Tracer, but the same controller is sold by Renogy under their name. It is a bit cheaper on Amazon under Tracer brand. I am very pleased with the performance of the controller and it has settings for any type of battery and polarity protection.

irvingj

That's also the same brand of controller that was in our T@B's replacement, a 2015 Roadtrek on a short Sprinter chassis. It seems to work quite well, charging (at least to a degree) even before the sun actually rises. As soon as the sky gets light, it starts showing a "charging" status.

Michigan_Mike

I just installed two 6V Interstate batteries in my aluminum tub on my 2015 T@B and they fit like a glove, no modification needed.  I am charging them with my new 200W Zamp panel and have been boondocking for around 9 days thus far without any issues, running the trailer, my CPAP unit, charging up items, TV/DVD, water pump, LED lights, etc.  Absolutely love this setup and even installed a new Shurflo pump (45 psi/3.5 gpm) which performs much better than the stock unit and has made life much easier.  

gooselady

Stupid question alert:  How does one wire 2 6V batteries together?  Can anyone post a pic?  

gooselady

Also, can anyone post a link or describe the actual type of battery purchased?  I googled Interstate 6V and got a myriad of options.  I don't like options, haha....

Nomad

gooselady - If you search on "6V" or "batteries", there's a bunch of threads with pics.

Sharon_is_SAM

JustJohn, thanks.  We plan to install a Lifeline 150 Ah AGM and since we or the factory could not find a battery box to fit, they are building a box/frame for the battery.  In addition to the 100 watt Renogy suitcase, we went with their 30 amp PWM Wanderer.  I knew if this set up did not work out, I can change to a MPPT.  Glad to hear your success with only 100 watts.  I am anxious to see how the PWM controller compares.

rfuss928

SAM said:

 we went with their 30 amp PWM Wanderer.  I knew if this set up did not work out, I can change to a MPPT. 

MPPT controllers are a Technology that is able to help capture the excess voltage at a panels Maximum Power Point.  This MPP only occurs under near perfect conditions including low temperatures, ideal alignment and crystal clear atmosphere.  Think Denver on a blue winter day at noon.  A condition that rarely exists with our small portable systems.   The technology can not and will not capture any additional energy in less than optimum conditions and is actually less efficient than a standard PWM controller under most conditions.
Spending those funds on additional panel wattage will always produce more energy.

 I just bought a 60w folding panel to supplement the 136w Unisolar panels on my roof for those times when the conditions aren't keeping up with power consumption.   The Unisolars have had me covered in all of our travels for 5 years.  The extra 60w will let me do something to help during those moments when I find myself watching the meters closely as we test our storage capacity.



Have fun!!!

Airliner

rfuss928, Cute camper you have there!

wizard1880

For 6 volt golf cart batteries, many folks go for Trojans.  Personally, I went to batteries plus and got their Duracell branded batteries for about 60% less cost than Trojans, and they're made by East Penn, a close competitor of Trojans.  Under $200 for 230Ah of capacity.