Sorry... another 6 volt battery question

[sgfrye]

Our 2 Wally World 12 volt deep cycle batteries have served us well the past couple years on our TT. Wife and I don't boondock but our fridge is residential and has worked well on 9 to 10 hour trips on the road. Also use fresh water tank and water pump when on the road. Only reason I'm considering switching them out for 2 6 volts is because it's time to replace our pontoon boats deep cycles. I have them powering a trolling motor on the pontoon for fishing and some electronics. They are still in good shape always maintened with charging and fluid checks. My question is what are good mid range priced 6 volts to add to the camper? Not looking for high end or cheap ones. Basically would be powering residential fridge, water pump and one slide to move out and in to access fridge on lunch breaks. Nice to have more battery storage if camp ground power went out for awhile.

[Atlee]

And I've never seen a spate of 6V GC batteries going bad on any RV board I've been on. In fact, I can't remember one person reporting the sudden death of a GC battery. I'm sure folks would have written about it if they had suffered a quick death of one GC battery. I've heard of them slowly going bad after years of use.

All I've ever seen are "what ifs" or theoretical situations being posted about.

4x4van wrote:

Dusty R wrote:
I always looked at it this way. If I was out in the middle of nowhere with 2-6 volt batteries in series, and 1 went bad I would be dead in the water. Where if I had 2-12 volt in parallel and one died I would just unhook it, I would have only half as amp hour, but I would still have some power.

Dusty

Been using 2-6V batteries for about 15 years, and most of my campmates have as well...none of us has ever had a 6v battery just "go bad".

[4x4van]

Dusty R wrote:
I always looked at it this way. If I was out in the middle of nowhere with 2-6 volt batteries in series, and 1 went bad I would be dead in the water. Where if I had 2-12 volt in parallel and one died I would just unhook it, I would have only half as amp hour, but I would still have some power.

Dusty

Been using 2-6V batteries for about 15 years, and most of my campmates have as well...none of us has ever had a 6v battery just "go bad".

[theoldwizard1]

Dusty R wrote:
I always looked at it this way. If I was out in the middle of nowhere with 2-6 volt batteries in series, and 1 went bad I would be dead in the water. Where if I had 2-12 volt in parallel and one died I would just unhook it, I would have only half as amp hour, but I would still have some power.

You probably would not realize that one had died until it had pulled the other one down pretty far, likely below the usable state-of-charge.

[BarneyS]

Please read this if you are quoting someone.

If you feel the need to reply, do it in that thread and not here.
Thank you.
Barney

[Bill_Satellite]

I do happen to have 4 - 8D batteries as my house batteries. 4 more 12V wired as 24V for the engine start and another 12V for the generator.

[ktmrfs]

Bill.Satellite wrote:

So, 1 6V battery rated at 210 would give you 210 ah in 12V when you connect 2. If that's all you need then you are good to go. However, if you had 2 12V batteries that each put out 210ah then you would need 4 6V batteries to provide the same number of AH's.

A 12V 210AH battery is going to be ONE BIG Battery. That's 8D size, the size of TWO 12V end to end. Very Very Very few people run the 8D size 12V. and they are heavy. It's hard to find a 12V battery above 100-120AH.

A typical 8D battery is around 225AH, weighs around 140lbs. Most are made as starting batteries, used in class 8 trucks, big off road equipment. 20"Lx10"wx11"H

They might be used in diesel pusher MH for a starting battery.

[Dakzuki]

Boon Docker wrote:

You should have about the same Amp Hour with a pair of 6 volt as you would with a pair of 12 volt.

A pair of 12V group 24s (What typically comes in a lot of RVs) is about 160 AH. A pair of 6V GC2s which has the same footprint as group 24 but taller is about 220 AH.

[mike-s]

Dusty R wrote:
I always looked at it this way. If I was out in the middle of nowhere with 2-6 volt batteries in series, and 1 went bad I would be dead in the water. Where if I had 2-12 volt in parallel and one died I would just unhook it, I would have only half as amp hour, but I would still have some power.

12 V batteries have twice as many cells, so are also more likely to fail.

When's the last time you had a battery fail suddenly?

[Boon_Docker]

Bill.Satellite wrote:


So, 1 6V battery rated at 210 would give you 210 ah in 12V when you connect 2. If that's all you need then you are good to go. However, if you had 2 12V batteries that each put out 210ah then you would need 4 6V batteries to provide the same number of AH's.

Those would have to be awful big 12 volt batteries at 210ah each. Each one would weigh at least 120 lb.

[Boon_Docker]

Dusty R wrote:
I always looked at it this way. If I was out in the middle of nowhere with 2-6 volt batteries in series, and 1 went bad I would be dead in the water. Where if I had 2-12 volt in parallel and one died I would just unhook it, I would have only half as amp hour, but I would still have some power.

Dusty

Out in nowhere how would you charge up the one good 12 volt that just got discharged by the bad parallel 12 volt?
So unless you had some way if charging the good 12 volt you would still not have power.

[Dusty_R]

I always looked at it this way. If I was out in the middle of nowhere with 2-6 volt batteries in series, and 1 went bad I would be dead in the water. Where if I had 2-12 volt in parallel and one died I would just unhook it, I would have only half as amp hour, but I would still have some power.

Dusty

[Bill_Satellite]

RedRollingRoadblock wrote:

theoldwizard1 wrote:

mike-s wrote:
A GC2 battery is 6V and typically over 200 Ah (the common Trojan T-105s are 225 Ah, but current Interstate/Costco ones are labeled 160, which is the low end).

Where did you pick up that information ? Everything I have read is that the Interstate/Costco GC2 batteries are 225Ah.

I was at Costco today in the metro Portland, OR area. GC2, 210 Ah on the Interstate label, $93 and some change.

So, 1 6V battery rated at 210 would give you 210 ah in 12V when you connect 2. If that's all you need then you are good to go. However, if you had 2 12V batteries that each put out 210ah then you would need 4 6V batteries to provide the same number of AH's.

[RedRollingRoadb]

theoldwizard1 wrote:

mike-s wrote:
A GC2 battery is 6V and typically over 200 Ah (the common Trojan T-105s are 225 Ah, but current Interstate/Costco ones are labeled 160, which is the low end).

Where did you pick up that information ? Everything I have read is that the Interstate/Costco GC2 batteries are 225Ah.

I was at Costco today in the metro Portland, OR area. GC2, 210 Ah on the Interstate label, $93 and some change.

[mike-s]

theoldwizard1 wrote:

mike-s wrote:
A GC2 battery is 6V and typically over 200 Ah (the common Trojan T-105s are 225 Ah, but current Interstate/Costco ones are labeled 160, which is the low end).

Where did you pick up that information ? Everything I have read is that the Interstate/Costco GC2 batteries are 225Ah.

When I went to get GC2s this spring, I swung by the local Costco, expecting to buy a pair. That's what was shown on the shelf tag, I think they wanted $90, too. I suppose it could have been wrong, but that's what it said.

I ended up finding some "black box" Trojans from Magnacharge (they're a Trojan master distributor), rated for 220 Ah, for $100 each. I've seen the Costco ones (in the past) reported to be 208 or 210.

edit: I wish I had taken a picture. The pictures I find on the web show (varies a bit) 107 RC / 210 Ah. But that doesn't make sense - Ah should be less than RC. A Trojan T-105 is 225 Ah, and 447 RC.

edit: OK, stopped by Costco for gas and to check the batteries. They were out of the GC2s, but still had GC8s (8 volt). Those are marked 160 Ah on the battery. Nothing on the shelf tag for either. Maybe they messed up when they had a bunch of GC2s in the spring.