12v AGM or golf cart

[sailski]

Trying to determine which way to go when my 2 12V group batteries die. I do a lot of camping at public campgrounds. National and state parks, national forest, Army Corps of Engineer and BLM. Although my batteries are OK now they only have 75 - 100 Amps of capacity and I think I need more like 125. I have 300 watts of solar for charging and a generatod that should replenish the battery bank. Unfortunately the Sprinter chassis is limited on how much weight it can carry and I am at the limit right now.

[SidecarFlip]

I'd get a pair of Trojan 104's and cable them is series for 12 volts. They are fantastic 6 volt batteries.

[ScottBrownstein]

x2 on the Trojans

[325BH]

I have two Trojan T105 batteries and have been very satisfied. Would certainly recommend them, however I will admit to knowing nothing about AGM batteries.

[SidecarFlip]

Originally Posted by ScottBrownstein

x2 on the Trojans

Like any wet cell battery, you do have to maintain the water level. They arent forget about batteries.

My next set will be Li-Iron. Have to save my pennies though. One 100 AH one is around 800 bucks today but I'm sure the price will drop.

[Rich.M]

I went sealed AGM after having to clean ,sand, prime and repaint the inside of my battery box when one of the OEM wet cell batteries leaked. I'm sure the Trojans give great performance but with the solar I just don't reach discharge levels lower than 30 to 40% on my Sprinter set up before the next solar day starts. Lowest morning voltage has been 12.29 before sun up and I don't pay much attention to usage. The AGM performance is satisfactory for these units without the maintenance chores or leak risk.
The AGM do charge faster than my last wet cells and can take all 24 amps peak solar output right up to full charge often by 11-12 o'clock

[RudysWorld]

Forest River Reps discourage the use of 6v batteries. Can cause issues with the converter. Good Luck!

[13larry]

12v dc is the same with 2 6v or 2 12v so why would the inverter care?

[JLeising]

On our MBS Solera "S", I believe the battery area under the step is too short for the height of 6 volt Golf Cart batteries. A forum member has reported he successfully modified his MBS to use GC batteries by adding spacers under the step. A different forum member tried the same, but had seal problems with his spacers, resulting in LP detector alarms from battery charging gases. I believe he ended up going back to two 12 volt batteries. Suspect you can find these forum entries with a search.

[RudysWorld]

Originally Posted by 13larry

12v dc is the same with 2 6v or 2 12v so why would the inverter care?

I am sure there is someone on here that can describe better than I. 12v battery is not always at 12 volts and 6v battery is not always 6 volts. When you combine the 6v batteries in series it can exceed the voltage range of the converter. I don't have an inverter so I will not speak to that.

[Sandy B]

Can you folks tell me what I have here? I can find no identification on these things, don't know type, voltage, manufacturer etc.As far as I know these are the original batteries for my 2014 Georgetown 270 motorhome. From the cell covers I assumed "no service necessary" and have not touched them. As they are now 3 years old I feel I am facing replacement and like the OP am trying to figure out which way to go. This is not an easy area to work in so I would like a service free system if possible. Is AGM the only type that does not need water added? Is that what these are? Am I looking at 2 12 volters?
Georgetown Batteries.jpg

[garbonz]

Originally Posted by RudysWorld

Forest River Reps discourage the use of 6v batteries. Can cause issues with the converter. Good Luck!

Need a reference for this contention, as it seems to be a new recommendation. I have never heard of it before, has anyone else?

[garbonz]

Originally Posted by RudysWorld

I am sure there is someone on here that can describe better than I. 12v battery is not always at 12 volts and 6v battery is not always 6 volts. When you combine the 6v batteries in series it can exceed the voltage range of the converter. I don't have an inverter so I will not speak to that.

Both have 6 cells, identical chemistry, NO voltage difference

[garbonz]

Originally Posted by Sandy B

Can you folks tell me what I have here? I can find no identification on these things, don't know type, voltage, manufacturer etc.As far as I know these are the original batteries for my 2014 Georgetown 270 motorhome. From the cell covers I assumed "no service necessary" and have not touched them. As they are now 3 years old I feel I am facing replacement and like the OP am trying to figure out which way to go. This is not an easy area to work in so I would like a service free system if possible. Is AGM the only type that does not need water added? Is that what these are? Am I looking at 2 12 volters?
Georgetown Batteries.jpg

SAndy, those are conventional 12 volt wet cells and need to be checked for water periodicallly. If you don't want to do that then get AGM's of a similar size (measure them). If you haven't check them I wouldn't be suprized if they were pretty. Dry.

[AquaMan]

If your converter is a WFCO it may be hard on it charging a couple of 6 volts, but the voltage has nothing to do with it, it's the charging amp draw. A good converter with a multi stage charger should have no problem. My Georgetown came with 4 6v batteries from the factory, but it has a PDI converter that handles it fine.

[smfranks]

Originally Posted by sailski

Trying to determine which way to go when my 2 12V group batteries die. I do a lot of camping at public campgrounds. National and state parks, national forest, Army Corps of Engineer and BLM. Although my batteries are OK now they only have 75 - 100 Amps of capacity and I think I need more like 125. I have 300 watts of solar for charging and a generatod that should replenish the battery bank. Unfortunately the Sprinter chassis is limited on how much weight it can carry and I am at the limit right now.

Well, I am going to say none of the above. I run 12V LiFePO4 batteries. Yes, the original cost is high, but cost per amp/hour over the life of the batteries is lower, weight is much less, no maintenance, faster charging, no worry about drawing them to low, last a LOT longer. Charge them before you store in the winter, and they are still at 90% in the spring. Check out https://battlebornbatteries.com/ I do not work for them but have loved the levels of service, advice, and product.

[amblt]

Originally Posted by 325BH

I have two Trojan T105 batteries and have been very satisfied. Would certainly recommend them, however I will admit to knowing nothing about AGM batteries.

I know the only thing that's important to me about AGM vs Flooded- They don't gass off when correctly charged, so I can charge them safely in my apartment if it's necessary. (winter in the snow belt, for instance, when my deck is unuseable).

Cheers

[camaraderie]

Sandy...you have a pair of WET CELL 12V dual purpose batteries...that DO need to be watered and at this point you may have little left and bad plate exposure...Each plastic cover covers 3 of the 6 cells. Use only distilled water to refill. Profill makes a set of hoses and caps to make watering this two battery setup as easy as squeezing a bulb.
They look like Group 27's to me which would mean you have roughly 180-200 amp hours of capacity. Measurement should be 12.10x6.80x8.90 ...
if smaller (10.5")you have group 24's which will give you roughly 150 amp hours.

As to the original post...in a two battery configuration, I continue to prefer 12V since even in failure you have one good battery...unless you don't recognize the failure in time...i.e. you didn't get a true battery monitor...which SHOULD be a must for boondockers.
Trojan does not presently make a 6V AGM ...so regardless of your mounting space...12V is the option in a Trojan AGM.
They have a new line called RELIANT which WILL offer a 6V AGM at a list of around $250 each but that is not due out until mid year.
Most of the AGM "deep cycles" on the market are dual purpose...which is fine for the non-boondocker who wants the low maintenance, and other benefits of AGMs.
If you want a true deep cycle AGM for boondocking ...Trojan or Lifeline would be my choice unless you wanna get hi tech with a Firefly or LiFePO4 spendy set up.

[Tom48]

Originally Posted by garbonz

Both have 6 cells, identical chemistry, NO voltage difference

May that storey creating vudoo about 6v X 2 in series being different from a pair of 12 v batteries in parrellel was a commercial on President Trump's nemesis The FAKE NEWS.

[Tom48]

Originally Posted by garbonz

Need a reference for this contention, as it seems to be a new recommendation. I have never heard of it before, has anyone else?

No never. Nor has the service manager from by dealer or the retired 45 yr experienced rv svc mgr I camp with. First thing most all recommend, IF YOU HAVE THE HEAD ROOM FOR THE TALLER GC-2 batteries is TWO 6s in the same foot print as a pair of Group 24s is 50% more available amperage.