Replacing 12v batteries with 6 volt

[Conestoga]

It is time to start thinking about replacing our Hawk camper batteries. Has anyone replaced their dual 12v batteries with dual 6 volt batteries? I believe the FWC factory rig is using this setup. As storage space is limited would hate to lose the space between the top of the battery compartment & hinged lid. My understanding is that the 6 volt batteries in series offer more A/H storage capacity.

 

[Bad Habit]

Yes and no. Depends on what batteries. 2 x 220ah 6V will give you 220ah at 12v. 2 x 150ah 12v will give you 300ah
6v "Golf cart" batteries are typically true deep cycle and are designed for deeper and/or more discharges. Because you need both for 12v however, if one does fail, you have no system.

 

[Trailbob]

I converted our travel trailer to (2) 6V Lifeline batteries (220ah). They are expensive, but excellent quality. I'm happy with the change and added capacity. I considered doing this when I needed new batteries for our Hawk in 2015. I originally had one group 24 agm battery with around 80 ah but ended up replacing it with two group 24s, for about 160 ah capacity. Cost was one factor, as was weight (my old back putting them in the camper). But the main reason was that two group 24's was more than adequate for our needs.

When I was researching batteries, I read that (quality) 6v batteries are true deep cycle batteries, and are better constructed with thicker plates than most deep cycle/starting 12v batteries. If I had higher power needs (like a 12v fridge), I likely would have put 6v agms in our Hawk also.

 

[Jack]

If you have space for two 6V agm batteries, that is definitely the way to go. Trojan and Full River make excellent high quality golf cart batteries. Because of the volume, golf cart batteries are lower cost than other form factors, so as long as you have room - our Fleet front dinette required a small modification to the battery compartment (1/2 hour of work).

When you connect two 12V batteries in parallel, there will be a small current flow between the batteries until the batteries reach an equilibrium. Over time, as one battery ages faster than the other, the other battery will catch "down" to the level of the faster aging battery. Two 6V batteries in series do not have this problem - you get the max age out of each battery.

If you do connect two 12V batteries together, jumper the two positive terminal together and the two negative together (quite exciting the other way). What's important is that you then connect the batteries into the camper from the terminal of one battery and one terminal of the other battery.

FWC supplies Exide (?) marine batteries because they have a two year end-user warranty. Marine type agm batteries have a shorter life than true deep cycle batteries. $ for $, deep cycle are a better value.

Whatever your setup, depth of discharge determines your battery life. Frequently discharging below 70% can take months to years off the life Complete discharge can kill a battery. Want to find out? Leave your 3-way fridge on overnight without the engine running.If you keep the discharge to 30% or less, you will get moths to years more life.

Two 12V batteries in parallel won't help much if one battery fails - the other battery will quickly discharge into the failed battery. These batteries almost never fail as an open circuit.

 

[SCUD]

+1 on two 6-volts. We've used them since 1992 in our motorhomes, and replaced the single 12-volt Exide in our 2016 Fleet with two Full River 6-volts.

 

[JaSAn]

. . . 6-volts are big and heavy, and were more expensive. They take up considerably more room. They aren't as available, so if you have an issue, you have more problems finding replacements. Also, they may or may not be constructed as well, meaning depending on how you use your rig, they may be more fragile.

Golf cart batteries are heavy because they have more lead = deep cycle. Mine are smaller than two 12V batteries. No true deep cycle battery is going to be light.

I got my GC2s at Sam's Club. Cosco carries them. Some Walmarts carry them (can have them delivered to any Walmart). BatteriesPlus carries them. Any town that has a golf course will have at least one store that carries golf cart batteries.

Golf cart batteries are built to take the abuse of kids joy riding in a golf cart. GC2s are actually built stronger (to support the added weight of the lead).

A good discussion on the differences between marine and deep cycle batteries:
http://www.pbase.com/mainecruising/deep_cycle_battery

jim