Off grid power box

Im trying to come up with ideas. I want an off gride power box that will sit in the back of the truck, and secured do the batteries dont slide around. I want it to be removable if needed. And i dont want it taking up much room.




I have a bed rack on order so cant go with a storage box. Goose Gear makes a base system that sits in the bed, but its $700.

Was just curious if anyone on here had any imput. Thanks in advance

 

I would probably build a wooden box so the terminals are protected then add some eye bolts to the bed where I want them held and ratchet strap them in. You can also get a battery box for an RV, they are likely cheap.

 

I could also fab up a box on the wheel wells...