Do I need a battery box??

On our previous 5er I had two 6v in the front storage w/o a box for 8 years. There were no leaks to the living area and the vent hole up high was still open. The floor of that area was steel and it had lots of gaps for circulation. I strapped them down with heavy nylon belts. I NEVER saw a speck of corrosion on anything in the compartment. Even when the batteries got old and wouldn't hold enough charge to be useful and they started corroding the posts, the rest of the compartment and stored items were unaffected. Our current 5er has the batteries in a small wooden compartment with a louvered door and no special battery box. There is no room to use anything to secure them, so I cut styro blocks to fill the gaps so they can't move much. Again, no problems or corrosion on anything. Just like auto batteries, corrosion and gassing isn't a problem when they are in good shape and charging properly. I would try it w/o a box and keep an eye on things. Make sure there is high and low vent paths. Craig