I don't want to start a fight but which battery- 6volt or 12 volt

[kensue49]

I now have a-
3500 watt generator
120 watt solar panel
wind generator for the beach

But I have waited about purchasing batteries for the pup.
I have narrowed it down to-

2 - 125ah 12 volt marine batteries for wally world
or
2 - 225ah 6 volt Golf cart batteries from Interstate battery

I have read some many things and opinions concerning 6 vs 12 volt that I don't know which way to jump.
I only have room for two batteries mounted on the back of the camper"outside".
I have the generator for hot summer time when we are not in a campground.
Weight and price is comparable between these batteries and size is not a factor.
I have changed my lights to LED's.
My fan is a .5 amp computer fan.
My water pump was used last year with one 90 ah battery for 10 days so that isn't a problem.
Which battery??? 

[Alter Ego]

While the Wally world batteries have a higher amp hour rating than the Interstates, I feel the Interstates are a better battery. So, that's what I have. Two U2200s.

[wavery]

It really boils down to personal choice, cost, risk and style of camping.

We chose to go with the Trojan T105s (6-volt golf cart batteries) because of the reputation. Interstate also has a good reputation and is a reasonable choice IMO. I am sooooo done with cheap batteries.

There is a calculated risk using 2, 6V vs 2, 12V. If you get a dead cell in one of the 2, 6V batteries, you can no longer achieve 12V and you have no back-up. You will no longer have use of 12V for the remainder of the camp-out, until you can replace one or (preferably) both batteries. When you choose the 2, 6V batteries you must realise that what you really have is 1, large 12V battery.

If you get a dead cell in one of the 2, 12V, you can unhook the one battery with the dead cell and still maintain 12V (with a diminished total capacity) for the rest of your camp-out. With this option, you really do have 2 batteries.

I am not saying that 2, 12V is the better option. I'm just saying, be aware of the risk involved and figure that into your decision making process.

[Chuck S]

What physical size are the "125 amp hour" marine batteries?  They gotta be Group 27 or 30 and you may have trouble finding a place to put them (and finding boxes).  A pair of these will give you 250 amp hours (sum the amp hours in parallel) compared to the pair of GC2 batteries at 225 amp hours (sum the voltage, not the amp hours in series).

But amp hours are normally highly overstated.  Compare the Reserve Capacity (RC).  More is better here too.  Sum the 12v, but not the 6v. 

Space limitations are a factor.  I have a pair of Trojan T125 GC2 batteries on the tongue.  These have the same footprint as Group 24 (an inch taller) and a pair of these was all that would fit without surgery to the tongue, moving LP tanks, etc.  Rather than a pair of Group 24 I went with GC2.  The T125 and T105 are the same physical size.  The T125 has slightly more capacity.

Battery capacity and weight are directly related.  My pair weighs 132 pounds.

I always buy specialty batteries from specialty battery shops.  Like many others I've killed too many cheap batteries.  I had to order the T125s with the terminals I wanted.



-- Chuck

[ngatel]

Originally I bought into the two 12 volt batteries provide a "backup" plan theory. But it did not provide the nearly the amp hour capacity of a two 6 volt set up. Also most 12 volt batteries are not true deep cycle. Pretty unlikely you will suddenly "lose" a cell in your battery bank. If you leave home with a fully charged bank, very unlikely you will suddenly drop a cell. Since we have solar, the panels keep the bank charged and also equalize the bank when needed. We occasionally put the trailer in our garage, but since we camp so often it is mostly in the driveway between trips.

Next dilemma was mounting. Much easier to find a suitable mounting system for a pair of 12 volts, than 6 volts that fit my needs.

Here is a link to the 12 volts used on my Starcraft. I moved it to the Niagara when we purchased it. The only mod on the Niagara was to move one of the bottom brackets, which meant drilling out a couple of rivets, drilling a couple new holes in the frame, and securing with new rivets. Dual 12 volt

Your mileage may vary.



When I found this box designed specifically for two Trojan T series batteries, I bought it and two T-125s. I was not having any problems with the 12 volts, it was a definite upgrade. Found the box at Las Vegas Trailer Supply, while on a trip to Lake Mead. At the time, we had just added a 130 watt panel to our our existing 120 watt panel, and now we have the ultimate system. No generator needed in any weather or length of stay. I wish I had bought these in the beginning. We do not need A/C. Dual 6 volt

[parrothead]

I'm working on making the same decision myself.  My cheap 12V Group 24 Costco batteries just died after 7 1/2 years of service (actually, 1 dead cell in one of the batteries and 1 weak cell in the other).

I had been thinking that I'd go with a pair of 6V batteries when my current ones died but now I'm not as sure. 

Before our last trip a couple of weeks ago, I charged the batteries.  The first one charged fine (although I took a hydrometer to it later and one cell was just slightly weak).

I hooked the other one up to the charger the day before we left.  When I went out the next day to move the batteries to the tongue, it hadn't charged.  I took the hydrometer to it and one cell was flat dead.

As this was only a 4 day trip, I knew one battery would do it so I put it on the tongue and off we went.  Had these been 6V, I'd have been out buying batteries that morning.

I kow the odds of this happening again any time soon is small but it got me thinking that two 12V might be a better choice.  Never had issues with needing more than what 2 Group 24s can provide so I don't see the advantage for us but I now see the possible down side.

We don't have a long trip planned till late June so I've got a while before I need to buy anything.  Guess I'll do some shopping and see what the cost differences are and factor that in as well.

[kensue49]

The 125 amp hour 12 volt batteries are group 29.
I check on the Interstate battery U2200 last year.
I need to check on their price now.

[wavery]

We don't have a long trip planned till late June so I've got a while before I need to buy anything.  Guess I'll do some shopping and see what the cost differences are and factor that in as well.

Here is a tip......if you shop by price, you will probably want to go with 2, 12V for a couple of reasons. Less expensive batteries tend to fail sooner (sometimes in a few months). That's when a "Back-up battery becomes important. Also, cheaper 6V batteries are more prone to failure than cheaper 12V.

If you research the quality brands of batteries, then shop places to buy the best choice in your budget, 6V may be the way to go as good quality 6Vs usually last about 5 years without issues.

Having said that, batteries are a dirty business. You are dealing with mixture of self-eroding metals and acid. The best quality batteries sometimes fail. It's just a fact of life.

[parrothead]

Here is a tip......if you shop by price, you will probably want to go with 2, 12V for a couple of reasons. Less expensive batteries tend to fail sooner (sometimes in a few months). That's when a "Back-up battery becomes important. Also, cheaper 6V batteries are more prone to failure than cheaper 12V.

Shopping by price doesn't mean buying the cheapest thing I can find, it means looking at the options and factoring cost into the mix.  My last battereis were Kirkland brand from Costco and survived 7 1/2 years of regular use.  They weren't the cheapest batteries I found at the time but they were reasonably priced and had a good guarantee.  Plus I'd used their batteries in my cars and they had provided good service.

I'm not sure I can justify the additional expense of 6V vs. 12V in the same quality level as I don't need the extra capacity and, after my recent experience, like the idea of the batteries functioning independently.

[kfriceman]

Here is a tip......if you shop by price, you will probably want to go with 2, 12V for a couple of reasons. Less expensive batteries tend to fail sooner (sometimes in a few months). That's when a "Back-up battery becomes important. Also, cheaper 6V batteries are more prone to failure than cheaper 12V.

Shopping by price doesn't mean buying the cheapest thing I can find, it means looking at the options and factoring cost into the mix.  My last battereis were Kirkland brand from Costco and survived 7 1/2 years of regular use.  They weren't the cheapest batteries I found at the time but they were reasonably priced and had a good guarantee.  Plus I'd used their batteries in my cars and they had provided good service.

I'm not sure I can justify the additional expense of 6V vs. 12V in the same quality level as I don't need the extra capacity and, after my recent experience, like the idea of the batteries functioning independently.

Those Kirkland batteries are manuafactured by Johnson Controls which is the same company that brings the Sears Diehard to market; definetely no slouch in the battery building business.

-Kevin

[parrothead]

Those Kirkland batteries are manuafactured by Johnson Controls which is the same company that brings the Sears Diehard to market; definetely no slouch in the battery building business.

-Kevin

Wasn't aware of that, thanks for the info.

[wavery]

Shopping by price doesn't mean buying the cheapest thing I can find, it means looking at the options and factoring cost into the mix. 

That was my point exactly.........

[chipperone1]

   12 volt.

   I am going with two Interstate sealed lead acid, absorbed glass mat, deep cycle 100Ah batteries

[wavery]

   12 volt.

   I am going with two Interstate sealed lead acid, absorbed glass mat, deep cycle 100Ah batteries

I've heard good things about those. They're light weight, compact, zero maintenance and you can put them anywhere, even upside down, if you want.

[parrothead]

Just swung by Costco and they still have the Kirkland batteries like my old ones and they are $62 each.  If I can get anywhere close to the 7 1/2 years I got out of the last set, I'll be quite satisfied.