switching to two 6 volt batteries?

[gitpicker2009]

I'm about to replace my two AF1150 batteries. They're currently Interstate Deep Cycle 12 volts wired in parallel.
I'm thinking of going with two 6Volt golf cart batteries. Sam's sells the Duracell EGC2 for 150 bucks. Specs:
20 amp hour rate: 230
5 amp hour rate:174
Battery electrolyte composition: acid
Battery end type: top post
Battery purpose: deep cycle
BCI group size: GC2
Freight class: 65
Minutes at 25 amps: 448
Minutes at 75 amps: 120
Terminal type: DIN
Volts: six

I was thinking that with the 2 two wired in series, I'd be better off on the Amp Hour rating. Any opinions?

Thanks as always

[deltabravo]

Grit dog wrote:
Wow that’s a pretty matter of fact recommendation for a very mid grade solution.

This wasn't a "mid grade" solution in 2015 when I did that upgrade.
That upgrade was long before Lithium batteries became commonplace for RV systems.
At the time I installed the AGMs, no one have ever mentioned Lithium batteries.

My current AF camper (a 992) uses a pair of Battleborns that I took out of a Nash 17K I installed them in a year earlier, when I still had the 811.

Battleborn batteries in my AF 992

Grit dog wrote:
There’s no problem getting a couple 200ah SLA 6v batteries in that tray or a 200ah 12v AGM.

Two group 31 AGMs were the easiest to install when I did the upgrade in my 811. Two smaller batteries are a lot easier to lift into the compartment that's at eye level than one large 200ah battery (which I never found when I was searching for battery upgrades 8 years ago)

Grit dog wrote:
...and actually fit with not modifications.

No mods were necessary to fit the group 31 AGMs.
I jettisoned the useless, "weight adding" tray which serves no practical purpose other than adding weight and taking up footprint space that prevents larger batteries from being used, and reduces vertical height making it more difficult to make my battery connections.

[deltabravo]

valhalla360 wrote:
If your charger is causing large amounts of gassing, fix/replace the charger.

High quality chargers (3 stage units) that I use do cause some gassing of flooded wet call batteries.
Every RV I've owned, I disable the stock converter and use an inverter/charger for my charging needs.

With the minimal space in an AF truck camper battery compartment above the batteries, a "filling system" isn't going to solve the issue of not being able to check/fill the batteries.

[Grit_dog]

deltabravo wrote:
The problem with 6v lead acid wet cell batteries in an AF camper is the height of them, and the pointless battery slideout tray, and the inaccessibility of checking the fluid levels due to the height. That tray doesn't allow access to the inner battery either.

Your best bet is to ditch the tray and go with two group 031 AGM batteries, so you never have to check fluid levels or deal with acide puking wet cells ever again.

A lot of AF owners in the FB group have done the switch to AGM.



Here's how I did it on my AF 811

Wow that’s a pretty matter of fact recommendation for a very mid grade solution.
There’s no problem getting a couple 200ah SLA 6v batteries in that tray or a 200ah 12v AGM.
Both of which provide the same power for less $ and actually fit with not modifications.

[3_tons]

deltabravo wrote:

valhalla360 wrote:
10min to add water a couple times per year...ehhh. Should be checking on connections etc anyway.
Never spilled acid or had fumes do any damage, so...ehhh.

Fumes will corrode things when the batteries gas when charging.

It's more like 30+ minutes to check batter fluid level in an AF camper.
You can't get access to the inner battery, even though they are on a useless sliding tray that most AF owners despise.
The tray only slides half way out.

The only time I was able to check the water was when I took the camper off the truck for the winter and was able to disconnect the batteries and removed them to check fluid.

Checking water when the camper was on the truck was an impossible feat because getting them out required the use of a ladder. Carrying them down a ladder isn't fun (or safe)

I had the same tight battery box… My solution for watering the two GC’s was to remove the tray and add an automatic watering system - worked perfectly for 15 years 🙂

https://www.amazon.com/Flow-Rite-RV2000-Pro-Fill-Battery-Kit/dp/B001FCAXT0/ref=sr_1_9?crid=377F0J7WNJ1XS&keywords=flo+rite+battery+watering+system&qid=1689773861&sprefix=Flo+rite+%2Caps%2C159&sr=8-9

Also, for the sake of testing for corrosive off gassing, I’m not saying they don’t off-gas, but for ad hoc testing purposes I’d flattened out and taped a strip of silver solder inside the roof of the vented battery box as a improvised sorta coal miner’s canary idea, but over the years I never saw any signs of silver discoloration whatsoever, or on the terminals! - this may be due to the compartment door’s venting…

At least that was my own experience, however I’ve since switched to LiFePo4 lithium and have been extremely pleased…

3 tons

[valhalla360]

deltabravo wrote:

valhalla360 wrote:
10min to add water a couple times per year...ehhh. Should be checking on connections etc anyway.
Never spilled acid or had fumes do any damage, so...ehhh.

Fumes will corrode things when the batteries gas when charging.

It's more like 30+ minutes to check batter fluid level in an AF camper.
You can't get access to the inner battery, even though they are on a useless sliding tray that most AF owners despise.
The tray only slides half way out.

The only time I was able to check the water was when I took the camper off the truck for the winter and was able to disconnect the batteries and removed them to check fluid.

Checking water when the camper was on the truck was an impossible feat because getting them out required the use of a ladder. Carrying them down a ladder isn't fun (or safe)

They make battery filling systems to address access problems. They are pretty simple and not expensive.

If your charger is causing large amounts of gassing, fix/replace the charger.

[JimK-NY]

I have Lifeline AGM batteries. I go years without even opening the batter compartment to check on them. In order to use the largest possible batteries I removed the slideout tray. It would be a major issue if I had regular batteries that needed to have water added.

The lack of maintenance needs makes the extra cost of AGM batteries worth it for me.

[deltabravo]

valhalla360 wrote:
10min to add water a couple times per year...ehhh. Should be checking on connections etc anyway.
Never spilled acid or had fumes do any damage, so...ehhh.

Fumes will corrode things when the batteries gas when charging.

It's more like 30+ minutes to check batter fluid level in an AF camper.
You can't get access to the inner battery, even though they are on a useless sliding tray that most AF owners despise.
The tray only slides half way out.

The only time I was able to check the water was when I took the camper off the truck for the winter and was able to disconnect the batteries and removed them to check fluid.

Checking water when the camper was on the truck was an impossible feat because getting them out required the use of a ladder. Carrying them down a ladder isn't fun (or safe)

[deltabravo]

The problem with 6v lead acid wet cell batteries in an AF camper is the height of them, and the pointless battery slideout tray, and the inaccessibility of checking the fluid levels due to the height. That tray doesn't allow access to the inner battery either.

Your best bet is to ditch the tray and go with two group 031 AGM batteries, so you never have to check fluid levels or deal with acide puking wet cells ever again.

A lot of AF owners in the FB group have done the switch to AGM.



Here's how I did it on my AF 811

[LamboDesigns]

When my original equipment batteries were gone I went with the two 6v GC batteries. They did better than the original ones but after running the furnace all night there were mornings where they were pretty much shot if it was very cold. I would need to run the generator to make the morning coffee.

After 6 years it wasn't getting any better so I took a deep breath and went lithium. The price has come down enough that they make sense for the long term investment. They also come in a much smaller form factor now for the 100ah batteries with ones even smaller than I bought. I went with 3 Redodo 100ah "smart" batteries for the following reasons. 1) They were small enough to fit 3 and I wanted a 3000 watt inverter so I never have to worry about what the wife turns on. 2) Decent price and they are even cheaper ($350) now than when I bought them. 3) With a single button on each battery I can turn them off so they are not charging/discharging when not in use. Single push turns them back on. Great feature. 4) They have low temp charging protection. 5) They are a LOT lighter than the GC batteries making installation/removal much easier.

There are a few companies that look like they sell the same battery.... just a different name. I went with Redodo because they were the cheapest at the time. I had an issue when I first hooked them up, that was mainly a misunderstanding on my part on how the sleep mode works, and their customer service was outstanding. Emails were promptly answered and they were very professional and knowledgeable. Batteries are working great and I added a Renogy shunt to monitor them. When I fire up the furnace it shows it will run for 22 hours and I can run the microwave and make coffee at the same time. My goal was to never worry about running out of battery and with this setup I've achieved it.

[valhalla360]

HMS Beagle wrote:
I would never go back to flooded lead acid batteries, just due to the inevitable corrosion. However AGM batteries do have to be correctly charged, or their life will be short. That means correct voltages, and for sufficient time, somewhat frequently.

There is an argument for two 12V vs two 6V: if you run an inverter with high current draw, the two 12V batteries will have lower internal resistance than two 6V, and so lower voltage drop while running the inverter.

Technically true but with only a couple batteries, you probably shouldn't be pulling 2-3,000w anyway with an inverter. If you are trying to pull that kind of wattage, you should really have more than 2 batteries (6v or 12v).

500-1000w for a cofee maker or microwave shouldn't be a problem with a pair of 6v wired for 12v, so long as you keep it down to a few minutes use.

[HMS_Beagle]

I would never go back to flooded lead acid batteries, just due to the inevitable corrosion. However AGM batteries do have to be correctly charged, or their life will be short. That means correct voltages, and for sufficient time, somewhat frequently.

There is an argument for two 12V vs two 6V: if you run an inverter with high current draw, the two 12V batteries will have lower internal resistance than two 6V, and so lower voltage drop while running the inverter.

[Latner]

Grit dog wrote:

Latner wrote:

gitpicker2009 wrote:
I'm about to replace my two AF1150 batteries. They're currently Interstate Deep Cycle 12 volts wired in parallel.
I'm thinking of going with two 6Volt golf cart batteries. Sam's sells the Duracell EGC2 for 150 bucks. Specs:
20 amp hour rate: 230
5 amp hour rate:174
Battery electrolyte composition: acid
Battery end type: top post
Battery purpose: deep cycle
BCI group size: GC2
Freight class: 65
Minutes at 25 amps: 448
Minutes at 75 amps: 120
Terminal type: DIN
Volts: six

I was thinking that with the 2 two wired in series, I'd be better off on the Amp Hour rating. Any opinions?

Thanks as always

Good choice. Mine are going on 7 years now and seem to be as good as when I bought them.

It’s not a good choice because they won’t fit in his camper….doesn’t matter if they last 20 years….if they’re sitting at home.

Never said they would fit, only that they are good batteries. I assume he knows how to read dimensions and use a tape measure. :R

[StirCrazy]

gitpicker2009 wrote:
I'm about to replace my two AF1150 batteries. They're currently Interstate Deep Cycle 12 volts wired in parallel.
I'm thinking of going with two 6Volt golf cart batteries. Sam's sells the Duracell EGC2 for 150 bucks. Specs:
20 amp hour rate: 230
5 amp hour rate:174
Battery electrolyte composition: acid
Battery end type: top post
Battery purpose: deep cycle
BCI group size: GC2
Freight class: 65
Minutes at 25 amps: 448
Minutes at 75 amps: 120
Terminal type: DIN
Volts: six

I was thinking that with the 2 two wired in series, I'd be better off on the Amp Hour rating. Any opinions?

Thanks as always

I originally went with two GC2 batteries. measure your opening for your battery compartment twice, then measure the height of the batteries. The largest I could fit in mine was 210AH as the 220AH were 1/4" too tall to get in the space. they seam to get taller as the capacity goes up. As it is, I had to a buy an auto watering set up so I could add water to them when they needed it, but I would recommend that for any setup now as it made topping off water so fast and easy.

I have since gone to LFP to save space and weight, but the 6V batteries worked good with my solar when I had them

[StirCrazy]

pianotuna wrote:
Consider recondtioned telecom batteries. Mine are 139 amp-hours each @ 12 volts. Measure to make sure they would fit.

The problem with going that way Don is that with our truck campers most of us are already flirting with the weight limit or have already gone over. Anything we can do to save weight is better in the long run. at 100lbs per 140AH Telecome battery that would take away 200lbs of my capacity where I could just do 2 100AH LFP for a total of 88 lbs and have more usable capacity and use that extra 120lbs of capacity for something else.