Its not quite an artists concept, but I think it does an ok job of illustrating the point. Here is a photo of the actual case that I have, and have been using with a 150WHr battery, albeit with a charge controller that I purchased. You can see the waterproof circular connectors on the case and wiring, load relay, and in-line fuses in this photo. I plan on changing the connectors out with Souriau UTS connectors - I don't really care for how the current Bulgin 6000 ones mate. My new PCB will eventually be assembled and eventual put into this case as a test platform.