The 17' car hauler that I recently bought has a receiver welded on and braced very nicely for a removable winch along with a battery tray. I am buying a mount for the Warn that I pulled off of my old Jeep but it won't only get used on the trailer. Here is my thought, run cables to a quick disconnect on the truck hitch for use only on the truck, make a cable that is configured so that it can connect the truck either directly to the winch or to the battery to charge while driving, then mount a battery on the trailer with 2 sets of cables (1 to power the winch on its own and the second to connect to the truck for charging). The connectors will be configured so that it is impossible to mistakenly reverse the polarity I don't want to rely solely on the battery mounted on the trailer because I know I will forget to plug it in to the tender and it won't be any good when I need it. Has anyone wired up in this manner? Are there any reasons to absolutely not do it this way? I have attached a basic diagram of the plan I am thinking.

Note: The positive lead coming from the truck will have a solenoid wired into it with a switch in the cab to energize it so that the battery or winch (whichever is plugged in) will not run the truck battery dead.