Help me idiot proof my battery box size

[ripperj]

I am rebuilding the interior of my alaskan from scratch, and have room to build a decent sized battery enclosure. I am very familar with commercial DC systems and charge /venting concerns, maintenance ect. I am not really up on auto/expo batteries, seems like many use group 31. I basically want to build an enclosure big enuff for two batteries laid end to end the long way. I dont want to build around the group 31, and regret it later if I want to go to a differnt battery.
Without wasting any more space than needed, what would you build for interior height and depth (front to back) (length is no issue less than 45") to be flexible with what batteries go inside?
The batteries will go under a removable step, in front of my water tank(also under a removavble step, but higher than the batteries.
i have a pic that I can upload here shortly that will make more sense.
Thanks a bunch

 

[java]

If you have enough room, two 6V golf cart batteries will get you a lot further than a couple for G31's AH wise.

 

[ripperj]

Is there a standard size for golf cart batteries? I did a ton of research, on most all aspects of my build , but fizzled out on the electrical.I need to get rocking and rolling on the interior build, and the battery box is a big chunck of the structure.
The golf cart batteries I looked at are GC2. 7.19 deep x10.68 H, but they are normal looking lead acid types,
The Interstate battery truck comes to my local auto parts place often, any reason not to use them?

Seems like 8.5 deep by 11 high would be a safe bet for the battery box interior( I will have to ensure that includes the posts.)

 

[ripperj]

Here is a nice battery size chart
http://www.rtpnet.org/teaa/bcigroup.html

 

[wrcsixeight]

+1 on the 6v GC batteries. I have a group 31 from US battery and it is new, and a POS. Apparently group 31's do not have good electrolyte to plate surface ratios. Mine requires ridiculous voltages and durations to get specific gravity up where it should be. Then the next discharge recharge cycle the readings will be back down in the red, despite the battery not being able to accept any more current at 14.5v. I regret this group31 purchase to an incredible degree, and USbattery is supposed to be among the top dog battery makers, and they cannot get this size format right. Avoid

The group 31 size was originally designed to accommodate 1000CCA+ starting batteries and do not translate well in a deep cycle format

 

[ripperj]

thx for the help, I am going to see if I can find a maintenance free,sealed GC2